X-ray spectropolarimeter
E. O. Baronova, M. M. Stepanenko, and A. M. Stepanenko
We have constructed a novel single-crystal x-ray spectropolarimeter that separates spatially the two perpendicularly polarized components of an x-ray beam. We have tested this device by using an x-ray tube, and confirmed its performance to be satisfactory as expected from its design. ... [Rev. Sci. Instrum. 79, 083105 (2008)] published Thu Aug 7, 2008.
Photoinduced microchannels inside silicon by femtosecond pulses
Tao Chen, Jinhai Si, Xun Hou, Shingo Kanehira, Kiyotaka Miura et al.
We reported on the fabrication of microchannels in the interior of silicon wafers using a femtosecond laser of 800 nm wavelength, which was in the absorption region of silicon. The scanning electron micrographs showed that microchannels were induced inside the silicon wafer when the femtosecond las ... [Appl. Phys. Lett. 93, 051112 (2008)] published Thu Aug 7, 2008.
Resolution of photon-recoil structure of the 6573-[A-ring] calcium line in an atomic beam with optical Ramsey fringes
R. L. Barger, J. C. Bergquist, T. C. English, and D. J. Glaze
The photon-recoil components of the Ca 6573-A line have been resolved using the three-zone optical Ramsey interference technique with an atomic beam. Linewidths as narrow as 3 kHz HWHM (line Q of 8 x 10) are reported for zone separations up to 7 cm. An indication of the light-shift-induced contracti ... [Appl. Phys. Lett. 34, 850 (2008)] published Thu Aug 7, 2008.
Microbolometers for infrared detection
Tien-Lai Hwang, S. E. Schwarz, and D. B. Rutledge
We describe a novel room-temperature detector for the wavelength range 101000 [mu]m. This detector consists of a thin bismuth bolometer film with dimensions much smaller than a wavelength. The small size of the detector results in reduced NEP and faster response. A video NEP of 1.6 x 10 W/Hz is obta ... [Appl. Phys. Lett. 34, 773 (2008)] published Thu Aug 7, 2008.
Dual-wavelength demultiplexing InGaAsP photodiode
J. C. Campbell, T. P. Lee, A. G. Dentai, and C. A. Burrus
We report the successful operation of a new photodiode structure capable of detecting and demultiplexing two wavelength bands simultaneously. Wavelength discrimination is achieved with a multilayer structure that incorporates p-n junctions in two InGaAsP layers having different band gaps. In initial ... [Appl. Phys. Lett. 34, 401 (2008)] published Thu Aug 7, 2008.
The detection of 300 [degree]K blackbody radiation with Rydberg atoms
T. F. Gallagher and W. E. Cooke
Using selective field ionization (SFI) of Na Rydberg atoms we have detected the 300 degrees K blackbody radiation which induces the Na transitions 17s-->17p, 18s-->18p, 17d-->18p, and 17d-->18f frequencies of 27.3, 22.8, 7.4, and 41.6 cm, respectively. Investigation of the probable collisional effe ... [Appl. Phys. Lett. 34, 369 (2008)] published Thu Aug 7, 2008.
Quasiparticle heterodyne mixing in SIS tunnel junctions
P. L. Richards, T. M. Shen, R. E. Harris, and F. L. Lloyd
The rapid onset of quasiparitcle tunneling current in superconductor-insulator-superconductor (Josephson) junctions at voltages above 2Delta/e is being used for millimeter-wave heterodyne mixing. Junctions with a 2-[mu]m diameter and R=50 Omega have little capacitive shunting at the signal frequency ... [Appl. Phys. Lett. 34, 345 (2008)] published Thu Aug 7, 2008.
A high-intensity scanning ion probe with submicrometer spot size
R. L. Seliger, J. W. Ward, V. Wang, and R. L. Kubena
A liquid-metal gallium-ion source was imaged by unity-magnification single-gap accelerating lens with a postlens deflector to form a focused scanning probe. We report the dependence of the probe diameter and probe current on the lens acceptance half-angle. The results range between probe diameters o ... [Appl. Phys. Lett. 34, 310 (2008)] published Thu Aug 7, 2008.
The technology of solid-fuel-layer targets for laser-fusion experiments
D. L. Musinski, T. M. Henderson, T. R. Pattinson, and J. A. Tarvin
An apparatus which produces uniform solid-fuel layers in glass-shell targets for laser irradiation is described. A low-power cw laser pulse is used to vaporize the fuel within a previously frozen target which is maintained in a cold-helium environment by a cryogenic shroud. The rapid refreezing that ... [Appl. Phys. Lett. 34, 300 (2008)] published Thu Aug 7, 2008.
A new technique for fabricating cryogenic laser-fusion targets using cold-gas jets
K. Kim, B. J. Smoot, R. L. Woerner, and C. D. Hendricks
A new technique of fabricating a uniform layer of solid DT inside a glass microshell has been developed using a heater-wirecold-gas-jets combination. A D-filled glass microsphere was continuously cooled by two cold-helium-gas jets, and a controlled amount of current was pulsed through a heater wire ... [Appl. Phys. Lett. 34, 282 (2008)] published Thu Aug 7, 2008.
Isolation of type-2 magnetic contrast in the SEM by a lock-in technique
Oliver C. Wells
The backscattered electron (BSE) signal in the scanning electron microscope (SEM) can be modulated, under the proper experimental conditions, by magnetic fields inside the specimen. This modulation is typically less than 1% of the collected current, and this must be amplified so as to be clearly vis ... [Appl. Phys. Lett. 35, 644 (2008)] published Thu Aug 7, 2008.
A new sensitive microwave bolometer heterodyne receiver
G. Nimtz, B. Schlicht, H. Lehmann, and E. Tyssen
Some narrow-gap mixed crystal semiconductors show a magnetic field induced transport anomaly at low temperatures. The anomaly is accompanied by a transition from a low to a high resistivity state, which in turn causes a strongly nonlinear I-V characteristic. We have investigated microwave mixing nea ... [Appl. Phys. Lett. 35, 640 (2008)] published Thu Aug 7, 2008.
The importance of geometry, field, and temperature in tunneling and rectification behavior of point contact junctions of identical metals
N. M. Miskovsky, S. J. Shepherd, P. H. Cutler, T. E. Sullivan, and A. A. Lucas
This letter presents new results on the tunneling and rectification characteristics of metal-whisker point-contact diodes. The model adopted here includes two new important effects, namely, the actual geometrical asymmetry of the electrodes and a temperature differential between tip and base. Calcul ... [Appl. Phys. Lett. 35, 560 (2008)] published Thu Aug 7, 2008.
Helmholtz resonance cells for pulsed dye laser-excited high resolution optoacoustic spectroscopy
Robert W. Shaw
The signal waveform observed in optoacoustic measurements is complex and highly dependent on sample for open-cavity cells and pulsed optical excitation. A Helmholtz resonator (HR) cell has been employed to reduce this dependence on sample and thus simplify signal processing. The cell background sign ... [Appl. Phys. Lett. 35, 253 (2008)] published Thu Aug 7, 2008.
State-of-the-art performance of GaAlAs/GaAs avalanche photodiodes
H. D. Law, K. Nakano, and L. R. Tomasetta
GaAlAs/GaAs avalanche photodiodes have been successfully fabricated. The performance of these detectors is characterized by a rise time of less than 35 ps, an external quantum efficiency with an antireflection coating of 95% at 0.53 [mu]m, and a microwave optical gain of 42 dB. The dark current dens ... [Appl. Phys. Lett. 35, 180 (2008)] published Thu Aug 7, 2008.
Electron bombardment effect on the breakdown voltage of Zener diodes
T. Tomimasu
The nature of electron irradiation-induced changes in the avalanche breakdown voltage has been investigated for Zener diodes with breakdown voltages from 5.6 to 25.5 V. Their breakdown-voltage change is proportional to the irradiation electron fluence and inversely proportional to the impurity gradi ... [Appl. Phys. Lett. 35, 65 (2008)] published Thu Aug 7, 2008.
Microsecond operation of a general purpose pulsed proton gun
S. Humphries, Jr. and G. W. Kuswa
A magnetically insulated pulsed proton gun is described that provides an extracted parallel beam of annular cross section for microsecond pulse lengths. In initial tests, time-averaged currents of 5 kA and current densities of 50 A/cm were achieved with <~200 kV voltage. The behavior of the gun appe ... [Appl. Phys. Lett. 35, 13 (2008)] published Thu Aug 7, 2008.
Shuttle instability induced by an ac gate in a nanoelectromechanical single-electron transistor
Norihiko Nishiguchi
We theoretically investigate shuttle instability induced by an ac gate in a nanoelectromechanical single-electron transistor containing a moveable grain. The ac gate causes periodic variations of charge on the grain, which turn (in the bias field) to driving force of grain vibrations. The forced gra ... [Phys. Rev. B 78, 085407 (2008)] published Wed Aug 6, 2008.
Synthesis of horizontally aligned ZnO nanowires localized at terrace edges and application for high sensitivity gas sensor
J. Y. Son, S. J. Lim, J. H. Cho, W. K. Seong, and Hyungjun Kim
We developed step edge decoration method for the fabrication of semiconductor ZnO nanodots and nanowires using pulsed laser deposition. We synthesized high quality ZnO nanowires with the small diameter of about 20 nm and the uniform interval of about 80 nm between each nanowire, which has a simple ... [Appl. Phys. Lett. 93, 053109 (2008)] published Wed Aug 6, 2008.
Separation modes in microcontacts identified by the rate dependence of the pull-off force
L. Chen, N. E. McGruer, G. G. Adams, and Y. Du
We report the observation of two distinct modes of rate-dependent behavior during contact cycling tests. One is a higher pull-off force at low cycling rates and the other is a higher pull-off force at high cycling rates. Subsequent investigation of these contacts using scanning electron microscopy ( ... [Appl. Phys. Lett. 93, 053503 (2008)] published Wed Aug 6, 2008.
Electrical feedthrough for gas pressures up to 10 000 bar and low temperatures
J. A. Schouten, N. J. Trappeniers, and W. Goedegebuure
An electrical gas-tight feedthrough is described which is suitable for use at pressures up to 10 000 bar and temperatures down to 180 degrees C. The capacitance of the feedthrough is about 20 pF. ... [Rev. Sci. Instrum. 50, 1652 (2008)] published Wed Aug 6, 2008.
Fast new technique for measuring the resonance frequencies of high Q systems
Carlo Cosmelli and Sergio Frasca
A technique for measuring the resonance frequencies of an aluminum bar (used as a gravitational antenna) with high accuracy is presented. This method is based on the positive feedback of the bar, and is much faster than the others commonly in use. ... [Rev. Sci. Instrum. 50, 1650 (2008)] published Wed Aug 6, 2008.
Simple and economical capacitive displacement system for UHV operation
Robert Chow and William A. Tiller
A parallel plate capacitor was assembled as a displacement transducer for operation in an UHV environment. The capacitive displacement system was linear over a 2.5 [mu]m range with a resolution of 0.051 [mu]m. Components in the electric circuit were common laboratory instruments. ... [Rev. Sci. Instrum. 50, 1649 (2008)] published Wed Aug 6, 2008.
Instrument for measuring tooth mobility
J. L. Smith, A. Wolfenden, and K. Zwaaneveld
An instrument and intraoral mounting have been developed to assess the degree of tooth mobility induced by the wearing of cast-metal partial dentures. The instrument utilized linear instrument bearings and a transducer to record voltage changes when a load of 5 N was applied to the mesial surface of ... [Rev. Sci. Instrum. 50, 1645 (2008)] published Wed Aug 6, 2008.
Stability characteristics of carbon--glass resistance thermometers
L. M. Besley
Six commercial carbonglass resistance thermometers have been subjected to thermal cycling between 15 and 300 K and tested for stability at 15, 20, and 27 K. The results reveal no common mode of behaviour but show the stability of these thermometers is an order of magnitude inferior to that of german ... [Rev. Sci. Instrum. 50, 1626 (2008)] published Wed Aug 6, 2008.
Further laboratory studies and stratospheric flight of a mass spectrometer beam system
K. Mauersberger and R. Finstad
A gas expansion system combined with a mass spectrometer has been tested and flown successfully in the stratosphere. Through a sequence of orifices and high speed pumping, gas particles were formed into a molecular beam and analyzed by a sensitive mass spectrometer. During two balloon flights, verti ... [Rev. Sci. Instrum. 50, 1612 (2008)] published Wed Aug 6, 2008.
Quartz tube orifice leaks for local, fast-response gas sampling to mass spectrometers
B. Kasemo
Simple and versatile quartz tube orifice leaks, suitable for sampling of gas mixtures to mass spectrometers, have been made by heating the tip of a quartz tube in a hydrogenoxygen flame. With these leaks the requirement of expensive and clumsy differential pumping stages is removed. The quartz probe ... [Rev. Sci. Instrum. 50, 1602 (2008)] published Wed Aug 6, 2008.
Properties and operation of a 90[degree] spherical deflector as photoelectron energy analyzer in connection with spin-polarization measurements by Mott scattering
E. Kisker, M. Campagna, W. Gudat, and E. Kuhlmann
We discuss the electron-optical properties of the 90 degrees spherical analyzer. A nearly parallel electron beam which can be extracted from a magnetic photocathode in an external magnetic field under suitable conditions is focused to the exit plane of the analyzer. Electron spin polarization detec ... [Rev. Sci. Instrum. 50, 1598 (2008)] published Wed Aug 6, 2008.
Electrohydraulic fatigue apparatus for testing at cryogenic temperature
P. K. Liaw and J. Baker
A closed-loop electrohydraulic fatigue apparatus was constructed for testing from above room temperature to 77 K. Several important improvements in the electronics of the reference function generator and the servo controller over previous apparatus are described. The electronics allows cool-down of ... [Rev. Sci. Instrum. 50, 1590 (2008)] published Wed Aug 6, 2008.
Magnetization measurements using the field gradient of a high-field solenoid
P. J. Flanders and C. D. Graham
By using a high-field solenoid, the force on a magnetic sample resulting from a field gradient becomes large and measurements using the Faraday (or Curie) method are greatly simplified. By using an electronic analog dividing circuit, curves of magnetic moment or susceptibility versus field or temper ... [Rev. Sci. Instrum. 50, 1564 (2008)] published Wed Aug 6, 2008.
Improved microwave Michelson interferometer operating at 140 GHz
L. Arthur A. Read, I. R. Dagg, and G. E. Reesor
Several major improvements have been made to a Michelson-type microwave interferometer operating at a frequency of 140 GHz. An enlarged dielectric cell, an improved measuring system, and a highly stable microwave system allow a precise determination of the complex dielectric constant for low-loss li ... [Rev. Sci. Instrum. 50, 1553 (2008)] published Wed Aug 6, 2008.
Electro-optical multichannel spectrometer for transient resonance Raman and absorption spectroscopy
K. B. Hansen, R. Wilbrandt, and P. Pagsberg
An optical multichannel system is described, used for time-dependent absorption measurements in the gas phase and the liquid phase and for resonance Raman spectroscopy of short-lived transient species in the liquid phase in pulse radiolysis. It consists of either an image converter streak unit or an ... [Rev. Sci. Instrum. 50, 1532 (2008)] published Wed Aug 6, 2008.
Adjustable phase device for low-frequency NMR experiments
Kurt Weyand, Ernst Simon, and Yoram Leuchter
In order to detect low-level NMR signals by bridge methods, a phase displacing device based on principle of voltage addition has been developed allowing the precise bridge balancing over a one decade frequency range. Using analogous multiplier devices for control and adjust circuit the phase adjustm ... [Rev. Sci. Instrum. 50, 1521 (2008)] published Wed Aug 6, 2008.
Mass analyzer using electron-beam-guiding type ion source
Tohru Kishi, Isao Yamada, and Toshinori Takagi
A mass analyzer having a scanning electron microscopy (SEM) mechanism and using electron beam bombardment vaporization ion source have been submitted. Secondary ions from the surface trapped in the potential well formed by the incident electron beam can be guided into the slit of mass analyzer throu ... [Rev. Sci. Instrum. 50, 1517 (2008)] published Wed Aug 6, 2008.
Effects of high-current input pulses upon Channeltrons
Edward A. Kurz
Experiments are described which detail the response of Channeltrons operated at high gains when exposed to large pulsed inputs. Some temporary gain depression was observed. A hypothesis is presented which describes the observed response. ... [Rev. Sci. Instrum. 50, 1492 (2008)] published Wed Aug 6, 2008.
Novel sample container for solution calorimetry
D. L. Raschella, R. L. Fellows, and J. R. Peterson
A new design for calorimeter sample containers is described. The basic design is a hollow right cylinder with thin, glass membranes covering both ends. The membranes are intended to be broken out completely to release the sample contained within. The membranes are sealed to the container body with s ... [Rev. Sci. Instrum. 50, 1481 (2008)] published Wed Aug 6, 2008.
Cooling of extraction electrode of an ion source in long-pulse operation
H. Horiike, U. Kondoh, H. Morita, H. Shirakata, T. Sugawara et al.
Experimental studies were made on the cooling of extraction electrodes of an ion source in the case of long-pulse operation. Copper electrodes with forced water cooling pipes were tested under the condition that an ion beam of 1 to 5 A at 30 keV was extracted for up to 10 s. The average heat loading ... [Rev. Sci. Instrum. 50, 1453 (2008)] published Wed Aug 6, 2008.
All-metal automated Toepler pump for laboratory use
R. W. Baker, T. L. Buxton, and R. E. Ellefson
An all-metal automated Toepler pump has been developed with improved safety and reliability over the traditional glass pump. New applications cited include the preparation of standard gas mixtures and the transfer of gas for vapor phase reactions. ... [Rev. Sci. Instrum. 50, 1429 (2008)] published Wed Aug 6, 2008.
Linear position-sensitive x-ray detector incorporating a self-scanning photodiode array
Ronald C. Gamble, John D. Baldeschwieler, and Charles E. Giffin
A linear position-sensitive x-ray detector for x-ray spectroscopy and diffraction applications has been tested which can provide excellent spatial resolution, wide dynamic range and good sensitivity. The heart of the system is a self-scanning, photosensitive silicon diode array. It is interfaced via ... [Rev. Sci. Instrum. 50, 1416 (2008)] published Wed Aug 6, 2008.
Instrument combining x-ray photoelectron spectroscopy and secondary ion mass spectrometry for surface studies
R. W. Hewitt, A. T. Shepard, W. E. Baitinger, N. Winograd, and W. N. Delgass
X-ray Photoelectron Spectroscopy (XPS) or (ESCA) and Secondary Ion Mass Spectrometry (SIMS) have been combined in the same ultrahigh vacuum system to facilitate a new approach to studying clean and reacted surfaces. The design philosophy is to connect two satellite vacuum systems via a set of magnet ... [Rev. Sci. Instrum. 50, 1386 (2008)] published Wed Aug 6, 2008.
Cell design for pressure to 25 kbar
Jacques E. Schoutens and Steven S. Senesac
A cell design is presented for experiments with hydrostatic pressures up to 25 kbar. The pressure-transmitting medium around the sample is candle wax, which is sealed in the cavity with molybdenum disulfide impregnated nylon and aluminum disks. This approach showed no detectable leakage to 25 kbar. ... [Rev. Sci. Instrum. 50, 1373 (2008)] published Wed Aug 6, 2008.
Conversion of a Cary 60 spectropolarimeter into a fast circular dichroism instrument for use with standard rapid reaction techniques
H. P. Bachinger, H. P. Eggenberger, and G. Hanisch
The conversion of a Cary 60 spectropolarimeter to a fast circular dichroism instrument (CD) using CD detection for standard rapid reaction techniques and for recording normal CD spectra is described. Although the optical setup remains nearly the same, the electronics are modified to increase the fre ... [Rev. Sci. Instrum. 50, 1367 (2008)] published Wed Aug 6, 2008.
Characteristics of the Berkeley multicusp ion source
K. W. Ehlers and K. N. Leung
The performance of a cubical permanent magnet generated line-cusp ion source has been investigated for use with neutral beam injectors. This source has been operated with discharge currents greater than 500 A and ion current densities higher than 400 mA/cm at the extraction grid. The uniformity of t ... [Rev. Sci. Instrum. 50, 1353 (2008)] published Wed Aug 6, 2008.
Design and properties of a multianode, cylindrical proportional counter for position sensing at high count rates
J. A. Hanson and M. K. Kopp
A cylindrical proportional counter with six anode wires was designed and tested. The electron drift velocity was greater than that of similar single-anode, coaxial proportional counter, thus, allowing counting and position sensing of low-energy photons (<60 keV) at high count rates (>~10 counts/s). ... [Rev. Sci. Instrum. 50, 1318 (2008)] published Wed Aug 6, 2008.
Direct grounding tool for examination of uncoated specimens in the scanning electron microscope
George S. M. Cowan, Jr. and Jack A. Horner
By combining a micromanipulator, a medical cystoscope, and a forked specimen probe, a direct grounding tool for examination of uncoated specimens in the SEM has been developed, tested, and successfully demonstrated. It provides a valuable alternative technique when it is undesirable to coat SEM spec ... [Rev. Sci. Instrum. 50, 1314 (2008)] published Wed Aug 6, 2008.
Automated instrumentation for research on the lingual tactile sensory system
Kal M. Telage
Modifications in lingual vibrotactile instrumentation including programmable stimulus control, signal delivery, and data acquisition are presented. A discussion emphasizes advantages of the system for evaluating children and previews recent experimental procedures. ... [Rev. Sci. Instrum. 50, 1296 (2008)] published Wed Aug 6, 2008.
Mass filter and focusing ion detector for use with time-of-flight velocity distribution measurements
M. D. Burrows, S. R. Ryan, W. E. Lamb, Jr., and L. C. McIntyre, Jr.
A novel mass filter and focusing ion detector for time-of-flight studies of dissociative ionization fragments is described. The filterdector combination is particularly suited for measuring the kinetic energy released in the molecular dissociation process. The mass filter utilizes a computer-control ... [Rev. Sci. Instrum. 50, 1278 (2008)] published Wed Aug 6, 2008.
Photon flux measurements using calorimetry
John Olmsted III
A simple photometric calorimeter has been constructed, consisting of a vacuum-jacketed cell equipped with flat quartz windows to admit incident light, a thermistor probe to monitor temperature change, and a resistance heater for calibration. An optically dense, photochemically inert solution inside ... [Rev. Sci. Instrum. 50, 1256 (2008)] published Wed Aug 6, 2008.
Vidicon-camera parallel-detection system for angle-resolved electron spectroscopy
S. P. Weeks, J. E. Rowe, S. B. Christman, and E. E. Chaban
A multiple-angle, parallel detection scheme for ultraviolet photoemission spectroscopy and LEED has been developed based on a minicomputer-controlled vidicon camera and a LEED-grid energy analyzer. This system allows rapid data acquisition and display so that one can obtain energy spectra over a 70 ... [Rev. Sci. Instrum. 50, 1249 (2008)] published Wed Aug 6, 2008.
Fast, large-signal, free-standing foil bolometer for measuring ultrasoft x-ray burst fluence
James H. Degnan
A fast (~300 ns), large-signal (>~1 V), free-standing foil bolometer was developed for measuring ultrasoft x-ray burst fluences. The results of bolometer measurements of the radiation output of an imploding foil liner plasma indicate yields of several tens of kJ, assuming isotropic emission. This is ... [Rev. Sci. Instrum. 50, 1223 (2008)] published Wed Aug 6, 2008.
Generation of quasistatic magnetic fields
H. C. Praddaude and S. Foner
A prototype switching system has been developed which can switch 20 kA at 230 V furnished by low-voltage dc generators at the National Magnet Laboratory. The energy is used to generate quasistatic magnetic fields in liquid-nitrogen-cooled copper coils for times approaching 1 s. The present arrangeme ... [Rev. Sci. Instrum. 50, 1183 (2008)] published Wed Aug 6, 2008.
Versatile type miniature diamond anvil high-pressure cell
S. Yamaoka, O. Fukunaga, O. Shimomura, and H. Nakazawa
A miniature diamond anvil high-pressure cell 42 mm in diameter, 18 mm thick, and 150 g in weight has been constructed. The cell is loaded into a pistoncylinder type pressing device with an alignment mechanism and compressed to a desired pressure. After the pressure is clamped by three screws, the ce ... [Rev. Sci. Instrum. 50, 1163 (2008)] published Wed Aug 6, 2008.
A neutral beam sciopticon
P. M. Ryan, J. H. Whealton, R. C. Davis, W. L. Stirling, and C. C. Tsai
A sciopticon based on the pinhole-camera effect is being used to determine individual beamlet contributions to the quality of neutral beams extracted from multiaperture ion sources. The technique outlined in this note can be used to study the effects on beam optics of nonhomogeneous source plasma de ... [Rev. Sci. Instrum. 50, 1160 (2008)] published Wed Aug 6, 2008.
Multichannel, direct-reading spectrograph attachment
M. W. P. Cann, J. B. Shin, and R. W. Nicholls
An instrument is described which provides a multichannel direct-reading capability for photoelectric spectrographic detection. The important feature of the instrument is the ability of the user to select at will any combination of channels for position adjustment and to move these while preserving t ... [Rev. Sci. Instrum. 50, 1144 (2008)] published Wed Aug 6, 2008.
A high-temperature and high-field nuclear magnetic resonance instrument
D. Ploumbidis
In the course of constructing an apparatus suitable for studies of nuclear magnetic resonance at high tempertures and high fields we developed a furnace with a new heating element which has been applied for the first time to NMR studies. The furnace can work in a 8-T field of a superconducting magne ... [Rev. Sci. Instrum. 50, 1133 (2008)] published Wed Aug 6, 2008.
Microwave radiometer blackbody calibration standard for use at millimeter wavelengths
P. F. Goldsmith, R. A. Kot, and R. S. Iwasaki
We describe a high-temperature reference load designed for calibration of microwave radiometers at frequencies of 80150 GHz. An effective temperature of 410 K and a power reflection coefficient of less than 5 x 10 have been measured at frequencies between 85 and 95 GHz. ... [Rev. Sci. Instrum. 50, 1120 (2008)] published Wed Aug 6, 2008.
High-pressure stopped-flow apparatus up to 3 kbar
Muneo Sasaki, Fujitsugu Amita, and Jiro Osugi
A high-pressure stopped-flow apparatus was constructed which could be operative at hydrostatic pressures up to 3 kbar. Some preparative results on anionic sigma-complex formation reactions are presented up to 1.5 kbar between 2,4,6-trinitrobenzene (I) and hydroxide ion and between compound (I) and s ... [Rev. Sci. Instrum. 50, 1104 (2008)] published Wed Aug 6, 2008.
A compound carbon thermometer for the temperature range 0.3--100 K
A. Adolf, H. Djerassi, and J. Leszczyszyn
A compound carbon thermometer consisting of an abreast connection of a carbon Speer resistor and a carbon Allen-Bradley resistor was tested in the temperature interval 0.3100 K, an interval which generally requires two independent resistors to be covered. The characteristics, sensitivity, and analyt ... [Rev. Sci. Instrum. 50, 1101 (2008)] published Wed Aug 6, 2008.
Low-distortion resistive anodes for two-dimensional position-sensitive MCP systems
M. Lampton and C. W. Carlson
Microchannel plates (MCPs) are frequently employed with resistive anodes to detect charged particles or photons and yield analog signals from which event positions can be decoded. We discuss an anode geometry devised by C.W. Gear that offers theoretically distortionless encoding of Cartesian event p ... [Rev. Sci. Instrum. 50, 1093 (2008)] published Wed Aug 6, 2008.
A nanosecond temperature-jump apparatus for high pressures
Klaus G. Liphard
An apparatus is described which extends the time range of the temperature-jump technique at high pressures to the nanosecond region. A temperature increase of a few degrees can be obtained within approximately 50 ns by discharging a high-voltage coaxial cable. Reactions are followed spectrophotometr ... [Rev. Sci. Instrum. 50, 1089 (2008)] published Wed Aug 6, 2008.
Highly-reliable temperature sensor using rf-sputtered SiC thin film
Kiyotaka Wasa, Takao Tohda, Yukio Kasahara, and Shigeru Hayakawa
A SiC thin-film thermistor for high-temperature use has been developed by using rf-sputtered SiC thin films. This thermistor can be used for industrial and consumer use within an operating temperature range of 100 to 450 degrees C. By using SiC thin films, the thermistor maintains high electrical s ... [Rev. Sci. Instrum. 50, 1084 (2008)] published Wed Aug 6, 2008.
A convenient method for the measurement of species composition from an intense neutral beam
R. R. Smith and J. W. Stearns
We present a method to infer the approximate species mixture of neutral beam sources which accelerate positive hydrogen ions. An idealized neutral beam is specified by the accelerating voltage, the neutralizer thickness (molecules of hydrogen per cm), and the currents of extracted H, H, and H. These ... [Rev. Sci. Instrum. 50, 1070 (2008)] published Wed Aug 6, 2008.
High-intensity carbon ion injector
S. Humphries, Jr., C. W. Mendel, Jr., G. W. Kuswa, and S. A. Goldstein
An injector of intense beams of carbon ions is described. The device uses an array of carbon plasma guns to inject ions directly into a magnetically insulated acceleration gap. Ion currents exceed 3 kA with beam energies between 100 and 300 keV (for C) and 200 and 600 keV (for C) over a 700-ns pulse ... [Rev. Sci. Instrum. 50, 993 (2008)] published Wed Aug 6, 2008.
Recent studies of float and stall curves in controlled-clearance deadweight testers with a simple piston
D. H. Newhall, I. Ogawa, and V. Zilberstein
The effect of piston rotation speed and fluid viscosity on the performance of free-piston gauges with a controlled clearance was studied as part of an experimental program aiming at the better evaluation of pressure by these primary pressure standards. Calculated effective area is shown to be greatl ... [Rev. Sci. Instrum. 50, 964 (2008)] published Wed Aug 6, 2008.
Glass windows for hydrostatic pressures of 45 kbar
A. Lavergne and E. Whalley
Unprotected glass windows can be used at hydrostatic pressures up to at least 45 kbar on a 0.5-mm-diam aperture, and up to 40 kbar on a 0.8-mm-diam aperture. ... [Rev. Sci. Instrum. 50, 962 (2008)] published Wed Aug 6, 2008.
Precision axial translator with high stability
M. A. Bosch
We describe a new type of translator which is inherently stable against torsion and twisting. This concentric translator is also ideally suited for precise axial motion with clearance of the center line. ... [Rev. Sci. Instrum. 50, 1024 (2008)] published Wed Aug 6, 2008.
Long-lived rotating targets
A. Picot
The target used inside an accelerator, even if rotating, is damaged by the beam and must be frequently replaced. We describe a simple method permitting the use of a rotating target over its full area, and improving its life by a factor of 10. ... [Rev. Sci. Instrum. 50, 1021 (2008)] published Wed Aug 6, 2008.
Absolute pressure measurements and analysis of diamonds subjected to maximum static pressures of 1.3--1.7 Mbar
H. K. Mao, P. M. Bell, K. J. Dunn, R. M. Chrenko, and R. C. DeVries
Force per unit area measurements made in the megabar pressure cell, independently of other pressure calibration systems, are consistent with the ruby R scale of Mao, Bell, Shaner, and Steinberg and its extrapolation to 1.4 Mbar. Physical analysis of diamond anvils removed after experiments to maximu ... [Rev. Sci. Instrum. 50, 1002 (2008)] published Wed Aug 6, 2008.
Method of forming an inexpensive high-temperature metal foil seal
Mau-Song Chou and Gerald A. Zawadzkas
A method for forming a thin metal foil seal capable of withstanding temperatures up to 500 degrees C and pressures up to 150 psig has been developed. The seal is formed by seam welding with an inexpensive electric marker. ... [Rev. Sci. Instrum. 50, 923 (2008)] published Wed Aug 6, 2008.
Shock tube coupled to the time-of-flight mass spectrometer via a molecular beam sampling system
I. Krizancic, M. Haluk, S. H. Cho, and O. Trass
A method for continuous mass spectrometric analysis of high-temperature reacting gas mixtures is described. The apparatus consists of a unique combination of three devices: the shock tube, the time-of-flight mass spectrometer, and the supersonic molecular beam. The driven section of the shock tube c ... [Rev. Sci. Instrum. 50, 909 (2008)] published Wed Aug 6, 2008.
Application of direct current comparator apparatus in combustion calorimetry
Ria Jochems, Harm Dekker, and Cornelis Mosselman
A method was developed for the application of direct current comparator apparatus in resistance thermometry and in voltage measurements in combustion calorimetry. The performance of the measuring system was checked by combustions of benzoic acid combined with electrical calibration of the calorimete ... [Rev. Sci. Instrum. 50, 859 (2008)] published Wed Aug 6, 2008.
Portable optical particle (0.06 mu m) counter
Kyo Suda and Takashi Handa
An improved portable optical counter, using a HeNe laser with 8 mW output, measures particles ranging in size from 0.06 to 10 [mu]m in diameter in situ. ... [Rev. Sci. Instrum. 50, 831 (2008)] published Wed Aug 6, 2008.
Reduction of spurious baseline effects in NMR
Daniel C. Abbas
The practical limitation on sensitivity in broad-line NMR is frequently spurious effects on the baseline rather than the masking of the signal by thermal noise. I discuss some of the causes of spurious baseline effects and describe a simple circuit used to reduce them by a factor of 300. ... [Rev. Sci. Instrum. 50, 829 (2008)] published Wed Aug 6, 2008.
Submicrometer particle detector and size analyzer
C. D. Litton, L. Graybeal, and M. Hertzberg
A new instrument is described for measuring concentrations of submicrometer particulates with diameters ranging from 0.005 to 1.0 [mu]m and concentrations as low as 750 particles per cm at small diameters and 25 particles per cm at the larger diameters. Developed by the Bureau of Mines, the instrume ... [Rev. Sci. Instrum. 50, 817 (2008)] published Wed Aug 6, 2008.
Production of centrifugal fields greater than 100 million times gravity
Rintaro Katano and Sakae Shimizu
A high-speed rotation instrument to produce centrifugal fields greater than 100 million times gravity has been constructed. Small, solid, spherical high-carbon chromium steel rotors are suspended magnetically in high vacuum and spun by a rotating magnetic field. It is found that the spinning rotor e ... [Rev. Sci. Instrum. 50, 805 (2008)] published Wed Aug 6, 2008.
Simple partial pressure measurement of SF[sub 6] in mixtures with nitrogen
J. M. Marks
A simple but accurate method for the measurement of the partial pressure of SF gas in mixtures with nitrogen is described. It is based on the ease with which the gases can be separated by freezing the SF. ... [Rev. Sci. Instrum. 50, 790 (2008)] published Wed Aug 6, 2008.
Spurious pulse rejection in a photon correlation experiment
Robert Walraven and Yin Yeh
A method has been developed to significantly suppress the effect of spurious pulses on the correlation spectrum in photon correlation experiments. When the correlation experiment is operated at a low count rate (<2 true pulses per total measured correlation time), the circuit rejects an incoming pul ... [Rev. Sci. Instrum. 50, 780 (2008)] published Wed Aug 6, 2008.
High-intensity x-ray diffraction apparatus for pressures up to 100 kilobars and temperatures down to 1.5 K
E. Thorwarth and M. Dietrich
A high-pressure diamond anvil pressure technique for x-ray structure investigations at temperatures down to 1.5 K is described. An energy dispersive method in conjunction with a newly developed conical x-ray shutter brings maximum intensity to the adjacent germanium detector. Superconductivity is de ... [Rev. Sci. Instrum. 50, 768 (2008)] published Wed Aug 6, 2008.
New type of stepping motor control for fast beam scraper
H. Ishimaru and Z. Igarashi
A stepping motor control for a fast beam scraper in high vacuum is described. High speed (5 degrees /ms) and smooth angular velocity are obtained by using inertia motion within 270 degrees in one revolution. ... [Rev. Sci. Instrum. 50, 757 (2008)] published Wed Aug 6, 2008.
Shielding of longitudinal magnetic fields with thin, closely spaced, concentric cylinders of high permeability material
D. U. Gubser, S. A. Wolf, and J. E. Cox
Formulae for the longitudinal shielding effectiveness of N thin, closely spaced, concentric cylinders of high permeability material have been developed and experimentally tested. For shields which cannot be oriented, or which change their orientation in the ambient field, the shielding effectiveness ... [Rev. Sci. Instrum. 50, 751 (2008)] published Wed Aug 6, 2008.
Effects of 1-MeV gamma radiation on a multi-anode microchannel array detector tube
J. G. Timothy and R. L. Bybee
The response of a multi-anode microchannel array (MAMA) detector tube to 1-MeV gamma radiation from a Co source was evaluated. The measured detection efficiency of the microchannel plate (MCP) was 2.2 x 10 counts/photon and no permanent degradation of MCP performance was observed after exposure to ... [Rev. Sci. Instrum. 50, 743 (2008)] published Wed Aug 6, 2008.
Improved servo-polarimeter
William Primak and Emmet Monahan
A servo-polarimeter utilizing a rotating plastic film as a modulator has been modified to improve stability and sensitivity. The birefringence in a sample being scanned by moving it past a slit can now be determined to better than 3 x 10. ... [Rev. Sci. Instrum. 50, 738 (2008)] published Wed Aug 6, 2008.
Lexan coating to eliminate the UV sensitivity of soft x-ray proportional counters with a polypropylene window
D. G. Fabricant, R. E. Goddard, F. R. Harnden, Jr., and P. Gorenstein
Lexan coatings on polypropylene windows can eliminate the UV sensitivity of soft x-ray proportional counters. A method is described for coating thin polypropylene films by dipping into and withdrawing from a volatile solution containing Lexan. The x-ray absorption of a typical Lexan coating was only ... [Rev. Sci. Instrum. 50, 727 (2008)] published Wed Aug 6, 2008.
Linear induction accelerators made from pulse-line cavities with external pulse injection
Ian Smith
Two types of linear induction accelerator have been reported previously. In one, unidirectional voltage pulses are generated outside the accelerator and injected into the accelerator cavity modules, which contain ferromagnetic material to reduce energy losses in the form of currents induced, in para ... [Rev. Sci. Instrum. 50, 714 (2008)] published Wed Aug 6, 2008.
Qualitative and quantitative flow visualization technique using ozone
R. R. Dickerson and D. H. Stedman
We have developed a new flow-visualization technique based on the absorption of ultraviolet light by ozone. Ozone is an excellent tracer, because as a gas it has the same effective physical properties as air. Ozone strongly absorbs the principal line (253.7 nm) of a mercury lamp, epsilon=310 (atm cm ... [Rev. Sci. Instrum. 50, 705 (2008)] published Wed Aug 6, 2008.
Cold-stage microscopy system for fast-frozen liquids
Yeshayahu Talmon, H. Ted Davis, L. E. Scriven, and Edwin L. Thomas
The least artifact-laden fixation technique for examining colloidal suspensions, microemulsions, and other microstructured liquids in the electron microscope appears to be thermal fixation, i.e., ultrafast freezing of the liquid specimen. For rapid-enough cooling and for observation in TEM/STEM a th ... [Rev. Sci. Instrum. 50, 698 (2008)] published Wed Aug 6, 2008.
Digital, synchronously timed control system for pulsed ion cyclotron resonance mass spectrometry
R. J. Dugan, L. N. Morgenthaler, R. O. Daubach, and J. R. Eyler
An integrated control system for a pulsed ion cyclotron resonance (ICR) mass spectrometer has been designed, constructed, and put into operation. It utilizes a crystal clock oscillator to accurately control the delay and width of the various pulses necessary for pulsed ICR operation. A switched inte ... [Rev. Sci. Instrum. 50, 691 (2008)] published Wed Aug 6, 2008.
Phase measurement using an interferometer having a filamentary spatial filter and an extended source of polychromatic light
Sadahiko Mori
The theory of phase measurement by means of the interferometer using a filamentary spatial filter (IFSF) is extended to the case in which the source has finite width. Experimental results satisfactorily coincide with theoretically obtained characteristics. The examination of accuracy suggests that t ... [Rev. Sci. Instrum. 50, 685 (2008)] published Wed Aug 6, 2008.
Bridge for measurement of low resistance
J. R. Matey, S. B. Dierker, and A. C. Anderson
A simple four-terminal bridge of low power dissipation and high resolution is used to measure small resistances at low temperatures. ... [Rev. Sci. Instrum. 50, 671 (2008)] published Wed Aug 6, 2008.
Improved grid holders for an all-purpose electron microscope specimen stage
C. E. Warble
The general requirements necessary for a specimen grid holder (cup) to meet the rather stringent demands set by an all-purpose specimen stage are discussed. Two models made from platinum or aluminum are described, which provide for the grid to be either on or off the axes of tilt, and allow the cup ... [Rev. Sci. Instrum. 50, 669 (2008)] published Wed Aug 6, 2008.
Double-pendulum vibration isolator with three-dimensional isolation
Paul Lorrain
This isolator is an improved version of one that was described recently in this journal. It consists of a platform suspended by three springs, the damping being provided by a much smaller mass, suspended from the platform by a spring and damped in an oil bath. This simple device is a highly effectiv ... [Rev. Sci. Instrum. 50, 664 (2008)] published Wed Aug 6, 2008.
Simple helium cryostat for Raman spectroscopy
R. D. Kirby and J. R. Duffey
We describe a simple and inexpensive flowing gas helium cryostat which efficiently cools the surface of a sample and eliminates the need for good thermal contact between the sample and a substrate. ... [Rev. Sci. Instrum. 50, 663 (2008)] published Wed Aug 6, 2008.
Apparatus for sectioning diffusion specimens in liquid nitrogen
Raoul Weil, David Lazarus, and Frank Witt
Details are given on the design and operation of an apparatus which enables sectioning of samples in a liquid nitrogen bath. The sectioning of samples, in which a radioactive tracer has been diffused, is made by abrasion. ... [Rev. Sci. Instrum. 50, 642 (2008)] published Wed Aug 6, 2008.
High-pressure apparatus for dielectric measurements in high frequency
Bui Ai, D. Lebarbier, Hoang The Giam, J. C. Bapt, and M. Farzaneh
The present article describes an experimental apparatus for the measurement of low-loss dielectric material under conditions of high pressures (maximum pressure 1500 bars) and high frequencies (115 MHz.) The measurements of these losses are based on the classical method of the Q-meter with a general ... [Rev. Sci. Instrum. 50, 625 (2008)] published Wed Aug 6, 2008.
PdPtAu alloys for low-temperature precision resistors
J. F. March and F. Thurley
Palladium-rich PdPt and PdAu alloys exhibit a resistancetemperature behavior characterized by flat minima even after eliminating the Kondo effect by oxidation of the impurities. The opposite signs of their thermoelectric potentials against a superconductor permit the preparation of ternary PdPtAu al ... [Rev. Sci. Instrum. 50, 616 (2008)] published Wed Aug 6, 2008.
Alternative methods for determining the electrical conductivity of core samples
R. J. Lytle, A. G. Duba, and J. L. Willows
Electrode configurations are described that can be used in measuring the electrical conductivity of a core sample and that do not require access to the core end faces. The use of these configurations eliminates the need for machining the core ends for placement of end electrodes. This is because the ... [Rev. Sci. Instrum. 50, 611 (2008)] published Wed Aug 6, 2008.
Hall measurements to 40 kilobars under hydrostatic pressure in a piston-cylinder device
N. Lifshitz and R. G. Maines
A technique for Hall measurements under truly hydrostatic pressures to 40 kilobars is described. The method employs the piston-cylinder apparatus with a Teflon cell to contain a suitable fluid. The necessary magnetic field is generated by a coil placed inside the cell. Hall data can be obtained over ... [Rev. Sci. Instrum. 50, 608 (2008)] published Wed Aug 6, 2008.
Contactless technique for the measurement of electrical resistivity in anisotropic materials
C. Zeller, A. Denenstein, and G. M. T. Foley
Measurement of basal plane electrical resistivities in quasi-two-dimensional materials by conventional four-point bridge techniques is extremely difficult. In making measurements of room temperature basal plane resistivities in highly conducting highly anisotropic synthetic metals we have developed ... [Rev. Sci. Instrum. 50, 602 (2008)] published Wed Aug 6, 2008.
K-band high-pressure cell for ENDOR studies
R. K. Wu, T. F. Dutton, and W. T. Doyle
This article describes a versatile high-pressure K-band EPRENDOR system, designed for the examination of the effects of hydrostatic pressure on F-center hyperfine interactions. Dielectric filling is used to minimize the inner dimensions of the pressure cell. Cavity mode and coil geometry permit the ... [Rev. Sci. Instrum. 50, 590 (2008)] published Wed Aug 6, 2008.
20-kilobar pressure system
R. K. Wu, T. F. Dutton, and W. T. Doyle
A reciprocating hand pump capable of generating hydrostatic pressure to 20 kilobars has been constructed for high-pressure magnetic resonance studies. The pump body and the high-pressure cell are two separate units, which are connected by a high-pressure tubing using connectors modified from a desig ... [Rev. Sci. Instrum. 50, 586 (2008)] published Wed Aug 6, 2008.
High-pass photocathode x-ray ionization chamber for surface EXAFS
N. J. Shevchik and D. A. Fischer
An x-ray detector that collects electrons emitted from a cathode plate and amplifies them through field intensified ionization in helium gas is described. The sensitivity of the detector to the photon frequency increases by nearly an order of magnitude as the photon energy exceeds the absorption edg ... [Rev. Sci. Instrum. 50, 577 (2008)] published Wed Aug 6, 2008.
Microprocessor-controlled inhalation system for repeated exposure of animals to aerosols
R. L. Carpenter, F. P. Barr, R. L. Leydig, and R. E. Rajala
A microprocessor-controlled inhalation exposure system (MCIES) has been built to automate aerosol generation and sampling while controlling exposure time for animal toxicity studies. The system has a time resolution of 0.1 s and automatically sequences the exposure events from initiation to teminati ... [Rev. Sci. Instrum. 50, 560 (2008)] published Wed Aug 6, 2008.
Momemtum transmission of a diaphragmed magnetic spectrometer: II. First-order calculations
G. Sanna and M. Donnetti
On the basis of the analysis developed in Part I and of the definitions therein introduced, a procedure for the calculation in the Gaussian approximation of the integral quantities characterizing the momentum transmission of a magnetic spectrometer is carried out. Such procedure applies both to symm ... [Rev. Sci. Instrum. 50, 553 (2008)] published Wed Aug 6, 2008.
Momentum transmission of a diaphragmed magnetic spectrometer: I. Analysis and definitions
G. Sanna and M. Donnetti
An experimental device consisting of a plane source of charged particles and of a magnetic spectrometer equipped with horizontal and vertical diaphragms is considered. An analysis intended to achieve an exact analytical expression to connect the observed particle flux to the source emission and spec ... [Rev. Sci. Instrum. 50, 544 (2008)] published Wed Aug 6, 2008.
Uniform stress conditions in the diamond anvil cell at 200 kilobars
J. M. Besson and J. P. Pinceaux
Pressure gradients in a diamond anvil cell have been measured with a 4:1 methanol:ethanol mixture as a pressure medium up to 350 kilobars. When pressure is applied rapidly, stress gradients are shown to be negligible up to 200 kilobars and probably above. With this procedure it is possible to signif ... [Rev. Sci. Instrum. 50, 541 (2008)] published Wed Aug 6, 2008.
Precision field averaging NMR magnetometer for low and high fields, using flowing water
J. M. Pendlebury, K. Smith, P. Unsworth, G. L. Greene, and W. Mampe
The separated oscillatory field magnetic resonance technique (Ramsey technique) has been employed with flowing water as a volume averaging magnetometer. Polarization and detection were performed in high fields, external to the volume over which the magnetic field was to be averaged. An accuracy of a ... [Rev. Sci. Instrum. 50, 535 (2008)] published Wed Aug 6, 2008.
Simple, reliable, and sensitive interferometer for the measurement of the refractive index of liquids as a function of temperature
D. Beysens
We describe a very simple and inexpensive interferometer setup which provides high accuracy measurements of the refractive index (n) of liquids with temperature. A standard deviation sigma (n) =5.4 x 10 has been observed in isooctane liquid when fitting n to a linear temperature variation. ... [Rev. Sci. Instrum. 50, 509 (2008)] published Wed Aug 6, 2008.
100-MHz noise spectrometer
R. Rzemien, C. K. Iddings, and W. F. Love
The design, construction, and performance of a 100-MHz noise spectrometer are described. Basically a 100-MHz bridge, this system uses the properties of a double balanced mixer to enable the experimenter to determine spectral densities of fluctuations in the real or imaginary parts of a sample impeda ... [Rev. Sci. Instrum. 50, 488 (2008)] published Wed Aug 6, 2008.
Use of variable p[sub H] interface to a mass spectrometer for the measurement of dissolved volatile compounds
James C. Weaver and Jerome H. Abrams
A wide variety of dissolved chemicals can be measured continuously with some specificity by directly interfacing a relatively inexpensive mass spectrometer to a solution. Specifically, we describe the construction and initial use of a membrane interace to a mass spectrometer which allows the continu ... [Rev. Sci. Instrum. 50, 478 (2008)] published Wed Aug 6, 2008.
[sup 6]Li-loaded liquid scintillators with pulse shape discrimination
L. R. Greenwood, N. R. Chellew, and G. A. Zarwell
Excellent pulse height and pulse shape discrimination performance has been obtained for liquid scintillators containing as much as 10 wt.% Li-salicylate dissolved in a toluene-methanol solvent system using naphthalene and 9,10 diphenylanthracene as intermediate and secondary solutes. This solution h ... [Rev. Sci. Instrum. 50, 472 (2008)] published Wed Aug 6, 2008.
Improved [sup 10]B-loaded liquid scintillator with pulse-shape discrimination
L. R. Greenwood and N. R. Chellew
An improved B-loaded liquid scintillator solution has been developed containing trimethylborate, 1-methylnaphthalene, and 9,10-diphenylanthracene. Cells up to 5 cm in diameter by 15.2 cm long have been prepared and tested with B-loadings up to 7.2% by weight (80% trimethylborate). The solution has e ... [Rev. Sci. Instrum. 50, 466 (2008)] published Wed Aug 6, 2008.
New beam postion monitor by detecting wall currents
Kohtaro Satoh
A new type of beam postion monitor has been designed and bench tested. The results agreed well with the expected performance. Tests with the proton beam showed that this monitor was applicable to our accelerator. ... [Rev. Sci. Instrum. 50, 450 (2008)] published Wed Aug 6, 2008.
Programmable digital pulse generator for proton enhanced [sup 13]C high resolution NMR in solids
J. W. M. van Os and W. S. Veeman
A programmable pulse generator is described for NMR spectrometers. The pulse generator can operate either in a single cycle mode where up to 16 pulses can be given sequentially or, in the double cycle mode, a programmable number (<=15) of these pulses can be repeated n times (n<=99) before the rest ... [Rev. Sci. Instrum. 50, 445 (2008)] published Wed Aug 6, 2008.
Extension of the application of the shorted quartz gauge
Gideon Rosenberg
Shorted guard-ring quartz gauges 12.7 mm in diameter and 3.2 mm thick were shock loaded by AL 6061 and copper impactors to stresses of 42 and 58 kilobars, respectively. Distortion of the current output was observed only at the 58 kilobar stress; at 42 kilobars the current profile conforms closely to ... [Rev. Sci. Instrum. 50, 442 (2008)] published Wed Aug 6, 2008.
New difference reflectance methods for study of small interfacial effects
Edward D. Huber and S. O. Sari
Two sensitive differential optical techniques useful for study of small reflectance or absorptive differences between two interfaces are described. The first scheme employs a mechanically chopped light beam impinging on an arrangement of symmetrical dual cells to allow detection of differential refl ... [Rev. Sci. Instrum. 50, 438 (2008)] published Wed Aug 6, 2008.
Cylindrical crossed-coil NMR limb blood flowmeter
R. E. Halbach, J. H. Battocletti, A. Sances, Jr., R. L. Bowman, and V. Kudravcev
A nuclear magnetic resonance (NMR) flowmeter has been developed for noninvasive measurement of upper extremity blood flow in humans. Flow through major arteries and veins is determined by placing the arm into a 12.5-cm i.d. crossed-coil detector structure, contained in a 0.075 T (750 G) steady detec ... [Rev. Sci. Instrum. 50, 428 (2008)] published Wed Aug 6, 2008.
ESR dual sample cavities for Q-band and for spectrometers with small magnets
W. Froncisz
Dual sample cavities are described in which the standard sample sees both the primary modulation field and also an opposing secondary modulation field from a very small adjacent compensation coil. Both primary and secondary fields are at the same modulation frequency. The geometry permits solution o ... [Rev. Sci. Instrum. 50, 425 (2008)] published Wed Aug 6, 2008.
High-resolution scanning transmission electron microscope at Johns Hopkins
J. W. Wiggins, J. A. Zubin, and M. Beer
The scanning transmission electron microscope constructed at Johns Hopkins follows the general layout of the first instrument at the University of Chicago. It is currently operating at 50 kV with a resolution of about 3 A. Its detector scheme consists of scintillation crystals coupled to photomultip ... [Rev. Sci. Instrum. 50, 403 (2008)] published Wed Aug 6, 2008.
High temperature [sup 1]H NMR probe
D. S. Webster, L. F. Cross, and L. J. Lynch
A furnace is described which is suitable for single coil proton magnetic resonance experiments from room temperature to 1100 K, and which will fit a 30 mm magnet gap. The temperature variation is less than K at 800 K over a 27 mm-long sample. ... [Rev. Sci. Instrum. 50, 390 (2008)] published Wed Aug 6, 2008.
Simple bridge detector for use with a low-temperature capacitance thermometer, and thermometer performance limits
D. E. Prober
A simple high-resolution bridge circuit for use with a glassceramic capacitance thermometer is described. This circuit allows a linear readout of capacitance changes and has better than 1 mK resolution and short-term stability. Performance limits of the thermometer itself are also reported. Irreprod ... [Rev. Sci. Instrum. 50, 387 (2008)] published Wed Aug 6, 2008.
Circuit for maintaining constant phototube current in polarization modulation spectroscopy
F. A. Modine
A description is given of a control circuit that maintains a constant direct current from a photomultiplier tube. The circuit is useful in spectroscopic applications employing ligh modulation at high frequencies. ... [Rev. Sci. Instrum. 50, 386 (2008)] published Wed Aug 6, 2008.
RC-encoding for position-sensitive proportional counters using low-resistance, metal-wire anode and active load capacitance
M. K. Kopp
We developed a feedback-stabilized, active load-capacitance to use low-resistance, metal-wire anodes in RC-line encoded, position-sensitive proportional counters (PSPCs) of any length. A 12-cm-long experimental PSPC was tested using a 12-[mu]m-diam Nichrome wire anode and an ~21 pF active load capac ... [Rev. Sci. Instrum. 50, 382 (2008)] published Wed Aug 6, 2008.
Computer automation of data acquisition from a Knudsen, torsion-effusion pendulum
Jimmie G. Edwards, Mark K. Heckler, and H. Bradford Thompson
A computer-automated data acquistion system has been developed for a dynamic torsion pendulum applied to measurement of vapor pressures at high temperatures by the torsion-effusion method. Laser beams reflected from mirrors on the pendulum are detected by a bank of photodetectors which, in turn, tra ... [Rev. Sci. Instrum. 50, 374 (2008)] published Wed Aug 6, 2008.
Modified SCR for optically actuated triggering
W. W. Rice, R. C. Oldenborg, F. B. Wampler, and D. F. Milligan
A simple inexpensive, optically actuated triggering device (optical trigger) has been developed for synchronizing pulsed lasers with signal gathering instrumentation. The heart of this device is a commercially available SCR that has been modified for light activated operation. The optical trigger de ... [Rev. Sci. Instrum. 50, 364 (2008)] published Wed Aug 6, 2008.
Nearly on-line picosecond streak camera diagnostics of the cw mode-locked YAG laser radiation
K. Hamal, V. Krajicek, V. Kubecek, A. Novotny, M. Vrbova et al.
An image-converter streak camera incorporating a TV video-recording system interfaced to a computer HP 2100 was used to record and instantly display the processed shape of a picosecond laser pulse. The output versus input exposure response curve linearity of the whole system was verified over a dyna ... [Rev. Sci. Instrum. 50, 337 (2008)] published Wed Aug 6, 2008.
Soft x-ray appearance potential spectroscopy with a channelplate detector
Richard S. Withers and R. N. Lee
A soft x-ray appearance potential spectrometer using a channelplate detector is described and evaluated. This detector is much more sensitive than the metal photocathode in common usage and provides useful SXAPS spectra at primary electron currents of less than 10 [mu]A. Operation of the detector at ... [Rev. Sci. Instrum. 50, 326 (2008)] published Wed Aug 6, 2008.
High-resolution magnetic field measurement system for recording heads and disks
C. D. Lustig, A. W. Baird, W. F. Chaurette, H. Minden, W. T. Maloney et al.
A high-resolution system for measuring the magnetic fields near recording heads and disks has been built. The perpendicular field components close to the head and disk surfaces are measured with an InSb Hall probe which is moved point-by-point under computer control. The computer also records the ma ... [Rev. Sci. Instrum. 50, 321 (2008)] published Wed Aug 6, 2008.
Comparison of circuits for linearizing the temperature indications of thermistors
Harold J. Hoge
Eight circuits designed for producing a signal that is a linear function of temperature change, utilizing a single thermistor as the temperature-sensitive element, are examined. All are found equal in linearizing capability, including five circuits containing operational amplifiers. This finding doe ... [Rev. Sci. Instrum. 50, 316 (2008)] published Wed Aug 6, 2008.
Pressure apparatus of split-octahedron type for x-ray diffraction studies
Akihito Ohtani, Akifumi Onodera, and Naoto Kawai
An apparatus of split-octahedron type has been developed for the study of x-ray diffraction at high pressure. The apparatus consists of a cylinder, a sphere, and an octahedron, all split up and assembled in a multistaged arrangement. Three ways of splitting the innermost octahedron are utilized in m ... [Rev. Sci. Instrum. 50, 308 (2008)] published Wed Aug 6, 2008.
Heat capacity measurements by means of thermal relaxation method in medium temperature range
Ichiro Hatta
The thermal relaxation method is used to measure heat capacities of small samples in the temperature range around room temperature. The calorimeter is designed to measure under heat exchange gas and a steplike excess heat is applied to the sample by irradiation from a lamp. ... [Rev. Sci. Instrum. 50, 292 (2008)] published Wed Aug 6, 2008.
Versatile four-probe ac conductivity measurement system
Terry E. Phillips, James R. Anderson, Charles J. Schramm, and Brian M. Hoffman
The design of a four-probe ac conductivity measurement system is described. The system is capable of making precision conductance measurements from 10 to 10 S at 20 to 200 Hz. Driven coaxial shields and a controlled current source are utilized to eliminate phase shift/attenuation errors, and make th ... [Rev. Sci. Instrum. 50, 263 (2008)] published Wed Aug 6, 2008.
Compact low-temperature fixed point device
M. Steinback, D. Matsumoto, and A. C. Anderson
A small fixed point device is designed to be permanently mounted on a dilution refrigerator. The device contains Be and In samples with transitions at about 25 mK and 3.4 K. ... [Rev. Sci. Instrum. 50, 260 (2008)] published Wed Aug 6, 2008.
Temperature control of a tungsten incadescent lamp
Charles G. Masi
A thermostatic control for a tungsten incadescent lamp is described. The circuit employs an operational amplifier feedback circuit to adjust the filament current and thereby achieve a constant filament temperature. The filament temperature is adjustable over a wide range by adjusting a potentimeter. ... [Rev. Sci. Instrum. 50, 257 (2008)] published Wed Aug 6, 2008.
Screw-fastened joints for thermal contact at low temperatures
K. M. Lau and W. Zimmermann, Jr.
Electrical resistance measurements at 4.2 K on simple screw-fastened joints between two pieces of bare copper, between two pieces of gold-plated copper, and between two pieces of silver indicate the potential usefulness of such joints for thermal contact down to millikelvin temperatures. ... [Rev. Sci. Instrum. 50, 254 (2008)] published Wed Aug 6, 2008.
New fully bakeable and moveable vacuum seal between stainless steel and Al[sub 2]O[sub 3] ceramic
M. Langenwalter, M. Grossl, and T. D. Mark
The current paper describes a simple construction which allows the monitoring of the radial dependence of the extracted and mass identified ion currents in a hollow cathode stationary afterglow apparatus at any time during the afterglow. The main feature of the monitoring device is a fully bakeable ... [Rev. Sci. Instrum. 50, 253 (2008)] published Wed Aug 6, 2008.
Control of ultralow pressures: an absolute thermodynamic manometer
Peter Taborek and David Goodstein
A method of accurately manipulating the pressure of helium gas in the range P=10 to 10 Torr, T<5 K is presented. The method requires only a very modest apparatus and makes use of thermodynamic measurements on the HeGrafoil system. A calibration curve and a pressure scale for the manometer are develo ... [Rev. Sci. Instrum. 50, 227 (2008)] published Wed Aug 6, 2008.
Bremsstrahlung isochromat spectroscopy using a modified XPS apparatus
J. K. Lang and Y. Baer
The new components required for bremsstrahlung isochromat spectroscopy (BIS) in UHV (10 Torr range) have been developed and incorporated into an x-ray photoelectron spectrometer. They consist of a Pierce electron gun and a soft x-ray photon detector, both of which have to fulfill precise geometrical ... [Rev. Sci. Instrum. 50, 221 (2008)] published Wed Aug 6, 2008.
Single photon x-ray detection with a CCD image sensor
R. C. Catura and R. C. Smithson
Individual x rays of 5.9 and 22.4 keV have been detected and energy analyzed in single pixels of a CCD image sensor. The results indicate the CCD operates as an array of tiny Si solid state detectors providing both high spatial resolution and x-ray energy discrimination. These devices will prove use ... [Rev. Sci. Instrum. 50, 219 (2008)] published Wed Aug 6, 2008.
Simple sensitive capacitance manometer for corrosive gas laser systems
S. Shammas and H. J. J. Seguin
The design and performance of a capacitance manometer for use in corrosive gas laser environments is presented. This simple and inexpensive isolating device can be quickly fabricated in any machine shop, and permits the utilization of ordinary non-passivated pressure measurement apparatus or gauges ... [Rev. Sci. Instrum. 50, 207 (2008)] published Wed Aug 6, 2008.
Experimental study of ion beam optics in a two-stage accelerator
Jinchoon Kim, W. L. Gardner, and M. M. Menon
Hydrogen ion beam optics in a two-stage linear acceleration system is studied by examining the beam divergence as a function of the voltage and gap distribution, the beam perveance, the background gas pressure, the aspect ratio, and the total accelerating energy (60-110 keV). The system consists of ... [Rev. Sci. Instrum. 50, 201 (2008)] published Wed Aug 6, 2008.
Fast recovery, high sensitivity NMR probe and preamplifier for low frequencies
D. I. Hoult
The design of a probe-preamplifier combination which reduces the NMR receiver recovery time following a pulse by a factor of at least twenty at 5 MHz is described. The preamplifier, which has a noise figure of 1.3 dB, employs negative feedback to damp the probe coil (a typical effective Q is 7), but ... [Rev. Sci. Instrum. 50, 193 (2008)] published Wed Aug 6, 2008.
Variable resolution capability for multichannel filter spectrometers
P. S. Henry
In this paper we describe a new electronic instrument called a spectrum expander, which is a two-port digital signal-processing device whose output power spectrum S(Ef) is (approximately) a frequency-expanded replica of its input spectrum S(f): S(Ef) [approximate]S(f), where E is the expansion ratio ... [Rev. Sci. Instrum. 50, 185 (2008)] published Wed Aug 6, 2008.
Electronic stabilization system for an oscillating vane pressure gauge
D. W. Hainsworth and F. H. Dyksterhuis
An electronic stabilization system for an oscillating vane pressure gauge is described. A new continuous drive method is used, obviating the necessity for reliance on mechanical filtering by the vane to produce stable oscillation amplitude. The parameter, damping coefficient, can be measured as bein ... [Rev. Sci. Instrum. 50, 181 (2008)] published Wed Aug 6, 2008.
Wide energy range mass spectrograph
P. Wagli
The design and construction of a mass spectrograph, for the diagnostics of fast pulsed sources, is described. It is intended particularly for measurements on laser generated plasma. The special features of the instrument are a broad energy passband (E/E=5) and simultaneous energy independent mass-fo ... [Rev. Sci. Instrum. 50, 165 (2008)] published Wed Aug 6, 2008.
Noise reduction in EPR discharge-flow studies
G. J. Diebold and D. L. McFadden
In discharge-flow systems employing electron paramagnetic resonance detection, intense spectrometer noise is present under certain conditions. This noise is due to free electrons produced in the discharge and can be eliminated by the addition of an electron scavenger to the flow. Using SF to suppres ... [Rev. Sci. Instrum. 50, 157 (2008)] published Wed Aug 6, 2008.
Self-triggered channel ion source
C. Bouchard and J. D. Carette
An ion source made from a continuous dynode electron multiplier of the straight channel type and an ion reflector device is described. Its principle of operation is based on a continuous self-sustained ion and electron cascade in the multiplier channel. Operating characteristics and the analysis of ... [Rev. Sci. Instrum. 50, 99 (2008)] published Wed Aug 6, 2008.
Simple, high current, antimony ion source
Hideo Sugiura
A simple metal ion source capable of producing a continuous, uncontaminated, high current beam of Sb ions is presented. It produced a total ion current of 200 [mu]A at 1 kV extraction voltage. A discharge occurred in the source at a pressure of 6 x 10 Torr. The ion current extracted from the source ... [Rev. Sci. Instrum. 50, 84 (2008)] published Wed Aug 6, 2008.
Synchronous modulation in scanning Auger electron microscopy
K. Goto, S. Ichimura, and R. Shimizu
The modulation frequency on the cylindrical mirror analyzer of a scanning Auger microscope has been synchronized to the digital scanning system. This technique allows one to obtain an Auger image free from moire patterns which arise from the beat between scanning and modulation frequencies, and perm ... [Rev. Sci. Instrum. 50, 46 (2008)] published Wed Aug 6, 2008.
High-energy spectrophotometer for rapid constituent analysis in the range of 0.25--2.4 mu m
Isaac Landa
This publication describes a constituent analyzer which uses a concave holographic grating for high-energy throughput, a conjugate cam drive to allow up to ten spectral scans per second, a microprocessor for data gathering and system control, and a minicomputer for the complex statistical computatio ... [Rev. Sci. Instrum. 50, 34 (2008)] published Wed Aug 6, 2008.
X-ray magnifier
William J. Boettinger, Harold E. Burdette, and Masao Kuriyama
A method for the magnification of x-ray radiographic images is described and demonstrated. This magnifier employs two successive asymmetric diffractions of an x-ray beam from highly perfect silicon crystals. The two diffractions magnify the beam in two perpendicular directions. A device with a magni ... [Rev. Sci. Instrum. 50, 26 (2008)] published Wed Aug 6, 2008.
Temperature inhomogeneity in the glass mixing chamber of a [sup 3]He/[sup 4]He dilution refrigerator
Masafumi Kumano, Yusaku Ikegami, Takashi Sato, and Shinhachiro Saito
The temperature inhomogeneity in the glass mixing chamber of a He/He dilution refrigerator has been studied. The inhomogeneity is reduced to 10 mK by inserting a cylindrical spacer in the mixing chamber. ... [Rev. Sci. Instrum. 50, 24 (2008)] published Wed Aug 6, 2008.
Infrared optical sensor for measuring internal interfacial wave motions
C. G. Koop, H. Rungaldier, and J. D. Sherman
The absorption of infrared energy is used to infer internal interfacial displacements. The probe consists of an infrared emitting diode, operated in a pulsed mode, which projects a collimated beam of radiation across a fluid interface onto a silicon photodiode detector. The output of the diode feeds ... [Rev. Sci. Instrum. 50, 20 (2008)] published Wed Aug 6, 2008.
Expandable flash x-ray tube (FXT) having a 0.5-mm source size
Y. Carmel and S. Eylon
An inexpensive, expandable, continuously pumped, all-metal flash x-ray tube (FXT) was developed. It was coaxialy integrated at the end of a 70-Omega flexible coaxial transmission line. The tube, which has a small, 0.5-mm, x-ray source size when operated at 200 kV, produces a dose rate of 5 x 10 R/s ... [Rev. Sci. Instrum. 50, 17 (2008)] published Wed Aug 6, 2008.
Atom and Ion Sources, by L. Valyi. Reviewer
K. Prelec
... [Rev. Sci. Instrum. 50, 137 (2008)] published Wed Aug 6, 2008.
Preparation of micron thick specimens for high pressure study
Mool C. Gupta and Arthur L. Ruoff
The electrical resistance behavior of a material under very high pressure can be studied by pressing the material with a diamond indentor against a diamond flat. The high pressures generated can be calculated using Hertz's theory provided the material thickness is about a micron or less. Here we des ... [Rev. Sci. Instrum. 50, 135 (2008)] published Wed Aug 6, 2008.
Preparation and purity measurement of extremely pure helium gas
J. T. Yates, Jr, J. J. Zinck, and W. H. Weinberg
A procedure is described for the production, storage, and handling of very pure helium gas and for the measurement of its purity in the part per 10 range. ... [Rev. Sci. Instrum. 50, 132 (2008)] published Wed Aug 6, 2008.
Vacuum-sealed specimen stage for scanning microscopy of air-sensitive materials
John Steger and Jack Alonzo
A vacuum-sealed specimen stage for investigation of air-sensitive materials has been designed. This stage is useful for instruments equipped with a vacuum antechamber and allows facile sample mounting in a dry box or glove bag. The sample cell is subsequently introduced into the antechamber of the i ... [Rev. Sci. Instrum. 50, 130 (2008)] published Wed Aug 6, 2008.
High-temperature dilatometer system for measuring the shrinkage kinetics of a liquid-containing ceramic system
R. D. Sandison and C. L. Eggerding
A dilatometer system usable to 1600 degrees C in atmospheres varying from oxidizing to reducing, with or without controlled dew points, is described. The system was optimized to measure the shrinkage of a liquid-containing ceramic material without causing deformation by viscous creep. Shrinkages up ... [Rev. Sci. Instrum. 50, 129 (2008)] published Wed Aug 6, 2008.
Ratio of analog pulse height module for fluorescence activated cell sorter
G. E. Johnson, B. P. Dorman, and F. H. Ruddle
We describe a simple and inexpensive circuit for producing output pulses of amplitude proportional to the ratio of analog pulse height (RAPH) inputs. Use of a diode to limit negative output excursions results in simplified design and is found to be suitable for Fluorescence Activated Cell Sorter (FA ... [Rev. Sci. Instrum. 50, 109 (2008)] published Wed Aug 6, 2008.
''Ad hoc'' liquid spray vacuum leak detection method
W. Fiszdon
The common method of spreading volatile liquid on vacuum systems to check for leaks is reexamined. Simple experiments are made to determine the parameter that characterizes the effectiveness of candidate liquids. It is found that the most important properties are density and viscosity, not vapor pre ... [Phys. Fluids 22, 1829 (2008)] published Wed Aug 6, 2008.
Investigation of p-GaAsSb as a THz Emitter
S. Hargreaves, L. J. Bignell, R. A. Lewis, D. Schoenherr, M. Saglam et al.
Our purpose was to determine if GaAsSb might be made to emit THz-frequency electromagnetic radiation. Our result is that, with a suitable electric field imposed and under illumination by ultrashort pulses of near-infrared radiation, GaAsSb indeed emits THz radiation. To the best of our knowledge thi ... [J. Electrochem. Soc. 155, H734 (2008)] published Tue Aug 5, 2008.
Indirect measurement of the magnetocaloric effect using a novel differential scanning calorimeter with magnetic field
S. Jeppesen, S. Linderoth, N. Pryds, L. Theil Kuhn, and J. Buch Jensen
A simple and high-sensitivity differential scanning calorimeter (DSC) unit operating under magnetic field has been built for indirect determination of the magnetocaloric effect. The principle of the measuring unit in the calorimeter is based on Peltier elements as heat flow sensors. The high sensiti ... [Rev. Sci. Instrum. 79, 083901 (2008)] published Tue Aug 5, 2008.
Design and characterization of a thermal hydrogen atom source
K. G. Tschersich, J. P. Fleischhauer, and H. Schuler
The hydrogen atom source considered here incorporates a hot capillary fed by hydrogen gas. Our earlier measurements on a source heated by electron bombardment are interpreted in terms of a simple model which encourages us to design a source heated by the radiation from a filament. The radiatively he ... [J. Appl. Phys. 104, 034908 (2008)] published Tue Aug 5, 2008.
Improvement of a dynamic scanning force microscope for highest resolution imaging in ultrahigh vacuum
S. Torbrugge, J. Lubbe, L. Troger, M. Cranney, T. Eguchi et al.
We report on a modification of a commercial scanning force microscope (Omicron UHV AFM/STM) operated in noncontact mode (NC-AFM) at room temperature in ultrahigh vacuum yielding a decrease in the spectral noise density from 2757 to 272 fm/sqrt(Hz). The major part of the noise reduction is achieved ... [Rev. Sci. Instrum. 79, 083701 (2008)] published Mon Aug 4, 2008.
Fixed Structure Feedforward Controller Design Exploiting Iterative Trials: Application to a Wafer Stage and a Desktop Printer
Stan H. van der Meulen, Rob L. Tousain, and Okko H. Bosgra
In this paper, the feedforward controller design problem for high-precision electromechanical servo systems that execute finite time tasks is addressed. The presented procedure combines the selection of the fixed structure of the feedforward controller and the optimization of the controller paramete ... [J. Dyn. Sys., Meas., Control 130, 051006 (2008)] published Mon Aug 4, 2008.
Evidence for neutron production in deuterium gas with a pyroelectric crystal without tip
W. Tornow, S. M. Shafroth, and J. D. Brownridge
We present evidence for the production of H(d,n)He neutrons in gaseous deuterium by using a pyroelectric crystal as positive ion accelerator. In contrast to previous studies, neutrons were generated without a tip attached to the crystal and without using a solid deuterated target. The deuterium gas ... [J. Appl. Phys. 104, 034905 (2008)] published Mon Aug 4, 2008.
Calibration of charge state conversion surfaces for neutral particle detectors
P. Wahlstrom, J. A. Scheer, P. Wurz, E. Hertzberg, and S. A. Fuselier
Molecular oxygen and hydrogen ions were scattered off hydrogen terminated diamondlike carbon (DLC) charge state conversion surfaces at incident grazing angles. The energy range of the scattered particles was 3901000 eV, and the surface roughness of the DLC surface was of the order of 1 A rms. For a ... [J. Appl. Phys. 104, 034503 (2008)] published Fri Aug 1, 2008.
Terahertz generation in an actively controlled femtosecond enhancement cavity
M. Theuer, D. Molter, K. Maki, C. Otani, J. A. L'huillier et al.
We report on terahertz generation by Cherenkov-type optical rectification in lithium niobate using an actively controlled femtosecond pumped enhancement cavity. In this way a much higher pump power is available inside the cavity and an increased terahertz output power is obtained. The advantages of ... [Appl. Phys. Lett. 93, 041119 (2008)] published Fri Aug 1, 2008.
A new scanning tunneling microscope reactor used for high-pressure and high-temperature catalysis studies
Feng Tao, David Tang, Miquel Salmeron, and Gabor A. Somorjai
We present the design and performance of a homebuilt high-pressure and high-temperature reactor equipped with a high-resolution scanning tunneling microscope (STM) for catalytic studies. In this design, the STM body, sample, and tip are placed in a small high pressure reactor (~19 cm) located withi ... [Rev. Sci. Instrum. 79, 084101 (2008)] published Fri Aug 1, 2008.
Pressure transmitting medium Daphne 7474 solidifying at 3.7 GPa at room temperature
Keizo Murata, Keiichi Yokogawa, Harukazu Yoshino, Stefan Klotz, Pascal Munsch et al.
A pressure transmitting medium named Daphne 7474, which solidifies at P=3.7 GPa at room temperature, is presented. The value of P increases almost linearly with temperature up to 6.7 GPa at 100 degrees C. The high pressure realized by a medium at the liquid state allows a higher limit of pressuriz ... [Rev. Sci. Instrum. 79, 085101 (2008)] published Fri Aug 1, 2008.
Accurate and quick calibration method for polarization-modulation spectroscopy using an ac-modulated polarizing undulator
Masahito Tanaka, Kazutoshi Yagi-Watanabe, Fusae Kaneko, and Kazumichi Nakagawa
An accurate calibration method in which an ac-modulated polarizing undulator is used for polarization modulation spectroscopy such as circular dichroism (CD) and linear dichroism (LD) has been proposed and successfully applied to vacuum ultraviolet (vuv) CD and LD spectra measured at beamline BL-5B ... [Rev. Sci. Instrum. 79, 083102 (2008)] published Fri Aug 1, 2008.
A pressure cell for nonresonant inelastic x-ray scattering studies of gas phases
M. Minzer, J. A. Bradley, R. Musgrave, G. T. Seidler, and A. Skilton
We report the design and performance of a gas-phase sample cell for measurements of momentum transfer (q) dependent nonresonant inelastic x-ray scattering (NRIXS). NRIXS measurements from He gas at 2 MPa (20 bars) readily demonstrate dipole-allowed and dipole-forbidden final states for two-electron ... [Rev. Sci. Instrum. 79, 086101 (2008)] published Fri Aug 1, 2008.
Performance of a Ge-microstrip imaging detector and polarimeter
U. Spillmann, H. Brauning, S. Hess, H. Beyer, Th. Stohlker et al.
Using 98% linearly polarized radiation at the European Synchrotron Radiation Facility in Grenoble, the performance of a prototype two-dimensional microstrip Ge(i) detector for x-ray imaging and as a Compton polarimeter has been evaluated. Using the energy and position sensitivity of the detector, th ... [Rev. Sci. Instrum. 79, 083101 (2008)] published Fri Aug 1, 2008.
Photonic Time Stretch Enhanced Recording Scope. (arXiv:0808.1020v1 [physics.ins-det])
ePrint arXiv http://arXiv.org/