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Nov 1985

Volume 56, Issue 11, pp. 1995-2178

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Characterization of growing thin films by in situ ellipsometry, spectral reflectance and transmittance measurements, and ion‐scattering spectroscopy

R. P. Netterfield, P. J. Martin, W. G. Sainty, R. M. Duffy, and C. G. Pacey

Rev. Sci. Instrum. 56, 1995 (1985); http://dx.doi.org/10.1063/1.1138408 (9 pages) | Cited 19 times

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A versatile ultrahigh‐vacuum thin‐film deposition and analysis system is described. Films are deposited by electron beam evaporation with the possibility of ion beam bombardment of the growing film. Measurements of the reflectance and/or transmittance of the coating surface can be made simultaneously at 16 wavelengths across the visible or infrared spectrum. Ellipsometric measurements can also be made in situ, at a single wavelength and single angle of incidence, by an ellipsometer which can operate in either an automatic rotating analyzer mode or a manual nulling mode. The system is also equipped with an ion gun producing a submillimeter spot, and with a hemispherical sector, ion energy analyzer for ion scattering spectroscopy studies of the film surface. Results obtained during the deposition of a gold film are presented to demonstrate the capability of the system.
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81.15.-z Methods of deposition of films and coatings; film growth and epitaxy
78.66.Bz Metals and metallic alloys
68.60.-p Physical properties of thin films, nonelectronic
68.55.-a Thin film structure and morphology

Total automation of static and dynamic light scattering experiments with the aid of a special purpose robot

A. M. Ganz and B. E. Boeger

Rev. Sci. Instrum. 56, 2004 (1985); http://dx.doi.org/10.1063/1.1138409 (14 pages) | Cited 4 times

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A fully automated laser light scattering apparatus has been built and is now operational. A specially designed robot moves samples from a thermostatted holding rack to the spectrometer water bath. Use of a smoothly operating robot enables the study of multiphase fluids without disturbing sensitive interfaces. A computer controls virtually all the supporting hardware. Laser input intensity is adjusted by a rotating polarizer and the scattering angle is varied by a stepper motor built into the goniometer. Fiber optics and a silicon photodetector are employed to determine incident and transmitted intensity. Variables such as time base and prescaling on the autocorrelator are optimized by the software according to the characteristics of the sample. Safety and verification procedures are described. The trade off in signal‐to‐noise requirements of both dynamic and classical light scattering are considered in order to enable simultaneous dynamic and classical intensity measurements. An example of the utility of the instrument for studying critical phenomena is given.
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07.60.-j Optical instruments and equipment
07.05.-t Computers in experimental physics
89.20.Bb Industrial and technological research and development

An all solid‐state magnetic switching exciter for pumping excimer lasers

Tsutomu Shimada, Minoru Obara, and Akira Noguchi

Rev. Sci. Instrum. 56, 2018 (1985); http://dx.doi.org/10.1063/1.1138410 (3 pages) | Cited 9 times

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A thyristor, silicon controlled rectifier (SCR), switched multistage magnetic pulse compressor has been successfully developed for KrF excimer laser excitation. Being composed entirely of solid‐state elements, this exciter will provide the extremely long lifetime at high repetition rate operation that cannot be realized by a conventional power supply with a discharge switch.
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42.60.By Design of specific laser systems
84.70.+p High-current and high-voltage technology: power systems; power transmission lines and cables
84.32.Dd Connectors, relays, and switches
85.70.-w Magnetic devices

Pulsed operation of a segmented longitudinal discharge CO2 laser without ballast impedance

L. M. Kukreja, S. K. Sehgal, and U. K. Chatterjee

Rev. Sci. Instrum. 56, 2021 (1985); http://dx.doi.org/10.1063/1.1138411 (4 pages) | Cited 3 times

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It is shown that a longitudinal CO2 laser with two discharge tubes electrically coupled in parallel can be operated in pulsed mode without ballast impedance. This scheme not only yields much higher efficiency (up to 13% at the maximum output energy) and eliminates component failure at high pulse repetition frequency (prf) but also facilitates short pulse availability. In the absence of ballast, current and laser pulse width decrease on increasing the voltage applied to the discharge tubes but these quantities remain unaffected on varying the value of the energy storage capacitor. This enables an independent control of the laser pulse duration and energy. Threshold energy for the onset of nonuniformities in the glow discharge reduces almost exponentially on increasing the discharge current pulse duration but rises on decreasing the operating value of E/N, the electric field to neutral gas density ratio. The maximum output laser energy of about 1 J/pulse, adjustable pulse duration from 30 μs to about 2 ms, and prf up to 50 Hz have been obtained.
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42.55.Lt Gas lasers including excimer and metal-vapor lasers
42.60.By Design of specific laser systems
52.80.Hc Glow; corona

Laser Doppler velocimetry using polarization‐preserving optical fibers for simultaneous measurement of multidimensional velocity components

Noboru Nakatani, Muneo Tokita, Takao Izumi, and Tomoharu Yamada

Rev. Sci. Instrum. 56, 2025 (1985); http://dx.doi.org/10.1063/1.1138412 (5 pages) | Cited 6 times

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Laser Doppler velocimeter (LDV) systems using polarization‐preserving optical fibers are developed by the polarization and the color methods for simultaneous measurement of multidimensional velocity components. By the use of fibers the construction of the optical systems are made easy, the systems are made more flexible, and remote measurement is realized. A signal processor for the LDVs is developed using only a single frequency counter, a high‐speed electronic scanner, and a computer. Using Karman vortex flow and turbulent premixed flame, it is demonstrated that these systems are powerful tools for fluid mechanic measurements.
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47.80.-v Instrumentation and measurement methods in fluid dynamics
42.81.-i Fiber optics
42.62.-b Laser applications
07.05.Hd Data acquisition: hardware and software
07.05.Kf Data analysis: algorithms and implementation; data management
07.05.Rm Data presentation and visualization: algorithms and implementation

Sodium atom distribution within a heat sandwich oven

M. A. Cappelli, P. G. Cardinal, H. Herchen, and R. M. Measures

Rev. Sci. Instrum. 56, 2030 (1985); http://dx.doi.org/10.1063/1.1138413 (8 pages) | Cited 3 times

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In a heat sandwich oven the metal vapor is confined to be disk shaped and is optically accessible through 360° in the plane of the disk. We have used this feature to optically measure the radial atom density distribution of sodium vapor within this type of oven, under a range of conditions. In particular, we have observed the formation of a donut‐shaped atom density distribution when the heat sandwich oven is operated at high temperatures with an under pressure of the argon buffer gas.
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07.77.-n Atomic, molecular, and charged-particle sources and detectors
37.20.+j Atomic and molecular beam sources and techniques
07.20.Hy Furnaces; heaters

Characteristics of a piezoelectric pulsed nozzle beam

P. Andresen, M. Faubel, D. Haeusler, G. Kraft, H.‐W. Luelf, and J. G. Skofronick

Rev. Sci. Instrum. 56, 2038 (1985); http://dx.doi.org/10.1063/1.1138414 (5 pages) | Cited 22 times

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The characteristics of a molecular beam from a piezoelectric pulsed nozzle source are given and, where appropriate, compared to a continuous beam. These include variation during the pulse in the relative intensity and speed ratio for the gases He, Ar, Ne, and N2. The measurements were made by standard time‐of‐flight and laser‐induced fluorescence techniques. For gas valve pulses of time duration less than 500 μs, there was a single peak during which the gases reached continuum steady flow behavior. Typical speed ratios (parallel temperatures) for the gases He, Ar, Ne, and N2 were 19, 34, 34, and 20 (2.1, 0.7, 0.7, and 1.9 K), respectively. These values are comparable to those from a continuous source with equivalent values of p0d, the product of source pressure and nozzle diameter. The dimer concentrations for Ne and Ar were also measured and found to be 0.4% and 0.7%, respectively. A major problem with the valve was its inability to open fully because of the limited motion of the piezoelectric element.
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07.77.-n Atomic, molecular, and charged-particle sources and detectors

Data acquisition and processing: A systems approach

Edward Sternin

Rev. Sci. Instrum. 56, 2043 (1985); http://dx.doi.org/10.1063/1.1138415 (7 pages) | Cited 16 times

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A new nuclear magnetic resonance (NMR) data acquisition and processing system is described. Designed at a fraction of the cost of most commercially available systems, it in many ways exceeds their capabilities. The use of state‐of‐the‐art components in an open‐architecture system where each component is relatively loosely coupled to the rest of the system and thus can be chosen, upgraded, or replaced without major changes to other components, provides for a flexible and expandable system. The principle of incorporating sufficient intelligence into each of the system components allows the use of serial protocols for all noncritical intrasystem communications, simplifying the task of system integration and reducing cost. Such ‘‘unbundling’’ of the hardware also results in a superior adherence to industry standards at the level of individual components. While the technical details are directed primarily at the NMR researchers, a number of general considerations and the description of the principles and criteria used in designing a laboratory data system are of general interest.
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07.05.Hd Data acquisition: hardware and software
07.05.Kf Data analysis: algorithms and implementation; data management
07.05.Rm Data presentation and visualization: algorithms and implementation
07.05.Bx Computer systems: hardware, operating systems, computer languages, and utilities
07.57.Pt Submillimeter wave, microwave and radiowave spectrometers; magnetic resonance spectrometers, auxiliary equipment, and techniques

Application of a microwave preamplifier to an ESR spectrometer

Günter Grampp

Rev. Sci. Instrum. 56, 2050 (1985); http://dx.doi.org/10.1063/1.1138416 (2 pages) | Cited 8 times

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The aim of this investigation was to measure the sensitivity improvement reached on a commercial homodyne X‐band ESR spectrometer by installing a microwave GaAs–FET type preamplifier (8.5–9.6 GHz). Up to a power level of 1 mW a factor of 3 was obtained in signal improvement. Saturation occurred near 30 mW. Both theoretical and experimental results were described and discussed. In addition, a circuit diagram for easy installation of the microwave preamplifier was given.
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07.57.Pt Submillimeter wave, microwave and radiowave spectrometers; magnetic resonance spectrometers, auxiliary equipment, and techniques
84.30.Le Amplifiers
07.50.Ek Circuits and circuit components
85.30.Tv Field effect devices

X‐ray characterization of thin films using a Read camera—An improvement

S. B. Qadri, E. J. Cukauskas, and E. R. Carpenter

Rev. Sci. Instrum. 56, 2052 (1985); http://dx.doi.org/10.1063/1.1138417 (3 pages) | Cited 2 times

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An improvement to the modified Debye–Scherrer camera is described which allows for the accurate determination of the lattice parameter for thin films. The x‐ray collimator assembly has been altered to allow the thin film sample to cut the x‐ray beam in half at zero angle of incidence resulting in a ‘‘D’’ spot on the x‐ray film. The lattice parameter of an aluminum film was measured using this modified camera and compared with that determined by an x‐ray diffractometer scan and the published value. The results agree within 3 mÅ. An additional method using difference angles is also described which can be employed when the origin has not been determined.
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61.05.C- X-ray diffraction and scattering
68.55.-a Thin film structure and morphology
07.85.-m X- and γ-ray instruments

Versatile X‐UV spectrogoniometer with multilayer interference mirrors

M. Arbaoui, J. M. André, P. Couillaux, and R. Barchewitz

Rev. Sci. Instrum. 56, 2055 (1985); http://dx.doi.org/10.1063/1.1138418 (4 pages) | Cited 15 times

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A versatile X‐UV spectrogoniometer based on a modular system is described. The heart of the apparatus is a computer‐controlled θ‐2θ goniometer with 1.8 arcs θ angular resolution. This main unit can be connected to with a (+1, −1) double‐crystal premonochromator and a double‐mirror high‐frequency rejector. The dispersive performance of a multilayer interference mirror (MIM) and a lead stearate pseudocrystal are compared at three wavelengths: 13.3 Å (Cu‐Lα), 44.8 Å (C‐Kα), and 67.7 Å (B‐Kα). The MIM appears as a useful dispersing device for a low resolution flat ‘‘one‐crystal’’ spectrometer in this spectral region.
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07.78.+s Electron, positron, and ion microscopes; electron diffractometers
07.60.Rd Visible and ultraviolet spectrometers
07.10.-h Mechanical instruments and equipment

Compact acoustic levitation device for studies in fluid dynamics and material science in the laboratory and microgravity

E. H. Trinh

Rev. Sci. Instrum. 56, 2059 (1985); http://dx.doi.org/10.1063/1.1138419 (7 pages) | Cited 68 times

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An ultrasonic levitation device operable in both ordinary ground‐based as well as in potential space‐borne laboratories is described together with its various applications in the fields of fluid dynamics, material science, and light scattering. Some of the phenomena which can be studied by this instrument include surface waves on freely suspended liquids, the variations of the surface tension with temperature and contamination, the deep undercooling of materials with the temperature variations of their density and viscosity, and finally some of the optical diffraction properties of transparent substances.
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43.35.Yb Ultrasonic instrumentation and measurement techniques
47.80.-v Instrumentation and measurement methods in fluid dynamics
07.60.-j Optical instruments and equipment

Photoemission from single electrodynamically levitated microparticles

S. Arnold and N. Hessel

Rev. Sci. Instrum. 56, 2066 (1985); http://dx.doi.org/10.1063/1.1138420 (4 pages) | Cited 31 times

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See Also: Erratum

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A simple method for determining the ionization potential from a single electrodynamically levitated microparticle is discussed. The associated spectrometer is described and measurements from graphite and transpolyacetylene are demonstrated.
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07.78.+s Electron, positron, and ion microscopes; electron diffractometers
79.60.-i Photoemission and photoelectron spectra

Simple instrument for the measurement of photoelectron structure functions

L. Basano and P. Ottonello

Rev. Sci. Instrum. 56, 2070 (1985); http://dx.doi.org/10.1063/1.1138421 (4 pages) | Cited 2 times

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It has been recently shown that the structure function S(τ)=〈[I(t)−I(t+τ)]2〉 can often replace with success the correlation function C(τ)=〈I(t) I(t+τ)〉. We show that at high pulse rates a serial structure correlator is much faster than a serial time‐delay type correlator and represents, therefore, a significant improvement in the development of low‐cost instruments for photoelectron statistics. We describe a simple serial structure correlator and report some preliminary results obtained with this instrument.
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07.05.Hd Data acquisition: hardware and software
07.05.Kf Data analysis: algorithms and implementation; data management
07.05.Rm Data presentation and visualization: algorithms and implementation
07.78.+s Electron, positron, and ion microscopes; electron diffractometers

An improved optical system for photofield emission

P. J. Donders, K. W. Hadley, and M. J. G. Lee

Rev. Sci. Instrum. 56, 2074 (1985); http://dx.doi.org/10.1063/1.1138422 (3 pages) | Cited 5 times

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An improved optical system has been designed for use in experimental studies of photofield emission. By increasing the angle of convergence of the focused laser beam onto the field emitter a smaller focal spot is obtained. For a given beam intensity, this results in a substantial increase in the irradiance at the emitting surface. In addition, the smaller focal spot reduces the laser‐induced temperature rise of the field emitter for a given irradiance. The design of the improved optical system is discussed and its performance is evaluated.
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42.15.Eq Optical system design
79.70.+q Field emission, ionization, evaporation, and desorption
79.60.-i Photoemission and photoelectron spectra
85.60.-q Optoelectronic devices

Low‐energy electron diffraction system using a position‐sensitive detector

E. G. McRae, R. A. Malic, and D. A. Kapilow

Rev. Sci. Instrum. 56, 2077 (1985); http://dx.doi.org/10.1063/1.1138423 (7 pages) | Cited 33 times

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A low‐energy electron diffraction (LEED) system using a position‐sensitive detector is described. The design requirements for LEED observations are outlined. Most of these requirements are realized in a system incorporating a miniature, movable electron gun and a position‐sensitive detector of the resistive anode type, interfaced to a computer. This system has been used to make 128×128 channel digital records of LED patterns. The speed of data acquisition is limited by the detector hardware and is 20 kHz. Records of good quality (0.1° instrumental angular resolving power) can be made by counting 5×105 electrons. Illustrative applications to silicon and tungsten crystal surfaces and prospects for improving the system are described.
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61.05.jh Low-energy electron diffraction (LEED) and reflection high-energy electron diffraction (RHEED)

Temperature stage for ultralow‐temperature oxygen plasma ashing (L2TA)

Mark T. Bernius, J. Thomas Brenna, and George H. Morrison

Rev. Sci. Instrum. 56, 2084 (1985); http://dx.doi.org/10.1063/1.1138424 (4 pages)

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This paper describes an apparatus that allows the decomposition of organic materials by a radio frequency excited oxygen plasma afterglow at temperatures as low as −70 °C prior to analytical study. The usefulness of this technique is demonstrated by the freeze drying and ashing of frozen‐hydrated biological samples. Subsequent analysis indicates that the cell morphology seen in two dimensions remains intact after such treatment.
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06.60.Ei Sample preparation (including design of sample holders)
87.80.-y Biophysical techniques (research methods)
52.75.-d Plasma devices

Single‐crystal silicon high‐Q torsional oscillators

R. N. Kleiman, G. K. Kaminsky, J. D. Reppy, R. Pindak, and D. J. Bishop

Rev. Sci. Instrum. 56, 2088 (1985); http://dx.doi.org/10.1063/1.1138425 (4 pages) | Cited 78 times

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We describe techniques for constructing single‐crystal silicon high‐Q torsional oscillators. The oscillators are fabricated by the high‐precision micromachining of silicon using orientation‐dependent etches. We describe methods for using these oscillators as very powerful probes of the mechanical properties of a variety of physical systems.
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84.30.Ng Oscillators, pulse generators, and function generators
85.30.Fg Bulk semiconductor and conductivity oscillation devices (including Hall effect devices, space-charge-limited devices, and Gunn effect devices)

An instrument to synchronize Thomson scattering measurements with magnetohydrodynamic activity

A. L. Wintenberg, E. A. Lazarus, R. R. Kindsfather, and J. W. Halliwell

Rev. Sci. Instrum. 56, 2092 (1985); http://dx.doi.org/10.1063/1.1138426 (5 pages)

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We describe an instrument that synchronizes the firing of a ruby laser for a Thomson scattering diagnostic with audio‐frequency plasma oscillations. The instrument uses analog signal processing circuits to separate signal components, remove unwanted components, and produce zero‐phase synchronization pulses. A digitally controlled, self‐adjusting bandpass filter is used for sine wave processing. Additional circuitry produces pulses at the desired phase of the signal and calculates the time to start the laser‐firing sequence in advance of the desired phase. A CAMAC‐controlled data‐acquisition system is incorporated to monitor the synchronization process and to ensure that the laser is fired on the correct phase.
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52.70.Kz Optical (ultraviolet, visible, infrared) measurements
52.70.La X-ray and γ-ray measurements

Effect of gas mixing on H− production in a multicusp source

K. N. Leung, K. W. Ehlers, and R. V. Pyle

Rev. Sci. Instrum. 56, 2097 (1985); http://dx.doi.org/10.1063/1.1138427 (4 pages) | Cited 14 times

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The effect of gas mixing on volume H− production in a magnetically filtered multicusp source has been investigated. By applying the proper bias voltage on the plasma electrode, the addition of xenon or argon gases to a hydrogen discharge can enhance the H− yield. This increase in H− output is closely related to the increase in plasma electron density in the filter and extraction chamber regions.
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29.25.Lg Ion sources: polarized
29.25.Ni Ion sources: positive and negative
52.50.Dg Plasma sources

E parallel B canted detector neutral‐particle spectrometer

C. J. Armentrout, G. Bramson, and R. Evanko

Rev. Sci. Instrum. 56, 2101 (1985); http://dx.doi.org/10.1063/1.1138428 (10 pages) | Cited 10 times

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A multichannel, mass‐discriminating, neutral‐particle spectrometer using parallel E and B analyzer fields has been operational on the Doublet III tokamak. The device records 60 energy channels each of hydrogen and deuterium, simultaneously, during a shot with a dynamic range in energy of greater than 20. Its unique feature is a microchannel plate detector plane set at an angle to the exit face of the magnet. This angled detector plane linearizes the columns of each mass which simplifies the detector design, and permits the magnet gap to be very small. The narrow gap minimizes figure field effects on particle trajectories and simplifies power supply and cooling design. Details are given on the design, calibration, and instrumentation of the device, as well as on its operation and experimental results.
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52.70.Nc Particle measurements
07.75.+h Mass spectrometers
52.55.Fa Tokamaks, spherical tokamaks

Low‐inductance capacitive probe for spark gap voltage measurements

David M. Barrett, Stanley R. Byron, Edward A. Crawford, Dennis H. Ford, Wayne D. Kimura, and Mark J. Kushner

Rev. Sci. Instrum. 56, 2111 (1985); http://dx.doi.org/10.1063/1.1138429 (5 pages) | Cited 3 times

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A novel high‐voltage (>50 kV) capacitive probe has been developed to measure the voltage drop across a laser‐triggered spark gap. The capacitors which comprise the voltage probe consist of three flat, annular rings that are housed within the spark gap chamber. The rings are oriented perpendicular to the spark column axis such that the column is formed in the open center of the rings. Polyethylene and Kapton foil are employed as dielectrics. The resistive portion of the divider is housed in a shielded enclosure external to the switch chamber. The inherent simplicity of the probe design ensures low inductance while minimizing stray capacitance; thus, the probe has excellent response characteristics (≊1‐ns theoretical rise time), and does not interfere with the performance of the switch. The probe has also been designed to permit access for laser triggering and interferometric measurements of the spark column formation. The voltage, current, and resistance characteristics of a laser‐triggered spark gap for various gas mixtures are also discussed.
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07.50.-e Electrical and electronic instruments and components
52.80.Mg Arcs; sparks; lightning; atmospheric electricity
52.75.Kq Plasma switches (e.g., spark gaps)

Self‐matched high‐voltage rectangular wave pulse generator

M. Ishii and H. Yamada

Rev. Sci. Instrum. 56, 2116 (1985); http://dx.doi.org/10.1063/1.1138430 (3 pages) | Cited 8 times

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This article describes the self‐matched pulse generator, an efficient high‐voltage generator which produces a rectangular wave pulse. It generates rectangular wave pulses with a duration from a few nanoseconds to a few microseconds. The waveform of the generated pulses is maintained regardless of the resistivity of the load. The principles of its operation and applications are described.
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84.30.Ng Oscillators, pulse generators, and function generators
84.70.+p High-current and high-voltage technology: power systems; power transmission lines and cables

Improved diamond anvil high‐pressure cell for single‐crystal work

J. Koepke, W. Dieterich, J. Glinnemann, and H. Schulz

Rev. Sci. Instrum. 56, 2119 (1985); http://dx.doi.org/10.1063/1.1138380 (4 pages) | Cited 7 times

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A diamond anvil high‐pressure cell especially designed for single‐crystal x‐ray diffraction studies is described, and with its commercial STOE goniometer head the new cell fits to almost every diffractometer type in use. In this high‐pressure cell the x‐ray beam passes nearly perpendicular to the pressure generating force. This geometry also allows the cell to be used on Weissenberg cameras, but with double‐radius film cylinders and adequately enlarged layer line screens. A knee‐type lever arm system generates the thrust. In the path of the beams there are no longer larger beryllium parts, which has improved the signal‐to‐noise ratio. Approximately 90% of all possible non‐Friedel reflections for Bragg angles up to 45° can be measured in the bisecting (ϑ=ω) position, up to 95% with general diffractometer settings. An analytic absorption correction was used with beryllium gasketing to eliminate the need to know the thickness of the gasket between the two diamonds. The highest pressure reached which gave satisfactory results was 2.3 GPa. Inconel gaskets were used to collect data at pressures up to 10.2 GPa. Corrections for shadowing by the beams of the cell, absorption, and overlapping of sample reflections from other single crystals inside the cell are calculated using a special control program.
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07.35.+k High-pressure apparatus; shock tubes; diamond anvil cells
61.05.C- X-ray diffraction and scattering
07.85.-m X- and γ-ray instruments

Surface reactions of metal clusters I: The fast flow cluster reactor

M. E. Geusic, M. D. Morse, S. C. O’Brien, and R. E. Smalley

Rev. Sci. Instrum. 56, 2123 (1985); http://dx.doi.org/10.1063/1.1138381 (8 pages) | Cited 103 times

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A new fast flow device for the study of metal cluster reactions in the gas phase is described and characterized. The new device utilizes metal clusters made by laser vaporization of an appropriate metal target mounted in the throat of a supersonic nozzle which exhausts into a fast‐flow reaction tube. Reactants are injected into the flowing helium–metal cluster mixture at a point in the flow tube where shock waves have reheated the gas to roughly 320 K. Turbulence in the wake of these shock waves produces efficient mixing of the reactants. Measurement of the flow properties of this reaction tube indicate a residence time of 150–200 μs with an average density of helium buffer gas equivalent to 50–100 Torr at room temperature. Subsequent free expansion of this reaction mixture into a large vacuum chamber produces a supersonic beam with extensive cooling of the various constituents in the mixture (pyrazine was measured to be rotationally cooled to 10 K). The new cluster reaction device is, therefore, an excellent source for future studies of the jet‐cooled metal cluster reaction products themselves.
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82.65.+r Surface and interface chemistry; heterogeneous catalysis at surfaces
47.70.Fw Chemically reactive flows
68.03.Fg Evaporation and condensation of liquids
68.43.Mn Adsorption kinetics
07.35.+k High-pressure apparatus; shock tubes; diamond anvil cells
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