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Demonstrating The Utility Of Boron Based Precursor Molecules For Selective Area Deposition In A Scanning Tunneling Microscope, F. Keith Perkins, M. Onellion, Sunwoo Lee, Peter A. Dowben May 1992

Demonstrating The Utility Of Boron Based Precursor Molecules For Selective Area Deposition In A Scanning Tunneling Microscope, F. Keith Perkins, M. Onellion, Sunwoo Lee, Peter A. Dowben

Peter Dowben Publications

The scanning tunneling microscope (STM) can be used to selectively deposit material from a gaseous precursor compound. Ultra-small (less than a 100 nm across) spatial dimensions for selective area deposition may be achieved by this means. In this paper we outline a scheme for selecting and designing main group cluster compounds and organometallics for this type of selective area deposition using nido-decaborane(l4) as an example.

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Multiplet Fine Structure Of The Gd And Tb 5p Levels, Dongqi Li, Peter A. Dowben, M. Onellion May 1992

Multiplet Fine Structure Of The Gd And Tb 5p Levels, Dongqi Li, Peter A. Dowben, M. Onellion

Peter Dowben Publications

Fine structure is observed in the photoemission of Gd and Tb 5p levels as a result of multiplet splitting. These splittings are the consequence of different J final states that occur as a result of interactions with partly filled 4f and/or 5d levels.

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Automated Seebeck Measurements Applied To Conducting Ceramics, J. S. Shapiro Apr 1992

Automated Seebeck Measurements Applied To Conducting Ceramics, J. S. Shapiro

Opportunities for Undergraduate Research Experience Program (OURE)

The Seebeck coefficient (also known as thermopower) is important in the characterization of conducting ceramics because it is very sensitive to the electronic structure. An apparatus was built during the Fall of 1990 and Spring of 1991 which was designed to measure the Seebeck coefficient in small high-resistivity samples in the temperature range from 80 K to 450 K. A reproducible thermocouple-to-sample electrical and thermal contact technique was found to be important to data accuracy but difficult to achieve. The goals of this project were to improve the thermocouple block design to give better thermal and electrical contact with the …

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Design And Development Of A Superconducting Induction Motor, Terry Bowness Apr 1992

Design And Development Of A Superconducting Induction Motor, Terry Bowness

Opportunities for Undergraduate Research Experience Program (OURE)

The discovery of high-Tc superconductors has led to the development of a number of experimental superconducting motors. This report documents the design, construction, and methods of evaluating the performance of an induction motor with a high-Tc superconducting rotor. While others have utilized the Meissner effect, our superconducting motor works due to Lenz’s law. In theory such a device will act as an induction motor only during start-up, after which its behavior is more like that of a synchronous machine. With a one-pole copper squirrel cage providing start-up torque two high-Tc discs encased in the rotor core act …

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Bulk And Surface Singularity Indices In The Alkali Metals, G. K. Wertheim, D. Mark Riffe, P. H. Citrin Apr 1992

Bulk And Surface Singularity Indices In The Alkali Metals, G. K. Wertheim, D. Mark Riffe, P. H. Citrin

All Physics Faculty Publications

Photoemission data from (110) films of Li, Na, and Rb, in which the signal from the first atomic layer is well resolved, show that the core-hole-screening singularity index is ∼40% larger at the surface than in the bulk for all three metals. This result, which is indicative of the more atomiclike character of metal surface atoms, in general, is particularly large for the alkali metals because their conduction-electron screening is mainly s-like. In addition to quantifying the difference in screening at the surface, the data provide bulk singularity indices of 0.22, 0.16, and 0.14 for Li, Na, and Rb, respectively. …

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Anomalous Dipolar Flexoelectric Effect In A Nematic Main-Chain Polymer, Rolfe G. Petschek, Eugene M. Terentjev Apr 1992

Anomalous Dipolar Flexoelectric Effect In A Nematic Main-Chain Polymer, Rolfe G. Petschek, Eugene M. Terentjev

Faculty Scholarship

An anomalously large flexoelectric effect is predicted in the nematic phase of thermotropic main-chain polymers, which have a defined orientation of subsequent monomers bonded on the chain. We identify two different ranges of order parameters. When the persistence length of the chain in the direction parallel to the order parameters is larger than a monomer length but not too long (small order parameter), the longitudinal flexoelectric coefficient f is proportional to this exponentially large persistence length, assuming that the polymers are many persistence lengths long. This result corresponds to the simple estimation that relates flexoelectric coefficients to the Frank elastic …

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Scaling Dynamics Of Aerosol Coagulation, B. J. Olivier, C. M. Sorensen, Thomas W. Taylor Apr 1992

Scaling Dynamics Of Aerosol Coagulation, B. J. Olivier, C. M. Sorensen, Thomas W. Taylor

Physics Faculty Publications

A combination of static and quasielastic light scattering and the theory of scaling solutions to Smoluchowski's equation was used to determine the absolute coagulation rate K'0 and kernel homogeneity lambda of a coagulating liquid-drop aerosol. Droplet sizes ranged from 0.23 to 0.42-mu-m, implying Knudsen numbers in the range 0.26 and 0.14. The temporal evolution of the number concentration M0 and the modal radius r(M) of an assumed zeroth-order log-normal distribution showed near-power-law behavior similar to that predicted by the scaling theory. From the temporal scaling behavior of M0(t) and r(M)(t), the absolute coagulation rate was calculated. The coagulation rates from …

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Single And Double Ionization Of Helium By Highly Charged Sulfur Ions, Karen M. Lifrieri Apr 1992

Single And Double Ionization Of Helium By Highly Charged Sulfur Ions, Karen M. Lifrieri

Masters Theses

Single and double ionization of helium by highly charged sulfur projectiles is investigated over an energy range of 0.16 to 1.6 MeV/u. Absolute cross sections for the processes of pure ionization, ionization associated with single capture, and ionization associated with single loss by S6,13+ projectiles were experimentally determined and compared with previous results and theories. Ratios of double-tosingle ionization for each outgoing projectile charge state were also determined and compared with theory. The pure ionization ratios for S6+ at the highest energies investigated show the q2/E dependence predicted by Knudsen et al. (1984). For S13+ …

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Electron Production In Proton Collisions With Atoms And Molecules: Energy Distributions, M. Eugene Rudd, Yongki Kim, Don H. Madison, Timothy Gay Apr 1992

Electron Production In Proton Collisions With Atoms And Molecules: Energy Distributions, M. Eugene Rudd, Yongki Kim, Don H. Madison, Timothy Gay

Physics Faculty Research & Creative Works

All known data on the energy distribution of secondary electrons from collisions of protons with atoms and molecules have been reviewed and differential cross sections have been collected. The two experimental methods used to obtain the data are discussed and possible sources of error pointed out. Theoretical treatments are reviewed and several methods of checking the consistency of the data are discussed. Two semiempirical models have been chosen to represent the differential cross sections, and parameters for these models are given which fit the average of the experimental data, subject to known constraints. Recommended values of differential cross sections are …

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Electron Production In Proton Collisions With Atoms And Molecules: Energy Distributions, M. Eugene Rudd, Y.-K. Kim, D. H. Madison, Timothy J. Gay Apr 1992

Electron Production In Proton Collisions With Atoms And Molecules: Energy Distributions, M. Eugene Rudd, Y.-K. Kim, D. H. Madison, Timothy J. Gay

Timothy J. Gay Publications

All known data on the energy distribution of secondary electrons from collisions of protons with atoms and molecules have been reviewed and differential cross sections have been collected. The two experimental methods used to obtain the data are discussed and possible sources of error pointed out. Theoretical treatments are reviewed and several methods of checking the consistency of the data are discussed. Two semiempirical models have been chosen to represent the differential cross sections, and parameters for these models are given which fit the average of the experimental data, subject to known constraints. Recommended values of differential cross sections are …

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Angular Distributions For Near-Threshold (E,2E) Processes For H, He, And Other Rare-Gas Targets, Cheng Pan, Anthony F. Starace Apr 1992

Angular Distributions For Near-Threshold (E,2E) Processes For H, He, And Other Rare-Gas Targets, Cheng Pan, Anthony F. Starace

Anthony F. Starace Publications

Distorted-wave calculations of the triply differential cross sections for electron-impact ionization of H, He, Ne, Ar, Kr, and Xe are presented for final-state electrons sharing ≤4 eV excess energy and for the coplanar, θ12=π geometry. Results for H and He targets, presented briefly elsewhere [C. Pan and A. F. Starace, Phys. Rev. Lett. 67, 185 (1991)], are analyzed in greater detail and compared with available experimental and other theoretical results. In particular, for He targets the effects of exchange and of second-order capture processes are exhibited. These are shown to be of lesser importance than other short-range effects …

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Temperature-Dependent Electronic Structure In A Localized-Magnetic-Moment System: Gadolinium, Dongqi Li, Jiandi Zhang, Peter A. Dowben, M. Onellion Apr 1992

Temperature-Dependent Electronic Structure In A Localized-Magnetic-Moment System: Gadolinium, Dongqi Li, Jiandi Zhang, Peter A. Dowben, M. Onellion

Peter Dowben Publications

At normal emission, the bulklike band in gadolinium overlayers on W(110) shifts toward EF from 1.64 eV at 310 K to 1.43 eV at 230 K in photoemission. This is accompanied by an increase of the feature width from 0.8 eV at 320 K to 1.1 eV at 230 K. The surface-state binding energy remains unchanged, though the width increases significantly with increasing temperature. The different effects of temperature upon the photoemission results obtained for the bulklike and surface states are interpreted as magnetic-order-induced band movement and spin mixing, respectively, and are discussed in the light of a quasiparticle theory. …

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Search For The Mössbauer Effect In 109ag, Shokrollah Rezaie-Serej Apr 1992

Search For The Mössbauer Effect In 109ag, Shokrollah Rezaie-Serej

Physics Theses & Dissertations

The 88-keV first-excited nuclear state in 109Ag has a mean lifetime of 57.1 sec and a corresponding natural linewidth of 1.15 x 10-17 eV which is nearly six orders of magnitude narrower than the width for the 93-keV 13.2-μsec state in 67Zn. The 93-keV transition in 67Zn has the narrowest linewidth for which the Mossbauer effect has been observed. The 88-keV transition in 109Ag is obviously a very difficult case for the observation of the Mossbauer effect and provides a stringent test for exploring the practical limits of inhomogeneous line broadening in real single …

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Hyperspherical Coordinate Description Of Single- And Multiphoton Processes In Two-Electron Systems, Anthony F. Starace Mar 1992

Hyperspherical Coordinate Description Of Single- And Multiphoton Processes In Two-Electron Systems, Anthony F. Starace

Anthony F. Starace Publications

The purpose of this chapter is to review the use of the adiabatic hyperspherical approximation for the quantitative calculation of single- and multiphoton cross sections of two-electron systems. In Section 2 we provide a brief general orientation to the hyperspherical coordinate representation, the adiabatic approximation, and a diabatic approximation for treating strongly avoided crossings between adiabatic potential curves. In Section 3 we review applications to photoionization and photodetachment processes in He, Be, H–, and Ps–. In Section 4 we review applications to multiphoton processes in H–. Finally, in Section 5 we assess the adiabatic …

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Thermal And Surface Core-Electron Binding-Energy Shifts In Metals, D. Mark Riffe, G. K. Wertheim, D. N. E. Buchanan, P. H. Citrin Mar 1992

Thermal And Surface Core-Electron Binding-Energy Shifts In Metals, D. Mark Riffe, G. K. Wertheim, D. N. E. Buchanan, P. H. Citrin

All Physics Faculty Publications

High-resolution photoemission spectra from the shallow core levels of alkali metals and of In have been obtained between 78 K and room temperature. The data yield values for the alkali-metal surface-atom core-level shift and show thermal shifts of comparable size for bulk and surface. The positive surface shifts are due to the spill-out of conduction-electron charge, which is responsible for the surface dipole layer. The surface shifts are in good agreement with values obtained from a Born-Haber cycle expressed in terms of surface energies. The thermal shifts are proportional to the lattice expansion, and arise from both initial-state and final-state …

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Electric-Field-Modulated Reflectivity At A Liquid-Crystal Substrate Interface, Sanjay Tripathi, Rolfe G. Petschek, Charles Rosenblatt Mar 1992

Electric-Field-Modulated Reflectivity At A Liquid-Crystal Substrate Interface, Sanjay Tripathi, Rolfe G. Petschek, Charles Rosenblatt

Faculty Scholarship

Measurements of reflectivity versus ac electric field E were performed in the nematic phase of octylcyanobiphenyl homeotropically aligned between two indium tin oxide coated glass slides. The change in reflectivity R was found to be linear in E, with d(R)/dE increasing monotonically toward the nematic-isotropic transition temperature. In addition, the phase of R at the front and back surfaces differed by. Such an effect will arise from t/Iorder electricity, whereby a term proportional to the product of the electric field and the gradient of the nematic order parameter appears in the bulk free energy. This term integrates to yield a …

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Pressure Dependence Of The Thermal Conductivity Of Pyrophyllite To 40 Kbar, Wei Chen, Daniel L. Decker Mar 1992

Pressure Dependence Of The Thermal Conductivity Of Pyrophyllite To 40 Kbar, Wei Chen, Daniel L. Decker

Faculty Publications

A mathematical model for calculating the temperature distribution as a function of power delivered to a line source and the thermal conductivity of the surrounding medium in the pressure cell of a cubic-anvil press was derived. The model will handle anisotropic thermal conductivities. A simple sample assembly consisting of a line source and two or three thermocouple junctions is described. A comparison of measured to calculated temperatures yields the thermal conductivity. Thermal conductivity measurements were made on natural pyrophyllite and baked pyrophyllite to 40 kbar. For the natural pyrophyllite the thermal conductivity parallel to the bedding plane at room temperature …

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Backward Peak In The Electron Spectrum From Collisions Of 70-Kev Protons With A Target From A Hydrogen-Atom Source, M. Eugene Rudd, M. W. Gealy, G. W. Kerby, Iii, Ying-Yuan Hsu Mar 1992

Backward Peak In The Electron Spectrum From Collisions Of 70-Kev Protons With A Target From A Hydrogen-Atom Source, M. Eugene Rudd, M. W. Gealy, G. W. Kerby, Iii, Ying-Yuan Hsu

M. Eugene Rudd Publications

A large, broad peak has been found in the electron energy spectrum from 30 to 100-keV H+ + H collisions. The peak, which is centered at 31 eV, appears only in the backward directions. It is suggested that while the peak is unlikely to come from collisions with atoms in the ground or metastable states, it could arise from collisions with atoms in highly excited states or from autoionizing states of the residual H2 in the target.

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Intervalley Scattering In Gaas And Inp Probed By Pulsed Far‐Infrared Transmission Spectroscopy, Peter N. Saeta, John F. Federici, Benjamin I. Greene, Douglas R. Dykaar Mar 1992

Intervalley Scattering In Gaas And Inp Probed By Pulsed Far‐Infrared Transmission Spectroscopy, Peter N. Saeta, John F. Federici, Benjamin I. Greene, Douglas R. Dykaar

All HMC Faculty Publications and Research

The dynamics of photoexcited electrons in GaAs and InP were studied using the transmission of 200‐fs pulses of far‐infrared radiation in the spectral range 15–100 cm−1. Kinetic traces of the infrared transmission as a function of delay between optical excitation and infrared probe show a probe‐limited decrease in transmission followed by a more gradual (0.7–2 ps) drop to a steady value, consistent with the slow return of electrons from high‐mass satellite valleys. Infrared transmission spectra, analyzed in the context of a Drude model, reveal density‐dependent electron mobilities 3–4 times below equilibrium n‐doped values. Electron‐hole collisions likely account …

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A Theoretical Investigation Of The Ground And Low‐Lying Excited States Of Butadiene Radical Cation, Robert J. Cave, Michael G. Perrott '90 Mar 1992

A Theoretical Investigation Of The Ground And Low‐Lying Excited States Of Butadiene Radical Cation, Robert J. Cave, Michael G. Perrott '90

All HMC Faculty Publications and Research

Results are presented from ab initio calculations on the ground and several low‐lying excited states of the butadiene radical cation. In particular, we have calculated geometries for the ground and several excited states at the multiconfiguration self‐consistent field level and characterized the planar stationary points. The vertical ionization potentials from the neutral molecule ground state and vertical excitation energies at the computed equilibrium geometry of the cation were also examined. A variety of methods were tested for the calculation of ionization potentials and excitation energies, including multiconfiguration self‐consistent field, multireference singles and doubles configuration interaction (with and without size‐consistency correction), …

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Detection, Location, And Quantification Of Structural Damage By Neural-Netprocessed Moire Profilometry, Barry G. Grossman, Frank S. Gonzalez, Joel H. Blatt, Jeffery A. Hooker Mar 1992

Detection, Location, And Quantification Of Structural Damage By Neural-Netprocessed Moire Profilometry, Barry G. Grossman, Frank S. Gonzalez, Joel H. Blatt, Jeffery A. Hooker

Electrical Engineering and Computer Science Faculty Publications

The development of efficient high speed techniques to recognize, locate, and quantify damage is vitally important for successful automated inspection systems such as ones used for the inspection of undersea pipelines. Two critical problems must be solved to achieve these goals: the reduction of nonuseful information present in the video image and automatic recognition and quantification of extent and location of damage. Artificial neural network processed moire profilometry appears to be a promising technique to accomplish this. Real time video moire techniques have been developed which clearly distinguish damaged and undamaged areas on structures, thus reducing the amount of extraneous …

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Numerical Analysis Of Plasma Transport In Tandem Volume Magnetic Multicusp Ion Sources, Todd R. Vitko Mar 1992

Numerical Analysis Of Plasma Transport In Tandem Volume Magnetic Multicusp Ion Sources, Todd R. Vitko

Theses and Dissertations

A one-dimensional fluid model of plasma transport in tandem volume magnetic multicusp ion sources is explored. The model, the positive ion source code pos, by Glasser and Smith, calculates plasma density, drift velocity, electron temperature, and ion temperature in an ion source. The usefulness of the model is limited: (1) The plasma density trend runs opposite to experimental results, and electron temperatures are an order of magnitude higher than experimentally observed. (2) simplification of the reaction chemistry leads to a plasma balance between ionization and outflow instead of the correct balance between ionization and recombination. (3) Wall losses are …

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Shock Tube Simulation By The Smooth Particle Hydrodynamic (Sph) Method, Luke A. Lorang Mar 1992

Shock Tube Simulation By The Smooth Particle Hydrodynamic (Sph) Method, Luke A. Lorang

Theses and Dissertations

A smooth particle hydrodynamic code (SPHC) is evaluated for performing shock wave simulations by application to 1-D shock tube problems. Results of a shock tube test case with a compression ratio of 10 are compared against a Riemann shock tube problem and theoretical predictions of shock tube behavior to validate the SPH code. A Lagrangian hydrodynamic code is validated in a similar fashion. The resolution capabilities of both codes are compared using 100, 200 and 500 particles for SPHC and 100, 400 and 800 cells for the Lagrangian code. The SPH code exhibits a sharp spike in density at the …

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Design And Construction Of A Channel Electron Multiplier Based Mossbauer Spectroscopy System, Daniel J. Robbins Mar 1992

Design And Construction Of A Channel Electron Multiplier Based Mossbauer Spectroscopy System, Daniel J. Robbins

Theses and Dissertations

A channel electron multiplier (cem) detector system was designed and built to provide a signal to a Mossbauer spectroscopy system in an effort to obtain a better signal-to-noise ratio than achievable with a proportional counter system. Three cems are contained in a vacuum chamber built using standard components. Gamma, rays of 14.4-keV energy from a 57Co source enter from outside the chamber through a window and are absorbed by an 57Fe target near the cems. The target emits internal conversion electrons which are collected by the cems and a Mossbauer spectrometer collects the signal. The system produces a …

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Magnetic Relaxation And Irreversibility In A Superconducting Tl2Ba2Ca2Cu3O10±X Thin Film, V.K. Chan, Sy_Hwang Liou Mar 1992

Magnetic Relaxation And Irreversibility In A Superconducting Tl2Ba2Ca2Cu3O10±X Thin Film, V.K. Chan, Sy_Hwang Liou

Sy-Hwang Liou Publications

The magnetic relaxation in a Tl2Ba2Ca2Cu3O10±x superconducting thin film has been measured at a range of temperatures (5–70 K) and field strengths (500–5000 Oe). Measurements reveal that the relaxation obeys a logarithmic time dependence in the time interval 2000 s<t<12 000 s. The relaxation rate is both temperature and field dependent. The average pinning potential U* calculated from the relationship U*=kT/[(-1/Mi)dM/d lnt] is in the range 20–70 meV, which is similar to those of Y-Ba-Cu-O and (Bi,Pb)-Sr-Ca-Cu-O. The anomalous increase of U* at higher temperature is found to be closely related to …

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Temporary Negative Ions And Vibrational Excitation In Ch3Cl And Cd3Cl, X. Shi, T.M. Stephen, Paul Burrow Mar 1992

Temporary Negative Ions And Vibrational Excitation In Ch3Cl And Cd3Cl, X. Shi, T.M. Stephen, Paul Burrow

Paul Burrow Publications

Electron energy loss spectroscopy is used to study the vibrational modes of CH3Cl and CD3Cl excited through the formation of a temporary negative ion state centered at 3.5 eV. Using symmetry and charge distribution arguments together with the experimentally determined excitation functions for several vibrational modes, we confirm that this resonance results from filling of the 8a1 (C–Cl) σ* molecular orbital. Evidence for a broad higher-lying resonance which we attribute to the unfilled 4e orbital is also presented.

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Coverage Dependence Of K Adsorption On Si(100)—2× 1 By Core-Level Photoemission, D. Mark Riffe, G. K. Wertheim, P. H. Citrin, J. E. Rowe Feb 1992

Coverage Dependence Of K Adsorption On Si(100)—2× 1 By Core-Level Photoemission, D. Mark Riffe, G. K. Wertheim, P. H. Citrin, J. E. Rowe

All Physics Faculty Publications

Using core-level photoemission, a coverage-dependent transition in the adsorption of K on Si(100)2×1 is observed. Below ∼0.25 monolayers, a single adsorption is occupied, the asymmetry of the Si-dimer reconstruction is enhanced, and no more than ∼0.05e is transferred from K to Si. Above this coverage, multiple sites are occupied, the dimer configuration becomes more symmetric, and the K overlayer becomes increasingly metallic. These findings resolve a number of conflicting studies of this system.

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Three-Dimensional Structure Of The Ordered Phases Of Hg On Cu(001), Wei Li, Jingsu Lin, M. Karimi, Peter A. Dowben, G. Vidali Feb 1992

Three-Dimensional Structure Of The Ordered Phases Of Hg On Cu(001), Wei Li, Jingsu Lin, M. Karimi, Peter A. Dowben, G. Vidali

Peter Dowben Publications

The structures of ordered phases following adsorption of mercury on Cu(001) have been identified using helium-beam scattering and low-energy electron diffraction. We found that three of the four observed ordered submonolayer phases are high-order commensurate phases. The three-dimensional structure of these phases brought about by a periodic variation of the height of the Hg atoms above the Cu(001) plane has been measured. Furthermore, from a combined analysis of helium-beam scattering and angle-resolved photoemission data for a low-density Hg ordered overlayer, we deduce and quantify the departure from the atomic electron distribution of Hg due to adsorption. A model to analyze …

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Mott Electron Polarimetry, Timothy J. Gay, F. B. Dunning Feb 1992

Mott Electron Polarimetry, Timothy J. Gay, F. B. Dunning

Timothy J. Gay Publications

Electron polarimeters based on Mott scattering are extensively used in atomic and molecular, solid state, nuclear, and high-energy physics. This use stems from the increasing realization that much additional information concerning many physical processes can be obtained through spin-dependent measurements. In this review we discuss the basic physics and application of Mott polarimetry. A number of different Mott polarimeter designs are described that illustrate the wide range of operating energies (10 eV-1 MeV) and geometries that can be used in such instruments. The calibration of Mott polarimeters is discussed together with the potential sources of systematic error that can arise …

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Angular-Differential Cross Sections For H(2P) Formation In Intermediate-Energy Proton-Helium Collisions, D. G. Seely, S. W. Bross, A. D. Gaus, J. W. Edwards, D. R. Schultz, Timothy J. Gay, J. T. Park, J. L. Peacher Feb 1992

Angular-Differential Cross Sections For H(2P) Formation In Intermediate-Energy Proton-Helium Collisions, D. G. Seely, S. W. Bross, A. D. Gaus, J. W. Edwards, D. R. Schultz, Timothy J. Gay, J. T. Park, J. L. Peacher

Timothy J. Gay Publications

Angular-differential cross sections for charge transfer with simultaneous emission of a photon in collisions of protons with helium atoms have been measured. The incident proton energies were 25, 50, and 100 keV and the center-of-mass scattering angles were between 0 and 2.0 mrad. In the experiment, hydrogen atoms that scattered through an angle θ were detected in coincidence with photons emitted perpendicular to the scattering plane with a wavelength between 1140 and 1400 Å. Differential cross sections for capture into the 2p state of the hydrogen atom were determined from the variation in the coincidence signal with θ. The …

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