ELECTRON CAPTURE CROSS SECTIONS

1954 ◽  
Vol 32 (6) ◽  
pp. 393-405 ◽  
Author(s):  
Harry Schiff
Keyword(s):  
Electron Capture ◽  
Cross Section ◽  
Cross Sections ◽  
Born Approximation ◽  
Alpha Particles ◽  
Electron Interaction ◽  
Capture Cross ◽  
The Cross ◽  
Singly Charged ◽  
Capture Cross Sections

Electron capture cross sections are calculated in the first Born approximation for alpha particles passing through hydrogen and singly charged helium ions passing through helium using the complete interaction Hamiltonian. Estimations of captures into excited states are made with the help of the partial cross sections obtained in a simple closed form using only the (incident ion)−(electron) interaction. The results indicate that the first Born approximation, using the complete interaction, is quite adequate in the velocity range given by [Formula: see text]. An impact parameter calculation for protons in hydrogen shows that the cross section obtained using only the (incident ion)–(electron) interaction gives unphysical results at low velocities [Formula: see text], and that most of the contribution to the cross section arises from impact parameters p > a0, where a0 is the radius of the first Bohr orbit in hydrogen.

Charge transfer in the presence of a radiation field

1998 ◽  
Vol 76 (3) ◽  
pp. 245-250 ◽  
Author(s):  
S -M Li ◽  
J -G Khou ◽  
Z -F Zhou ◽  
J Chen ◽  
Y -Y Liu
Keyword(s):  
Charge Transfer ◽  
Cross Section ◽  
Cross Sections ◽  
Born Approximation ◽  
Atomic Hydrogen ◽  
Capture Cross ◽  
Exchange Collision ◽  
Increasing Functions ◽  
Theoretical Results ◽  
Capture Cross Sections

In the first Born approximation, the dressing modification in laser-assisted charge exchange collision is investigated. The crosssections for electron capture by a proton from dressed atomic hydrogen and dressed helium targets are calculated within awide energy range. Theoretical results show that with impact energy increasing, the dressing effect leads to increasingly significant cross-section modifications. The modified capture cross sections are increasing functions of the ratio of laser strength to frequency. PACS Nos.: 34.50.Rk; 34.70.+e; 32.80.Wr; and 34.90.+q

Meyer-Neldel Rule in Deep-Level-Transient-Spectroscopy and its Ramifications

2003 ◽  
Vol 763 ◽  
Author(s):  
Richard S. Crandall
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Deep Level Transient Spectroscopy ◽  
Deep Level ◽  
Capture Cross ◽  
Emission Data ◽  
The Cross ◽  
Transient Spectroscopy ◽  
Capture Cross Sections

AbstractThis paper presents data showing a Meyer-Neldel rule (MNR) in InGaAsN alloys. It is shown that without this knowledge, significant errors will be made using Deep-Level Transient-Spectroscopy (DLTS) emission data to determine capture cross sections. By correctly accounting for the MNR in analyzing the DLTS data the correct value of the cross section is obtained.

Oxidation Induced ON1, ON2a/b Defects in 4H-SiC Characterized by DLTS

2014 ◽  
Vol 778-780 ◽  
pp. 281-284 ◽  
Author(s):  
Ian D. Booker ◽  
Hassan Abdalla ◽  
Louise Lilja ◽  
Jawad ul Hassan ◽  
Peder Bergman ◽  
...  
Keyword(s):  
Correlation Function ◽  
Energy Level ◽  
Electron Capture ◽  
Cross Section ◽  
Cross Sections ◽  
Capture Cross Section ◽  
Capture Cross ◽  
Electron Capture Cross Section ◽  
Pulse Measurement ◽  
Capture Cross Sections

The deep levels ON1and ON2a/bintroduced by oxidation into 4H-SiC are characterized via standard DLTS and via filling pulse dependent DLTS measurements. Separation of the closely spaced ON2a/bdefect is achieved by using a higher resolution correlation function (Gaver-Stehfest 4) and apparent energy level, apparent electron capture cross section and filling pulse measurement derived capture cross sections are given.

Single electron capture by Ar2+ in Ne, Ar, and Kr gases

1977 ◽  
Vol 55 (18) ◽  
pp. 1594-1600 ◽  
Author(s):  
H. C. Suk ◽  
A. Guilbaud ◽  
B. Hird
Keyword(s):  
Electron Capture ◽  
Cross Sections ◽  
Detection System ◽  
State Theory ◽  
Single Electron ◽  
Final States ◽  
Single Electron Capture ◽  
The Cross ◽  
Singly Charged ◽  
Capture Cross Sections

Measurements of single electron capture cross sections by Ar2+ ions in thin targets of neon, argon, and krypton have been made with an absolute accuracy of about 5%. The detection system was constructed so as to have a uniform efficiency over the range of angles and energies at which the singly charged Ar+ ions were produced in the charge exchange. Discrepancies with the extrapolated absolute values of previous measurements were found, but the energy variations of the cross section are in much better agreement. It seems possible to account for the energy variation of the cross sections with the two state theory when it is assumed that the ions of both the initial and the final states are all in their ground states.

Single electron capture cross sections of the 2P3/2 and 2P1/2 state argon and krypton ions

1968 ◽  
Vol 46 (21) ◽  
pp. 2339-2345 ◽  
Author(s):  
J. F. Williams
Keyword(s):  
Electron Capture ◽  
Cross Section ◽  
Cross Sections ◽  
Ionization Probability ◽  
Reaction Cross ◽  
Single Electron ◽  
Capture Cross ◽  
Average Electron Energy ◽  
Single Electron Capture ◽  
Capture Cross Sections

The ionization probability curves of argon and krypton atoms within 1 eV of threshold have been studied for electron impact with an average electron energy distribution of 0.035 eV (FWHM). In krypton, changes in the slope of the ionization probability curves occur at electron energies close to the spectroscopically observed autoionization levels between the 2P3/2 and 2P1/2 levels. Ions which have been formed in such a manner are then used as primary ions in charge-transfer reactions. Total single electron capture cross sections have been measured for 2P3/2 and 2P1/2 state argon and krypton ions incident upon argon and krypton atoms, respectively. Upon the presumption of the applicability of the adiabatic hypothesis, it appears, for single electron capture reactions of krypton ions upon krypton atoms over the relative energy range 500–1500 eV, that (a) the reaction 2P3/2 → 2P3/2 is dominant over the reaction 2P3/2 → 2P1/2, (b) the cross section for the 2P3/2 → 2P3/2 reaction is greater than the 2P1/2 → 2P1/2 reaction cross section, and (c) little information can be deduced for the relative values of the forward and reverse [Formula: see text] reaction cross sections.

THERMAL NEUTRON CAPTURE CROSS-SECTION OF Na23 AND Mn55

1953 ◽  
Vol 31 (3) ◽  
pp. 204-206 ◽  
Author(s):  
Rosalie M. Bartholomew ◽  
R. C. Hawkings ◽  
W. F. Merritt ◽  
L. Yaffe
Keyword(s):  
Thermal Neutron ◽  
Cross Section ◽  
Cross Sections ◽  
Neutron Capture ◽  
Half Life ◽  
Capture Cross Section ◽  
Thermal Neutron Capture ◽  
Capture Cross ◽  
Neutron Capture Cross Section ◽  
Capture Cross Sections

The thermal neutron capture cross sections of Na23 and Mn55 have been determined using the activation method. The values are 0.53 ± 0.03 and 12.7 ± 0.3 barns respectively with respect to σAul97 = 93 barns. These agree well with recent pile oscillator results. The half-life for Mn56 is found to be 2.576 ± 0.002 hr.

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