Measurement of Intermediate Energy Gamma-Ray Cross Sections

1971 ◽  
Vol 49 (9) ◽  
pp. 1167-1178 ◽  
Author(s):  
L. C. Henry ◽  
T. J. Kennett
Keyword(s):  
Pair Production ◽  
Production Process ◽  
Cross Section ◽  
Cross Sections ◽  
Energy Region ◽  
Gamma Ray ◽  
Intermediate Energy ◽  
Energy Gamma ◽  
Pair Production Process ◽  
Better Than

Gamma-ray cross sections for 30 well-distributed energies from 121 keV to 10.827 MeV in 9 target elements ranging from carbon to uranium have been measured with an accuracy of better than 1%. Deviations from recently quoted theoretical cross sections were observed in the energy region from 6–11 MeV, particularly for high-Z target materials. The approximately Z2 dependent deviations are certainly associated with the elastic pair-production process, the present opinion being that they arise from an overestimation of the effects of atomic–electron screening on the pair cross section in the intermediate energy region.

Triple differential cross sections for the ionization of helium by intermediate-energy electrons

1988 ◽  
Vol 66 (1) ◽  
pp. 82-85
Author(s):  
K. S. Baliyan ◽  
M. K. Srivastava
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Differential Cross ◽  
Intermediate Energy ◽  
Incident Electron Energy ◽  
Cross Section Data ◽  
Satisfactory Description ◽  
Triple Differential Cross Section ◽  
Section Data ◽  
Better Than

The recent triple differential cross-section data of Jung for the ionization of helium in the coplanar asymmetric geometry at 250 eV incident electron energy is analyzed within the framework of the second Born (B2) and modified Glauber (MG) approximations. At this energy B2 and MG results, although better than those obtained by using the first Born and Glauber approximations, do not lead to a satisfactory description of the experimental data in all the kinematic situations considered here.

The absorption of high-energy photons in matter

1958 ◽  
Vol 244 (1237) ◽  
pp. 245-258 ◽  
Keyword(s):  
Pair Production ◽  
Cross Section ◽  
Cross Sections ◽  
Born Approximation ◽  
Liquid Scintillation ◽  
Scintillation Counter ◽  
High Energy ◽  
A Value ◽  
Peak Energy ◽  
Better Than

Total absorption cross-sections of hydrogen, carbon, copper, silver, lead and uranium have been measured for photons of mean energy 94 MeV. The method was to measure the transmission through an absorber of photons from the Oxford synchrotron, using a biased liquid scintillation counter to select photons of energy near the peak energy of the machine. The experimental data for hydrogen have been used to deduce a value for the cross-section for pair production in the field of the electron of 4.7 ± 0.4 millibarn. The relative cross-sections for the heavier elements have been determined to better than ± 0.2 %, and confirm the most recent calculations of the correction to the Born approximation in the theory of pair production.

Small x Physics at the SSC and the Tevatron

1987 ◽  
Vol 02 (04) ◽  
pp. 1413-1423 ◽  
Author(s):  
FREDRICK OLNESS ◽  
WU-KI TUNG
Keyword(s):  
Pair Production ◽  
Production Process ◽  
Cross Sections ◽  
Differential Cross ◽  
Parton Distribution ◽  
Distribution Functions ◽  
Parton Distribution Functions ◽  
Small X ◽  
B Quark ◽  
Pair Production Process

We examine the integrated rates and differential cross-sections for b-quark pair production and Drell-Yan processes at the SSC and the Tevatron colliders, and we determine their sensitivity to a range of possible small x behaviors for the parton distribution functions (PDF’s). We find that both the integrated rates and the differential distributions for the Drell-Yan process are very sensitive to the unknown small x behavior of the PDF’s; whereas, only the integrated rates can distinguish various input PDF’s in the b-pair production process. Experiments at the Tevatron can provide very useful information on small x physics if these two processes, especially Drell-Yan, can be measured.

Development of the TIGRE compton telescope for intermediate-energy gamma-ray astronomy

2003 ◽  
Vol 50 (2) ◽  
pp. 251-257 ◽  
Author(s):  
T.J. O'Neill ◽  
D. Bhattacharya ◽  
M. Polsen ◽  
A.D. Zych ◽  
J. Samimi ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Intermediate Energy ◽  
Gamma Ray Astronomy ◽  
Energy Gamma ◽  
Compton Telescope

Measurement of Neutron Capture Cross Section and Gamma-Ray Spectra of 88Sr in keV Energy Region

2011 ◽  
Vol 59 (2(3)) ◽  
pp. 1844-1847 ◽  
Author(s):  
T. Katabuchi ◽  
N. C. Hai ◽  
M. Igashira ◽  
S. Kamada ◽  
M. Tajika ◽  
...  
Keyword(s):  
Cross Section ◽  
Neutron Capture ◽  
Energy Region ◽  
Capture Cross Section ◽  
Gamma Ray ◽  
Capture Cross ◽  
Neutron Capture Cross Section

scholarly journals Absolute cross section measurements of 238U(n,f) and 237Np(n,f) in the neutron energy range 1-2.4 MeV

2019 ◽  
Vol 211 ◽  
pp. 03009
Author(s):  
Paula Salvador-Castiñeira ◽  
Franz-Josef Hambsch ◽  
Alf Göök ◽  
Marzio Vidali ◽  
Nigel P. Hawkes ◽  
...  
Keyword(s):  
Cross Section ◽  
Neutron Energy ◽  
Cross Sections ◽  
Energy Region ◽  
Power Plants ◽  
National Physical Laboratory ◽  
Absolute Cross Section ◽  
Neutron Energy Range ◽  
Physical Laboratory ◽  
Low Energies

New standard (n,f) cross sections other than 235U are important to study the relevant cross sections for Generation-IV power plants. A specific need for such standards is for performing new experiments with quasimonoenergetic neutron beams, such as those produced by Van de Graaf accelerators. Neutrons down-scattered to low energies in the experimental environment, so called room-return, become relevant for this type of measurements. Hence, a standard (n,f) cross section with a fission threshold is of great interest, in order to suppress the contribution from room-return background. For this reason we have performed two experiments at the VDG of the National Physical Laboratory to measure absolutely the (n,f) cross sections of 235U, 238U and 237Np in the fast neutron energy region. Our preliminary results are in agreement with the most up-to-date evaluations.

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