Photoionization of magnesium

1987 ◽  
Vol 65 (7) ◽  
pp. 772-776 ◽  
Author(s):  
Charlotte Froese Fischer ◽  
Hari P. Saha

Photoionization from the 3s subshell of magnesium is investigated in the energy region near threshold where several resonances have been observed. Theoretical cross sections are reported. The latter have been computed using the multi-configuration Hartree–Fock approximation extended to include a continuum function. Results are compared with other theories and experiment.

2020 ◽  
Vol 29 (08) ◽  
pp. 2050056
Author(s):  
E. M. Darwish ◽  
H. M. Al-Ghamdi

Incoherent [Formula: see text]-photoproduction on the deuteron is investigated for photon energies near threshold with particular focus on beam-target double spin asymmetries. The analysis is based on a [Formula: see text] reaction model in which realistic elementary amplitudes for [Formula: see text], [Formula: see text] and [Formula: see text] are incorporated. Numerical results on all possible beam-target double spin asymmetries of the differential and total cross-sections in the photon energy region near threshold are presented. Effects of [Formula: see text] and [Formula: see text] final-state interactions are investigated and their roles are found to be important.


2006 ◽  
Vol 39 (6) ◽  
pp. 1547-1561 ◽  
Author(s):  
M Stepanović ◽  
M Minić ◽  
D Cvejanović ◽  
J Jureta ◽  
J Kurepa ◽  
...  

The quantal theory of the continuous photo-electric absorption of radiation is briefly summarized, pàrticular attention being given to the alternative formulae available and to the accuracy to be expected in practical calculations. Detailed calculations are described for the photo-ionization cross-section of neon, a system for which it is understood that experimental data should be available in the near future. The calculation is made using Hartree-Fock wave functions and the two formulae of the dipole length and the dipole velocity. The corresponding cross-sections are found to be 5.8 and 4.4 x 10- 18 cm 2 . at the spectral head and to rise slowly with increasing frequency until a broad maximum is reached for an energy of the ejected electron of about 11 eV. A comparison is made with previous calculations on the elements from boron to neon ; the general trend of the results is discussed and improved estimates for boron and fluorine are given (10 x 10 -18 cm 2 . for boron and 4.3 x 10- 18 cm 2 . for fluorine at the spectral head).


2020 ◽  
Vol 239 ◽  
pp. 01001
Author(s):  
Guohui Zhang ◽  
Huaiyong Bai ◽  
Haoyu Jiang ◽  
Zengqi Cui ◽  
Yi Lu ◽  
...  

In the past two decades cooperating with Frank Laboratory of Neutron Physics (FLNP), Joint Institute for Nuclear Research (JINR) measurements of (n, α) reaction cross sections for 6Li, 10B, 25Mg, 39K, 40Ca, 54,56,57 Fe, 58Ni, 63Cu, 64,67 Zn, 95Mo, 143Nd and 147,149 Sm nuclei were performed in the MeV neutron energy region based on the 4.5 MV Van de Graaff accelerator at Peking University. In recent years, our measurements were extended in three aspects. Firstly, measurements were expanded from two-body reactions to three-body reactions such as 10B (n, t2 α). Secondly, the neutron energy region was extended from below 8 MeV to 8 - 11 MeV by using the HI-13 tandem accelerator of China Institute of Atomic Energy (CIAE), with which cross sections of 54,56 Fe(n, α)53,51Cr reactions were measured. Thirdly, based on the newly-built China Spallation Neutron Source (CSNS) Back-n WNS (White Neutron Source), differential and angle-integrated cross sections for 6Li(n, t) and 10B(n, α) reactions were measured in the neutron energy region from 1 eV to 3 MeV.


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