Energy loss of 18 keV electrons in gaseous T and quench condensed D films

Abstract

Measurements of the energy loss of fast electrons at an energy of 18 keV have been performed on molecules of hydrogen isotopes, gaseous T2 and frozen D2. Whereas in the case of gaseous T2 the values of total inelastic cross-section (σtot, gaseous = (3.40 ± 0.07) × 10 −18 cm 2 for E = 18.6 keV), average energy loss (εgaseous = (29.9 ± 1.0) eV) and peak position of the energy loss spectra (ε1, gaseous = 12.6 eV) agree well with the expectations, the corresponding values for quench condensed D2 differ significantly from the ones for gaseous T2. We observe a significant lower total inelastic cross-section (σ tot, solid = (2.98 ± 0.16) × 10 −18 cm 2 , for E = 18.6 keV) larger average energy loss (ε solid = (34.4 ± 3.0) eV) and higher peak position (ε 1, solid = (14.1 +0.7 −0.6 ) eV). These differences may be interpreted in terms of changes of the final state spectrum. A CI calculation for a D2 cluster shows indeed a clear shift of the excited states in agreement with the observation. PACS.34.80.Gs Molecular excitation and ionization by electron impact -78.90.+t Other topics in optical properties, condensed matter spectroscopy and other interactions of particles and radiation with condensed matter

On dewetting dynamics of solid films of hydrogen isotopes and its influence on tritium spectroscopy

“…The common steep rise at 17.825 keV occurs when the filter opens to the elastic K conversion peak. After reaching a plateau the intensity rises further when the filter opens to the first electronically excited states of D 2 at about 15 eV [17] and to the closest shake up satellites at 20 eV. Lowering the filter potential further, the intensity rises smoothly until the entire energy loss spectrum is integrated up and the filter is open for all electrons.…”

A White Paper on keV sterile neutrino Dark Matter

“…Energy losses of the β electrons due to inelastic scattering in the source are unavoidable [903]. Furthermore, the source section poses magnetic traps for electrons emitted under a large angle with respect to the beam axis.…”

“…After the capture event has occurred, the recoiling electron might scatter on one (or many) of the tritium atoms before reaching the detector where its energy is measured. The cross section for inelastic electron-tritium scattering is σ eT ∼ 10 −18 cm 2 [903] and assuming a homogenous gas of tritium in cubical volume L 3 , the mean free path is given by λ = 1/(σ eT n T ) ∼ (10 −4 cm)(L/100 cm) 3 (M T /10 kg) −1 . If λ L a large number of scatterings can occur, and their collective effect is to broaden the electron spectrum.…”

Precise energy of the 9.4 keV gamma transition observed in the 83Rb decay

“…The conversion electrons of 9.4 and 32.2 keV transitions observed in the decay of the isomeric state 83m Kr (the daughter nucleus of 83 Rb) proved to be useful in previous tritium neutrino experiments [5][6][7][8][9][10]. Currently, the conversion electrons from subshell K of the 32 keV transition, i.e.…”