Simulations of the energy loss of ions at the stopping-power maximum in a laser-induced plasma

In Physics, Chemistry, Materials Science, Biology and Medicine, it is very important to have accurate information about the stopping power of various media for electrons, that is the average energy loss per unit pathlength due to inelastic Coulomb collisions with atomic electrons of the specimen along their trajectories. Techniques such as photoemission spectroscopy, Auger electron spectroscopy, and electron energy loss spectroscopy have been used in the measurements of electron-solid interaction. In this paper we present a comprehensive technique which combines experimental and theoretical work to determine the electron stopping power for various materials by electron energy loss spectroscopy (EELS ). As an example, we measured stopping power for Si, C, and their compound SiC. The method, results and discussion are described briefly as below.The stopping power calculation is based on the modified Bethe formula at low energy:where Neff and Ieff are the effective values of the mean ionization potential, and the number of electrons participating in the process respectively. Neff and Ieff can be obtained from the sum rule relations as we discussed before3 using the energy loss function Im(−1/ε).

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Density-dependent Energy Loss of Protons in Pb and Be Targets and Percent Mass-Stopping Power from Bethe-Bloch Formula and Bichsel-Sternheimer Data Within 1–12 MeV Energy Range: A Comparative Study Based on Bland-Altman Analysis

Journal of Medical Imaging and Radiation Sciences ◽

10.1016/j.jmir.2018.10.003 ◽

2019 ◽

Vol 50 (1) ◽

pp. 149-156 ◽

Cited By ~ 6

Author(s):

Azmat Iqbal ◽

Nasir Ullah ◽

Amin Ur Rahman

Keyword(s):

Energy Loss ◽

Comparative Study ◽

Energy Range ◽

Stopping Power ◽

Altman Analysis ◽

Bland Altman Analysis ◽

Density Dependent

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Strain/Damage in Crystalline Materials Bombarded by MeV Ions: Recrystallization of GaAs by High-Dose Irradiation

MRS Proceedings ◽

10.1557/proc-35-305 ◽

1984 ◽

Vol 35 ◽

Cited By ~ 11

Author(s):

C. R. Wie ◽

T. Vreeland ◽

T. A. Tombrello

Keyword(s):

Surface Layer ◽

Energy Loss ◽

Ion Irradiation ◽

Stopping Power ◽

High Dose ◽

Double Crystal ◽

Saturation Phenomenon ◽

Nuclear Stopping ◽

X Ray ◽

Dose Irradiation

ABSTRACTMeV ion irradiation effects on semiconductor crystals, GaAs(100) and Si (111) and on an insulating crystal CaF2 (111) have been studied by the x-ray rocking curve technique using a double crystal x-ray diffractometer. The results on GaAs are particularly interesting. The strain developed by ion irradiation in the surface layers of GaAs (100) saturates to a certain level after a high dose irradiation (typically 1015/cm2), resulting in a uniform lattice spacing about 0.4% larger than the original spacing of the lattice planes parallel to the surface. The layer of uniform strain corresponds in depth to the region where electronic energy loss is dominant over nuclear collision energy loss. The saturated strain level is the same for both p-type and n-type GaAs. In the early stages of irradiation, the strain induced in the surface is shown to be proportional to the nuclear stopping power at the surface and is independent of electronic stopping power. The strain saturation phenomenon in GaAs is discussed in terms of point defect saturation in the surface layer.An isochronal (15 min.) annealing was done on the Cr-doped GaAs at temperatures between 200° C and 700° C. The intensity in the diffraction peak from the surface strained layer jumps at 200° C < T ≤ 300° C. The strain decreases gradually with temperature, approaching zero at T ≤ 500° C.The strain saturation phenomenon does not occur in the irradiated Si. The strain induced in Si is generally very low (less than 0.06%) and is interpreted to be mostly in the layers adjacent to the maximum nuclear stopping region, with zero strain in the surface layer. The data on CaF2 have been analysed with a kinematical x-ray diffraction theory to get quantitative strain and damage depth profiles for several different doses.

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NEUTRINO ENERGY LOSS AT MATTER-RADIATION DECOUPLING PHASE

Modern Physics Letters A ◽

10.1142/s0217732309000577 ◽

2009 ◽

Vol 24 (11n13) ◽

pp. 1051-1054

Author(s):

UNGKU FERWANI SALWA UNGKU IBRAHIM ◽

NOR SOFIAH AHMAD ◽

NORHASLIZA YUSOF ◽

HASAN ABU KASSIM

Keyword(s):

Energy Loss ◽

Neutrino Energy ◽

Electron Neutrino ◽

Stopping Power ◽

Power Equation ◽

Electron Positron ◽

Extra Energy ◽

Expansion Of The Universe ◽

Current Interaction ◽

The Universe

Neutrinos are produced copiously in the early universe. Neutrinos and antineutrinos ceased to be in equilibrium with radiation when the weak interaction rate becomes slower than the rate expansion of the universe. The ratio of the temperature of the photon to the temperature of the neutrino at this stage is Tγ/Tν = (11/4)1/3. We investigate the neutrino energy loss due to the oscillation of the electron neutrino into a different flavor in the charged-current interaction of νe-e- based on the work of Sulaksono and Simanjuntak. The energy loss from the neutrinos ΔEν during the decoupling of the neutrinos with the rest of the matter would be a gain in the energy of the electrons and can be obtained from the integration of stopping power equation ΔEν = (dEν/dT-1)dT-1 where Eν and T are the energy of the neutrinos and the temperature respectively. When the universe expands and matter-radiation decouples, an extra energy will be transferred to the photons via the annihilation of the electron-positron pairs, e++e-→γ+γ. This consequently will increase the temperature of the photons. The net effect to the lowest order is an increase in the ratio of the photon temperature to the neutrino temperature. The magnitude of energy loss of the neutrino is ∼10-4-10-5 MeV for the probability of conversion of νe → νi (i = μ,τ) between 0 to 1.0.

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