Inner-shell photoionization of ground-state lithium: Theoretical calculation in the photon energy region of hollow atomic states

Abstract We study a new dark sector signature for an atomic process of “rearrangement” in the galaxy. In this process, a hydrogen-like atomic dark matter state together with its anti-particle can rearrange to form a highly-excited bound state. This bound state will then de-excite into the ground state emitting a large number of dark photons that can be measured in experiments on Earth through their kinetic mixing with the photon. We find that for DM masses in the GeV range, the dark photons have enough energy to pass the thresholds of neutrino observatories such as Borexino and Super-Kamiokande that can probe for our scenario even when our atomic states constitute a small fraction of the total DM abundance. We study the corresponding bounds on the parameters of our model from current data as well as the prospects for future detectors.

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Energy Correlations of α-Particles in the 8Be-Nucleus Ground-State Formation Channel of the 12C(γ,3α) and 16O(γ,4α) Reactions

Ukrainian Journal of Physics ◽

10.15407/ujpe64.9.787 ◽

2019 ◽

Vol 64 (9) ◽

pp. 787

Author(s):

S. N. Afanasyev

Keyword(s):

Magnetic Field ◽

Photon Energy ◽

Relative Motion ◽

Cross Sections ◽

Ground State ◽

Diffusion Chamber ◽

Mechanism Of Interaction ◽

The Magnetic Field ◽

Maximum Photon ◽

Α Particles

The method of diffusion chamber in the magnetic field making use of a bremsstrahlung beam with a maximum photon energy of 150 MeV is applied to study the 12C(y,3a) and 16O(y,4a) reactions. A resonance identified as the ground state of 8Be nucleus is found in the distribution of events over the energy of the relative motion of two a-particles. The partial cross-sections of the 8Be nucleus formation channels are measured. It is shown that the mechanism of interaction between a y-quantum and a virtual a-particle pair takes place in this case.

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Thick target total bremsstrahlung spectra of lead compounds in the photon energy region 1–10 keV by 90Sr beta particles

Applied Radiation and Isotopes ◽

10.1016/j.apradiso.2017.09.010 ◽

2017 ◽

Vol 130 ◽

pp. 1-6

Author(s):

Suhansar Jit Sharma ◽

Tajinder Singh ◽

Doordarshi Singh ◽

Amrit Singh ◽

A.S. Dhaliwal

Keyword(s):

Photon Energy ◽

Energy Region ◽

Thick Target ◽

Beta Particles ◽

Lead Compounds

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Theoretical Calculation of Hyperfine Structures and g-factors of Ground State of Mercuric Fluoride Molecule

Acta Optica Sinica ◽

10.3788/aos201737.0902001 ◽

2017 ◽

Vol 37 (9) ◽

pp. 0902001

Author(s):

郝美 Hao Mei ◽

汪海玲 Wang Hailing ◽

印建平 Yin Jianping

Keyword(s):

Theoretical Calculation ◽

Ground State ◽

Hyperfine Structures ◽

G Factors

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The Kr valence photoelectron satellite lines in the photon energy region below the 3d threshold

Journal of Physics B Atomic Molecular and Optical Physics ◽

10.1088/0953-4075/39/20/015 ◽

2006 ◽

Vol 39 (20) ◽

pp. 4169-4177 ◽

Cited By ~ 10

Author(s):

A Caló ◽

S Atanassova ◽

R Sankari ◽

A Kivimäki ◽

H Aksela ◽

...

Keyword(s):

Photon Energy ◽

Energy Region

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Photoacoustic Study of The Effect of 0.9 eV Light Illumination in Semi-Insulating GaAs

MRS Proceedings ◽

10.1557/proc-484-601 ◽

1997 ◽

Vol 484 ◽

Author(s):

Atsuhiko Fukuyama ◽

Yoshito Akashi ◽

Kenji Yoshino ◽

Kouji Maeda ◽

Tetsuo Ikari

Keyword(s):

Optical Absorption ◽

Photon Energy ◽

Metastable State ◽

Energy Region ◽

Broad Peak ◽

Light Illumination ◽

Transformation Rates ◽

The Difference ◽

First Time ◽

Absorption Measurements

AbstractThe effect of the secondary light illumination of hv = 0.9 eV on the photoquenched and the enhanced states in semi-insulating GaAs are investigated by using piezoelectric photoacoustic (PPA) measurements at 80 K. It is found that the secondary light causes an optical recovery from EL2* to EL2° and this is in agrezment with the result reported by using infrared optical absorption measurements. We observed a broad peak around 0.9 eV after the secondary light illumination for the first time. The most important finding is that the PPA spectra after the secondary light illumination on the quenched and the enhanced states are the same in the whole photon energy region. We concluded that the secondary light of hv = 0.9 eV induces both an optical recovery and generation of metastable state of the EL6 level. The difference of the transformation rates of these two processes explains well the observed complex natures of the PPA signal under the secondary light illumination.

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