Resonance excitation of the
83
Kr first nuclear level (
E
= 9.4 keV) by solar axions formed via the Primakoff mechanism is sought. The γ- and X-ray photons and the conversion and Auger electrons ...arising from the excited-level relaxation are detected with a gas proportional counter of a low-background detector in the underground Baksan Neutrino Observatory. The following experimental constraint is obtained for the product of the axion–photon coupling constant and the axion mass:|
g
A
γ
×
m
A
| ≤ 6.3 × 10
-17
In the framework of the hadronic-axion model, this corresponds to a new axion-mass constraint of
m
A
≤ 12.7 eV at 95% C.L.
The resonant excitation of the
83
Kr first excited nuclear level (
E
= 9.4 keV) by solar axions whose fluxes depend on the axion–electron coupling constant
g
Ae
is sought. The γ- and X-ray photons ...and the conversion and Auger electrons from the excited-level relaxation are detected with a gas proportional counter of a low-background detector in the underground Baksan Neutrino Observatory (Institute for Nuclear Research, Russian Academy of Sciences). As a result, a new constraint
≤ 1.50 × 10
–17
(90% C.L.) has been obtained for the axion–electron and axion–nucleon coupling constants, which corresponds to new constraints on the axion mass
m
A
≤ 320 eV and
m
A
≤ 4.6 eV in the KSVZ and DFSZ axion models, respectively.
The study of low-yield effects requires not only good quality of the original data but also puts high requirements for their processing procedures to increase the efficiency of the selection of ...useful events. The exploiting of the large cylindrical proportional counter's electrostatic topology allows improving the extrapolation of information about the primary ionization of a multipoint event. Long-term calibration measurements with an external 109Cd-source allowed the development of a new method for analyzing the pulse shape from a sizeable proportional counter. Optimized analysis of the current's pulse shape from the electron cloud of primary ionization in the counter improved the resolution and energy calibration. As a result, the efficiency of selecting useful events was increased by 25%.
The energy resolution is calculated for a neodymium-containing liquid organic scintillation detector (Nd-OS) with a volume of several liters to search for neutrinoless double beta decay of
150
Nd as ...a function of the neodymium concentration up to 5 g/L. The results are presented in detailed tables and graphs.
Search for hadronic solar axions Akhmatov, Z A; Berezin, S S; Gavrilyuk, Yu M ...
Journal of physics. Conference series,
02/2021, Letnik:
1787, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Resonance excitation of the 83Kr first nuclear level (E = 9.4 keV) by solar axions formed via the Primakoff mechanism and via an M1-transition in the 83Kr nucleus in the Sun is searched. The γ-and ...x-ray photons and the conversion and Auger electrons arising from the excited-level relaxation are detected with a proportional counter in the underground low-background facility of Baksan Neutrino Observatory. The following experimental constraint is obtained for the product of the axion-photon coupling constant and the axion mass: |gAγmA| ≼ 6.16 × 10−17. In the framework of the hadronic-axion model, this corresponds to a new axion-mass constraint of mA ≼ 12.6 eV at 95% coincidence level (C.L.). In case of pure hadronic interaction the upper limit for axion-nucleon coupling is |gAN3−gAN0| ≼ 8.3 × 10−7 at 95% C.L., which corresponds to upper limit for hadrionic axion mass: mA ≼ 64 eV at 95% C.L. with the generally accepted values S = 0.5 and z = 0.56.
We report on the study of thermal neutron flux using monitors based on mixture of ZnS(Ag) and LiF enriched with a lithium-6 isotope at the deep underground laboratory DULB-4900 at the Baksan Neutrino ...Observatory. An annual modulation of thermal neutron flux in DULB-4900 is observed. Experimental evidences were obtained of correlation between the long-term thermal neutron flux variations and the absolute humidity of the air in laboratory. The amplitude of the modulation exceed 5% of total neutron flux.
The technique used in the experiment in the search for the process of
2K2ν
-capture in
124
Xe using large high-pressure proportional counters is briefly described. The measurements with a xenon ...sample enriched to 21% (or ~57 g) of the
124
Xe isotope carried out for 3340 hours yielded a zero signal. The resultant upper limit on the
124
Xe half-life with respect to the 2ν-mode of the nuclear capture of two K-shell electrons amounts to
T
1/2
>4.6 10
21
yr at the 90% confidence level.
We describe the Monte Carlo (MC) simulation package of the "2K-CAPTURE" setup and discuss the agreement of its output with data. The "2K-CAPTURE" MC simulates the energy loss of particles in detector ...and components of the passive shield and generates the resulting response in working volume large proportional counter (LPC). The simulation accounts for absorption, reemission, and scattering of both photons and neutrons and tracks them until they either are absorbed. The algorithm proceeds with a detailed simulation of the electronics chain. The MC is tuned using data collected with radioactive calibration source deployed in the internal channel of the installation. The simulation reproduces the energy response of the detector corresponding to distribution of the generated pointwise clusters of a charge of primary ionization in LPC.
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