ﻻ يوجد ملخص باللغة العربية
We have experimentally determined the production rate of $^{39}$Ar and $^{37}$Ar from cosmic ray neutron interactions in argon at sea level. Understanding these production rates is important for argon-based dark matter experiments that plan to utilize argon extracted from deep underground because it is imperative to know what the ingrowth of $^{39}$Ar will be during the production, transport, and storage of the underground argon. These measurements also allow for the prediction of $^{39}$Ar and $^{37}$Ar concentrations in the atmosphere which can be used to determine the presence of other sources of these isotopes. Through controlled irradiation with a neutron beam that mimics the cosmic ray neutron spectrum, followed by direct counting of $^{39}$Ar and $^{37}$Ar decays with sensitive ultra-low background proportional counters, we determined that the production rate from cosmic ray neutrons at sea-level is expected to be $(759 pm 128)$ atoms/kg$_text{Ar}$/day for $^{39}$Ar, and $(51.0 pm 7.4)$ atoms/kg$_text{Ar}$/day for $^{37}$Ar. We also performed a survey of the alternate production mechanisms based on the state-of-knowledge of the associated cross-sections to obtain a total sea-level cosmic ray production rate of $(1048 pm 133)$ atoms/kg$_text{Ar}$/day for $^{39}$Ar, $(56.7 pm 7.5)$ atoms/kg$_text{Ar}$/day for $^{37}$Ar in underground argon, and $(92 pm 13)$ atoms/kg$_text{Ar}$/day for $^{37}$Ar in atmospheric argon.
We report on the measurement of the specific activity of Ar-39 in natural argon. The measurement was performed with a 2.3-liter two-phase (liquid and gas) argon drift chamber. The detector was developed by the WARP Collaboration as a prototype detect
The Aria project consists of a plant, hosting a 350 m cryogenic isotopic distillation column, the tallest ever built, which is currently in the installation phase in a mine shaft at Carbosulcis S.p.A., Nuraxi-Figus (SU), Italy. Aria is one of the pil
The DEAP-3600 detector searches for the scintillation signal from dark matter particles scattering on a 3.3 tonne liquid argon target. The largest background comes from $^{39}$Ar beta decays and is suppressed using pulseshape discrimination (PSD).
Here we present the first results of WATCHBOY, a water Cherenkov detector designed to measure the yield of $beta$-neutron emitting radionuclides produced by cosmic ray muons in water. In addition to the $beta$-neutron measurement, we also provide a f
We present transverse momentum spectra, rapidity distribution and multiplicity of Lambda-hyperons measured with the HADES spectrometer in the reaction Ar(1.76A GeV)+KCl. The yield of Xi- is calculated from our previously reported Xi-/(Lambda+Sigma0)