分类: 物理学 >> 核物理学 提交时间: 2023-08-29
摘要: The sensitivity of an experiment to detect the Majorana neutrino mass via neutrinoless double beta decay (0) strongly depends on the rate of background events that can mimic this decay. One major source of this background is the radioactive emissions from the laboratory environment. In our study, we focused on assessing the background contributions from environmental gamma rays, neutrons, and underground muons to the Jinping bolometric demonstration experiment. This experiment uses an array of lithium molybdate crystal bolometers to probe the potential 0 decay of the 100Mo isotope at the China Jinping Underground Laboratory. We also evaluated the shielding effectiveness of the experimental setup through an attenuation study. Our simulations indicate that the combined background from environmental gamma rays, neutrons, and muons in the relevant 100Mo 0 Q-value region can be reduced to approximately 0.003 cts/kg/keV/yr.
分类: 物理学 >> 核物理学 提交时间: 2023-06-27
摘要: In nuclear collisions at RHIC energies, an excess of $\Omega$ hyperons over $\overline{\Omega}$ is observed, indicating that $\Omega$ carries a net baryon number despite $s$ and $\bar{s}$ quarks being produced in pairs. The baryon number in $\Omega$ could have been transported from the incident nuclei and/or acquired and balanced in baryon pair productions associated with other types of anti-hyperons, such as $\overline{\Xi}$. To investigate these two scenarios, we propose to measure correlations between $\Omega$ and $K$, as well as between $\Omega$ and anti-hyperons. We will use two versions, the default and string-melting, of a multiphase transport (AMPT) model to illustrate the correlation method. We will present the $\Omega$-hadron correlations from simulated Au+Au collisions at $\sqrt{s_{NN}} = 7.7$ and 14.6 GeV, and discuss the dependence on collision energy and on the hadronization scheme in these two AMPT versions. These correlations from the AMPT model provide a baseline for experimental exploration of the dynamics of baryon number transport and the effects of baryon number and strangeness conservation in nuclear collisions.