Fri·Sep 10, 2021Friday·September 10, 2021

1. 01*

   Sensitivity Analysis of calibration methods and factors effecting the statistical nature of radiation measurement

   Mayank Goswami · Kajal Kumari

   Scintillator detectors electronics is recalibrated against the datasheet given by the manufacturer. Optimal and mutual dependent values of (a) high voltage at PMT (Photomultiplier Tube), (b) amplifier gain, (c) average time to count the radiation particles (set by operator), and (d) number of instances/sample number are estimated. Total 5: two versions of Central Limit Theorem (CLT), (3) industry preferred Pulse Width Saturation, (4) calibration based on MPPC coupled Gamma-ray detector and (5) gross method are used. It is shown that CLT method is the most optimal method to calibrate detector and its respective electronics couple. An inverse modeling-based Computerized Tomography method is used for verification. It is shown that statistically averaging results are more accurate and precise data than mode and median, if the data is not skewed and random number of samples are used during the calibration process. It is also shown that the average time to count the radiation particle is the most important parameter affecting the optimal calibration setting for precision and accurate measurements of gamma radiation.

   ↳ physics.ins-detnucl-ex1 citation
2. 02*

   Possible antimagnetic rotation bands in ${}^{100}$Pd: a particle-number conserving investigation

   Jian-Qin Ma · Zhen-Hua Zhang🇨🇳

   The particle-number conserving method based on the cranked shell model is adopted to investigate the possible antimagnetic rotation bands in ${}^{100}$Pd. The experimental kinematic and dynamic moments of inertia, together with the $B(E2)$ values are reproduced quite well. The occupation probability of each neutron and proton orbital in the observed antimagnetic rotation band is analyzed and its configuration is confirmed. The contribution of each major shell to the total angular momentum alignment with rotational frequency in the lowest-lying positive and negative parity bands is analyzed. The level crossing mechanism of these bands is understood clearly. The possible antimagnetic rotation in the negative parity $\alpha =0$ branch is predicted, which sensitively depends on the alignment of the neutron ($1g_{7/2}$, $2d_{5/2}$) pseudo-spin partners. The two-shears-like mechanism for this antimagnetic rotation is investigated by examining the closing of the proton hole angular momentum vector towards the neutron angular momentum vector.

   ↳ nucl-thnucl-exNPA(2021)·7 citations
3. 03*

   Hidden-charm tetraquarks with strangeness in the chiral quark model

   Gang Yang🇨🇳 · Jialun Ping🇨🇳 · Jorge Segovia🇪🇸

   The hidden-charm tetraquarks with strangeness, $c\bar{c}s\bar{q}$ $(q=u,d)$, in $J^P=0^{+}$, $1^{+}$ and $2^{+}$ are systematically investigated in the framework of real- and complex-scaling range of a chiral quark model, whose parameters have been fixed in advance describing hadron, hadron-hadron and multiquark phenomenology. Each tetraquark configuration, compatible with the quantum numbers studied, is taken into account; this includes meson-meson, diquark-antidiquark and K-type arrangements of quarks with all possible color wave functions in four-body sector. Among the different numerical techniques to solve the Schrödinger-like 4-body bound state equation, we use a variational method in which the trial wave function is expanded in complex-range Gaussian basis functions, which is characterized by its simplicity and flexibility. This theoretical framework has already been used to study different kinds of multiquark systems, such as the hidden-charm pentaquarks, $P_c^{+}$, and doubly-charmed tetraquarks, $T_{cc}^{+}$. The recently reported $Z_{cs}$ states by the BESIII and LHCb collaborations are generally compatible with either compact tetraquark or hadronic molecular resonance configurations in our investigation. Moreover, several additional exotic resonances are found in the mass range between 3.8 GeV and 4.6 GeV.

   ↳ hep-phhep-exhep-latnucl-ex+1PRD(2021)·36 citations
4. 04*

   First measurement of ${\mathrm{\Omega }}_{\mathrm{c}}^0$ production in pp collisions at $\sqrt{s}=13$ TeV with ALICE

   Jianhui Zhu🇨🇳

   Recent measurements of charm-baryon production in proton--proton (pp) collisions at midrapidity by the ALICE collaboration showed that baryon-to-meson yield ratios are significantly higher than those measured in ${\mathrm{e}}^{+}{\mathrm{e}}^{-}$ collisions. The charm baryon-to-meson and charm baryon-to-baryon yield ratios provide unique information on hadronization mechanisms since the contributions from parton distribution function and parton--parton scattering terms cancel in the ratios. In this contribution, the first measurement of ${\mathrm{\Omega }}_{\mathrm{c}}^0$ production via the hadronic decay channel ${\mathrm{\Omega }}_{\mathrm{c}}^0\to {\mathrm{\Omega }}^{-}{\pi }^{+}$ (and its charge conjugate) in $2<p_{\mathrm{T}}<12$ GeV/$c$ performed with the ALICE detector at midrapidity in pp collisions at $\sqrt{s}=$ 13 TeV is presented. The ${\mathrm{\Omega }}_{\mathrm{c}}^0/{\mathrm{D}}^0$ and ${\mathrm{\Omega }}_{\mathrm{c}}^0/{\mathrm{\Xi }}_{\mathrm{c}}^0$ ratios multiplied by the decay branching ratio $\mathrm{BR}({\mathrm{\Omega }}_{\mathrm{c}}^0\to {\mathrm{\Omega }}^{-}{\pi }^{+})$, which is not experimentally measured, are compared to MC generators with fragmentation fractions based on ${\mathrm{e}}^{+}{\mathrm{e}}^{-}$ measurements and models including hadronization of charm quark via coalescence.

   ↳ hep-exnucl-exPoS(2021)·0 citations
5. 05*

   Frequency shifts in the EPR spectrum of ${}^{39}$K due to spin-exchange collisions with polarized ${}^3$He and precise ${}^3$He polarimetry

   Sumudu Katugampola (1)🇺🇸 · Christopher Jantzi (1)🇺🇸 · David A. Keder (1) · G. Wilson Miller (1 and 2) · Vladimir Nelyubin (1)🇺🇸 · Huong Nguyen (1)🇺🇸 · Sina Tafti (1) · William A. Tobias (1)🇺🇸 · Gordon D. Cates (1 and 2) ((1) Department of Physics, University of Virginia, (2) Department of Radiology and Medical Imaging, University of Virginia)🇺🇸

   The Zeeman splittings and EPR frequencies of alkali-metal atoms are shifted in the presence of a polarized noble gas. For a spherical geometry, the shift is enhanced over what is expected classically by a dimensionless atomic parameter ${\kappa }_0$ that is unique to each alkali-metal atom - noble-gas pair. We present a precise measurement of ${\kappa }_0$ for the ${}^{39}$K-${}^3$He system with a relative accuracy of better than 1\%. A critical component of achieving sub-percent accuracy involved characterizing the shape of our samples using both MRI and CT medical-imaging techniques. The parameter ${\kappa }_0$ plays an important role in establishing the absolute polarization of ${}^3$He in a variety of contexts, including polarized targets for electron scattering experiments and MRI of the gas space of the lungs. Our measurement more than doubles the accuracy possible when using ${\kappa }_0$ for polarimetry purposes. Just as important, the work presented here represents the first {\it direct} measurement of ${\kappa }_0$ for the ${}^{39}$K-${}^3$He system; previous values for ${\kappa }_0$ in the ${}^{39}$K-${}^3$He system relied on a chain of measurements that were benchmarked by previous measurements of ${\kappa }_0$ in the Rb-${}^3$He system.

   ↳ physics.atom-phnucl-exPRA(2025)·2 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.