Wed·Mar 13, 2024Wednesday·March 13, 2024

1. 01*

   Challenges in the extraction of physics beyond the Standard Model from electron scattering

   X. G. Wang🇦🇺 · A. W. Thomas🇦🇺

   Precise measurements of electron and positron scattering, including parity violation, offer great promise in the search for physics beyond the Standard Model. In this context it is crucial to understand the corrections which might arise from charge symmetry violation, as well as the less well known strange and charm quark distributions. Our analysis, using state of the art parton distributions, suggests that these contributions lead to corrections in the extraction of the weak couplings $g_{AV}^{eq}$ and $g_{VA}^{eq}$ of the order $(1-2)\%$, while they are as large as $4\%$ for $g_{AA}^{eq}$, at a typical scale of $Q^2=10{\mathrm{GeV}}^2$. These results underline the importance of carrying out high precision measurements, which will not only provide information on physics beyond the Standard Model but also reduce the current uncertainties on our knowledge of the strange and charm quark distributions in the proton.

   ↳ hep-phhep-exnucl-exJ.Phys.G(2025)·5 citations
2. 02*

   Radon Concentration Measurement with a High-Sensitivity Radon Detector at the Yemilab

   Kyungmin Seo🇰🇷 · Hyunsoo Kim🇰🇷 · Yeongduk Kim🇰🇷 · Hyeyoung Lee🇰🇷 · Jaison Lee🇰🇷 · Moo Hyun Lee🇰🇷 · Jungho So🇰🇷 · Sangcheol Yoon🇰🇷 · Youngsoo Yoon🇰🇷

   The radiation emitted from radon is a critical background in rare event search experiments conducted at the Yemi Underground Laboratory (Yemilab) in Jeongseon, Korea. A Radon Reduction System(RRS) has been developed and installed in Yemilab to reduce radon concentration in the air. The RRS primarily provides a purified air of 50 m3/h to the cleanroom used to assemble crystal detectors in the AMoRE, a neutrinoless double beta decay search experiment. RRS can reduce the radon level by a factor of 300, so a high-sensitivity radon detector was required. A highly sensitive radon detector was constructed using a 70 L chamber with a large PIN photodiode to measure radon concentration in the purified air. The radon detector shows an excellent resolution of 72 keV (FWHM) for 6.003 MeV alphas from 218Po decay and a sensitivity down to 23.8 +- 2.1 mBq/m3 with a boil-off N2 gas sample. The radon concentration level from the RRS measured by the radon detector was below 0.29 Bq/m3 with a reduction factor of about 300.

   ↳ physics.ins-detastro-ph.IMhep-exnucl-exJINST(2024)·1 citation
3. 03*

   Quenching and flow of charm and bottom quarks via semi-leptonic decay of $D$ and $B$ mesons in Pb+Pb collisions at the LHC

   Shu-Qing Li🇨🇳 · Wen-Jing Xing🇨🇳 · Shanshan Cao🇨🇳 · Guang-You Qin🇨🇳

   Heavy flavor particles provide important probes of the microscopic structure and thermodynamic properties of the quark-gluon plasma (QGP) produced in high-energy nucleus-nucleus collisions. We study the energy loss and flow of charm and bottom quarks inside the QGP via the nuclear modification factor ($R_{\mathrm{AA}}$) and elliptic flow coefficient ($v_2$) of their decayed leptons in heavy-ion collisions at the LHC. The dynamical evolution of the QGP is performed using the (3+1)-dimensional viscous hydrodynamics model CLVisc; the evolution of heavy quarks inside the QGP is simulated with our improved Langevin model that takes into account both collisional and radiative energy loss of heavy quarks; the hadronization of heavy quarks is simulated via our hybrid coalescence-fragmentation model; and the semi-leptonic decay of $D$ and $B$ mesons is simulated via PYTHIA. By using the same spatial diffusion coefficient for charm and bottom quarks, we obtain smaller $R_{\mathrm{AA}}$ and larger $v_2$ of charm decayed leptons than bottom decayed leptons, indicating stronger energy loss of charm quarks than bottom quarks inside the QGP within our current model setup.

   ↳ hep-phnucl-exnucl-thCPC(2024)·6 citations
4. 04*

   Exploring the Nuclear Shape Phase Transition in Ultra-Relativistic ${}^{129}$Xe+${}^{129}$Xe Collisions at the LHC

   Shujun Zhao🇨🇳 · Hao-jie Xu🇨🇳 · You Zhou🇩🇰 · Yu-Xin Liu🇨🇳 · Huichao Song🇨🇳

   The shape phase transition for certain isotope or isotone chains, associated with the quantum phase transition of finite nuclei, is an intriguing phenomenon in nuclear physics. A notable case is the Xe isotope chain, where the structure transits from a $\gamma$-soft rotor to a spherical vibrator, with the second-order shape phase transition occurring in the vicinity of ${}^{128-130}$Xe. In this letter, we focus on investigating the $\gamma$-soft deformation of ${}^{129}$Xe associated with the second-order shape phase transition by constructing novel correlators for ultra-relativistic ${}^{129}$Xe+${}^{129}$Xe collisions. In particular, our iEBE-VISHNU model calculations show that the $v_2^2-[p_T]$ correlation ${\rho }_2$ and the mean transverse momentum fluctuation ${\Gamma }_{p_T}$, which were previously interpreted as the evidence for the rigid triaxial deformation of ${}^{129}$Xe, can also be well explained by the $\gamma$-soft deformation of ${}^{129}$Xe. We also propose two novel correlators ${\rho }_{4,2}$ and ${\rho }_{2,4}$, which carry non-trivial higher-order correlations and show unique capabilities to distinguish between the $\gamma$-soft and the rigid triaxial deformation of ${}^{129}$Xe in ${}^{129}$Xe+${}^{129}$Xe collisions at the LHC. The present study also provides a novel way to explore the second-order shape phase transition of finite nuclei with ultra-relativistic heavy ion collisions.

   ↳ nucl-thhep-phnucl-exPRL(2024)·42 citations
5. 05*

   Probing new bosons and nuclear structure with ytterbium isotope shifts

   Menno Door🇩🇪 · Chih-Han Yeh🇩🇪 · Matthias Heinz🇩🇪 · Fiona Kirk🇩🇪 · Chunhai Lyu🇩🇪 · Takayuki Miyagi🇩🇪 · Julian C. Berengut🇦🇺 · Jacek Bieroń🇵🇱 · Klaus Blaum🇩🇪 · Laura S. Dreissen🇩🇪 · Sergey Eliseev🇩🇪 · Pavel Filianin🇩🇪 and 15 other authors

   In this Letter, we present mass-ratio measurements on highly charged Yb${}^{42+}$ ions with a precision of $4\times 10^{-12}$ and isotope-shift measurements on Yb${}^{+}$ on the ${}^2$S${}_{1/2}$ $\to$ ${}^2$D${}_{5/2}$ and ${}^2$S${}_{1/2}$ $\to$ ${}^2$F${}_{7/2}$ transitions with a precision of $4\times 10^{-9}$ for the isotopes ${}^{168,170,172,174,176}$Yb. We present a new method that allows us to extract higher-order changes in the nuclear charge distribution along the Yb isotope chain, benchmarking ab-initio nuclear structure calculations. Additionally, we perform a King plot analysis to set bounds on a fifth force in the keV$/c^2$ to MeV$/c^2$ range coupling to electrons and neutrons.

   ↳ physics.atom-phhep-phnucl-exnucl-thPRL(2025)·68 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.