Fri·Nov 3, 2023Friday·November 3, 2023

1. 01*

   Measurements of charged-particle multiplicity dependence of higher-order net-proton cumulants in $p$+$p$ collisions at $\sqrt{s}=$ 200 GeV from STAR at RHIC

   STAR Collaboration: M. I. Abdulhamid🇪🇬 · B. E. Aboona🇺🇸 · J. Adam🇨🇿 · L. Adamczyk🇵🇱 · J. R. Adams🇺🇸 · I. Aggarwal🇮🇳 · M. M. Aggarwal🇮🇳 · Z. Ahammed🇮🇳 · E. C. Aschenauer🇺🇸 · S. Aslam🇮🇳 · J. Atchison🇺🇸 · V. Bairathi🇨🇱 and 350 other authors

   We report on the charged-particle multiplicity dependence of net-proton cumulant ratios up to sixth order from $\sqrt{s}=200$ GeV $p$+$p$ collisions at the Relativistic Heavy Ion Collider (RHIC). The measured ratios $C_4/C_2$, $C_5/C_1$, and $C_6/C_2$ decrease with increased charged-particle multiplicity and rapidity acceptance. Neither the Skellam baselines nor PYTHIA8 calculations account for the observed multiplicity dependence. In addition, the ratios $C_5/C_1$ and $C_6/C_2$ approach negative values in the highest-multiplicity events, which implies that thermalized QCD matter may be formed in $p$+$p$ collisions.

   nucl-exhep-exhep-phnucl-thPLB(2024)·9 citations
2. 02*

   Electromagnetic moments of the antimony isotopes ${}^{112-133}$Sb

   S. Lechner🇨🇭 · T. Miyagi🇨🇦 · Z.Y. Xu🇧🇪 · M.L. Bissell🇬🇧 · K. Blaum🇩🇪 · B. Cheal🇬🇧 · C.S. Devlin🇬🇧 · R.F. Garcia Ruiz🇨🇭 · J.S.M. Ginges🇦🇺 · H. Heylen🇨🇭 · J.D. Holt🇨🇦 · P. Imgram🇩🇪 and 13 other authors

   Nuclear moments of the antimony isotopes ${}^{113-133}$Sb are measured by collinear laser spectroscopy and used to benchmark phenomenological shell-model and \textit{ab initio} calculations in the valence-space in-medium similarity renormalization group (VS-IMSRG). The shell-model calculations reproduce the electromagnetic moments over all Sb isotopes when suitable effective $g$-factors and charges are employed. Good agreement is achieved by VS-IMSRG for magnetic moments on the neutron-deficient side for both odd-even and odd-odd Sb isotopes while its results deviate from experiment on the neutron-rich side. When the same effective $g$-factors are used, VS-IMSRG agrees with experiment nearly as well as the shell model. Hence, the wave functions are very similar in both approaches and missing contributions to the M1 operator are identified as the cause of the discrepancy of VS-IMSRG with experiment. Electric quadrupole moments remain more challenging for VS-IMSRG.

   nucl-exnucl-thPLB(2023)·14 citations
3. 03*

   Direct demonstration of the two-phonon structure of the $J^{\pi }=1_{4742\mathrm{keV}}^{-}$ state of ${}^{88}$Sr

   J. Isaak🇩🇪 · D. Savran · N. Pietralla🇩🇪 · N. Tsoneva · A. Zilges · K. Eberhardt · C. Geppert · C. Gorges🇩🇪 · H. Lenske🇩🇪 · D. Renisch🇩🇪

   We have studied the decay pattern of the $J^{\pi }=1_{4742\mathrm{keV}}^{-}$ state of ${}^{88}$Sr to probe its quadrupole-octupole coupled two-phonon structure. In particular, a unique fingerprint to prove the two-phonon nature is the $E2$ decay strength of the $1_{4742\mathrm{keV}}^{-}\to 3_1^{-}$ transition into the one-octupole-phonon state. $\gamma$-ray spectroscopy was performed after the $\beta$-decay of ${}^{88}$Rb to obtain the necessary sensitivity for this weak-intensity decay branch. Sufficient amounts of ${}^{88}$Rb (T${}_{1/2}$ = 17.8 min) were produced by neutron activation of natural Rb in the TR IGA Mark II reactor. The results show that the $B(E2)$ value of the $1_{4742\mathrm{keV}}^{-}\to 3_1^{-}$ transition is equal to the $B(E2)$ of the $2_1^{+}\to 0_1^{+}$ transition, directly demonstrating the quadrupole-octupole coupled two-phonon nature of the $1^{-}$ state. A comparison of the results with energy-density functional plus quasiparticle-phonon model calculations shows rema rkable agreement, corroborating this assignment.

   nucl-exPRC(2023)·6 citations
4. 04*

   The CeBrA demonstrator for particle-$\gamma$ coincidence experiments at the FSU Super-Enge Split-Pole Spectrograph

   A.L. Conley🇺🇸 · B. Kelly🇺🇸 · M. Spieker🇺🇸 · R. Aggarwal🇮🇳 · S. Ajayi🇺🇸 · L.T. Baby🇺🇸 · S. Baker🇺🇸 · C. Benetti · I. Conroy🇬🇧 · P.D. Cottle🇺🇸 · I.B. D`Amato · P. DeRosa and 21 other authors

   We report on a highly selective experimental setup for particle-$\gamma$ coincidence experiments at the Super-Enge Split-Pole Spectrograph (SE-SPS) of the John D. Fox Superconducting Linear Accelerator Laboratory at Florida State University (FSU) using fast CeBr${}_3$ scintillators for $\gamma$-ray detection. Specifically, we report on the results of characterization tests for the first five CeBr${}_3$ scintillation detectors of the CeBr${}_3$ Array (CeBrA) with respect to energy resolution and timing characteristics. We also present results from the first particle-$\gamma$ coincidence experiments successfully performed with the CeBrA demonstrator and the FSU SE-SPS. We show that with the new setup, $\gamma$-decay branching ratios and particle-$\gamma$ angular correlations can be measured very selectively using narrow excitation energy gates, which are possible thanks to the excellent particle energy resolution of the SE-SPS. In addition, we highlight that nuclear level lifetimes in the nanoseconds regime can be determined by measuring the time difference between particle detection with the SE-SPS focal-plane scintillator and $\gamma$-ray detection with the fast CeBrA detectors. Selective excitation energy gates with the SE-SPS exclude any feeding contributions to these lifetimes.

   ↳ physics.ins-detnucl-exNucl.Instrum.Meth.A(2024)·9 citations
5. 05*

   Study of bulk properties of the system formed in U+U collisions at $\sqrt{s_{\mathrm{N}N}}$ =~2.12~GeV using JAM model

   Aswini Kumar Sahoo🇮🇳 · Xionghong He🇨🇳 · Yasushi Nara🇯🇵 · Subhash Singha🇨🇳

   The Lanzhou Cooling-Storage-Ring facility is set to conduct experiments involving Uranium-Uranium collisions at the center of mass energies ranging from 2.12 to 2.4 GeV. Our investigation is focused on various bulk observables, which include charged particle multiplicity ($N_{\text{ch}}$), average transverse momentum ($⟨p_{\text{T}}⟩$), initial eccentricity (${ϵ}_n$), and flow harmonics ($v_n$), for different orientations of U+U collisions within the range of $0^{\circ }<\theta <120^{\circ }$ at $\sqrt{s_{\mathrm{N}N}}=2.12$ GeV ($p_{\mathrm{l}ab}$ = 500 MeV). Among the various collision configurations at this energy, the tip-tip scenario emerged with the highest average charged particle multiplicity, denoted as $⟨N_{\text{ch}}⟩$. Notably, both the second and third-order eccentricities, ${ϵ}_{2,3}$, revealed intricate patterns as they varied with impact parameter across distinct configurations. The tip-tip configuration displayed the most pronounced magnitude of rapidity-odd directed flow ($v_1$), whereas the body-body configuration exhibited the least pronounced magnitude. Concerning elliptic flow ($v_2$) near mid-rapidity ($\eta <1.0$), a negative sign is observed for all configurations except for the side-side exhibited a distinctly positive sign. Within the spectrum of configurations, the body-body scenario displayed the highest magnitude of $v_2$. For reaction plane correlated triangular flow ($v_3$), the body-body configuration emerged with the largest magnitude while the side-side exhibited the smallest magnitude. Our study seeks to establish a fundamental understanding of various U+U collision configurations in preparation for the forthcoming CEE experiment.

   ↳ nucl-thhep-exnucl-exPRC(2024)·2 citations
6. 06*

   Hidden-charm pentaquarks with strangeness in a chiral quark model

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

   The LHCb collaboration has recently announced the discovery of two hidden-charm pentaquark states with also strange quark content, $P_{cs}(4338)$ and $P_{cs}(4459)$; its analysis points towards having both hadrons isospin equal to zero and spin-parity quantum numbers ${\frac{1}{2}}^{-}$ and ${\frac{3}{2}}^{-}$, respectively. We perform herein a systematical investigation of the $qqsc\bar{c}$ $(q=u,d)$ system by means of a chiral quark model, along with a highly accurate computational method, the Gaussian expansion approach combined with the complex-scaling technique. Baryon-meson configurations in both singlet- and hidden-color channels are considered. The $P_{cs}(4338)$ and $P_{cs}(4459)$ signals can be well identified as molecular bound states with dominant components $\Lambda J/\psi$ $(60\%)$ and ${\Xi }_{c}D$ $(23\%)$ for the lowest-energy case and ${\Xi }_c{D}^{\ast }$ $(72\%)$ for the highest-energy one. Besides, it seems that some narrow resonances can be also found in each allowed $I(J^P)$-channel in the energy region of $4.6-5.5$ GeV, except for the $1({\frac{1}{2}}^{-})$ where a shallow bound state with dominant ${\Xi }_c^{\ast }{D}^{\ast }$ structure is obtained at $4673$ MeV with binding energy $E_B=-3$ MeV. These exotic states are expected to be confirmed in future high energy experiments.

   ↳ hep-phhep-exhep-latnucl-ex+1Symmetry(2024)·14 citations
7. 07*

   Improving the Performance of Cryogenic Calorimeters with Nonlinear Multivariate Noise Cancellation Algorithms

   Kenneth J. Vetter (1 and 2)🇺🇸 · Mattia Beretta (1 and 2)🇺🇸 · Chiara Capelli (2)🇺🇸 · Francesca Del Corso (3 and 4)🇮🇹 · Erin V. Hansen (1 and 2)🇺🇸 · Roger G. Huang (1 and 2)🇺🇸 · Yury G. Kolomensky (1 and 2)🇺🇸 · Laura Marini (5 and 6)🇮🇹 · Irene Nutini (7 and 8)🇮🇹 · Vivek Singh (1 and 2)🇺🇸 · Aaron Torres (1 and 9)🇺🇸 · Bradford Welliver (1 and 2)🇺🇸 · Sergio Zimmermann (9)🇺🇸 · Stefano Zucchelli (3 and 4) ((1) Department of Physics, University of California Berkeley, Berkeley, CA, USA (2) Nuclear Science Division, Lawrence Berkeley National Lab, Berkeley, CA USA (3) Dipartimento di Fisica e Astronomia, Alma Mater Studiorum -- Universita di Bologna, Bologna, Italy (4) INFN -- Sezione di Bologna, Bologna, Italy (5) Gran Sasso Science Institute, L'Aquila, Italy (6) INFN -- Laboratori Nazionali del Gran Sasso, Assergi, AQ, Italy (7) INFN -- Sezione di Milano Bicocca, Milano, Italy (8) Dipartimento di Fisica, Universita di Milano-Bicocca, Milano, Italy (9) Engineering Division, Lawrence Berkeley National Lab, Berkeley, CA, USA)🇮🇹

   State-of-the-art physics experiments require high-resolution, low-noise, and low-threshold detectors to achieve competitive scientific results. However, experimental environments invariably introduce sources of noise, such as electrical interference or microphonics. The sources of this environmental noise can often be monitored by adding specially designed "auxiliary devices" (e.g. microphones, accelerometers, seismometers, magnetometers, and antennae). A model can then be constructed to predict the detector noise based on the auxiliary device information, which can then be subtracted from the true detector signal. Here, we present a multivariate noise cancellation algorithm which can be used in a variety of settings to improve the performance of detectors using multiple auxiliary devices. To validate this approach, we apply it to simulated data to remove noise due to electromagnetic interference and microphonic vibrations. We then employ the algorithm to a cryogenic light detector in the laboratory and show an improvement in the detector performance. Finally, we motivate the use of nonlinear terms to better model vibrational contributions to the noise in thermal detectors. We show a further improvement in the performance of a particular channel of the CUORE detector when using the nonlinear algorithm in combination with optimal filtering techniques.

   ↳ physics.ins-detnucl-exEPJC(2024)·13 citations
8. 08*

   Pushing the high count rate limits of scintillation detectors for challenging neutron-capture experiments

   J. Balibrea Correa · J. Lerendegui-Marco · V. Babiano-Suarez · C. Domingo-Pardo · I. Ladarescu · A. Tarifeño-Saldivia · V. Alcayne · D. Cano-Ott · E. González-Romero · T. Martínez · E. Mendoza · A. Pérez de Rada and 122 other authors

   One of the critical aspects for the accurate determination of neutron capture cross sections when combining time-of-flight and total energy detector techniques is the characterization and control of systematic uncertainties associated to the measuring devices. In this work we explore the most conspicuous effects associated to harsh count rate conditions: dead-time and pile-up effects. Both effects, when not properly treated, can lead to large systematic uncertainties and bias in the determination of neutron cross sections. In the majority of neutron capture measurements carried out at the CERN n\_TOF facility, the detectors of choice are the C${}_6$D${}_6$ liquid-based either in form of large-volume cells or recently commissioned sTED detector array, consisting of much smaller-volume modules. To account for the aforementioned effects, we introduce a Monte Carlo model for these detectors mimicking harsh count rate conditions similar to those happening at the CERN n\_TOF 20~m fligth path vertical measuring station. The model parameters are extracted by comparison with the experimental data taken at the same facility during 2022 experimental campaign. We propose a novel methodology to consider both, dead-time and pile-up effects simultaneously for these fast detectors and check the applicability to experimental data from ${}^{197}$Au($n$,$\gamma$), including the saturated 4.9~eV resonance which is an important component of normalization for neutron cross section measurements.

   ↳ physics.ins-detnucl-exNucl.Instrum.Meth.A(2024)·5 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.