Tue·Oct 18, 2022Tuesday·October 18, 2022

1. 01*

   Shake-up and shake-off effects in neutrinoless double-beta decay

   J.A. Detwiler🇺🇸 · R.G.H. Robertson🇺🇸

   We revisit the role of shake-up and shake-off effects in neutrinoless double-beta decay, following earlier work by Drukarev et al. We find in agreement with Drukarev et al. that the Q value of the decay is reduced by any atomic excitation in the final-state but not by the difference in atomic binding energy of the initial and final state atoms, as was recently suggested by Mei and Wei. We discuss how the absorption of subsequent atomic de-excitation ejecta shifts the neutrinoless double-beta decay peak back to its nominal value. We propose an in situ experimental verification of these ideas, and discuss the impact of shake-up and shake-off on two-neutrino double-beta decay spectral shapes.

   nucl-exhep-phPRC(2023)·4 citations
2. 02*

   \psi(2S) production as a function of charged-particle multiplicity in pp collisions at $\sqrt{s}$= 13 TeV and p--Pb collisions at $\sqrt{s_{\mathrm{NN}}}$= 8.16 TeV with ALICE at the LHC

   Theraa Tork (for the ALICE collaboration)🇫🇷

   The self-normalised $\psi (2S)$ yields as a function of charged-particle multiplicity in pp collisions at $\sqrt{s}$ = 13 TeV and p--Pb collisions at $\sqrt{s_{\mathrm{NN}}}$= 8.16 TeV, using the ALICE detector at the CERN LHC, are reported in these proceedings. This measurement represents one of the main tools to understand the role of multiparton interactions and their influence on charmonium production in small systems, i.e pp and pA collisions. The ratio of $\psi (2S)$-over-J/$\psi$ as a function of charged-particle multiplicity is also presented for both pp and p--Pb collisions. The comparison to theoretical calculations is reported.

   nucl-exhep-exPoS(2023)·0 citations
3. 03*

   $\psi (2S)$ suppression in Pb-Pb collisions at the LHC

   ALICE Collaboration

   The production of the $\psi (2S)$ charmonium state was measured with ALICE in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV, in the dimuon decay channel. A significant signal was observed for the first time at LHC energies down to zero transverse momentum, at forward rapidity ($2.5<y<4$). The measurement of the ratio of the inclusive production cross sections of the $\psi (2S)$ and J/$\psi$ resonances is reported as a function of the centrality of the collisions and of transverse momentum, in the region $p_{\mathrm{T}}<12$ GeV/$c$. The results are compared with the corresponding measurements in pp collisions, by forming the double ratio $[{\sigma }^{\psi (2S)}/{\sigma }^{J/\psi }{]}_{\mathrm{Pb}-\mathrm{Pb}}/[{\sigma }^{\psi (2S)}/{\sigma }^{J/\psi }{]}_{\mathrm{pp}}$. It is found that in Pb-Pb collisions the $\psi (2S)$ is suppressed by a factor of $\sim 2$ with respect to the J/$\psi$. The $\psi (2S)$ nuclear modification factor $R_{\mathrm{AA}}$ was also obtained as a function of both centrality and $p_{\mathrm{T}}$. The results show that the $\psi (2S)$ resonance yield is strongly suppressed in Pb-Pb collisions, by a factor up to $\sim 3$ with respect to pp. Comparisons of cross section ratios with previous SPS findings by the NA50 experiment and of $R_{\mathrm{AA}}$ with higher-$p_{\mathrm{T}}$ results at LHC energy are also reported. These results and the corresponding comparisons with calculations of transport and statistical models address questions on the presence and properties of charmonium states in the quark-gluon plasma formed in nuclear collisions at the LHC.

   nucl-exhep-exPRL(2024)·86 citations
4. 04*

   Measurements of azimuthal anisotropies at forward and backward rapidity with muons in high-multiplicity p-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=8.16$ TeV

   ALICE Collaboration

   The study of the azimuthal anisotropy of inclusive muons produced in p-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=8.16$ TeV, using the ALICE detector at the LHC is reported. The measurement of the second-order Fourier coefficient of the particle azimuthal distribution, $v_2$, is performed as a function of transverse momentum $p_{\mathrm{T}}$ in the 0-20% high-multiplicity interval at both forward ($2.03<y_{\mathrm{CMS}}<3.53$) and backward ($-4.46<y_{\mathrm{CMS}}<-2.96$) rapidities over a wide $p_{\mathrm{T}}$ range, $0.5<p_{\mathrm{T}}<10$ GeV/$c$, in which a dominant contribution of muons from heavy-flavour hadron decays is expected at $p_{\mathrm{T}}>2$ GeV/$c$. The $v_2$ coefficient of inclusive muons is extracted using two different techniques, namely two-particle cumulants, used for the first time for heavy-flavour measurements, and forward-central two-particle correlations. Both techniques give compatible results. A positive $v_2$ is measured at both forward and backward rapidities with a significance larger than $4.7\sigma$ and $7.6\sigma$, respectively, in the interval $2<p_{\mathrm{T}}<6$ GeV/$c$. Comparisons with previous measurements in p-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV, and with AMPT and CGC-based theoretical calculations are discussed. The findings impose new constraints on the theoretical interpretations of the origin of the collective behaviour in small collision systems.

   nucl-exhep-exPLB(2023)·18 citations
5. 05*

   Azimuthal anisotropy of dijet events in PbPb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV

   CMS Collaboration

   The path-length dependent parton energy loss within the dense partonic medium created in lead-lead collisions at a nucleon-nucleon center-of-mass energy of $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV is studied by determining the azimuthal anisotropies for dijets with high transverse momentum. The data were collected by the CMS experiment in 2018 and correspond to an integrated luminosity of 1.69 nb${}^{-1}$. For events containing back-to-back jets, correlations in relative azimuthal angle and pseudorapidity ($\eta$) between jets and hadrons, and between two hadrons, are constructed. The anisotropies are expressed as the Fourier expansion coefficients $v_n$, $n=$ 2-4 of these azimuthal distributions. The dijet $v_n$ values are extracted from long-range (1.5 $<$ $|\Delta \eta |$ $<$ 2.5) components of these correlations, which suppresses the background contributions from jet fragmentation processes. Positive dijet $v_2$ values are observed which increase from central to more peripheral events, while the $v_3$ and $v_4$ values are consistent with zero within experimental uncertainties.

   ↳ hep-exnucl-exJHEP(2023)·16 citations
6. 06*

   Model Independent Approach of the JUNO ${}^8$B Solar Neutrino Program

   JUNO Collaboration: Jie Zhao · Baobiao Yue · Haoqi Lu · Yufeng Li · Jiajie Ling · Zeyuan Yu · Angel Abusleme · Thomas Adam · Shakeel Ahmad · Rizwan Ahmed · Sebastiano Aiello · Muhammad Akram and 591 other authors

   The physics potential of detecting ${}^8$B solar neutrinos will be exploited at the Jiangmen Underground Neutrino Observatory (JUNO), in a model independent manner by using three distinct channels of the charged-current (CC), neutral-current (NC) and elastic scattering (ES) interactions. Due to the largest-ever mass of ${}^{13}$C nuclei in the liquid-scintillator detectors and the {expected} low background level, ${}^8$B solar neutrinos would be observable in the CC and NC interactions on ${}^{13}$C for the first time. By virtue of optimized event selections and muon veto strategies, backgrounds from the accidental coincidence, muon-induced isotopes, and external backgrounds can be greatly suppressed. Excellent signal-to-background ratios can be achieved in the CC, NC and ES channels to guarantee the ${}^8$B solar neutrino observation. From the sensitivity studies performed in this work, we show that JUNO, with ten years of data, can reach the {1$\sigma$} precision levels of 5%, 8% and 20% for the ${}^8$B neutrino flux, ${\sin }^2{\theta }_{12}$, and $\Delta m_{21}^2$, respectively. It would be unique and helpful to probe the details of both solar physics and neutrino physics. In addition, when combined with SNO, the world-best precision of 3% is expected for the ${}^8$B neutrino flux measurement.

   ↳ hep-exastro-ph.SRhep-phnucl-exApJ(2024)·36 citations
7. 07*

   ARIEL experiments and theory

   Petr Navratil🇨🇦

   I present an overview of experiments at TRIUMF ARIEL and ISAC facilities covering both the current and the future envisioned programs. I also briefly review theory program at TRIUMF that relates to the ARIEL experimental program. I highlight several recent experimental results from the nuclear astrophysics, nuclear structure, fundamental symmetries, and the sterile neutrino search. Finally, I mention ongoing theoretical ab initio calculations of the proton capture on 7Li related to the X17 boson observation.

   ↳ nucl-thnucl-exJ.Phys.Conf.Ser.(2022)·4 citations
8. 08*

   Constraints on the nuclear Schiff moment from its correlation with electromagnetic properties

   K. Yanase🇯🇵 · N. Shimizu🇯🇵 · K. Higashiyama · N. Yoshinaga

   We study the nuclear Schiff moments of ${}^{129}$Xe and ${}^{199}$Hg induced by the nucleon electric dipole moment using large-scale shell model calculations. For ${}^{129}$Xe, we find a linear relation between the leading-order contribution and magnetic moment, which would be useful in reducing the theoretical uncertainty. The conventional model space does not contain the $0g_{9/2}$ and $0h_{9/2}$ orbitals, which are connected to the spin-orbit partners by large matrix elements. Thus, to evaluate the influence of the relevant single-particle orbitals outside the conventional model space, we apply the quasiparticle vacua shell model method. Moreover, the next-to-leading-order contribution arises from parity and time-reversal violation inside the nucleus. We demonstrate that these secondary effects do not induce any significant disturbance to the correlation. Additionally, we report the shell model results for the nuclear Schiff moment coefficients of ${}^{199}$Hg. Compared to previous studies, the results obtained in this study are rather large, indicating a higher sensitivity to the neutron electric dipole moment.

   ↳ nucl-thhep-exhep-phnucl-exPLB(2023)·10 citations
9. 09*

   Search for medium effects using jets from bottom quarks in PbPb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV

   CMS Collaboration

   The first study of the shapes of jets arising from bottom (b) quarks in heavy ion collisions is presented. Jet shapes are studied using charged hadron constituents as a function of their radial distance from the jet axis. Lead-lead (PbPb) collision data at a nucleon-nucleon center-of-mass energy of $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV were recorded by the CMS detector at the LHC, with an integrated luminosity of 1.69 nb${}^{-1}$. Compared to proton-proton collisions, a redistribution of the energy in b jets to larger distances from the jet axis is observed in PbPb collisions. This medium-induced redistribution is found to be substantially larger for b jets than for inclusive jets.

   ↳ hep-exnucl-exPLB(2023)·17 citations
10. 10*

    Probing gluon TMDs with reconstructed and tagged heavy flavor hadron pairs at EIC

    Xin Dong🇺🇸 · Yuanjing Ji🇺🇸 · Matthew Kelsey🇺🇸 · Sooraj Radhakrishnan🇺🇸 · Ernst Sichtermann🇺🇸 · Yuxiang Zhao🇨🇳

    Study of the transverse structure of the proton is one of the major physics goals of the upcoming Electron Ion Collider (EIC). The gluon transverse momentum dependent distributions (TMD) form an essential focus of this effort and are important towards understanding the angular momentum contribution to proton spin as well as QCD factorization. However, very limited experimental constraints on the gluon TMD exist currently. As the heavy quark production in lepton-nucleon DIS gets a dominant contribution from the photon-gluon-fusion process, heavy quark production makes an attractive tool to probe gluon distributions in nucleons. In this paper we present a study of heavy flavor hadron pair reconstruction at a future EIC detector with MAPS based inner tracking and vertexing subsystems to constrain gluon TMD. We utilize the excellent track pointing resolution provided by the detector to exclusively reconstruct heavy flavor hadron pairs via their hadronic decay channels and also to develop a heavy flavor hadron tagging algorithm. Statistical uncertainty projections on azimuthal asymmetries corresponding to gluon TMD at the EIC is evaluated. The heavy flavor tagging is found to substantially enhance the purity of heavy flavor hadron pair selection, and the statistical precision of the measurement compared to that from exclusive reconstruction. The correlation between the azimuthal angle of the transverse momentum of the gluon initiating the process and that of the corresponding heavy flavor hadron pair was also studied and found to be well correlated. This study opens up heavy flavor hadron pair measurements as an attractive channel to access gluon TMD at the EIC.

    ↳ hep-phnucl-exnucl-thphysics.ins-detPRD(2023)·3 citations
11. 11*

    Application of R-matrix and Lagrange-mesh methods to nuclear transfer reactions

    Shubhchintak🇧🇪 · P. Descouvemont🇧🇪

    Background: Nuclear transfer reactions are a useful tool to study the structure of a nucleus. For reactions involving weekly bound nuclei, breakup effects can play significant role and theoretical calculations can be computational expensive in such cases. Purpose: To utilize the Lagrange-mesh and R-matrix methods for nuclear transfer reactions. Methods: We use the adiabatic distorted wave approximation (ADWA) method which can approximately treats the breakup effects in a simpler manner. In our approach, we apply the R-matrix method combining it with the Lagrange-mesh method, which is known to provide the fast and accurate computations. Results: As a test case, we calculate the angular distribution of the cross sections for the 54Fe(d, p)55Fe reaction, where deuteron breakup effects play important role. Conclusions: We show that these methods work well in the ADWA framework, and we look forward to applying these methods in coupled channel calculations.

    ↳ nucl-thnucl-exJ. Nucl. Phys. Mat. Sci. Rad. A. Vol. 9, …·0 citations
12. 12*

    Ab initio single-neutron spectroscopic overlaps in lithium isotopes

    G. H. Sargsyan🇺🇸 · K. D. Launey🇺🇸 · R. M. Shaffer · S. T. Marley🇺🇸 · N. Dudeck · A. Mercenne🇺🇸 · T. Dytrych🇺🇸 · J. P. Draayer🇺🇸

    We calculate single-neutron spectroscopic overlaps for lithium isotopes in the framework of the \textit{ab initio} symmetry-adapted no-core shell model. We report the associated neutron-nucleus asymptotic normalization coefficients (ANCs) and spectroscopic factors (SFs) that are important ingredients in many reaction cross section calculations. While spectroscopic factors have been traditionally extracted from experimental cross sections, their sensitivity on the type of reactions, energy, and the underlying models point to the need for determining SF from first-principle structure considerations. As illustrative examples, we present ${}^6$Li+n, ${}^7$Li+n, and ${}^8$Li+n, and we show that the results are in a good agreement with those of other \textit{ab initio} methods, where available, including the quantum Monte Carlo approach. We compare ANCs and SFs to available experimentally deduced values, with a view toward expanding this study to heavier nuclei and to extracting inter-cluster effective interactions for input into analyses of existing and future experimental data.

    ↳ nucl-thnucl-exPRC(2023)·9 citations
13. 13*

    Beautiful and Charming Energy Correlators

    Evan Craft🇺🇸 · Kyle Lee🇺🇸 · Bianka Meçaj🇺🇸 · Ian Moult🇺🇸

    Understanding the detailed structure of energy flow within jets, a field known as jet substructure, plays a central role in searches for new physics, and precision studies of QCD. Many applications of jet substructure require an understanding of jets initiated by heavy quarks, whose description has lagged behind remarkable recent progress for massless jets. In this Letter, we initiate a study of correlation functions of energy flow operators on beauty and charm jets to illuminate the effects of the intrinsic mass of the elementary particles of QCD. We present a factorization theorem incorporating the mass of heavy quarks, and show that the heavy quark jet functions for energy correlators have a simple structure in perturbation theory. Our results achieve the very first full next-to-leading-logarithmic calculation of the heavy quark jet substructure observable at the LHC. Using this framework, we study the behavior of the correlators, and show that they exhibit a clear transition from a massless scaling regime, at precisely the scale of the heavy quark mass. This manifests the long-sought-after dead-cone effect and illustrates fundamental effects from the intrinsic mass of beauty and charm quarks in a perturbative regime, before they are confined inside hadrons. Our theoretical framework for studying energy correlators using heavy jets has many exciting applications for improving the description of mass effects in next generation parton shower event generators, probing the QGP, and studying heavy flavor fragmentation functions.

    ↳ hep-phhep-exnucl-exnucl-thPRD(2026)·100 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.