Mon·Oct 3, 2022Monday·October 3, 2022

1. 01*

   Comments on Systematic Effects in the NIST Beam Neutron Lifetime Experiment

   F. E. Wietfeldt🇺🇸 · R. Biswas · J. Caylor🇺🇸 · B. Crawford · M. S. Dewey🇺🇸 · N. Fomin🇺🇸 · G. L. Greene🇺🇸 · C. C. Haddock🇺🇸 · S. F. Hoogerheide🇺🇸 · H. P. Mumm🇺🇸 · J. S. Nico🇺🇸 · W. M. Snow🇺🇸 · J. Zuchegno

   We discuss issues raised by Serebrov, et al. in a recent paper regarding systematic effects in the beam neutron lifetime experiment performed at NIST. We show that these effects were considered in the original analyses and that our corrections and systematic uncertainties were appropriate. We point out some misconceptions and erroneous assumptions in the analysis of Serebrov, et al. None of the issues raised in Serebrov, et al lead us to alter the value of the neutron lifetime reported previously.

   nucl-exphysics.ins-det4 citations
2. 02*

   Laser Spectroscopy for the Study of Exotic Nuclei

   X. F. Yang🇨🇳 · S. J. Wang🇨🇳 · S. G. Wilkins🇺🇸 · R. F. Garcia Ruiz🇺🇸

   Investigation into the properties and structure of unstable nuclei far from stability remains a key avenue of research in modern nuclear physics. These efforts are motivated by the continual observation of unexpected structure phenomena in nuclei with unusual proton-to-neutron ratios. In recent decades, laser spectroscopy techniques have made significant contributions in our understanding of exotic nuclei in different mass regions encompassing almost the entire nuclear chart. This is achieved through determining multiple fundamental properties of nuclear ground and isomeric states, such as nuclear spins, magnetic dipole and electric quadrupole moments and charge radii, via the measurement of hyperfine structures and isotope shifts in the atomic or ionic spectra of the nuclei of interest. These properties, when measured with sufficient precision for a long range of isotopes, offer prominent tests of recently developed state-of-the-art theory and help to stimulate new developments to improve the many-body methods and nucleon-nucleon interactions at the core of these models. With the aim of exploring more exotic short-lived nuclei located ever closer to the proton and neutron driplines, laser spectroscopy techniques, with their continuous technological developments towards higher resolution and higher sensitivity, are extensively employed at current- and next-generation radioactive ion beam facilities worldwide. Ongoing efforts in parallel promise to make even more exotic species available for study at next-generation facilities. Very recently, an innovative application of laser spectroscopy on molecules containing short-lived nuclei has been demonstrated offering additional opportunities for several fields of research, e.g. fundamental symmetry studies and astrophysics.

   nucl-exnucl-thPPNP(2023)·154 citations
3. 03*

   Photon-photon fusion and tau g-2 measurement in ATLAS

   Agnieszka Ogrodnik (for the ATLAS Collaboration)🇵🇱

   Relativistic heavy-ion beams at the LHC are accompanied by a large flux of equivalent photons. New measurements of exclusive dilepton production (electron, muon, and tau pairs) performed by the ATLAS experiment are discussed. We present the photon-induced production of tau pairs and constraints on the tau lepton's anomalous magnetic dipole moment. In addition, measurements of photon-induced electron and muon pair production are presented, which provide strong constraints on the nuclear photon flux and its dependence on the impact parameter and photon energy. Forward neutrons are utilised to provide an experimental handle on the impact parameter range sampled in the events.

   nucl-exhep-exSciPost Phys.Proc.(2024)·1 citation
4. 04*

   Collectivity in ultra-peripheral heavy-ion collisions

   Chun Shen🇺🇸 · Wenbin Zhao🇺🇸 · Björn Schenke🇺🇸

   We present full (3+1)D dynamical simulations to study collective behavior in ultra-peripheral nucleus-nucleus collisions (UPC) at the Large Hadron Collider (LHC) with the 3DGlauber+MUSIC+UrQMD framework. By extrapolating from asymmetric p+Pb collisions, we simulate a quasi-real photon ${\gamma }^{\ast }$ interacting with the Pb nucleus in an ultra-peripheral collision at the LHC, assuming strong final-state effects. We study the elliptic flow hierarchy between p+Pb and ${\gamma }^{\ast }$+Pb collisions, which is dominated by the difference in longitudinal flow decorrelations. Our theoretical framework provides a quantitative tool to study collectivity in small asymmetric collision systems at current and future collider experiments.

   ↳ nucl-thhep-phnucl-exEPJ Web Conf.(2023)·3 citations
5. 05*

   New Limits on Spontaneous Wave Function Collapse Models with the XENONnT Data

   Inwook Kim🇺🇸

   We have analyzed recently published XENONnT data for the spontaneous X-ray emission signature predicted by the objective wave function collapse model of quantum mechanics. With extremely low background and large exposure, XENONnT data can be used to completely exclude the theoretically predicted collapse parameters of continuous spontaneous localization~(CSL) model suggested by Ghirardi, Rhimini and Weber. Our result strongly suggests that the simplest version of the CSL model with the white-noise assumption is unlikely to provide answers to the long-standing measurement problem of quantum mechanics and motivates pursuits of more complex versions of the theory. If the result is interpreted with the Diósi-Penrose gravitational wave function collapse model, our limit improves the previous limit by a factor of 5.7. Detailed analysis using more precise background modelling can further improve the limits.

   ↳ quant-phnucl-ex0 citations
6. 06*

   X-ray performance of a customized large-format scientifc CMOS detector

   Qinyu Wu · Zhenqing Jia🇨🇳 · Wenxin Wang · Zhixing Ling · Chen Zhang🇺🇸 · Shuangnan Zhang🇨🇳 · Weimin Yuan🇮🇹

   In recent years, the performance of Scientifc Complementary Metal Oxide Semiconductor (sCMOS) sensors has been improved signifcantly. Compared with CCD sensors, sCMOS sensors have various advantages, making them potentially better devices for optical and X-ray detection, especially in time-domain astronomy. After a series of tests of sCMOS sensors, we proposed a new dedicated high-speed, large-format X-ray detector in 2016 cooperating with Gpixel Inc. This new sCMOS sensor has a physical size of 6 cm by 6 cm, with an array of 4096 by 4096 pixels and a pixel size of 15 um. The frame rate is 20.1 fps under current condition and can be boosted to a maximum value around 100 fps. The epitaxial thickness is increased to 10 um compared to the previous sCMOS product. We show the results of its frst taped-out product in this work. The dark current of this sCMOS is lower than 10 e/pixel/s at 20C, and lower than 0.02 e/pixel/s at -30C. The Fixed Pattern Noise (FPN) and the readout noise are lower than 5 e in high-gain situation and show a small increase at low temperature. The energy resolution reaches 180.1 eV (3.1%) at 5.90 keV for single-pixel events and 212.3 eV (3.6%) for all split events. The continuous X-ray spectrum measurement shows that this sensor is able to response to X-ray photons from 500 eV to 37 keV. The excellent performance, as demonstrated from these test results, makes sCMOS sensor an ideal detector for X-ray imaging and spectroscopic application.

   ↳ astro-ph.IMhep-exnucl-exphysics.ins-detPubl.Astron.Soc.Pac.(2022)·19 citations
7. 07*

   Applications of Persistent Homology in Nuclear Collisions

   Greg Hamilton🇺🇸 · Travis Dore🇺🇸 · Christopher Plumberg🇺🇸

   We introduce a novel set of observables associated to the rapidly developing field of persistent homology for the quantitative characterization of nuclear collisions and their evolution. Persistent homology allows for the identification of topological and homological characteristics of distributions in multi-dimensional spaces. We demonstrate here how to apply the toolset of persistent homology to the extraction of novel clustering signatures and the identification of long-range flow correlations in the particle production process of nuclear collisions.

   ↳ nucl-thnucl-exPRC(2022)·6 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.