Thu·Mar 2, 2023Thursday·March 2, 2023

1. 01*

   Quantum Information Science and Technology for Nuclear Physics. Input into U.S. Long-Range Planning, 2023

   Douglas Beck🇺🇸 · Joseph Carlson🇺🇸 · Zohreh Davoudi🇺🇸 · Joseph Formaggio🇺🇸 · Sofia Quaglioni🇺🇸 · Martin Savage🇺🇸 · Joao Barata🇺🇸 · Tanmoy Bhattacharya🇺🇸 · Michael Bishof🇺🇸 · Ian Cloet🇺🇸 · Andrea Delgado🇺🇸 · Michael DeMarco🇺🇸 and 89 other authors

   In preparation for the 2023 NSAC Long Range Plan (LRP), members of the Nuclear Science community gathered to discuss the current state of, and plans for further leveraging opportunities in, QIST in NP research at the Quantum Information Science for U.S. Nuclear Physics Long Range Planning workshop, held in Santa Fe, New Mexico on January 31 - February 1, 2023. The workshop included 45 in-person participants and 53 remote attendees. The outcome of the workshop identified strategic plans and requirements for the next 5-10 years to advance quantum sensing and quantum simulations within NP, and to develop a diverse quantum-ready workforce. The plans include resolutions endorsed by the participants to address the compelling scientific opportunities at the intersections of NP and QIST. These endorsements are aligned with similar affirmations by the LRP Computational Nuclear Physics and AI/ML Workshop, the Nuclear Structure, Reactions, and Astrophysics LRP Town Hall, and the Fundamental Symmetries, Neutrons, and Neutrinos LRP Town Hall communities.

   nucl-exnucl-thquant-ph68 citations
2. 02*

   The total neutron production from the alpha induced reaction on natural Zirconium

   Vafiya Thaslim T T · M M Musthafa · Midhun C V · S. Ghugre🇮🇳 · Gokul Das H · Swapna B · Najmunnisa T · F S Shana · Rijin N T · S Dasgupta🇮🇳 · J Datta

   A significant amount of alpha particles, upto $\sim$ 35 MeV are produced in the reactor environment. Alpha induced reaction on natural Zirconium, a reactor component, upto 40 MeV has been measured using stacked foil activation technique. The total neutron production cross section from all possible channels for $\alpha$ energies upto 35 MeV is also estimated using TALYS 1.96. The isomeric cross section ratio for the production of the radionuclide ${}^{95}Nb$ has been measured and reported for the first time.

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

   Coexistence of single particle and collective excitation in ${}^{61}$Ni

   Soumik Bhattacharya🇮🇳 · Vandana Tripathi🇮🇳 · E. Rubino🇺🇸 · Samuel Ajayi🇺🇸 · L. T. Baby🇺🇸 · C. Benetti · R. S. Lubna🇺🇸 · S. L. Tabor · J. Döring · Y. Utsuno🇯🇵 · N. Shimizu🇯🇵 · J. M. Almond · G. Mukherjee🇮🇳

   The high spin states in 61 Ni have been studied using the fusion evaporation reaction, Ti( ${}^{14}$C,3n) ${}^{61}$Ni at an incident beam energy of 40 MeV. A Compton suppressed multi-HPGe detector setup, consisting of six Clover detectors and three single crystal HPGe detectors was used to detect the de-exciting $\gamma$ rays from the excited states. The level scheme has been extended up to an excitation energy of 12.8 MeV and a tentative J${}_{\pi }$ = 35/2${}^{+}$ . The low-lying negative parity levels are found to be generated by single particle excitation within the f p shell and also excitations to the g${}_{9/2}$ orbitals as explained well with shell model calculations using the GXPF1Br+V M U (modified) interaction. Two rotational structure of regular E2 sequences with small to moderate axial deformation have been established at higher excitation energy. Most interestingly, two sequences of M1 transitions are reported for the first time and described as magnetic rotational bands. The shears mechanism for both the bands can be described satisfactorily by the geometrical model. The shell model calculation involving the cross shell excitation beyond the fp shell well reproduce the M1 and E2 sequences. The shell model predicted B(M1) values for the magnetic rotational band B1 show the decreasing trend with spin as expected with closing of the shears.

   nucl-exnucl-thPRC(2023)·10 citations
4. 04*

   Inclusive photon production at forward rapidities in pp and p$-$Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV

   ALICE Collaboration

   A study of multiplicity and pseudorapidity distributions of inclusive photons measured in pp and p$-$Pb collisions at a center-of-mass energy per nucleon$-$nucleon collision of $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV using the ALICE detector in the forward pseudorapidity region $2.3<{\eta }_{\mathrm{lab}}<3.9$ is presented. Measurements in p$-$Pb collisions are reported for two beam configurations in which the directions of the proton and lead ion beam were reversed. The pseudorapidity distributions in p$-$Pb collisions are obtained for seven centrality classes which are defined based on different event activity estimators, i.e., the charged-particle multiplicity measured at midrapidity as well as the energy deposited in a calorimeter at beam rapidity. The inclusive photon multiplicity distributions for both pp and p$-$Pb collisions are described by double negative binomial distributions. The pseudorapidity distributions of inclusive photons are compared to those of charged particles at midrapidity in \pp collisions and for different centrality classes in p$-$Pb collisions. The results are compared to predictions from various Monte Carlo event generators. None of the generators considered in this paper reproduces the inclusive photon multiplicity distributions in the reported multiplicity range. The pseudorapidity distributions are, however, better described by the same generators.

   nucl-exhep-exEPJC(2023)·7 citations
5. 05*

   Azimuthal correlations of heavy-flavor hadron decay electrons with charged particles in pp and p-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV

   ALICE Collaboration

   The azimuthal ($\Delta \phi$) correlation distributions between heavy-flavor decay electrons and associated charged particles are measured in pp and p$-$Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV. Results are reported for electrons with transverse momentum $4<p_{\mathrm{T}}<16$ GeV/$c$ and pseudorapidity $|\eta |<0.6$. The associated charged particles are selected with transverse momentum $1<p_{\mathrm{T}}<7$ GeV/$c$, and relative pseudorapidity separation with the leading electron $|\Delta \eta |<1$. The correlation measurements are performed to study and characterize the fragmentation and hadronization of heavy quarks. The correlation structures are fitted with a constant and two von Mises functions to obtain the baseline and the near- and away-side peaks, respectively. The results from p$-$Pb collisions are compared with those from pp collisions to study the effects of cold nuclear matter. In the measured trigger electron and associated particle kinematic regions, the two collision systems give consistent results. The $\Delta \phi$ distribution and the peak observables in pp and p$-$Pb collisions are compared with calculations from various Monte Carlo event generators.

   nucl-exhep-exEPJC(2023)·14 citations
6. 06*

   Measurement of the radius dependence of charged-particle jet suppression in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV

   ALICE Collaboration

   The ALICE Collaboration reports a differential measurement of inclusive jet suppression using pp and Pb$-$Pb collision data at a center-of-mass energy per nucleon-nucleon collision $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV. Charged-particle jets are reconstructed using the anti-$k_{\mathrm{T}}$ algorithm with resolution parameters $R=$ 0.2, 0.3, 0.4, 0.5, and 0.6 in pp collisions and $R=$ 0.2, 0.4, 0.6 in central (0$-$10%), semi-central (30$-$50%), and peripheral (60$-$80%) Pb$-$Pb collisions. A novel approach based on machine learning is employed to mitigate the influence of jet background. This enables measurements of inclusive jet suppression in new regions of phase space, including down to the lowest jet $p_{\mathrm{T}}\ge 40$ GeV/$c$ at $R=0.6$ in central Pb$-$Pb collisions. This is an important step for discriminating different models of jet quenching in the quark-gluon plasma. The transverse momentum spectra, nuclear modification factors, derived cross section, and nuclear modification factor ratios for different jet resolution parameters of charged-particle jets are presented and compared to model predictions. A mild dependence of the nuclear modification factor ratios on collision centrality and resolution parameter is observed. The results are compared to a variety of jet-quenching models with varying levels of agreement.

   nucl-exhep-exPLB(2024)·79 citations
7. 07*

   Measurement of the $\Lambda$ hyperon lifetime

   ALICE Collaboration

   A new, more precise measurement of the $\Lambda$ hyperon lifetime is performed using a large data sample of Pb$-$Pb collisions at $\sqrt{s_{\mathrm{NN}}}=5.02$ TeV with ALICE. The $\Lambda$ and $\overline{\Lambda }$ hyperons are reconstructed at midrapidity using their two-body weak decay channel $\Lambda \to \mathrm{p}+{\pi }^{-}$ and $\overline{\Lambda }\to \overline{\mathrm{p}}+{\pi }^{+}$. The measured value of the $\Lambda$ lifetime is ${\tau }_{\Lambda }=[261.07\pm 0.37(stat.)\pm 0.72(syst.)]\mathrm{ps}$. The relative difference between the lifetime of $\Lambda$ and $\overline{\Lambda }$, which represents an important test of CPT invariance in the strangeness sector, is also measured. The obtained value $({\tau }_{\Lambda }-{\tau }_{\overline{\Lambda }})/{\tau }_{\Lambda }=0.0013\pm 0.0028(stat.)\pm 0.0021(syst.)$ is consistent with zero within the uncertainties. Both measurements of the $\Lambda$ hyperon lifetime and of the relative difference between ${\tau }_{\Lambda }$ and ${\tau }_{\overline{\Lambda }}$ are in agreement with the corresponding world averages of the Particle Data Group and about a factor of three more precise.

   nucl-exhep-exPRD(2023)·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.