PaperPanorama
FAQ

Nuclear Theory·nucl-th

Wednesday·December 2, 2020

8 papers—3 primary·5 cross-listed

All8Primary3Cross-lists5
  1. 04

    Single-particle digitization strategy for quantum computation of a scalar field theory

    João Barata🇪🇸 · Niklas Mueller🇺🇸 · Andrey Tarasov🇺🇸 · Raju Venugopalan🇺🇸

    Motivated by the parton picture of high energy quantum chromodynamics, we develop a single-particle digitization strategy for the efficient quantum simulation of relativistic scattering processes in a dimensional scalar field theory. We work out quantum algorithms for initial state preparation, time evolution and final state measurements. We outline a non-perturbative renormalization strategy in this single-particle framework.

    ↳ hep-thhep-phnucl-thquant-phPRA(2021)·85 citations
  2. 05

    Anomalies in Radioactive Decay Rates: A Bibliography of Measurements and Theory

    M. H. McDuffie · P. Graham · J. L. Eppele · J. T. Gruenwald · D. Javorsek II · D. E. Krause · E. Fischbach

    Knowledge of the decay rates (or half-lives) of radioisotopes is critical in many fields, including medicine, archeology, and nuclear physics, to name just a few. Central to the many uses of radioisotopes is the belief that decay rates are fundamental constants of nature, just as the masses of the radioisotopes themselves are. Recently, the belief that decay rates are fundamental constants has been called into question following the observation of various reported anomalies in decay rates, such as apparent periodic variations. The purpose of this bibliography is to collect in one place the relevant literature on both sides of this issue in the expectation that doing so will deepen our understanding of the available data.

    ↳ nucl-exnucl-th9 citations
  3. 06

    Scalar field quasinormal modes of noncommutative high dimensional Schwarzschild-Tangherlini black hole spacetime with smeared matter sources

    Zening Yan🇨🇳 · Chen Wu🇨🇳 · Wenjun Guo🇨🇳

    We investigate the massless scalar quasinormal modes (QNMs) of the noncommutative -dimensional Schwarzschild-Tangherlini black hole spacetime in this paper. By using the Wentzel-Kramers-Brillouin (WKB) approximation method, the asymptotic iterative method (AIM) and the inverted potential method (IPM) method, we made a detail analysis of the massless scalar QNM frequencies by varying the general smeared matter distribution and the allowable characteristic parameters ( and ) corresponding to different dimensions. It is found that the nonconvergence of the high order WKB approximation exists in the QNMs frequencies of scalar perturbation around the noncommutative -dimensional Schwarzschild black holes. We conclude that the 3rd WKB result should be more reliable than those of the high order WKB method since our numerical results are also verified by the AIM method and the IPM method. In the dimensional range of , the scalar QNMs as a function of the different papameters (the noncommutative parameter , the smeared matter distribution parameter , the multipole number and the main node number ) are obtained. Moreover, we study the dynamical evolution of a scalar field in the background of the noncommutative high dimensional Schwarzschild-Tangherlini black hole.

    ↳ gr-qcnucl-thNPB(2020)·21 citations
  4. 07

    Atomic calculations of hyperfine structure anomaly in gold

    Yu. A. Demidov · E. A. Konovalova · R. T. Imanbaeva · M. G. Kozlov · A. E. Barzakh

    The magnetic hyperfine structure constants have been calculated for low-lying levels in neutral gold atom and gold-like ion of mercury taking into account Bohr--Weisskopf (BW) effect. BW effect is represented as a product of atomic and nuclear () factors. We have calculated the atomic factors, which enable one to extract BW-correction values for far from stability gold nuclei from the experimental data. The possible uncertainty of our atomic calculations have been estimated by the comparison with the available experimental data. It has been shown that the standard single-particle approach in calculation reasonably well describes experimental data for gold isomers and ground state of . At the same time, it fails to describe the hyperfine constant in . This indicates the more pronounced configuration mixing in than in .

    ↳ physics.atom-phnucl-thPRA(2021)·6 citations
  5. 08

    Curing the unphysical behaviour of NLO quarkonium production at the LHC and its relevance to constrain the gluon PDF at low scales

    Jean-Philippe Lansberg🇫🇷 · Melih Arslan Ozcelik🇫🇷

    We address the unphysical energy dependence of quarkonium-hadroproduction cross sections at Next-to-Leading Order (NLO) in alpha_S which we attribute to an over-subtraction in the factorisation of the collinear singularities inside the PDFs in the MSbar scheme. Such over- or under-subtractions have a limited phenomenological relevance in most of the scattering processes in particle physics. On the contrary, it is particularly harmful for P_T-integrated charmonium hadroproduction which renders a wide class of NLO results essentially unusable. Indeed, in such processes, alphaS is not so small, the PDFs are not evolved much and can be rather flat for the corresponding momentum fractions and, finally, some process-dependent NLO pieces are either too small or too large. We propose a scale-fixing criterion which avoids such an over-subtraction. We demonstrate its efficiency for eta(c,b) but also for a fictitious light elementary scalar boson. Having provided stable NLO predictions for eta(c,b) P_T-integrated cross sections, sigma^NLO(eta(Q)), and discussed the options to study eta(b) hadroproduction, we argue that their measurement at the LHC can help better determine the gluon PDF at low scales and tell whether the local minimum in conventional NLO gluon PDFs around x=0.001 at scales below 2 GeV is physical or not.

    ↳ hep-phhep-exnucl-exnucl-thEPJC(2021)·34 citations

Affiliations

first authorsco-authorsvia INSPIRE