Nuclear Theory·nucl-th

Monday·March 21, 2022

9 papers—5 primary·4 cross-listed

06
Next-to-leading order scalar contributions to $μ \to e$ conversion
Vincenzo Cirigliano🇺🇸 · Kaori Fuyuto🇺🇸 · Michael J. Ramsey-Musolf🇨🇳 · Evan Rule🇺🇸
Within a class of models in which lepton flavor violation is induced dominantly by scalar particle exchanges, we estimate the $μ \to e$ conversion rate in several nuclei. We include next-to-leading order (NLO) terms in the one- and two-nucleon interactions in chiral effective theory, rectifying some incorrect results in the previous literature. We provide an uncertainty budget for the conversion rates and we find that NLO contributions affect the amplitudes at the level of $10%$ , which could be larger than the uncertainty on the leading order couplings, dominated by the strange and non-strange nucleon sigma terms. We study the implications of our results for testing Higgs-mediated CLFV in the future by combining results from various experimental searches, such as $μ \to e$ conversion in multiple target nuclei and $μ \to e γ$ .
↳ hep-phnucl-thPRC(2022)·27 citations
07
Prediction of five-flavored pentaquarks
Chao-Wei Shen🇩🇪 · Ulf-G. Meißner🇩🇪
We analyze the possibility of the existence of a fully exotic pentaquark state $u d sc b ˉ$ , which is made from the five different flavors participarting in the strong interactions. We investigate the coupled channel effects of the $B^{(*)} Ξ_{c} - B^{(*)} Ξ_{c}^{'}$ system through $t$ -channel vector meson exchange to search for such states. A $B Ξ_{c}$ and a $B Ξ_{c}^{'}$ bound state are found to have binding energies of about $10 - 30$ ~MeV with $B_{s} Λ_{c}$ and $B_{c} Λ$ being the possible decay channels. Similarly, a bound state is formed in the $B^{*} Ξ_{c}$ and $B^{*} Ξ_{c}^{'}$ channels, respectively. These states could be searched for through the $pp \to B_{c} Λ X$ or $pp \to B_{s}^{(*)} Λ_{c} X$ processes by the LHCb collaboration.
↳ hep-phhep-exnucl-thPLB(2022)·10 citations
08
Electron removal energies in noble gas atoms up to 100 keV: ab initio GW vs XPS
Iskander Mukatayev🇫🇷 · Benoît Sklénard🇫🇷 · Valerio Olevano🇫🇷 · Jing Li🇫🇷
X-ray photoelectron spectroscopy (XPS) measures electron removal energies, providing direct access to core and valence electron binding energies, hence probing the electronic structure. In this work, we benchmark for the first time the ab initio many-body GW approximation on the complete electron binding energies of noble gas atoms (He-Rn), which spans 100~keV. Our results demonstrate that GW achieves an accuracy within 1.2% in XPS binding energies, by systematically restoring the underestimation from density-functional theory (DFT, error of 14%) or the overestimation from Hartree-Fock (HF, error of 4.7%). Such results also imply the correlations of $d$ electrons are very well described by GW.
↳ cond-mat.othercond-mat.str-elnucl-thphysics.atom-ph+1PRB(2022)·0 citations
09
Scaling properties of background- and chiral-magnetically-driven charge separation in heavy ion collisions at $s_{NN} = 200$ GeV
Roy A. Lacey (1) · Niseem Magdy (2) · Petr Parfenov (3) · Arkadiy Taranenko (3) ((1) Depts. of Chemistry and Physics, Stony Brook University, Stony Brook, New York, USA (2) Department of Physics, University of Illinois at Chicago, Chicago, Illinois, USA (3) National Research Nuclear University MEPhI, Moscow, Russia)
The Anomalous Viscous Fluid Dynamics model, AVFD, is used in concert with the charge-sensitive correlator $R_{Ψ_{2}} (Δ S)$ to investigate the scaling properties of background- and chiral-magnetically-driven (CME) charge separation ( $Δ S$ ), characterized by the inverse variance $σ_{R_{Ψ_{2}}}^{- 2}$ of the $R_{Ψ_{2}} (Δ S)$ distributions obtained in collisions at $s_{NN} = 200$ GeV. The $σ_{R_{Ψ_{2}}}^{- 2}$ values for the background are observed to be event-shape-independent. However, they scale with the reciprocal charged-particle multiplicity $(1/ ⟨ N_{ch} ⟩)$ , indicating an essential constraint for discerning background from the signal and a robust estimate of the difference between the backgrounds in Ru+Ru and Zr+Zr collisions. By contrast, the $σ_{R_{Ψ_{2}}}^{- 2}$ values for signal + background show characteristic $1/ ⟨ N_{ch} ⟩$ scaling violations that characterize the CME-driven contributions. Corrections to recent $R_{Ψ_{2}} (Δ S)$ measurements \cite{STAR:2021mii} that account for the background difference in Ru+Ru and Zr+Zr collisions indicate a charge separation difference compatible with the CME. The results further suggest that $σ_{R_{Ψ_{2}}}^{- 2}$ measurements for peripheral and central collisions in concert with $1/ ⟨ N_{ch} ⟩$ scaling, provides a robust constraint to quantify the background and aid characterization of the CME.
↳ nucl-exhep-exhep-phnucl-th6 citations

Affiliations

first authorsco-authorsvia INSPIRE

Next-to-leading order scalar contributions to μ→e conversion

Prediction of five-flavored pentaquarks

Electron removal energies in noble gas atoms up to 100 keV: ab initio GW vs XPS

Scaling properties of background- and chiral-magnetically-driven charge separation in heavy ion collisions at s​NN​=200 GeV

Affiliations

Next-to-leading order scalar contributions to $μ \to e$ conversion

Scaling properties of background- and chiral-magnetically-driven charge separation in heavy ion collisions at $s_{NN} = 200$ GeV