Nuclear Theory·nucl-th

Tuesday·July 30, 2019

17 papers—9 primary·8 cross-listed

10
Thermodynamic Geometry of the Quark-Meson Model
Bonan Zhang🇨🇳 · Shen-Song Wan🇨🇳 · Marco Ruggieri🇨🇳
We study the thermodynamic geometry of the Quark-Meson model, focusing on the curvature, $R$ , around the chiral crossover at finite temperature and baryon chemical potential. We find a peculiar behavior of $R$ in the crossover region, in which the sign changes and a local maximum develops; in particular, the height of the peak of $R$ in the crossover region becomes large in proximity of the critical endpoint and diverges at the critical endpoint. The appearance of a pronounced peak of $R$ close to the critical endpoint supports the idea that $R$ grows with the correlation volume around the phase transition. We also analyze the mixed fluctuations of energy and baryon number, $⟨ Δ U Δ N ⟩$ , which grow up substantially in proximity of the critical endpoint: in the language of thermodynamic geometry these fluctuations are responsible for the vanishing of the determinant of the metric, which results in thermodynamic instability and are thus related to the appearance of the second order phase transition at the critical endpoint.
↳ hep-phhep-latnucl-thPRD(2020)·12 citations
11
A global extraction of the jet transport coefficient in cold nuclear matter
Peng Ru🇨🇳 · Zhong-Bo Kang🇺🇸 · Enke Wang🇨🇳 · Hongxi Xing🇨🇳 · Ben-Wei Zhang🇨🇳
Within the framework of the generalized QCD factorization formalism, we perform the first global analysis of the jet transport coefficient ( $q^$ ) for cold nuclear matter. The analysis takes into account the world data on transverse momentum broadening in semi-inclusive electron-nucleus deep inelastic scattering, Drell-Yan dilepton and heavy quarkonium production in proton-nucleus collisions, as well as the nuclear modification of the structure functions in deep inelastic scattering, comprising a total of 215 data points from 8 data sets. For the first time, we clarify quantitatively the universality and probing scale dependence of the nuclear medium property as encoded in $q^$ . We expect that the determined parametrization of $q^$ in cold nuclear matter will have significant impact on precise identification of the transport property of hot dense medium created in heavy ion collisions.
↳ hep-phhep-exnucl-exnucl-thPRD(2021)·46 citations
12
Level scheme of $^{153}$ Sm obtained from $^{152}$ Sm( $n_{t h}$ , $γ$ ) reaction using $γ - γ$ coincidence spectrometer
Nguyen Ngoc Anh · Nguyen Quang Hung · Nguyen Xuan Hai · Pham Dinh Khang · A. M. Sukhovoj · L. V. Mitsyna · Ho Huu Thang · Le Hong Khiem
The level scheme of the compound $^{153}$ Sm nucleus formed via the $^{152}$ Sm( $n_{t h}$ , $γ$ ) reaction is studied by using the $γ - γ$ coincidence spectrometer at Dalat Nuclear Research Institute, Vietnam. All the gamma cascades, which correspond to the decays from the compound state to 12 final levels of 0 ( $\frac{3}{2}^{+}$ ), 7.535 ( $\frac{5}{2}^{+}$ ), 35.844 ( $\frac{3}{2}^{-}$ ), 90.875 ( $\frac{5}{2}^{-}$ ), 126.412 ( $\frac{1}{2}^{-}$ ), 127.298 ( $\frac{3}{2}^{-}$ ), 182.902 ( $\frac{5}{2}^{-}$ ), 321.113 ( $\frac{3}{2}^{+}$ ), 404.129 ( $\frac{1}{2}^{-}$ ), 405.470 ( $\frac{3}{2}^{-}$ ), 414.924 ( $\frac{1}{2}^{+}$ ), and 481.088 ( $\frac{3}{2}^{+}$ ) keV, have been measured. A total number of 386 cascades corresponding to 576 gamma transitions has been detected. Among these cascades, 103 primary gamma transitions together with their corresponding intermediate levels and 299 secondary transitions have been determined. In addition, 29 primary gamma transitions, 42 intermediate levels, and 8 secondary transitions have been found to be the same as those extracted from the ENSDF data. The remain 74 primary gamma transitions, 61 intermediate levels, and 291 secondary transitions are therefore considered as the new data. In particular, based on an assumption that most of the transitions are dipole, we have tentatively assigned the unique spin value of $\frac{3}{2} ℏ$ for 53 observed intermediate levels corresponding to the cascades from the compound state to the final ones of 7.535 ( $\frac{5}{2}^{+}$ ), 90.875 ( $\frac{5}{2}^{-}$ ), and 182.902 ( $\frac{5}{2}^{-}$ ) keV, whereas the remain levels are assigned with the spin values in the range of $[\frac{1}{2}, \frac{3}{2}] ℏ$ ...
↳ nucl-exnucl-th0 citations
13
Jet suppression from small to intermediate to large radius
Daniel Pablos🇳🇴
We present predictions for jet suppression from small to intermediate to very large radius, for low and very high energy jets created in heavy ion collisions at the LHC. We use the hybrid strong/weak coupling model for jet quenching that combines perturbative shower evolution with an effective strongly coupled description of the energy and momentum transfer from the jet into the hydrodynamic quark-gluon plasma. Because of momentum conservation, the wake created by the jet enhances or depletes the amount of particles generated at the freeze-out hypersurface depending on their orientation with respect to the jet. Within such framework we find that jet suppression is surprisingly independent of the anti- $k_{T}$ radius $R$ , first slightly increasing as one increases $R$ , then at larger values of $R$ very slowly decreasing. This nearly independence of jet suppression with increasing values of $R$ arises from two competing effects, namely the larger energy loss of the hard jet components, which tends to increase suppression, versus the partial recovery of the lost energy due to medium response, reducing suppression. We also find that the boosted medium from the recoiling jet reduces the amount of plasma in the direction opposite to it in the transverse plane, increasing the amount of jet suppression due to an over-subtraction effect. We show that this characteristic signature of the hydrodynamization of part of the jet energy can be quantified by selecting samples of dijet configurations with different relative pseudorapidities between the leading and the subleading jet.
↳ hep-phnucl-thPRL(2020)·67 citations
14
Chiral susceptibility in Nambu Jona Lasinio model: a Wigner function approach
Arpan Das🇮🇳 · Deepak Kumar🇮🇳 · Hiranmaya Mishra🇮🇳
We estimate here chiral susceptibility at finite temperature within the framework of the Nambu-Jona-Lasinio model (NJL) using the Wigner function approach. We also estimate it in the presence of chiral chemical potential ( $μ_{5}$ ) as well as a non vanishing magnetic field ( $B$ ). We use medium separation regularization scheme (MSS) to calculate the chiral condensate and corresponding susceptibility. It is observed that for a fixed value of chiral chemical potential ( $μ_{5}$ ), transition temperature increases with the magnetic field. While for the fixed value of the magnetic field, transition temperature decreases with chiral chemical potential. For a strong magnetic field, we observe non degeneracy in susceptibility for up and down type quarks.
↳ hep-phnucl-thPRD(2019)·19 citations
15
New physics from COHERENT data with improved Quenching Factor
Amir N. Khan🇩🇪 · Werner Rodejohann🇩🇪
A recent new measurement and re-analysis of past measurements suggested an improved quenching factor value and uncertainty for CsI[Na]. This implies a measurement of the COHERENT experiment of coherent elastic neutrino-nucleus scattering that is closer to the Standard Model prediction and has less uncertainty. We illustrate the impact of this improvement by revisiting fits to the Weinberg angle, neutrino magnetic moments, neutron rms and neutrino charge radii, neutrino non-standard interactions (in particular those relevant for LMA-Dark) and new scalar as well as vector bosons. Significant improvement is observed, particularly for those scenarios coherently affecting the electroweak SM process.
↳ hep-phastro-ph.HEhep-exnucl-thPRD(2019)·75 citations
16
Theory of strongly paired fermions with arbitrary short-range interactions
Jianshen Hu · Fan Wu · Lianyi He · Xia-Ji Liu · Hui Hu
We develop an effective field theory to describe the superfluid pairing in strongly interacting fermions with arbitrary short-range attractions, by extending Kaplan's idea of coupling fermions to a fictitious boson state in Nucl. Phys. B \textbf{494}, 471 (1997). This boson field is assigned with unconventional kinetic term to recover the exact scattering phase shift obtained either from scattering data or model calculations. The theory works even if the explicit form of the interaction potential has not been constructed from scattering data. The contact boson-fermion coupling allows us to go beyond mean-field to include Gaussian pair fluctuations, yielding reliable predictions on equations of state. As an application, we use our theory to address the non-univerisal ground-state energy of strongly paired fermions, due to the non-trivial momentum dependence of the phase shift characterized, for example, by effective range. We find a good agreement between our predictions and recent quantum Monte Carlo simulations on the effective-range dependence in both three and two spatial dimensions. We propose that in cold-atom experiments, the non-universal dependence in thermodynamics can be probed using dark-state optical control of Feshbach resonances.
↳ cond-mat.quant-gascond-mat.supr-connucl-thPRA(2020)·8 citations
17
Can We Observe Jet $P_{T}$ -broadening in Heavy-Ion Collisions at the LHC?
Felix Ringer🇺🇸 · Bo-Wen Xiao🇨🇳 · Feng Yuan🇺🇸
We investigate the effect of PT-broadening on jet substructure observables in heavy-ion collisions at the LHC. As an example, we focus on the opening angle of the two branches that satisfy the soft drop grooming condition in a highly energetic jet. The medium modification of the angular distribution can provide important information on the jet transport properties of hot QCD matter. In addition, we take into account a change of the overall fraction of quark and gluon jets in heavy-ion collisions. We comment on the comparison to a recent measurement from the ALICE Collaboration.
↳ hep-phnucl-exnucl-thPLB(2020)·58 citations

Affiliations

first authorsco-authorsvia INSPIRE