The absence of observed charmonium-like states with the exotic quantum numbers <math altimg='si1.svg'><msup><mrow><mi>J</mi></mrow><mrow><mi>P</mi><mi>C</mi></mrow></msup><mo linebreak='goodbreak' linebreakstyle='after'>=</mo><msup><mrow><mn>1</mn></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>&#8722;</mo><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup></math> has prompted us to investigate the production rates of the <math altimg='si2.svg'><msup><mrow><mn>1</mn></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>&#8722;</mo><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup></math> <math altimg='si3.svg'><mi>D</mi><mspace width='0.2em' /><msub><mrow><mover accent='true'><mrow><mi>D</mi></mrow><mo>&#8254;</mo></mover></mrow><mrow><mn>1</mn></mrow></msub><mo stretchy='false'>(</mo><mn>2420</mn><mo stretchy='false'>)</mo></math> and <math altimg='si4.svg'><msup><mrow><mi>D</mi></mrow><mrow><mo>&#8270;</mo></mrow></msup><mspace width='0.2em' /><msub><mrow><mover accent='true'><mrow><mi>D</mi></mrow><mo>&#8254;</mo></mover></mrow><mrow><mn>1</mn></mrow></msub><mo stretchy='false'>(</mo><mn>2420</mn><mo stretchy='false'>)</mo></math> hadronic molecules, which we refer to as <math altimg='si131.svg'><msub><mrow><mi>&#951;</mi></mrow><mrow><mi>c</mi><mn>1</mn></mrow></msub></math> and <math altimg='si128.svg'><msubsup><mrow><mi>&#951;</mi></mrow><mrow><mi>c</mi><mn>1</mn></mrow><mrow><mo>&#8242;</mo></mrow></msubsup></math>, respectively, in electron-positron collisions. Assuming a hadronic molecular nature for the vector charmonium-like states <math altimg='si7.svg'><mi>&#968;</mi><mo stretchy='false'>(</mo><mn>4360</mn><mo stretchy='false'>)</mo></math> and <math altimg='si8.svg'><mi>&#968;</mi><mo stretchy='false'>(</mo><mn>4415</mn><mo stretchy='false'>)</mo></math>, we evaluate the radiative decay widths of <math altimg='si9.svg'><mi>&#968;</mi><mo stretchy='false'>(</mo><mn>4360</mn><mo stretchy='false'>)</mo><mo stretchy='false'>&#8594;</mo><mi>&#947;</mi><msub><mrow><mi>&#951;</mi></mrow><mrow><mi>c</mi><mn>1</mn></mrow></msub></math> and <math altimg='si10.svg'><mi>&#968;</mi><mo stretchy='false'>(</mo><mn>4415</mn><mo stretchy='false'>)</mo><mo stretchy='false'>&#8594;</mo><mi>&#947;</mi><msubsup><mrow><mi>&#951;</mi></mrow><mrow><mi>c</mi><mn>1</mn></mrow><mrow><mo>&#8242;</mo></mrow></msubsup></math>. Using these decay widths, we estimate the cross sections for producing <math altimg='si131.svg'><msub><mrow><mi>&#951;</mi></mrow><mrow><mi>c</mi><mn>1</mn></mrow></msub></math> and <math altimg='si128.svg'><msubsup><mrow><mi>&#951;</mi></mrow><mrow><mi>c</mi><mn>1</mn></mrow><mrow><mo>&#8242;</mo></mrow></msubsup></math> in electron-positron annihilations, as well as the event numbers at the planned Super <italic>&#964;</italic>-Charm Facility. Our results suggest that the ideal energy region for observing these states is around 4.44 and 4.50 GeV, just above the <math altimg='si4.svg'><msup><mrow><mi>D</mi></mrow><mrow><mo>&#8270;</mo></mrow></msup><mspace width='0.2em' /><msub><mrow><mover accent='true'><mrow><mi>D</mi></mrow><mo>&#8254;</mo></mover></mrow><mrow><mn>1</mn></mrow></msub><mo stretchy='false'>(</mo><mn>2420</mn><mo stretchy='false'>)</mo></math> and <math altimg='si11.svg'><msup><mrow><mi>D</mi></mrow><mrow><mo>&#8270;</mo></mrow></msup><mspace width='0.2em' /><msubsup><mrow><mover accent='true'><mrow><mi>D</mi></mrow><mo>&#8254;</mo></mover></mrow><mrow><mn>2</mn></mrow><mrow><mo>&#8270;</mo></mrow></msubsup><mo stretchy='false'>(</mo><mn>2460</mn><mo stretchy='false'>)</mo></math> thresholds, respectively.

China

Xiao-Yu Zhang

Spain

Pan-Pan Shi

Feng-Kun Guo

Production of 1 <sup>&#8722;+</sup> exotic charmonium-like states in electron-positron collisions

We study the transverse momentum ( $p_T$ ) differential anisotropic flow and flow fluctuation in Pb+Pb collisions at $\sqrt{s_{_{NN}}}$ =5.02 TeV at the LHC. A (3+1)-dimensional CLVisc hydrodynamics framework with fluctuating TRENTO (or AMPT) initial conditions is utilized to simulate the space-time evolution of the quark-gluon plasma (QGP) medium. The effects of shear viscosity and the sub-nucleon structure on anisotropic flow and flow fluctuation are analyzed. Our result shows that shear viscosity tends to suppress both flow coefficients ( ${v_2\{2}\}$ , ${v_2\{4\}}$ , and ${\langle v_2\rangle}$ ) and flow fluctuation ( ${\sigma_{v_2}}$ ) owing to its smearing effect on local density fluctuation. The flow coefficients appear to be insensitive to the sub-nucleon structure, whereas the flow fluctuation ${\sigma_{v_2}}$ tends to be suppressed by the sub-nucleon structure in central collisions but enhanced in peripheral collisions. After taking into account the sub-nucleon structure effect, our numerical result can qualitatively describe the relative flow fluctuations ( ${v_2\{4\}/v_2\{2\}}$ , $F({v_2})$ ) measured by the ALICE Collaboration at the LHC. We further investigate the effects of shear viscosity, sub-nucleon structure, and initial condition model on the flow angle and flow magnitude decorrelations ( ${A_2^f}$ , ${M_2^f}$ ) using the four-particle correlation method. We find that the flow decorrelation effect is typically stronger in central collisions than in peripheral collisions. The flow angle decorrelation is found to be insensitive to the shear viscosity and sub-nucleon structure, whereas the flow magnitude decorrelation shows quite different behaviors when using the TRENTO and AMPT initial condition models. Our study sheds light on the anisotropic flow, transport properties, and initial structure of the QGP created in high-energy nuclear collisions.

Germany

Jie Zhu

Canada

Xiang-Yu Wu

Guang-You Qin

Anisotropic flow, flow fluctuation, and flow decorrelation in relativistic heavy-ion collisions: the roles of sub-nucleon structure and shear viscosity * Supported in part by the Natural Science Foundation of China (12225503, 11890710, 11890711, 11935007). Zhu Jie is supported in part by the China Scholarship Council (202306770009). Wu Xiang-Yu is supported in part by the National Science Foundation within the framework of the JETSCAPE collaboration (OAC-2004571) and in part by the Natural Sciences and Engineering Research Council of Canada. Some of the calculations were performed in the Nuclear Science Computing Center at Central China Normal University (NSC$^{3}$), Wuhan, Hubei, China.

In this paper, we construct the Dirac stars model composed of two Dirac fields and Einstein gravity in four-dimensional Anti-de Sitter spacetime. We consider the Dirac stars with free field (no self-interacting). Our investigation focuses on understanding the relationship between Arnowitt–Deser–Misner (ADM) mass and binding energy in relation to the cosmological constant. Furthermore, we extend the study to the Dirac stars with self-interacting potentials. For the self-interacting Dirac stars, three types of interactions are examined: only quartic, only sextic, quartic and sextic interactions that is kind of Q-ball type interactions. In these three distinct scenarios, it is essential to investigate the impact of self-interaction constants on Dirac stars. Additionally, we study the Dirac solitons in the AdS background. Finally, we discussed the dependence of the spectral flow of the Dirac Hamiltonian on the model parameters.

Li Zhao

Yong-Qiang Wang

Dirac stars in Anti-de Sitter spacetime

We use the spectral lag catalog of 46 short GRBs aggregated by Xiao et al. (Astrophys J Lett 924:L29, 2022), to carry out an independent search for Lorentz invariance violation (LIV). For this purpose, we use a power-law model as a function of energy for the intrinsic astrophysical induced spectral lags. The expansion history of the universe needed for constraining LIV was obtained in a non-parametric method using cosmic chronometers. We use Bayesian model comparison to determine if the aforementioned spectral lags show evidence for LIV as compared to only astrophysically induced lags. We do not find any evidence for LIV, and obtain 95% CL lower limits on the corresponding energy scale to be  $$4 \times 10^{15}$$  <math> <mrow> <mn>4</mn> <mo>×</mo> <msup> <mn>10</mn> <mn>15</mn> </msup> </mrow> </math>   GeV and  $$6.8 \times 10^{9}$$  <math> <mrow> <mn>6.8</mn> <mo>×</mo> <msup> <mn>10</mn> <mn>9</mn> </msup> </mrow> </math>   GeV for the linear and quadratic LIV models respectively. Our results obtained by using the flat  $$\Lambda $$  <math> <mi>Λ</mi> </math>  CDM model for characterizing the cosmic expansion history are consistent with those obtained using chronometers.

India

Shantanu Desai

Rajdeep Agrawal

Haveesh Singirikonda

Search for Lorentz invariance violation using Bayesian model comparison applied to Xiao et al. GRB spectral lag catalog

Using the vector exchange interaction in the local hidden gauge approach, which in the light quark sector generates the chiral Lagrangians and has produced realistic results for 
					 and the hidden charm pentaquark states, we study the meson-baryon interactions in the coupled channels that lead to the 
					 and 
					 excited states of the molecular type. We obtain seven states of the 
					 type with energies between 
					 and 
					 MeV, and one 
					 state at 
					 MeV.
				

Brazil

J. M. Dias

Qi-Xin Yu

Wei-Hong Liang

Zhi-Feng Sun

Ju-Jun Xie

E. Oset

Ξbb and Ωbbb molecular states Partly supported by the National Natural Science Foundation of China (11975083, 11947413, 11847317, 11565007, 11735003, 1191101015). Q. X Yu acknowledges the support from the National Natural Science Foundation of China (11775024, 11575023, 11805153) and China Scholarship Council. Partly supported by the Spanish Ministerio de Economia y Competitividad and European FEDER funds (FIS2017- 84038-C2-1-P B, FIS2017-84038-C2-2-P B), and the Generalitat Valenciana in the program Prometeo II-2014/068, and the project Severo Ochoa of IFIC, SEV-2014-0398

We present a systematic short time expansion for the generating function of the one point height probability distribution for the KPZ equation with droplet initial condition, which goes much beyond previous studies. The expansion is checked against a numerical evaluation of the known exact Fredholm determinant expression. We also obtain the next order term for the Brownian initial condition. Although initially devised for short time, a resummation of the series allows to obtain also the long time large deviation function, found to agree with previous works using completely different techniques. Unexpected similarities with stationary large deviations of TASEP with periodic and open boundaries are discussed. Two additional applications are given. (i) Our method is generalized to study the linear statistics of the Airy point process, i.e. of the GUE edge eigenvalues. We obtain the generating function of the cumulants of the empirical measure to a high order. The second cumulant is found to match the result in the bulk obtained from the Gaussian free field by Borodin and Ferrari [1,2], but we obtain systematic corrections to the Gaussian free field (higher cumulants, expansion towards the edge). This also extends a result of Basor and Widom [3] to a much higher order. We obtain large deviation functions for the Airy point process for a variety of linear statistics test functions. (ii) We obtain results for the counting statistics of trapped fermions at the edge of the Fermi gas in both the high and the low temperature limits.

France

Alexandre Krajenbrink

Pierre Le Doussal

Sylvain Prolhac

Systematic time expansion for the Kardar–Parisi–Zhang equation, linear statistics of the GUE at the edge and trapped fermions

We improve the Monte-Carlo based QCD sum rules by introducing the rigorous Hölder-inequality-determined sum rule window and a Breit-Wigner type parametrization for the phenomenological spectral function. In this improved sum rule analysis methodology, the sum rule analysis window can be determined without any assumptions on OPE convergence or the QCD continuum. Therefore, an unbiased prediction can be obtained for the phenomenological parameters (the hadronic mass and width etc.). We test the new approach in the ρ meson channel with re-examination and inclusion of αs corrections to dimension-4 condensates in the OPE. We obtain results highly consistent with experimental values. We also discuss the possible extension of this method to some other channels.

Qi-Nan Wang

Zhu-Feng Zhang

T.G. Steele

Hong-Ying Jin

Zhuo-Ran Huang

A comprehensive revisit of the ρ meson with improved Monte-Carlo based QCD sum rulesSupported by NSFC (11175153, 11205093, 11347020), Open Foundation of the Most Important Subjects of Zhejiang Province, and K. C. Wong Magna Fund in Ningbo University, TGS is Supported by the Natural Sciences and Engineering Research Council of Canada (NSERC), Z. F. Zhang and Z. R. Huang are Grateful to the University of Saskatchewan for its Warm Hospitality

None Supervisory Editors of Nuclear Physics B

Editorial note on “Lepton-flavor violation and (g−2)μ in the μν SSM” by Hai-Bin Zhang, Tai-Fu Feng, Shu-Min Zhao and Tie-Jun Gao [Nucl. Phys. B 873 (2) (2013) 300–324]