The Gamow shell model (GSM) framework is extended to the study of weakly bound hypernuclei. As an initial application, we investigate the neutron-rich He hyper-isotopes from <math altimg='si1.svg'><msubsup><mrow /><mrow><mi mathvariant='normal'>&#923;</mi></mrow><mrow><mn>6</mn></mrow></msubsup></math>He to <math altimg='si2.svg'><msubsup><mrow /><mrow><mi mathvariant='normal'>&#923;</mi></mrow><mrow><mn>9</mn></mrow></msubsup></math>He, accurately treating the unbound or loosely bound character of hypernuclear many-body states. The energy spectra, calculated using a phenomenological Hamiltonian with an effective <italic>YN</italic> interaction, show good agreement with available experimental data. In particular, neutron-emitting resonant states are predicted for the neutron-rich nuclei 5&#8722;8He and the hypernucleus <math altimg='si1.svg'><msubsup><mrow /><mrow><mi mathvariant='normal'>&#923;</mi></mrow><mrow><mn>6</mn></mrow></msubsup></math>He. Furthermore, neutron densities exhibit the long-range character of weakly bound and resonant states. This study demonstrates that GSM is a practical tool for describing the complex structure of hypernuclei, especially for those close to drip lines.

China

Xin Li

Nicolas Michel

Jianguo Li

Xian-Rong Zhou

Gamow shell model description of neutron-rich He hyper-isotopes

We investigate Λ production in the ( <math altimg='si146.svg'><msup><mrow><mi>&#960;</mi></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup></math>, <math altimg='si3.svg'><msup><mrow><mi>K</mi></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup></math>) reaction on a 6Li target at <math altimg='si4.svg'><msub><mrow><mi>p</mi></mrow><mrow><msup><mrow><mi>&#960;</mi></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup></mrow></msub><mo linebreak='goodbreak' linebreakstyle='after'>=</mo><mn>1.05</mn></math> GeV/ <italic>c</italic>, using the distorted-wave impulse approximation (DWIA) with the Fermi-averaged <math altimg='si5.svg'><msup><mrow><mi>&#960;</mi></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup><mi>n</mi><mo stretchy='false'>&#8594;</mo><msup><mrow><mi>K</mi></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup><mi mathvariant='normal'>&#923;</mi></math> amplitudes. The calculated spectrum is in good agreement with the experimental data, suggesting that <math altimg='si1.svg'><mmultiscripts><mrow><mi mathvariant='normal'>He</mi></mrow><mprescripts /><mrow><mi mathvariant='normal'>&#923;</mi></mrow><mrow><mn>4</mn></mrow></mmultiscripts></math>- <italic>d</italic> configurations play a key role in describing the &#923; continuum states of <math altimg='si23.svg'><msubsup><mrow /><mrow><mi mathvariant='normal'>&#923;</mi></mrow><mrow><mn>6</mn></mrow></msubsup></math>Li near and above the <math altimg='si8.svg'><mmultiscripts><mrow><mi mathvariant='normal'>He</mi></mrow><mprescripts /><none /><mrow><mn>3</mn></mrow></mmultiscripts><mo linebreak='goodbreak' linebreakstyle='after'>+</mo><mi>d</mi><mo linebreak='goodbreak' linebreakstyle='after'>+</mo><mi mathvariant='normal'>&#923;</mi></math> threshold. Our analysis shows that the <math altimg='si1.svg'><mmultiscripts><mrow><mi mathvariant='normal'>He</mi></mrow><mprescripts /><mrow><mi mathvariant='normal'>&#923;</mi></mrow><mrow><mn>4</mn></mrow></mmultiscripts></math> hypernucleus as a hyperfragment is prominently produced through <italic>D</italic>-wave resonances with <math altimg='si9.svg'><msup><mrow><mi>J</mi></mrow><mrow><mi>P</mi></mrow></msup><mo linebreak='goodbreak' linebreakstyle='after'>=</mo><msup><mrow><mn>3</mn></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup></math>, <math altimg='si10.svg'><msup><mrow><mn>2</mn></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup></math>, and <math altimg='si11.svg'><msup><mrow><mn>1</mn></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup></math> in the <math altimg='si108.svg'><mmultiscripts><mrow><mi mathvariant='normal'>He</mi></mrow><mprescripts /><mrow><mi mathvariant='normal'>&#923;</mi></mrow><mrow><mn>4</mn></mrow></mmultiscripts><mo linebreak='goodbreak' linebreakstyle='after'>+</mo><mi>d</mi></math> channel at a large momentum transfer <math altimg='si13.svg'><mi>q</mi><mo>&#8771;</mo><mn>360</mn></math>&#8211;400 MeV/ <italic>c</italic>. These findings provide theoretical evidence for the production of a <math altimg='si1.svg'><mmultiscripts><mrow><mi mathvariant='normal'>He</mi></mrow><mprescripts /><mrow><mi mathvariant='normal'>&#923;</mi></mrow><mrow><mn>4</mn></mrow></mmultiscripts></math> hyperfragment via a cluster-like mechanism in the 6Li( <math altimg='si146.svg'><msup><mrow><mi>&#960;</mi></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup></math>, <math altimg='si3.svg'><msup><mrow><mi>K</mi></mrow><mrow><mo linebreak='badbreak' linebreakstyle='after'>+</mo></mrow></msup></math>) reaction.

Japan

Toru Harada

Yoshiharu Hirabayashi

Evidence for <math altimg='si1.svg'><mmultiscripts><mrow><mi mathvariant='normal'>He</mi></mrow><mprescripts /><mrow><mi mathvariant='normal'>&#923;</mi></mrow><mrow><mn>4</mn></mrow></mmultiscripts></math> hyperfragment production in the 6Li( <italic>&#960;</italic> +, <italic>K</italic> +) reaction

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.

Observations of anomalous angular correlations in electron-positron pairs produced from excited states of <math xmlns="http://www.w3.org/1998/Math/MathML"><mmultiscripts><mi>He</mi><mprescripts></mprescripts><none></none><mn>4</mn></mmultiscripts><mo>,</mo><mo> </mo><mmultiscripts><mi>Be</mi><mprescripts></mprescripts><none></none><mn>8</mn></mmultiscripts></math>, and <math xmlns="http://www.w3.org/1998/Math/MathML"><mmultiscripts><mi mathvariant="normal">C</mi><mprescripts></mprescripts><none></none><mn>12</mn></mmultiscripts></math> nuclei have been suggested as being due to the creation and subsequent decay of a new light particle of mass <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mo>∼</mo><mn>17</mn><mspace width="0.16em"></mspace><mi>MeV</mi></mrow></math>. In this work, we investigate the possibility that the source of the observed signals is a set of new excitation channels created by the 12-quark hidden-color Fock state within the <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mmultiscripts><mi>He</mi><mprescripts></mprescripts><none></none><mrow><mn>4</mn></mrow></mmultiscripts></mrow></math> nuclear wave function dubbed the “hexadiquark.” We calculate the invariant <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msup><mi>e</mi><mo>+</mo></msup><msup><mi>e</mi><mo>−</mo></msup></mrow></math> mass spectrum for the electromagnetic transition from a new excitation of <math xmlns="http://www.w3.org/1998/Math/MathML"><mmultiscripts><mi>He</mi><mprescripts></mprescripts><none></none><mn>4</mn></mmultiscripts></math>, estimating its differential and total decay width. We find that we can fit the shape of the anomalous signal with the QCD Fock state at excitation energy <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msup><mi>E</mi><mo>*</mo></msup><mo>=</mo><mn>17.9</mn><mo>±</mo><mn>1</mn><mspace width="0.16em"></mspace><mi>MeV</mi></mrow></math> and a Gaussian form factor for the electromagnetic decay. We address the physical issues with the fit parameters using properties of the hexadiquark state, in particular the three weakly repulsive <math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mn>6</mn><mi>C</mi></msub></math> interactions of <math xmlns="http://www.w3.org/1998/Math/MathML"><msub><mrow><mi>SU</mi><mo>(</mo><mn>3</mn><mo>)</mo></mrow><mi>C</mi></msub></math> between diquark pairs. Experimental tests of our model are described in detail. In light of this work, we emphasize the need for independent experimental confirmation or refutation of the ATOMKI results as well as dedicated experiments to search for the proposed new excitations of <math xmlns="http://www.w3.org/1998/Math/MathML"><mmultiscripts><mi>He</mi><mprescripts></mprescripts><none></none><mn>4</mn></mmultiscripts></math> and other <math xmlns="http://www.w3.org/1998/Math/MathML"><mi>α</mi></math>-cluster nuclei.

United States

Valery Kubarovsky

Jennifer Rittenhouse West

Stanley J. Brodsky

Quantum chromodynamics resolution of the ATOMKI anomaly in <math xmlns="http://www.w3.org/1998/Math/MathML"><mmultiscripts><mi>He</mi><mprescripts></mprescripts><none></none><mn>4</mn></mmultiscripts></math> nuclear transitions

Superfluid <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mmultiscripts><mrow><mi>He</mi></mrow><mprescripts></mprescripts><none></none><mrow><mn>4</mn></mrow></mmultiscripts></mrow></math> is an ideal candidate for the direct detection of light dark matter via nuclear recoils thanks to its low nuclear mass and the possibility to reach a low-detection-energy threshold by exploiting the generated quasiparticles. The design of future detectors based on this target, such as the DELight experiment, requires a proper understanding of the formation and partitioning of the signal for different energy depositions from various sources. This work presents an overview of the physical processes involved in the energy deposition of recoiling electrons and ions, and it describes a Monte Carlo approach to the partitioning of the signal into different channels. Despite an overall good agreement with existing literature, differences in the region of interest for light dark matter searches below 200 eV are observed.

Francesco Toschi

Axel Brunold

Lea Burmeister

Klaus Eitel

Christian Enss

Eleanor Fascione

Torben Ferber

Rahel Gabriel

Lena Hauswald

Felix Kahlhoefer

Sebastian Kempf

Markus Klute

Belina von Krosigk

Sebastian Lindemann

United Kingdom

Benedikt Maier

Marc Schumann

Melih Solmaz

Kathrin Valerius

Friedrich Carl Wagner

Signal partitioning in superfluid <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mmultiscripts><mrow><mi>He</mi></mrow><mprescripts></mprescripts><none></none><mn>4</mn></mmultiscripts></mrow></math>: A Monte Carlo approach

We construct a holographic model to study the striped superconductor on ionic lattices. This model features a phase diagram with three distinct phases, namely the charge density wave (CDW) phase, ordinary superconducting phase (SC) and the striped superconducting phase (SSC). The effect of the ionic lattices on the phase diagram is investigated in detail. First, due to the periodic nature of the background, different types of CDW solutions can be found below the critical temperature. Furthermore, with the increase of the lattice amplitude these solutions are locked in different commensurate states. Second, we find that the critical temperature of CDW phase decreases with the increase of the lattice amplitude, while that of the SC phase increases. Additionally, the background solutions are obtained for different phases, and it is verified that the SSC phase has the lowest free energy among all three phases.

Kai Li

Yi Ling

Peng Liu

Meng-He Wu

Holographic striped superconductor with ionic lattice

We study the precession features of a test particle and gyroscope attached to a stationary observer in Horndeski rotating spacetime. First, we study the precession orbit, Lense-Thirring (LT) precession as well as periastron precession frequencies of the test particle, which are helpful to test the strong gravity of the central object and to distinguish Horndeski rotating black holes from naked singularities. We find that both LT frequency and periastron precession frequency of Horndeski rotating black hole and naked singularity behave differently when the particle's orbit approaches the innermost stable circular orbit. Also, the effects of Horndeski parameter on the two precession frequencies are explored. Second, we investigate the spin precession of a test gyroscope in the Horndeski rotating spacetime by analyzing the LT frequency, the geodetic precession frequency, and the general spin precession frequency for a stationary observer in the spacetime. The angle, spin parameter and Horndeski parameter modify all these frequencies, which make the results shift from those in Kerr spacetimes. Furthermore, these precession frequencies for the Horndeski rotating black hole and naked singularity are distinguishable. In particular, as the observer gets close to the central object in an arbitrary direction, the frequencies of Horndeski black hole grow significantly and become divergent, while for naked singularity they are finite. These theoretical results in some sense provide a potential method to “detect” event horizon, and to distinguish Horndeski theory from Einstein's general relativity.

Wen-Qi Zhen

Brazil

Hong Guo

Xiao-Mei Kuang

Orbital precession and Lense-Thirring effect of Horndeski rotating spacetimes

We investigate the Klein-Gordon (KG) oscillators in a global monopole (GM) spacetime in Eddington-inspired Born-Infeld (EiBI) gravity and a Wu-Yang magnetic monopole (WYMM). We discuss the gravitational effects in the presence of Ricci scalar curvature <math altimg='si1.svg'><mi>R</mi><mo linebreak='goodbreak' linebreakstyle='after'>=</mo><msubsup><mrow><mi>R</mi></mrow><mrow><mi>&#965;</mi></mrow><mrow><mi>&#965;</mi></mrow></msubsup></math>. It is observed that the presence of the Ricci scalar curvature, effectively and manifestly, introduces a force field that makes the corresponding quantum mechanical repulsive core more repulsive. Similar effect is also observed for the EiBI-gravitational field. We reiterate and report that the corresponding bosonic KG-oscillator quantum mechanical system admits a solution in the form of confluent Heun functions, the truncation of which into a physically admissible polynomial is shown to be associated with some parametric correlations/conditions. The use of such conditions/correlations is mandatory and yields a set of allowed/restricted quantum mechanical orbital <italic>&#8467;</italic>-excitations, for all radial quantum numbers <math altimg='si2.svg'><msub><mrow><mi>n</mi></mrow><mrow><mi>r</mi></mrow></msub><mo>&#8805;</mo><mn>0</mn></math>. Our procedure is shown to be quite handy, in the sense that it allows one to retrieve results for KG-oscillators in GM-spacetime in different EiBI-gravity and Ricci scalar curvature settings.

Türkiye

Omar Mustafa

KG-oscillators in Eddington-inspired Born-Infeld gravity: Wu-Yang magnetic monopole and Ricci scalar curvature effects

We investigate the geodesic motion of charged particles in the vicinity of regular black holes with a Minkowski core, embedded in a uniform magnetic field, and study the influences of magnetic field and regular black hole parameter on the radial effective potential and angular momentum of the particles’ orbits. We perturb the circular orbit and analyze the characteristic frequencies of the epicyclic oscillations, which are closely related with the quasiperiodic oscillations (QPOs) phenomena of the accretion disc surrounding the black hole. Then using the MCMC simulation, we fit our theoretical results with four observational QPOs events (GRO J1655-40, XTE J1550-564, XTE J1859+226, and GRS 1915+105) and provide constraints on the magnetic field strength , the characteristic radius , the mass , and the regular black hole parameter . In particular, since the parameter describes the degree of deviation from the classical Schwarzschild black hole, our studies suggest that, within a certain level of confidence, the black holes in the current model can deviate from the classical singularity structure of Schwarzschild black holes, and exhibit quantum corrections near the core.

Ming-Yu Guo

Parameter constraints on a black hole with Minkowski core through quasiperiodic oscillations

Precise direct cosmic-ray (CR) measurements provide an important probe to study the energetic particle sources in our Galaxy, and the interstellar environment through which these particles propagate. Uncertainties on hadronic models, ion-nucleon cross sections in particular, are currently the limiting factor toward obtaining more accurate CR ion flux measurements with calorimetric space-based experiments. We present an energy-dependent measurement of the inelastic cross section of protons and helium-4 nuclei (alpha particles) on a <math><mrow><msub><mrow><mi>Bi</mi></mrow><mrow><mn>4</mn></mrow></msub></mrow></math><math><msub><mtext>Ge</mtext><mn>3</mn></msub><msub><mi>O</mi><mn>12</mn></msub></math> target, using 88 months of data collected by the DAMPE space mission. The kinetic energy range per nucleon of the measurement points ranges from 18 GeV to 9 TeV for protons, and from <math><mrow><mn>5</mn><mtext> </mtext><mi>GeV</mi><mo>/</mo><mi>n</mi></mrow></math> to <math><mrow><mn>3</mn><mtext> </mtext><mtext> </mtext><mi>TeV</mi><mo>/</mo><mi>n</mi></mrow></math> for helium-4 nuclei. Our results lead to a significant improvement of the CR flux normalization. In the case of helium-4, these results correspond to the first cross section measurements on a heavy target material at energies above <math><mrow><mn>10</mn><mtext> </mtext><mi>GeV</mi><mo>/</mo><mi>n</mi></mrow></math>.

Italy

F. Alemanno

Q. An

Switzerland

P. Azzarello

F. C. T. Barbato

P. Bernardini

X. J. Bi

I. Cagnoli

M. S. Cai

E. Casilli

E. Catanzani

J. Chang

D. Y. Chen

J. L. Chen

Z. F. Chen

P. Coppin

M. Y. Cui

T. S. Cui

Y. X. Cui

H. T. Dai

A. De Benedittis

I. De Mitri

F. de Palma

A. Di Giovanni

Q. Ding

T. K. Dong

Z. X. Dong

G. Donvito

D. Droz

J. L. Duan

K. K. Duan

R. R. Fan

Y. Z. Fan

F. Fang

K. Fang

C. Q. Feng

L. Feng

J. M. Frieden

P. Fusco

M. Gao

F. Gargano

K. Gong

Y. Z. Gong

D. Y. Guo

J. H. Guo

S. X. Han

Y. M. Hu

G. S. Huang

X. Y. Huang

Y. Y. Huang

M. Ionica

L. Y. Jiang

Y. Z. Jiang

W. Jiang

J. Kong

A. Kotenko

D. Kyratzis

S. J. Lei

W. H. Li

W. L. Li

X. Li

X. Q. Li

Y. M. Liang

C. M. Liu

H. Liu

J. Liu

S. B. Liu

Y. Liu

F. Loparco

C. N. Luo

M. Ma

P. X. Ma

T. Ma

X. Y. Ma

G. Marsella

M. N. Mazziotta

D. Mo

X. Y. Niu

X. Pan

A. Parenti

W. X. Peng

X. Y. Peng

C. Perrina

E. Putti-Garcia

R. Qiao

J. N. Rao

A. Ruina

R. Sarkar

P. Savina

A. Serpolla

Z. Shangguan

W. H. Shen

Z. Q. Shen

Z. T. Shen

L. Silveri

J. X. Song

M. Stolpovskiy

H. Su

Hong Kong

M. Su

H. R. Sun

Z. Y. Sun

Hadronic cross section measurements with the DAMPE space mission using 20 GeV-10 TeV cosmic-ray protons and <math><mrow><mmultiscripts><mrow><mi>He</mi></mrow><mprescripts></mprescripts><none></none><mrow><mn>4</mn></mrow></mmultiscripts></mrow></math>