Chinese Physics C

2023-7 Contents

2023, 47(7): 1-2.

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Abstract:

Scalar leptoquark and vector-like quark extended models as the explanation of the muon g–2 anomaly: bottom partner chiral enhancement case

Shi-Ping He

2023, 47(7): 073101. doi: 10.1088/1674-1137/accc1d

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Abstract:
Leptoquark (LQ) models are well motivated solutions to the

\begin{document}$ (g-2)_{\mu} $\end{document}

anomaly. In the minimal LQ models, only specific representations can lead to chiral enhancements. For the scalar LQs,

\begin{document}$ R_2 $\end{document}

and

\begin{document}$ S_1 $\end{document}

can lead to the top quark chiral enhancement. For the vector LQs,

\begin{document}$ V_2 $\end{document}

and

\begin{document}$ U_1 $\end{document}

can lead to the bottom quark chiral enhancement. When we consider the LQ and vector-like quark (VLQ) simultaneously, there can be more scenarios. In our previous study, we considered the scalar LQ and VLQ extended models with up-type quark chiral enhancement. Here, we study the scalar LQ and VLQ extended models with down-type quark chiral enhancement. We find two new models with B quark chiral enhancements, which originate from the bottom and bottom partner mixing. Then, we propose new LQ and VLQ search channels under the constraints of

\begin{document}$ (g-2)_{\mu} $\end{document}

.

Decay properties of ${ \boldsymbol D_{\boldsymbol s0}^*{\bf{(2317)}}^{\bf +} }$ as a conventional ${\boldsymbol c\bar {\boldsymbol s}} $ meson

Meng Han, Wei Li, Su-Yan Pei, Ting-Ting Liu, Guo-Li Wang

2023, 47(7): 073102. doi: 10.1088/1674-1137/acd367

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Abstract:
Taking

\begin{document}$D_{s0}^{*}(2317)^{+ } $\end{document}

as a conventional

\begin{document}$c\bar s $\end{document}

meson, we calculate its dominant strong and electromagnetic decays in the framework of the Bethe-Salpeter method. Our results are

\begin{document}$\Gamma(D_{s0}^{*+}\to D_s^+\pi^0) = 7.83^{+1.97}_{-1.55} $\end{document}

keV and

\begin{document}$\Gamma(D_{s0}^{*+}\to D_s^{*+}\gamma) = 2.55^{+0.37}_{-0.45} $\end{document}

keV. The contributions of the different partial waves from the initial and final state wave functions to the decay width are also calculated, and we find that the relativistic corrections in both decay processes are very large.

Triangle mechanism in the decay process $ {\boldsymbol B_{\bf 0}{\bf \to}{\boldsymbol J}{\bf /}\boldsymbol\psi {\boldsymbol K}^{\bf 0} {\boldsymbol f}_{\bf 0}{\bf (980)}({\boldsymbol a}_{\bf 0}{\bf(980))} }$

Jialiang Lu, Xuan Luo, Mao Song, Gang Li

2023, 47(7): 073103. doi: 10.1088/1674-1137/accf6d

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Abstract:
The role of the triangle mechanism in the decay processes

\begin{document}$ B_0\to J/\psi K^0f_0 \to J/\psi K^0\pi^+\pi^- $\end{document}

and

\begin{document}$ B_0\to J/\psi K^0a_0\to J/\psi K^0 \pi^0\eta $\end{document}

is probed. In these processes, the triangle singularity appears from the decay of

\begin{document}$ B^0 $\end{document}

into

\begin{document}$ J/\psi\phi K^0 $\end{document}

, and then, ϕ decays into

\begin{document}$ K^0\bar{K^0} $\end{document}

and

\begin{document}$ K^0\bar{K^0} $\end{document}

merged into

\begin{document}$ f_0 $\end{document}

or

\begin{document}$ a_0 $\end{document}

, which finally decay into

\begin{document}$ \pi^+\pi^- $\end{document}

and

\begin{document}$ \pi^0\eta $\end{document}

, respectively. We find that this mechanism leads to a triangle singularity around

\begin{document}$ M_{\rm inv}(K^0f_0(a_0))\approx1520\ {\rm MeV} $\end{document}

and gives sizable branching fractions

\begin{document}$ {\rm{Br}}(B_0\to J/\psi K^0f_0\to J/\psi K^0\pi^+\pi^-)=7.67\times10^{-7} $\end{document}

and

\begin{document}${\rm{Br}}(B_0\to J/\psi K^0a_0 \to $\end{document}

\begin{document}$ J/\psi K^0\pi^0\eta)= 1.42\times10^{-7}$\end{document}

. This investigation can help us obtain the information of the scalar meson

\begin{document}$ f_0(980) $\end{document}

or

\begin{document}$ a_0(980) $\end{document}

.

Quasi-two-body decays ${ \boldsymbol B_{\boldsymbol c}{\bf\to} {\boldsymbol D}^*{\boldsymbol h}{\bf\to}{\boldsymbol D}{\boldsymbol\pi}{\boldsymbol h} }$ in perturbative QCD

Yan-Chao Zhao, Zhi-Qing Zhang, Zi-Yu Zhang, Zhi-Jie Sun, Qiu-Bo Meng

2023, 47(7): 073104. doi: 10.1088/1674-1137/acd23e

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Abstract:
In this work, we investigate the quasi-two-body decays

\begin{document}$ B_c\to D^*h\to D\pi h $\end{document}

with

\begin{document}$ h = (K^0,\pi^0,\eta,\eta^{\prime}) $\end{document}

using the perturbative QCD (PQCD) approach. The description of final state interactions of the

\begin{document}$ D\pi $\end{document}

pair is achieved through the two-meson distribution amplitudes (DAs), which are normalized to the time-like form factor. The PQCD predictions on the branching ratios of the quasi-two-body decays

\begin{document}$ B_c\to D^*h\to D\pi h $\end{document}

show an obvious hierarchy:

\begin{document}${\rm Br}(B_{c}^+ \to D^{*+} K^{0}\to D^0\pi^+K^{0})=({5.22}_{-0.74}^{+0.86})\times{10}^{-6},\;\; {\rm Br}(B_{c}^+ \to D^{*+} \pi^{0}\to D^0\pi^+\pi^{0})=(0.93\pm0.26)\times{10}^{-7},$\end{document}

\begin{document}${\rm Br}(B_{c}^+ \to $\end{document}

\begin{document}$ D^{*+} \eta\to D^0\pi^+\eta) = ({2.83}_{-0.52}^{+0.59})\times{10}^{-8}$\end{document}

and

\begin{document}${\rm Br}(B_{c}^+ \to D^{*+} \eta^\prime\to D^0\pi^+\eta^\prime)=({1.89}_{-0.36}^{+0.40})\times{10}^{-8}$\end{document}

. From the invariant mass

\begin{document}$ m_{D\pi} $\end{document}

-dependence of the decay spectrum for each channel, one can find that the branching fraction is concentrated in a narrow region around the

\begin{document}$ D^{*} $\end{document}

pole mass. Thus, one can obtain the branching ratios for the corresponding two-body decays

\begin{document}$ B_c\to D^{*+}h $\end{document}

under the narrow-width approximation. We find that the branching ratios of the decays

\begin{document}$ B_c\to D^{*+}h $\end{document}

are consistent with the previous PQCD calculations within errors. These predictions will be tested in future experiments.

Systematic analysis of strange single heavy baryons ${ \boldsymbol\Xi_{\boldsymbol c} }$ and ${\boldsymbol\Xi_{\boldsymbol b} }$

Zhen-Yu Li, Guo-Liang Yu, Zhi-Gang Wang, Jian-Zhong Gu, Jie Lu, Hong-Tao Shen

2023, 47(7): 073105. doi: 10.1088/1674-1137/acd365

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Abstract:
Motivated by the experimental progress in the study of heavy baryons, we investigate the mass spectra of strange single heavy baryons in the λ-mode, using the relativistic quark model and the infinitesimally shifted Gaussian basis function method. We show that experimental results are well captured using the predicted masses. The root mean square radii and radial probability density distributions of the wave functions are analyzed in detail. Meanwhile, the mass spectra allow us to successfully construct the Regge trajectories in the

\begin{document}$ (J,M^{2}) $\end{document}

plane. We also preliminarily assign quantum numbers to the recently observed baryons, including

\begin{document}$ \Xi_{c}(3055) $\end{document}

,

\begin{document}$ \Xi_{c}(3080) $\end{document}

,

\begin{document}$ \Xi_{c}(2930) $\end{document}

,

\begin{document}$ \Xi_{c}(2923) $\end{document}

,

\begin{document}$ \Xi_{c}(2939) $\end{document}

,

\begin{document}$ \Xi_{c}(2965) $\end{document}

,

\begin{document}$ \Xi_{c}(2970) $\end{document}

,

\begin{document}$ \Xi_{c}(3123) $\end{document}

,

\begin{document}$ \Xi_{b}(6100) $\end{document}

,

\begin{document}$ \Xi_{b}(6227) $\end{document}

,

\begin{document}$ \Xi_{b}(6327) $\end{document}

, and

\begin{document}$ \Xi_{b}(6333) $\end{document}

. Finally, the spectral structure of strange single heavy baryons is discussed. Accordingly, we predict several new baryons that may be observed in forthcoming experiments.

Lepton flavor violating decays of vector mesons in the MRSSM

Ke-Sheng Sun, Wen-Hui Zhang, Jian-Bin Chen, Hai-Bin Zhang, Qi-geng Yan

2023, 47(7): 073106. doi: 10.1088/1674-1137/acd3da

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In this study, we analyze the rare decays of the neutral vector mesons

\begin{document}$ J/\psi $\end{document}

and

\begin{document}$ \Upsilon(nS) $\end{document}

in the scenario of the minimal R-symmetric supersymmetric standard model using the effective Lagrangian method. The predicted branching ratios are dominated by the mass insertion parameters

\begin{document}$ \delta^{ij} $\end{document}

, i.e., the off-diagonal inputs, and the contributions of different parts are comparable. Taking into account the experimental constraints on the mass insertion parameters, the predicted branching ratios for the most promising processes

\begin{document}$ \Upsilon(nS)\rightarrow l\tau $\end{document}

are ten orders of magnitude smaller than the present experimental bounds.

Measurement of neutron capture cross section on ⁷¹Ga at 2.15 and 3.19 MeV and uncertainty propagation and covariance analysis

Rebecca Pachuau, A. Gandhi, Namrata Singh, A. Kumar, Mayur Mehta, S. V. Suryanarayana, L. S. Danu, B. K. Nayak, B. Lalremruata

2023, 47(7): 074001. doi: 10.1088/1674-1137/acce28

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Abstract:
The cross section values of the

\begin{document}$ ^{71} $\end{document}

Ga(

\begin{document}$n, \gamma $\end{document}

)

\begin{document}$ ^{72} $\end{document}

Ga reaction are measured, which are

\begin{document}$9.14 \pm 0.81$\end{document}

mb and

\begin{document}$5.74 \pm 0.50$\end{document}

mb at 2.15 and 3.19 MeV, respectively. The detailed uncertainty propagation and covariance analysis are also given. The

\begin{document}$ ^{7} $\end{document}

Li(

\begin{document}$p,n$\end{document}

)

\begin{document}$ ^{7} $\end{document}

Be reaction was used to generate the neutrons, and the neutron flux was normalized using the

\begin{document}$ ^{115} $\end{document}

In(

\begin{document}$n,n'$\end{document}

)

\begin{document}$ ^{115} $\end{document}

In

\begin{document}$ ^{m} $\end{document}

monitor reaction. The measured cross section data are compared with the data available in the EXFOR database, the data obtained using nuclear reaction model codes EMPIRE-3.2 and TALYS-1.95, and also the evaluated nuclear data from ENDF/B-VIII.0 and JEFF-3.1/A. The comparison shows that our result at 3.19 MeV is in good agreement with those of EMPIRE-3.2 and JEFF-3.1/A. Since there are no other measurements available at 3.19 MeV, our data could not be compared with literature data at 3.19 MeV, but they are consistent with the cross section values available at

\begin{document}$2.98 \pm 0.26$\end{document}

and

\begin{document}$3.0 \pm 0.1 $\end{document}

MeV. Our result at 2.15 MeV is slightly higher than the literature value available in EXFOR, evaluated value, and theoretically predicted result.

Gluon gravitational form factors of protons from charmonium photoproduction

Xiao-Yun Wang, Fancong Zeng, Quanjin Wang

2023, 47(7): 074101. doi: 10.1088/1674-1137/accc1e

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Inspired by the recent near-threshold

\begin{document}$ J/\psi $\end{document}

photoproduction measurements, we discuss gluon gravitational form factors (GFFs) and internal properties of the proton. This work presents a complete analysis of the proton gluon GFFs connecting the gluon part of the energy-momentum tensor and the heavy quarkonium photoproduction. In particular, a global fitting of the

\begin{document}$J/\psi $\end{document}

differential and total cross section experimental data is used to determine the gluon GFFs as functions of the squared momentum transfer t. Combined with the quark contributions to the D-term form factor extracted from the deeply virtual Compton scattering experiment, the total D-term is obtained to investigate their applications in describing the proton mechanical properties. These studies provide a unique perspective on investigating the proton gluon GFFs and important information for enhancing QCD constraints on the gluon GFFs.

Weighted variation after projection method for low-lying nonyrast states

Zhan-Jiang Lian, Xiao Lu, Xue-Wei Li, Zao-Chun Gao, Yong-Shou Chen

2023, 47(7): 074102. doi: 10.1088/1674-1137/acccda

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Abstract:
We propose a simple algorithm to further improve the previous variation after projection (VAP) wave functions for low-lying nonyrast states. We attach a weight factor to each calculated energy; then, the sum of these weighted energies is minimized. It turns out that a low-lying nonyrast VAP wave function can be further optimized when the weight factor for the corresponding energy is far larger than the other ones. Based on the improved WVAP wave functions, the energy-variance extrapolation method is applied to estimate the exact shell model energies. The calculated results for nuclei in the

\begin{document}$ sd $\end{document}

and

\begin{document}$ pf $\end{document}

model spaces clearly show that the extrapolated energies for all the calculated states are very close to the exact shell model ones within

\begin{document}$ 10 $\end{document}

keV.

Monopole effects and high-spin levels in neutron-rich ¹³²Te

Han-Kui Wang, Amir Jalili, Ge-Xing Li, You-Bao Wang

2023, 47(7): 074103. doi: 10.1088/1674-1137/accdc6

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The neutron-rich nuclei near doubly magic

\begin{document}$ ^{132} $\end{document}

Sn have attracted considerable interest in both nuclear physics and nuclear astrophysics. For the particle-hole nuclei in this region, the low-lying and high core excitations have been well described by shell model calculations using the extended pairing plus multipole-multipole force model. However, there is a significant difference between experiment and theory in the high-spin level 17

\begin{document}$ ^+ $\end{document}

of

\begin{document}$ ^{132} $\end{document}

Te. We intend to illustrate this difference through monopole interactions. For this purpose, the monopole corrections between

\begin{document}$\pi(\nu)0g_{7/2},~ \nu 1d_{5/2}$\end{document}

and

\begin{document}$ \pi(\nu)0h_{11/2} $\end{document}

are investigated in

\begin{document}$ ^{132-134} $\end{document}

Te,

\begin{document}$ ^{131-133} $\end{document}

Sb, and

\begin{document}$ ^{130} $\end{document}

Sn. Some theoretical levels are connected to the (17

\begin{document}$ ^+ $\end{document}

) state of

\begin{document}$ ^{132} $\end{document}

Te with the monopole correction (Mc) of

\begin{document}$ Mc(\nu d_{5/2},\nu h_{11/2}) $\end{document}

and the quadruple-quadruple force between the proton and neutron, i.e., levels 3

\begin{document}$ ^- $\end{document}

(8

\begin{document}$ ^- $\end{document}

) in

\begin{document}$ ^{130} $\end{document}

Sn, level 14

\begin{document}$ ^- $\end{document}

in

\begin{document}$ ^{132} $\end{document}

Te, and level 23/2

\begin{document}$ ^- $\end{document}

in

\begin{document}$ ^{131} $\end{document}

Sb. Their observations at lower energies can confirm the datum of level (17

\begin{document}$ ^+ $\end{document}

) in

\begin{document}$ ^{132} $\end{document}

Te with an illustration of monopole effects and quadruple-quadruple force.

Finding optimal basis states for variation after projection nuclear wave functions

Xiao Lu, Zhan-Jiang Lian, Xue-Wei Li, Zao-Chun Gao, Yong-Shou Chen

2023, 47(7): 074104. doi: 10.1088/1674-1137/accf08

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Abstract:
The variation after projection (VAP) method is expected to be an efficient way of obtaining the optimized nuclear wave functions, which can be as close as possible to the exact shell model ones. However, we found that there are two additional problems that may seriously affect the convergence of the VAP iteration. The first problem is the existence of irrelevant projected basis states. At a VAP iteration, the Hill-Wheeler (HW) equation is composed of all updated projected basis states. If one of these projected basis states does not mix with a calculated wave function of interest, which is obtained by solving this HW equation, it is likely that this basis state will never mix with this wave function even after the VAP iteration converges. The other problem is the poor orthonormality among the projected basis states, which seriously affects the accuracy of the calculated VAP wave function. In the present work, solutions for these two problems are proposed, and examples are presented to test the validity. With the present solutions, the most important projected basis states can be reliably obtained, and the fully optimized VAP wave functions can be accurately and efficiently calculated.

Systematic studies on the nuclear parton distribution with photon and hadron productions in nuclear collisions at the LHC

Xing-Long Li, Ya Zhu, Xiao-Ming Zhang, Dai-Cui Zhou

2023, 47(7): 074105. doi: 10.1088/1674-1137/accad6

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A systematic study on the impact of widely-used nuclear-modified parton distribution function (nPDF) parameterizations on the production of direct photons and charged hadrons is performed by employing a next-to-leading order Monte Carlo event generator JETPHOX in hadronic collisions at LHC energies. The nuclear modification factors of photon and charged hadron productions are studied in three types of collision systems, i.e., small (

\begin{document}$ p+p $\end{document}

and

\begin{document}$ p+{\rm{Pb}} $\end{document}

), medium

\begin{document}$\rm (O+O) $\end{document}

, and large

\begin{document}$\rm (Pb+Pb) $\end{document}

, in a wide rapidity acceptance. The results illustrate that the direct photon production process is a sensitive probe to decipher the difference of the nPDF parameterization implementations, which provides new insights for the experimental measurements to refine the nuclear modifications of the parton distributions. To provide a benchmark for searching for quark gluon plasma in the upcoming small system measurements at LHC energies, we carry out detailed studies on the cold nuclear matter effect in

\begin{document}$\rm (O+O) $\end{document}

collisions. Our outcomes show that the cold nuclear matter effects are negligible for the charged hadron production in

\begin{document}$\rm (O+O) $\end{document}

collisions, which can be used as a baseline to subtract the initial state contribution.

Preformation probability and kinematics of cluster emission yielding Pb-daughters

Joshua T. Majekodunmi, M. Bhuyan, K. Anwar, N. Abdullah, Raj Kumar

2023, 47(7): 074106. doi: 10.1088/1674-1137/acbf2b

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In the present study, the newly established preformation formula is applied for the first time to study the kinematics of the cluster emission from various radioactive nuclei, especially those that decay to the double shell closure

\begin{document}$ ^{208} $\end{document}

Pb nucleus and its neighbors as daughters. The recently proposed universal cluster preformation formula has been established based on the concepts that underscore the influence of mass and charge asymmetry (

\begin{document}$ \eta_A $\end{document}

and

\begin{document}$ \eta_Z $\end{document}

), cluster mass

\begin{document}$ A_c $\end{document}

, and the Q-value, paving the way to quantify the energy contribution during preformation as well as during the tunneling process separately. The cluster-daughter interaction potential is obtained by folding the relativistic mean-field (RMF) densities with the recently developed microscopic R3Y using the NL

\begin{document}$ 3^* $\end{document}

and the phenomenological M3Y NN potentials to compare their adaptability. The penetration probabilities are calculated from the WKB approximation. With the inclusion of the new preformation probability

\begin{document}$ P_0 $\end{document}

, the predicted half-lives of the R3Y and M3Y interactions are in good agreement with the experimental data. Furthermore, a careful inspection reflects slight differences in the decay half-lives, which arise from their respective barrier properties. The

\begin{document}$ P_0 $\end{document}

for systems with double magic shell closure

\begin{document}$ ^{208} $\end{document}

Pb daughter are found to be an order of

\begin{document}$ \approx 10^2 $\end{document}

higher than those with neighboring Pb daughter nuclei. By exploring the contributions of the decay energy, the recoil effect of the daughter nucleus is evaluated, in contrast to several other conjectures. Thus, the centrality of the

\begin{document}$Q$\end{document}

-value in the decay process is demonstrated and redefined within the preformed cluster-decay model. Additionally, we have introduced a simple and intuitive set of criteria that governs the estimation of recoil energy in the cluster radioactivity.

Light nuclei production in Au+Au collisions at ${ \sqrt{{\boldsymbol s}_{\boldsymbol N \boldsymbol N}}} \boldsymbol{=}$ 3 GeV from coalescence model

Yue Xu, Xionghong He, Nu Xu

2023, 47(7): 074107. doi: 10.1088/1674-1137/acd3d9

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The nucleon coalescence model is one of the most popular theoretical models for light nuclei production in high-energy heavy-ion collisions. The production of light nuclei d, t,

\begin{document}$ ^{3} $\end{document}

He, and

\begin{document}$ ^{4} $\end{document}

He is studied using the transport model JAM with a simplified afterburner coalescence at

\begin{document}$ \sqrt{s_{NN}}=3 $\end{document}

GeV Au+Au collisions. We scan the cut-off of phenomenological coalescence parameters, i.e., the relative spatial distance

\begin{document}$ \Delta R $\end{document}

and momentum difference

\begin{document}$ \Delta P $\end{document}

, for the formation of light nuclei by nucleon coalescence to reproduce the light nuclei

\begin{document}$p_{T}$\end{document}

spectra measured by the STAR experiment. The results indicate a potential connection between the coalescence parameters and the binding energy as well as the diameter of these light nuclei.

Examination of machine learning for assessing physical effects: Learning the relativistic continuum mass table with kernel ridge regression

Xiao-Kai Du, Peng Guo, Xin-Hui Wu, Shuang-Quan Zhang

2023, 47(7): 074108. doi: 10.1088/1674-1137/acc791

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Abstract:
The kernel ridge regression (KRR) method and its extension with odd-even effects (KRRoe) are used to learn the nuclear mass table obtained by the relativistic continuum Hartree-Bogoliubov theory. With respect to the binding energies of 9035 nuclei, the KRR method achieves a root-mean-square deviation of 0.96 MeV, and the KRRoe method remarkably reduces the deviation to 0.17 MeV. By investigating the shell effects, one-nucleon and two-nucleon separation energies, odd-even mass differences, and empirical proton-neutron interactions extracted from the learned binding energies, the ability of the machine learning tool to grasp the known physics is discussed. It is found that the shell effects, evolutions of nucleon separation energies, and empirical proton-neutron interactions are well reproduced by both the KRR and KRRoe methods, although the odd-even mass differences can only be reproduced by the KRRoe method.

Superradiance of massive scalar particles around rotating regular black holes

Hao Yang, Yan-Gang Miao

2023, 47(7): 075101. doi: 10.1088/1674-1137/accdc7

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Regular black holes, as part of an important attempt to eliminate the singularities in general relativity, have been of wide concern. Because the superradiance associated with rotating regular black holes plays an indispensable role in black hole physics, we calculate the superradiance related effects, i.e., the superradiance instability and the energy extraction efficiency, for a scalar particle with a small mass around a rotating regular black hole, where the rotating regular black hole is constructed by the modified Newman-Janis algorithm. We analytically give the eigenfrequency associated with instability and the amplification factor associated with energy extraction. For two specific models, i.e., the rotating Hayward and Bardeen black holes, we investigate how their regularization parameters affect the growth of instability and the efficiency of energy extraction from the two rotating regular black holes. We find that the regularization parameters give rise to different modes of the superradiance instability and the energy extraction when the rotation parameters vary. There are two modes for the growth of superradiance instability and four modes for the energy extraction. Our results show the diversity of superradiance in the competition between the regularization parameter and the rotation parameter for rotating regular black holes.

Non-exotic static spherically symmetric thin-shell wormhole solution in f (Q, T ) gravity

Moreshwar Tayde, Sayantan Ghosh, P.K. Sahoo

2023, 47(7): 075102. doi: 10.1088/1674-1137/acd2b7

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In this study, we conduct an analysis of traversable wormhole solutions within the framework of linear

\begin{document}$ f(Q, T) = \alpha Q + \beta T $\end{document}

gravity, ensuring that all energy conditions hold for the entire spacetime. The solutions presented in this paper are derived through a comprehensive analytical examination of the parameter space associated with the wormhole model. This involves considering the exponents governing the redshift and shape functions, as well as the radius of the wormhole throat (

\begin{document}$ r_0 $\end{document}

), the redshift function value at the throat (

\begin{document}$ \phi_0 $\end{document}

), and the model parameters (α and β). Moreover, we establish bounds on these free parameters, which guarantee the satisfaction of the energy conditions throughout spacetime and also provide two solutions. Furthermore, we use the Israel junction condition to observe the stability of a thin-shell around the wormhole. Finally, we calculate the null energy condition criteria as well as the potential for the thin-shell and how it varies with the chosen shape function.

Probing Hořava-Lifshitz gravity using particle and photon dynamics in the presence of plasma

Mirzabek Alloqulov, Farruh Atamurotov, Ahmadjon Abdujabbarov, Bobomurat Ahmedov

2023, 47(7): 075103. doi: 10.1088/1674-1137/acd43c

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Abstract:
We study the particle motion around a black hole (BH) in Hořava-Lifshitz (HL) gravity with the Kehagias-Sfetsos (KS) parameter. First, the innermost stable circular orbit (ISCO) is obtained for massive particles around the BH in HL gravity. We find that the radii of the ISCOs decrease as the KS parameter decreases, meaning that the parameter

\begin{document}$ \Omega$\end{document}

causes the orbits of particles to move inward with respect to that of the Schwarzschild BH case. Then, the optical properties of a KS BH are studied in detail, that is, the BH shadow and gravitational weak lensing. We demonstrate that the size of the BH shadow decreases under the influence of the KS parameter.

2023 Vol. 47, No. 7