Journal of High Energy Astrophysics最新文献

{"title":"A universal energy relation between synchrotron and synchrotron self-Compton radiation in GRBs and blazars","authors":"Tao Wen ,&nbsp;Yu-Hua Yao ,&nbsp;Song-Zhan Chen ,&nbsp;Ben-Zhong Dai ,&nbsp;Yi-Qing Guo","doi":"10.1016/j.jheap.2024.10.007","DOIUrl":"10.1016/j.jheap.2024.10.007","url":null,"abstract":"<div><div>The recent and brightest GRB 221009A observed by LHAASO marked the first detection of the onset of TeV afterglow, with a total of 7 GRBs exhibiting very high energy (VHE) afterglow radiation. However, consensus on VHE radiation of GRBs is still lacking. Multi-wavelength studies are currently a primary research method for investigating high-energy <em>γ</em>-ray astronomy. The limited sample of VHE GRBs, combined with their transient nature, hinders the progress of physical studies of GRBs. This paper aims to obtain useful information for GRB research through the properties of blazars, which share significant similarities with GRBs. By fitting high-quality and simultaneous multiwavelength spectral energy distributions with a one-zone leptonic model, the study explores the similarity of radiation properties of blazars and GRBs. A tight correlation between synchrotron and synchrotron self-Compton (SSC) emission luminosities suggests that blazars and GRBs share similar radiation mechanisms, to be specific, synchrotron radiation produces the observed X-ray photons, which also serve as targets for electrons in the SSC process. We hope that ground-based experiments can observe more GRBs in sub-TeV to confirm these findings.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"44 ","pages":"Pages 315-322"},"PeriodicalIF":10.2,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142444817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bouncing universe scenarios in an extended gravitational framework involving curvature-matter coupling","authors":"M. Zubair ,&nbsp;Quratulien Muneer ,&nbsp;Saira Waheed ,&nbsp;G. Dilara Açan Yildiz ,&nbsp;Ertan Gudekli","doi":"10.1016/j.jheap.2024.10.005","DOIUrl":"10.1016/j.jheap.2024.10.005","url":null,"abstract":"<div><div>Exploration of bouncing cosmic models in modified theories has gained much popularity in modern cosmology. This paper explores the Lagrangian function of a new theory namely <span><math><mi>F</mi><mo>(</mo><mi>R</mi><mo>,</mo><msub><mrow><mi>L</mi></mrow><mrow><mi>m</mi></mrow></msub><mo>,</mo><mi>T</mi><mo>)</mo></math></span> framework by taking four renowned cosmic bouncing models, i.e., the exponential bounce, oscillatory bounce scenario, power law, and matter bouncing. Our primary objective is to fix the form of <span><math><mi>F</mi><mo>(</mo><mi>R</mi><mo>,</mo><msub><mrow><mi>L</mi></mrow><mrow><mi>m</mi></mrow></msub><mo>,</mo><mi>T</mi><mo>)</mo></math></span> function for each model and investigate which kinds of reconstructed Lagrangian function have potential of regenerating bouncing scenario in terms of analytical form. It is seen that except power law model, the analytical solutions are conceivable only for certain cases of these bouncing models. For power law bounce, different cases of Lagrangian function may be rebuilt analytically while for some other bouncing scenarios, it is found that particular solutions are not always attainable and hence only the complimentary solutions can be explored. Further, we examine the behavior of energy constraints and stability of these analytically formed bouncing solutions. Additionally, we determine that the dark energy phase in <span><math><mi>F</mi><mo>(</mo><mi>R</mi><mo>,</mo><msub><mrow><mi>L</mi></mrow><mrow><mi>m</mi></mrow></msub><mo>,</mo><mi>T</mi><mo>)</mo></math></span> gravity is compatible with the experimental data of BAO+Sne-Ia+CMB+H(z) and it is shown that cosmic bounce can be produced with dark energy eras in this gravity. We also present some constraints on the model parameters with Hubble parameter values and ΛCDM to determine the best-fit values of model via least square and reduced chi-squares methods. It is concluded that matter bounce model is the best fitted with the observational data set as well as ΛCDM model because it has least value of <span><math><msubsup><mrow><mi>χ</mi></mrow><mrow><mi>m</mi></mrow><mrow><mn>2</mn></mrow></msubsup></math></span>.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"44 ","pages":"Pages 243-265"},"PeriodicalIF":10.2,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142433060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reconstructing inflationary potential from NANOGrav 15-year data: A robust study using Non-Bunch Davies initial condition","authors":"Sayantan Choudhury","doi":"10.1016/j.jheap.2024.10.003","DOIUrl":"10.1016/j.jheap.2024.10.003","url":null,"abstract":"<div><div>We discuss the theoretical framework behind reconstruction of a generic class of inflationary potentials for canonical single-field slow-roll inflation in a model-independent fashion. The Non-Bunch Davies (NBD) initial condition is an essential choice to determine the structure of potential and to accommodate the blue-tilted tensor power spectrum feature recently observed in NANOGrav. Using the reconstruction technique we found the favoured parameter space which supports blue tilted tensor power spectrum. The validity of the EFT prescription in inflation is also maintained through the use of a new field excursion formula while keeping the necessary and sufficient conditions on the sub-Planckian field values in check. We find that the reconstructed potential display inflection point behaviour, which has deeper connection with high energy physics.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"44 ","pages":"Pages 220-242"},"PeriodicalIF":10.2,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142433059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On the evaluation of accretion process near a quantum-improved charged black hole","authors":"G. Murtaza ,&nbsp;A. Ditta ,&nbsp;Tayyab Naseer ,&nbsp;G. Mustafa ,&nbsp;S.K. Maurya ,&nbsp;A. Ghaffar ,&nbsp;Faisal Javed","doi":"10.1016/j.jheap.2024.10.004","DOIUrl":"10.1016/j.jheap.2024.10.004","url":null,"abstract":"<div><div>This paper deals with astrophysical accretion onto the quantum-improved charged black hole. An accretion process does not depend on time; it is a stationary process. In this analysis, we explore the physical quantities like energy density, radial velocity, sonic speed, and accretion mass rate for quantum-improved charged black holes and compare them with the existing outcomes corresponding to the Schwarzschild black hole. Following the Michel and Babichev approaches, we investigate the quantities mentioned above by taking into account different equations of state. These fundamental approaches and black hole parameters are responsible for decreasing the fluid's radial infalling velocity during the accretion process and, for others, as a gravitational enhancer, increasing the fluid flow into the black hole horizon. The polytropic fluid's accretion process is also discussed. All the quantities are analyzed graphically with a contour structure. It is observed that the maximum accretion rate is achieved for different values of the considered black hole parameters. From this analysis, we may be able to understand the physical mechanism of accretion onto a quantum-improved charged black hole.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"44 ","pages":"Pages 279-289"},"PeriodicalIF":10.2,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142433062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Standardised formats and open-source analysis tools for the MAGIC telescopes data","authors":"","doi":"10.1016/j.jheap.2024.09.011","DOIUrl":"10.1016/j.jheap.2024.09.011","url":null,"abstract":"<div><div>Instruments for gamma-ray astronomy at Very High Energies (<span><math><mi>E</mi><mo>&gt;</mo><mn>100</mn><mspace></mspace><mrow><mi>GeV</mi></mrow></math></span>) have traditionally derived their scientific results through proprietary data and software. Data standardisation has become a prominent issue in this field both as a requirement for the dissemination of data from the next generation of gamma-ray observatories and as an effective solution to realise public data legacies of current-generation instruments. Specifications for a standardised gamma-ray data format have been proposed as a community effort and have already been successfully adopted by several instruments. We present the first production of standardised data from the Major Atmospheric Gamma-ray Imaging Cherenkov (MAGIC) telescopes. We converted <span><math><mn>166</mn><mspace></mspace><mi>h</mi></math></span> of observations from different sources and validated their analysis with the open-source software <span>Gammapy</span>. We consider six data sets representing different scientific and technical analysis cases and compare the results obtained analysing the standardised data with open-source software against those produced with the MAGIC proprietary data and software. Aiming at a systematic production of MAGIC data in this standardised format, we also present the implementation of a database-driven pipeline automatically performing the MAGIC data reduction from the calibrated down to the standardised data level. In all the cases selected for the validation, we obtain results compatible with the MAGIC proprietary software, both for the manual and for the automatic data productions. Part of the validation data set is also made publicly available, thus representing the first large public release of MAGIC data. This effort and this first data release represent a technical milestone toward the realisation of a public MAGIC data legacy.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"44 ","pages":"Pages 266-278"},"PeriodicalIF":10.2,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142433061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Study in the non-canonical domain of power law Plateau inflation","authors":"Yogesh ,&nbsp;Mayukh R. Gangopadhyay","doi":"10.1016/j.jheap.2024.10.002","DOIUrl":"10.1016/j.jheap.2024.10.002","url":null,"abstract":"<div><div>The recent Cosmic Microwave Background (CMB) observations are pointing towards a plateau feature in the flat potential of the inflation field to drive the initial acceleration of the Universe. In this regard, Dimopoulos and Owen introduced a very promising model dubbed as Power Law Plateau inflation (PLP) (<span><span>Dimopoulos and Owen, 2016</span></span>) which has this feature in it. But to make this model consistent with observation in the standard cold inflationary scenario, one needs to introduce an epoch of thermal inflation. In this paper, we have shown realizing this model in the non-canonical domain, could actually make the model consistent with the observation without introducing any late-stage thermal inflation. We also report the constraints from the Cosmic Microwave Background observations on the reheating parameter that one can associate with the model parameter.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"44 ","pages":"Pages 214-219"},"PeriodicalIF":10.2,"publicationDate":"2024-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142433133","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Search for GeV gamma-ray emission from SPT-CL J2012-5649 with six years of DAMPE data","authors":"Siddhant Manna,&nbsp;Shantanu Desai","doi":"10.1016/j.jheap.2024.10.001","DOIUrl":"10.1016/j.jheap.2024.10.001","url":null,"abstract":"<div><div>We search for gamma-ray emission from the galaxy cluster SPT-CL J2012-5649 in the energy range from 3 GeV to 1 TeV using the DArk Matter Particle Explorer (DAMPE) telescope. For our analysis, we use three different templates: point source, radial disk, and radial Gaussian. We do not detect a signal with significance <span><math><mo>&gt;</mo><mn>3</mn><mi>σ</mi></math></span> for any of these templates at any location within <span><math><msub><mrow><mi>R</mi></mrow><mrow><mn>200</mn></mrow></msub></math></span> of the cluster center. We obtain 95% C.L. upper limit on the energy flux ranging between <span><math><mo>∼</mo><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>6</mn></mrow></msup></math></span> and <span><math><msup><mrow><mn>10</mn></mrow><mrow><mo>−</mo><mn>4</mn></mrow></msup><mspace></mspace><mtext>MeV</mtext><mspace></mspace><msup><mrow><mtext>cm</mtext></mrow><mrow><mo>−</mo><mn>2</mn></mrow></msup><mspace></mspace><msup><mrow><mtext>s</mtext></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></math></span> depending on the energy range. These upper limits are consistent with a previously reported non-zero flux detected by Fermi-LAT at 6<em>σ</em> significance. This work represents the first proof of principle search for gamma-ray emission from a single galaxy cluster using DAMPE data.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"44 ","pages":"Pages 210-213"},"PeriodicalIF":10.2,"publicationDate":"2024-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142422642","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Observational analysis of late-time acceleration in f(Q,Lm) gravity","authors":"Kairat Myrzakulov ,&nbsp;M. Koussour ,&nbsp;O. Donmez ,&nbsp;A. Cilli ,&nbsp;E. Güdekli ,&nbsp;J. Rayimbaev","doi":"10.1016/j.jheap.2024.09.014","DOIUrl":"10.1016/j.jheap.2024.09.014","url":null,"abstract":"&lt;div&gt;&lt;div&gt;In this study, we explored late-time cosmology within an extended class of theories based on &lt;span&gt;&lt;math&gt;&lt;mi&gt;f&lt;/mi&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mi&gt;Q&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;L&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/math&gt;&lt;/span&gt; gravity. This theory generalizes &lt;span&gt;&lt;math&gt;&lt;mi&gt;f&lt;/mi&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mi&gt;Q&lt;/mi&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/math&gt;&lt;/span&gt; gravity by incorporating a non-minimal coupling between the non-metricity &lt;em&gt;Q&lt;/em&gt; and the matter Lagrangian &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;L&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;, analogous to the &lt;span&gt;&lt;math&gt;&lt;mi&gt;f&lt;/mi&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mi&gt;Q&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mi&gt;T&lt;/mi&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/math&gt;&lt;/span&gt; theory. The coupling between &lt;em&gt;Q&lt;/em&gt; and &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;L&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; leads to the non-conservation of the matter energy-momentum tensor. We first investigated a cosmological model defined by the functional form &lt;span&gt;&lt;math&gt;&lt;mi&gt;f&lt;/mi&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mi&gt;Q&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;L&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mi&gt;α&lt;/mi&gt;&lt;mi&gt;Q&lt;/mi&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;mi&gt;β&lt;/mi&gt;&lt;msubsup&gt;&lt;mrow&gt;&lt;mi&gt;L&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;n&lt;/mi&gt;&lt;/mrow&gt;&lt;/msubsup&gt;&lt;/math&gt;&lt;/span&gt;, where &lt;em&gt;α&lt;/em&gt;, &lt;em&gt;β&lt;/em&gt;, and &lt;em&gt;n&lt;/em&gt; are constants. The derived Hubble parameter &lt;span&gt;&lt;math&gt;&lt;mi&gt;H&lt;/mi&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mi&gt;z&lt;/mi&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;H&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;mi&gt;z&lt;/mi&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mfrac&gt;&lt;mrow&gt;&lt;mn&gt;3&lt;/mn&gt;&lt;mi&gt;n&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;mi&gt;n&lt;/mi&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/mrow&gt;&lt;/mfrac&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/math&gt;&lt;/span&gt; indicates that &lt;em&gt;n&lt;/em&gt; significantly influences the scaling of &lt;span&gt;&lt;math&gt;&lt;mi&gt;H&lt;/mi&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mi&gt;z&lt;/mi&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/math&gt;&lt;/span&gt; over cosmic history, with &lt;span&gt;&lt;math&gt;&lt;mi&gt;n&lt;/mi&gt;&lt;mo&gt;&gt;&lt;/mo&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/math&gt;&lt;/span&gt; suggesting accelerated expansion. We also examined the simplified case of &lt;span&gt;&lt;math&gt;&lt;mi&gt;n&lt;/mi&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;1&lt;/mn&gt;&lt;/math&gt;&lt;/span&gt;, leading to the linear form &lt;span&gt;&lt;math&gt;&lt;mi&gt;f&lt;/mi&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mi&gt;Q&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;L&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mi&gt;α&lt;/mi&gt;&lt;mi&gt;Q&lt;/mi&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;mi&gt;β&lt;/mi&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;L&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;, consistent with a universe dominated by non-relativistic matter. Using various observational datasets, including &lt;span&gt;&lt;math&gt;&lt;mi&gt;H&lt;/mi&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mi&gt;z&lt;/mi&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/math&gt;&lt;/span&gt; and Pantheon, we constrained the model parameters. Our analysis showed that the &lt;span&gt;&lt;math&gt;&lt;mi&gt;f&lt;/mi&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mi&gt;Q&lt;/mi&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;L&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;m&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;/math&gt;&lt;/span&gt; model aligns well with observational results and exhibits similar behavior to the ΛCDM model. The results, with &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;q&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;0&lt;/mn&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;0.22&lt;/mn&gt;&lt;mo&gt;±&lt;/mo&gt;&lt;mn&gt;0.01&lt;/mn&gt;&lt;/math&gt;&lt;/span&gt; across all datasets, indicate an accelerating universe, highlighting the model's potential as","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"44 ","pages":"Pages 164-171"},"PeriodicalIF":10.2,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142422643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of the drift of the South Atlantic Anomaly using particle monitors onboard Insight-HXMT","authors":"Hai-Sheng Zhao ,&nbsp;Shi-Jie Zheng ,&nbsp;Liu-Yuan Li ,&nbsp;Ming-Yu Ge ,&nbsp;Shuang-Nan Zhang ,&nbsp;Shu Zhang ,&nbsp;Shao-Lin Xiong ,&nbsp;Li-Ming Song","doi":"10.1016/j.jheap.2024.09.013","DOIUrl":"10.1016/j.jheap.2024.09.013","url":null,"abstract":"<div><div>Using the particle monitors aboard <span><math><mi>I</mi><mi>n</mi><mi>s</mi><mi>i</mi><mi>g</mi><mi>h</mi><mi>t</mi></math></span>-HXMT satellite, we analyzed over 6.5 years of continuous data to study the South Atlantic Anomaly (SAA) position, average count rate, and surface size, as well as its evolution from June 2017 to March 2024. We confirm the anti-correlation between the particle count rate obtained by particle monitors and the solar activity, as well as the anti-correlation between the evolution of the SAA surface size and the solar activity. Furthermore, this study confirms earlier measurements of a westward drift of the SAA with a rate of <span><math><mn>0.343</mn><mo>±</mo><msup><mrow><mn>0.002</mn></mrow><mrow><mi>o</mi></mrow></msup></math></span>/yr in longitude. However, it reveals a smaller northward drift with a rate of <span><math><mn>0.028</mn><mo>±</mo><msup><mrow><mn>0.002</mn></mrow><mrow><mi>o</mi></mrow></msup></math></span>/yr in latitude. Two irregular drifts both in longitude and latitude were observed. We suggest that the irregular drifts may be not driven by solar cycle variation of the atmosphere but may be associated with geomagnetic jerks.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"44 ","pages":"Pages 187-193"},"PeriodicalIF":10.2,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142422648","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Role of decoupling process on the configurations of compact stars induced by Thomas-Fermi dark matter with null complexity in f(T) gravity","authors":"S.K. Maurya ,&nbsp;Jitendra Kumar ,&nbsp;Sweeti Kiroriwal","doi":"10.1016/j.jheap.2024.09.012","DOIUrl":"10.1016/j.jheap.2024.09.012","url":null,"abstract":"<div><div>Our goal in this work is to find an anisotropic solution for a self-bound compact object composed of dark matter with a null complexity factor in <span><math><mi>f</mi><mo>(</mo><mi>T</mi><mo>)</mo></math></span>-gravity theory. We use a well-known gravitational decoupling via complete geometric deformation (CGD) technique to examine the role of decoupling parameters on the configuration of compact objects. Initially, we derive the null complexity condition for <span><math><mi>f</mi><mo>(</mo><mi>T</mi><mo>)</mo></math></span>-gravity decoupled system which leads to a relation between gravitational potentials. Next, we apply the CGD approach to split the decoupled system into two subsystems. The initial system refers to a pure <span><math><mi>f</mi><mo>(</mo><mi>T</mi><mo>)</mo></math></span> gravity system consisting of an isotropic fluid distribution, where the isotropy criterion is equivalent to the condition in Einstein's gravity. The solution of the first system is solved through the Vlasenk-Pronin space-time metrics while the second system associated with the deformation function is solved by the density constraints method by mimicking a new source with Thomas-Fermi dark matter density profile that generates the anisotropy in the decoupled system. The physical validity of the anisotropic solution is checked by the graphical analysis of the pressure, density, energy, and stability conditions. We have also shown the effect of torsion and decoupling parameters on the configuration of anisotropic compact objects. The energy exchange (Δ<em>E</em>) of fluid distribution is also discussed. We found that Δ<em>E</em> is positive throughout the stellar configuration, which implies that energy is effectively transmitted to the surrounding environment.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"44 ","pages":"Pages 194-209"},"PeriodicalIF":10.2,"publicationDate":"2024-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142422645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}