Journal of High Energy Astrophysics最新文献

{"title":"Detection of polarized Fermi-bubble synchrotron and dust emission","authors":"Uri Keshet","doi":"10.1016/j.jheap.2024.12.010","DOIUrl":"10.1016/j.jheap.2024.12.010","url":null,"abstract":"<div><div>The elusive polarized microwave signal from the Fermi bubbles is disentangled from the more extended polarized lobes, which similarly emanate from the Galactic plane but stretch farther west of the bubbles. The projected <span><math><mo>∼</mo><mn>20</mn><mtext>%</mtext></math></span> synchrotron polarization reveals magnetic fields preferentially parallel to the bubble edges, as expected downstream of a strong shock. The projected <span><math><mo>∼</mo><mn>20</mn><mtext>%</mtext></math></span> polarization of thermal dust emission is similarly oriented, constraining grain alignment in an extreme environment. We argue that the larger lobes arise from an older Galactic-center, likely supermassive black-hole, outburst.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"45 ","pages":"Pages 299-305"},"PeriodicalIF":10.2,"publicationDate":"2024-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143102792","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":"A doublet of cosmological models to challenge the H0 tension in the Pantheon Supernovae Ia catalog","authors":"B. De Simone ,&nbsp;M.H.P.M. van Putten ,&nbsp;M.G. Dainotti ,&nbsp;G. Lambiase","doi":"10.1016/j.jheap.2024.12.003","DOIUrl":"10.1016/j.jheap.2024.12.003","url":null,"abstract":"<div><div>ΛCDM provides a leading framework in the interpretation of modern cosmology. Nevertheless, the scientific community still struggles with many open problems in cosmology. Among the most noticeable ones, the tension in the Hubble constant <em>H</em>₀ is particularly intriguing, prompting a wide range of possible solutions. In the present work, the flat scale-free cosmology (<em>S</em> CDM) of Maeder (2017) is tested for <em>H</em>₀ tension in fits to the Pantheon sample of Supernovae Ia. The Pantheon sample is a collection of 1048 SNe Ia, which formally defines <em>H</em>₀ = <em>H</em>(0) by extrapolation to redshift zero of data over positive redshifts <em>z</em> &gt; 0. Here, we consider <em>H</em>_0,<em>_k</em> in fits of <em>S</em> CDM over <em>k</em> equally sized bins of sub-samples of mean redshift <em>z_k</em>. To quantify a trend in <em>H</em>_0,<em>_k</em> with <em>z_k</em>, the results are fit by <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>z</mi><mo>)</mo></mrow><mo>=</mo><msup><mrow><mrow><msubsup><mi>H</mi><mn>0</mn><mo>′</mo></msubsup><mo>/</mo><mrow><mo>(</mo><mrow><mn>1</mn><mo>+</mo><mi>z</mi></mrow><mo>)</mo></mrow></mrow></mrow><mi>α</mi></msup></mrow></math></span> in the two parameters <span><math><msubsup><mi>H</mi><mn>0</mn><mo>′</mo></msubsup></math></span> and α. This approach tests for model imperfections or data biases by trends that are inconsistent with zero. Our findings show a decreasing trend inconsistent with zero at 5.3σ significance, significantly more so than in ΛCDM. These results are further confirmed in Pantheon+. It appears that a solution to <em>H</em>₀ tension is to be found in models with a deceleration parameter <em>q</em>₀ &lt; <em>q</em>_0,Λ below that of ΛCDM, rather than <em>q</em>_0,Λ &lt; <em>q</em>_0,<em>_S</em> &lt; 0 satisfied by <em>S</em> CDM.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"45 ","pages":"Pages 290-298"},"PeriodicalIF":10.2,"publicationDate":"2024-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143102791","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantum Gravitational Atoms as New Matter: A chance of Hydrogen with Primordial Black Hole Nuclei?","authors":"Elio Quiroga Rodríguez","doi":"10.1016/j.jheap.2024.12.008","DOIUrl":"10.1016/j.jheap.2024.12.008","url":null,"abstract":"<div><div>In this study, the author examines the theoretical properties of a hypothetical hydrogen-like atom composed of a primordial black hole (PBH) nucleus, called <em>PBH<img>H protoatoms.</em></div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"45 ","pages":"Pages 262-264"},"PeriodicalIF":10.2,"publicationDate":"2024-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143102788","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":"Comprehensive spectro-temporal studies of GX 17+2 using AstroSat observations","authors":"Neal Titus Thomas,&nbsp;S. Lavanya,&nbsp;S.B. Gudennavar,&nbsp;S.G. Bubbly","doi":"10.1016/j.jheap.2024.12.007","DOIUrl":"10.1016/j.jheap.2024.12.007","url":null,"abstract":"<div><div>We performed a comprehensive spectro-temporal study of the Z-type neutron star low-mass X-ray binary GX 17+2 using long term data from the <em>AstroSat</em>/Soft X-ray Telescope (SXT) and Large Area X-ray Proportional Counter (LAXPC). The hardness–intensity diagrams (HIDs) of the source revealed a positive correlation between the hardness and intensity, characteristic of soft spectral state. Additionally, the LAXPC-20 HID showed the presence of secular shifts in both hardness and intensity. Time-averaged spectral modelling in the 0.7 − 30.0 keV energy range indicated that the spectra could be well fitted with the model combination: <span>constant</span> × <span>edge</span> × <span>edge</span> × <span>tbabs</span> × <span>thcomp</span> × <span>bbodyrad</span>. This analysis yielded a blackbody radius (<span><math><msub><mrow><mi>R</mi></mrow><mrow><mi>b</mi><mi>b</mi></mrow></msub></math></span>) of ∼59 km, photon index (Γ) of ∼2.84 and electron temperature (<span><math><mi>k</mi><msub><mrow><mi>T</mi></mrow><mrow><mi>e</mi></mrow></msub></math></span>) of ∼4.84 keV. Time-averaged temporal analysis revealed normal branch oscillations (NBOs) at ∼ 7 Hz in Observations 1 and 3, flaring branch oscillation (FBO) at ∼15 Hz in Observation 2, and horizontal branch oscillation (HBO) at ∼36 Hz in Observation 5. Flux resolved spectro-temporal analysis indicated that the source remained in the soft spectral state throughout all observations. A positive correlation was observed between <span><math><mi>k</mi><msub><mrow><mi>T</mi></mrow><mrow><mi>b</mi><mi>b</mi></mrow></msub></math></span>, <span><math><msub><mrow><mi>F</mi></mrow><mrow><mi>b</mi><mi>b</mi></mrow></msub></math></span> and <span><math><msub><mrow><mi>F</mi></mrow><mrow><mi>b</mi><mi>o</mi><mi>l</mi></mrow></msub></math></span>, whereas an anti-correlation was noted between <span><math><mi>k</mi><msub><mrow><mi>T</mi></mrow><mrow><mi>e</mi></mrow></msub></math></span> and <span><math><msub><mrow><mi>F</mi></mrow><mrow><mi>b</mi><mi>o</mi><mi>l</mi></mrow></msub></math></span>. The constant frequency of NBOs with an increase in <span><math><msub><mrow><mi>F</mi></mrow><mrow><mi>b</mi><mi>o</mi><mi>l</mi></mrow></msub></math></span> suggests that their origin lies in a region strongly influenced by the corona, as explained by the radiation-hydrodynamic model. The origin of FBOs may be attributed to the damped radiation-hydrodynamic mode of radial flow, while the origin of HBOs is supported by the beat-frequency model.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"45 ","pages":"Pages 250-261"},"PeriodicalIF":10.2,"publicationDate":"2024-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143102787","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":"Effect of baryon number density (n) on the maximum mass and stability of strange stars","authors":"Anusmita Nag,&nbsp;Debadri Bhattacharjee,&nbsp;Koushik Ballav Goswami,&nbsp;Pradip Kumar Chattopadhyay","doi":"10.1016/j.jheap.2024.12.005","DOIUrl":"10.1016/j.jheap.2024.12.005","url":null,"abstract":"<div><div>A new class of relativistic solutions of Einstein field equations for an anisotropic strange star admitting the Vaidya-Tikekar type metric potential in the framework of MIT bag model equation of state of the strange matter, <span><math><msub><mrow><mi>p</mi></mrow><mrow><mi>r</mi></mrow></msub><mo>=</mo><mfrac><mrow><mn>1</mn></mrow><mrow><mn>3</mn></mrow></mfrac><mo>(</mo><mi>ρ</mi><mo>−</mo><mn>4</mn><mi>B</mi><mo>)</mo></math></span>, where <em>B</em> is termed as bag constant, is presented. In order to integrate the quark core hypothesis and provide an explanation for a physically feasible stellar model, we have examined the baryon number dependent <em>B</em> (<em>n</em>) via an extreme Wood-Saxon, like parameterisation. The energy per baryon <span><math><mo>(</mo><msub><mrow><mi>E</mi></mrow><mrow><mi>B</mi></mrow></msub><mo>)</mo></math></span> has been calculated to restrict <em>B</em> (<em>n</em>) within the stable window, i.e., <span><math><msub><mrow><mi>E</mi></mrow><mrow><mi>B</mi></mrow></msub><mo>&lt;</mo><mn>930.4</mn><mspace></mspace><mi>M</mi><mi>e</mi><mi>V</mi></math></span> <span><math><mo>(</mo><mmultiscripts><mrow><mi>F</mi></mrow><mprescripts></mprescripts><none></none><mrow><mn>56</mn></mrow></mmultiscripts><mi>e</mi><mo>)</mo></math></span>. This study investigates the baryon number density (<em>n</em>) induced phase transition between hadrons and quarks inside a stellar configuration. Interestingly, the nature of the variation of <span><math><msub><mrow><mi>E</mi></mrow><mrow><mi>B</mi></mrow></msub></math></span> vs. <em>n</em>, shows that for <span><math><mi>n</mi><mo>≥</mo><mn>1.1</mn><mspace></mspace><mi>f</mi><msup><mrow><mi>m</mi></mrow><mrow><mo>−</mo><mn>3</mn></mrow></msup></math></span> the energy per baryon approaches a constant value. We choose <span><math><mi>n</mi><mo>=</mo><mn>0.6</mn><mspace></mspace><mi>f</mi><msup><mrow><mi>m</mi></mrow><mrow><mo>−</mo><mn>3</mn></mrow></msup></math></span>, <span><math><mi>B</mi><mo>=</mo><mn>66.32</mn><mspace></mspace><mi>M</mi><mi>e</mi><mi>V</mi><mo>/</mo><mi>f</mi><msup><mrow><mi>m</mi></mrow><mrow><mn>3</mn></mrow></msup></math></span> within the stipulated restrictions and consider 4U 1608-52 as a strange star candidate. We find that all the characteristic properties are well satisfied within the stellar interior for the choice of parameters. The numerical solution of the TOV equations yields a maximum mass of strange quark stars of <span><math><mn>2.01</mn><mspace></mspace><msub><mrow><mi>M</mi></mrow><mrow><mo>⊙</mo></mrow></msub></math></span> and a corresponding radius of <span><math><mn>10.96</mn><mspace></mspace><mi>K</mi><mi>m</mi></math></span>. Proposed model meets the necessary energy conditions and also stability criteria, confirming its viability as a realistic stellar model within the parameter space used.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"45 ","pages":"Pages 231-240"},"PeriodicalIF":10.2,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143102785","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 very high energy gamma-ray emission from a sample of high redshift blazars with MACE","authors":"A. Tolamatti ,&nbsp;A. Garg ,&nbsp;A. Pathania ,&nbsp;K.K. Singh ,&nbsp;C. Borwankar ,&nbsp;M. Khurana ,&nbsp;P. Chandra ,&nbsp;A. Shukla ,&nbsp;S. Godiyal ,&nbsp;S. Godambe ,&nbsp;J. Hariharan ,&nbsp;Keshavanand ,&nbsp;N. Mankuzhyil ,&nbsp;S. Norlha ,&nbsp;P. Pandey ,&nbsp;D. Sarkar ,&nbsp;R. Thubstan ,&nbsp;K. Venugopal ,&nbsp;Z.A. Dar ,&nbsp;S.V. Kotwal ,&nbsp;K.K. Yadav","doi":"10.1016/j.jheap.2024.12.006","DOIUrl":"10.1016/j.jheap.2024.12.006","url":null,"abstract":"<div><div>Blazars, a subclass of face-on jetted active galactic nuclei, are the most persistent and powerful sources of cosmic gamma-rays in the Universe. They represent a dominant population of gamma-ray sources, spread all over the sky with known and unknown redshifts up to z ∼ 6 (e.g. <span><span>Belladitta et al. (2020)</span></span>). Detection of more than 3500 blazars by the space-based <em>Fermi</em>-Large Area Telescope (LAT) in the high energy (HE, above 100 MeV) band reveals that a significant amount of power carried by the relativistic plasma jets in blazars is dissipated at gamma-ray energies. However, a small fraction of only less than 3% are detected at very high energies (VHE, above 30 GeV) by the ground-based Cherenkov telescopes. Therefore, their detection at the highest possible energies is extremely important to understand the blazar-phenomenon in the Universe. In this paper, we report observational results obtained from the recent monitoring of the six high redshift (<span><math><mi>z</mi><mspace></mspace><mo>&gt;</mo><mspace></mspace><mn>0.3</mn></math></span>) blazars with the Major Atmospheric Cherenkov Experiment (MACE) in the energy range above ∼ 80 GeV. No statistically significant detection of the sources is found. Thus, for the null detections, we estimate 99% confidence level upper limit on the integral flux for the individual sources and use the <em>Fermi</em>-LAT measurements to constrain their gamma-ray emission behavior.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"45 ","pages":"Pages 241-249"},"PeriodicalIF":10.2,"publicationDate":"2024-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143102786","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":"Accretion onto a charged black hole in consistent 4D Einstein-Gauss-Bonnet gravity","authors":"Kourosh Nozari,&nbsp;Sara Saghafi,&nbsp;Mohammad Hassani","doi":"10.1016/j.jheap.2024.12.004","DOIUrl":"10.1016/j.jheap.2024.12.004","url":null,"abstract":"<div><div>In astrophysics, accretion is the process by which a massive object acquires matter. The infall leads to the extraction of gravitational energy. Accretion onto dark compact objects such as black holes, neutron stars, and white dwarfs is a crucial process in astrophysics as it turns gravitational energy into radiation. The accretion process is an effective technique to investigate the properties of other theories of gravity by examining the behavior of their solutions with compact objects. In this paper, we investigate the behavior of test particles around a charged four-dimensional Einstein–Gauss–Bonnet (4<em>D</em> EGB) black hole in order to understand their innermost stable circular orbit (ISCO) and energy flux, differential luminosity, and temperature of the accretion disk. Then, we examine particle oscillations around a central object via applying restoring forces to treat perturbations. Next, we explore the accretion of perfect fluid onto a charged 4<em>D</em> EGB black hole. We develop analytical formulas for four-velocity and proper energy density of the accreting fluid. The EGB parameter and the charge affect properties of the test particles by decreasing their ISCO radius and also decreasing their energy flux. Increasing the EGB parameter and the charge, near the central source reduces both the energy density and the radial component of the infalling fluid's four-velocity.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"45 ","pages":"Pages 214-230"},"PeriodicalIF":10.2,"publicationDate":"2024-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143162958","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 Hubble expansion in a Big Bang quantum cosmology","authors":"Maurice H.P.M. van Putten","doi":"10.1016/j.jheap.2024.12.002","DOIUrl":"10.1016/j.jheap.2024.12.002","url":null,"abstract":"<div><div>The Hubble expansion of the Universe is considered in the classical limit of a Big Bang quantum cosmology. In an IR-consistent coupling to the bare cosmological constant, we infer a dark energy as a relic of the Big Bang by loss of time-translation invariance on a Hubble time-scale. This dark energy is identified with the trace <em>J</em> of the Schouten tensor permitting an analytic solution <span><math><mi>H</mi><mo>(</mo><mi>z</mi><mo>)</mo></math></span>. Anchored by the <em>Baryonic Accoustic Oscillations</em>, <em>J</em>CDM predicts a Hubble constant <span><math><msub><mrow><mi>H</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>=</mo><msqrt><mrow><mn>6</mn><mo>/</mo><mn>5</mn></mrow></msqrt><mspace></mspace><msubsup><mrow><mi>H</mi></mrow><mrow><mn>0</mn></mrow><mrow><mi>Λ</mi></mrow></msubsup></math></span> alleviating <span><math><msub><mrow><mi>H</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span>-tension between the Local Distance Ladder and <span><math><msubsup><mrow><mi>H</mi></mrow><mrow><mn>0</mn></mrow><mrow><mi>Λ</mi></mrow></msubsup></math></span> in ΛCDM, whose dark energy Λ is a constant. Emulated by <span><math><mi>w</mi><mo>(</mo><mi>a</mi><mo>)</mo><mi>Λ</mi></math></span>CDM, a CAMB analysis shows a <em>J</em>CDM fit to the <em>Planck</em> 2018 <span><math><msubsup><mrow><mi>C</mi></mrow><mrow><mi>l</mi></mrow><mrow><mi>T</mi><mi>T</mi></mrow></msubsup></math></span> power spectrum on par with ΛCDM with small positive curvature consistent with <em>Planck</em>-ΛCDM with no extra relativistic degrees of freedom. In late-time cosmology, <em>J</em>CDM is also consistent with the BAO recently measured by DESI. <em>J</em>CDM offers a novel framework to address <span><math><msub><mrow><mi>H</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span>-tension, predicting background quantities consistent with the uncertainties in BAO measurements and early-Universe observations. It predicts a deceleration parameter <span><math><msub><mrow><mi>q</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>≃</mo><mo>−</mo><mn>1</mn></math></span>, that may be tested with upcoming low-redshift galaxy surveys.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"45 ","pages":"Pages 194-199"},"PeriodicalIF":10.2,"publicationDate":"2024-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143098612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The interplay of WGC and WCCC via charged scalar field fluxes in the RPST framework","authors":"Mohammad Reza Alipour ,&nbsp;Jafar Sadeghi ,&nbsp;Saeed Noori Gashti ,&nbsp;Mohammad Ali S. Afshar","doi":"10.1016/j.jheap.2024.11.022","DOIUrl":"10.1016/j.jheap.2024.11.022","url":null,"abstract":"<div><div>In this paper, we investigate the weak cosmic censorship conjecture (WCCC) for the Reissner-Nordström (R-N) AdS black hole within the framework of restricted phase space thermodynamics (RPST). Additionally, we consider energy flux and the equivalence mass-energy principle to examine the weak gravity conjecture (WGC) alongside the weak cosmic censorship conjecture. The interaction of incoming and outgoing energy flux leads to changes in the black hole. We examine whether the second law of thermodynamics holds in this scenario. It is noted that, when absorption and superradiance reach equilibrium, and by using the thermodynamics of black holes in restricted phase space, if the black hole is in or near an extreme state with radiation and particle absorption, the weak cosmic censorship conjecture is upheld. Furthermore, by employing the equivalence mass-energy principle and second-order approximation near extremality, we find that when the black hole radiates and its central charge exceeds the scaled electric charge, the superradiance particles adhere to the weak gravity conjecture. This causes the black hole to move away from its extreme state. However, when particles that obey the weak gravity conjecture are attracted to a very small black hole, the black hole approaches its extremality state.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"45 ","pages":"Pages 160-167"},"PeriodicalIF":10.2,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143098607","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":"Some aspects of ModMax (A)dS black holes: Thermodynamics properties, heat engine, shadow, null geodesic and light trajectory","authors":"B. Eslam Panah ,&nbsp;N. Heidari","doi":"10.1016/j.jheap.2024.12.001","DOIUrl":"10.1016/j.jheap.2024.12.001","url":null,"abstract":"<div><div>In this paper, we focus on the extraction of electrically charged black holes in the presence of modified Maxwell nonlinear electrodynamics and the cosmological constant, known as ModMax-(A)dS black holes. These black holes are of particular interest due to the substantial influence of the nonlinear Maxwell field (ModMax) and the cosmological constant on their properties. After obtaining exact ModMax-(A)dS black hole solutions, we proceed to study their thermodynamic properties, including conserved and thermodynamic quantities, as well as the first law of thermodynamics in a non-extended phase space. The local and global stabilities of these black holes are then assessed. Local stability is evaluated by examining the heat capacity while determining global stability involves calculating the Helmholtz free energy. Then, we investigate the heat engine of ModMax (A)dS black holes, considering the effects of the ModMax parameter and the cosmological constant on all quantities. Moreover, we explore the imprint of ModMax (A)dS black hole parameters on the critical orbits and shadow radius size, the results are compared with EHT observational data of the Sagittarius A^⁎ black holes. Lastly, the null geodesics and light trajectory are discussed in the presence of the ModMax theory.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"45 ","pages":"Pages 181-193"},"PeriodicalIF":10.2,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143098611","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}