Journal of High Energy Astrophysics最新文献

{"title":"Insights into the long-term behavior of the optical polarization from the blazar 1ES 1959+650","authors":"K.K. Singh ,&nbsp;A. Singh ,&nbsp;A. Tolamatti ,&nbsp;P.J. Meintjes ,&nbsp;K.K. Yadav","doi":"10.1016/j.jheap.2025.100361","DOIUrl":"10.1016/j.jheap.2025.100361","url":null,"abstract":"<div><div>A high degree of linear polarization measured in the optical emission is an important observational feature of blazars. It provides strong evidence of the presence of relativistic particles and magnetic field ordering in the non-thermal emission regions of blazars owing to the synchrotron nature of low energy radiation. Thus, the polarization studies of blazars are emerging as a promising approach to probe the particle acceleration and the physical processes involved in their broadband emission. In this work, we investigate the behavior of the optical polarization of the blazar 1ES 1959+650 measured over a decade using the spectropolarimetry (SPOL) at the Steward Observatory. We use measurements of the degree of linear polarization and angle of polarization in the wavelength range 500 - 700 nm available during the period October 1, 2008 and June 30, 2018 (MJD 54739 - 58299) from the SPOL observations. Near simultaneous photometry data in the R and V bands are also used to study the optical emission from the source. The maximum degree of linear polarization, measured as ∼ 8.5%, is significantly larger than the long term average value of ∼ 4.6%. Analysis of the light curves indicates that the optical emission from the blazar 1ES 1959+650 is highly variable and variability in the degree of linear polarization can be quantified by a fractional variability amplitude of ∼ 39% over the period of about ten years. Long term optical emission in the R and V bands is very weakly anti-correlated with the degree of linear polarization. Modeling of the polarization due to the synchrotron emission suggests that the observed degree of linear polarization can be broadly reproduced by a power law distribution of relativistic electrons gyrating in a spherical emission region permeated with chaotic and ordered magnetic fields. Variation in the measured degree of polarization may be attributed to the interplay between the two magnetic field components in the emission region. The effect of stellar emission from the host galaxy of the blazar 1ES 1959+650 on the degree of synchrotron polarization originating from the jet is also discussed.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"47 ","pages":"Article 100361"},"PeriodicalIF":10.2,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143552612","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":"Long pulse by short central engine: Prompt emission from expanding dissipation rings in the jet front of gamma-ray bursts","authors":"Shu-Xu Yi ,&nbsp;Emre Seyit Yorgancioglu ,&nbsp;S.-L. Xiong ,&nbsp;S.-N. Zhang","doi":"10.1016/j.jheap.2025.100359","DOIUrl":"10.1016/j.jheap.2025.100359","url":null,"abstract":"<div><div>Recent observations have challenged the long-held opinion that the duration of gamma-ray burst (GRB) prompt emission is determined by the activity epochs of the central engine. Specifically, the observations of GRB 230307A have revealed a different scenario in which the duration of the prompt emission is predominantly governed by the energy dissipation process following a brief initial energy injection from the central engine. In this paper, we explore a mechanism where the energy injection from the central engine initially causes turbulence in a small region and radiates locally. This turbulence then propagates to more distant regions and radiates. Consequently, the emission regions form concentric rings that extend outward. Using an idealized toy model, we show that such a mechanism, initiated by a pulsed energy injection, can produce a prompt emission light curve resembling a single broad pulse exhibiting the typical softer-wider/softer-later feature. Under some parameters, the main characteristics of the GRB 230307A spectra and light curves can be reproduced by the toy model.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"47 ","pages":"Article 100359"},"PeriodicalIF":10.2,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143552583","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":"Is the NANOGrav detection evidence of resonant particle creation during inflation?","authors":"M.R. Gangopadhyay ,&nbsp;V.V. Godithi ,&nbsp;R. Inui ,&nbsp;K. Ichiki ,&nbsp;T. Kajino ,&nbsp;A. Manusankar ,&nbsp;G.J. Mathews ,&nbsp;Yogesh","doi":"10.1016/j.jheap.2025.100358","DOIUrl":"10.1016/j.jheap.2025.100358","url":null,"abstract":"<div><div>We show that the recently reported cosmic gravitational wave background by the NANOGrav 15-year collaboration may be the result of resonant particle creation during inflation. For the appropriate amplitude and particle mass, an enhancement of the primordial scalar power spectrum could induce Secondary Induced Gravitational Waves (SIGW), which will appear on a scale corresponding to the frequency of the NANOGrav detection. Since the resonant creation will have an effect comparable to that of a delta function increment as studied by the NANOGrav 15-year collaboration, our study indicates that the low-frequency Pulsar Timing Array (PTA) data could reveal the aspects of the physics during inflation through the detection of a cosmic background of Gravitational Waves (GW).</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"47 ","pages":"Article 100358"},"PeriodicalIF":10.2,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143474254","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":"Szekeres universes with GUP corrections","authors":"Andronikos Paliathanasis","doi":"10.1016/j.jheap.2025.100357","DOIUrl":"10.1016/j.jheap.2025.100357","url":null,"abstract":"<div><div>We demonstrate that introducing a deformed algebra with a minimum length modifies the field equations for an inhomogeneous spacetime, resulting in the emergence of acceleration. Specifically, we examine the analytic effects of the Generalized Uncertainty Principle on the classical field equations of the Szekeres system. Our findings show that the deformed algebra leads to a modified Szekeres system capable of describing cosmic acceleration. Moreover, the spatial curvature of the spacetime is influenced by the presence of the minimum length.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"46 ","pages":"Article 100357"},"PeriodicalIF":10.2,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143445917","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":"Shadows of rotating hairy black holes surrounded with quintessence and constraints from EHT observations","authors":"Fazlay Ahmed ,&nbsp;Shafqat Ul Islam ,&nbsp;Sushant G. Ghosh","doi":"10.1016/j.jheap.2025.100350","DOIUrl":"10.1016/j.jheap.2025.100350","url":null,"abstract":"&lt;div&gt;&lt;div&gt;The Event Horizon Telescope (EHT) collaboration recently unveiled the first image of the supermassive black hole M87*, which exhibited a ring of angular diameter &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;θ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;d&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;42&lt;/mn&gt;&lt;mo&gt;±&lt;/mo&gt;&lt;mn&gt;3&lt;/mn&gt;&lt;mi&gt;μ&lt;/mi&gt;&lt;mi&gt;a&lt;/mi&gt;&lt;mi&gt;s&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt;, a circularity deviation &lt;span&gt;&lt;math&gt;&lt;mi&gt;Δ&lt;/mi&gt;&lt;mi&gt;C&lt;/mi&gt;&lt;mo&gt;≤&lt;/mo&gt;&lt;mn&gt;0.1&lt;/mn&gt;&lt;/math&gt;&lt;/span&gt;, and also inferred a black hole mass of &lt;span&gt;&lt;math&gt;&lt;mi&gt;M&lt;/mi&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mo&gt;(&lt;/mo&gt;&lt;mn&gt;6.5&lt;/mn&gt;&lt;mo&gt;±&lt;/mo&gt;&lt;mn&gt;0.7&lt;/mn&gt;&lt;mo&gt;)&lt;/mo&gt;&lt;mo&gt;×&lt;/mo&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mn&gt;10&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;9&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;M&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;⊙&lt;/mo&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;. The shadow of Sgr A&lt;sup&gt;⁎&lt;/sup&gt; has an angular diameter &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;θ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;d&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;48.7&lt;/mn&gt;&lt;mo&gt;±&lt;/mo&gt;&lt;mn&gt;7&lt;/mn&gt;&lt;mspace&gt;&lt;/mspace&gt;&lt;mi&gt;μ&lt;/mi&gt;&lt;/math&gt;&lt;/span&gt;as with fractional deviation from the Schwarzschild black hole shadow diameter &lt;span&gt;&lt;math&gt;&lt;mi&gt;δ&lt;/mi&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;msubsup&gt;&lt;mrow&gt;&lt;mn&gt;0.08&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;0.09&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;mn&gt;0.09&lt;/mn&gt;&lt;/mrow&gt;&lt;/msubsup&gt;&lt;mspace&gt;&lt;/mspace&gt;&lt;mo&gt;,&lt;/mo&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;msubsup&gt;&lt;mrow&gt;&lt;mn&gt;0.04&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;0.10&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;+&lt;/mo&gt;&lt;mn&gt;0.09&lt;/mn&gt;&lt;/mrow&gt;&lt;/msubsup&gt;&lt;/math&gt;&lt;/span&gt; (for the VLTI and Keck mass-to-distance ratios). The image of the supermassive black holes M87* and SgrA* opened new avenues for testing gravitational theories in extreme regimes. While current observations align with the Kerr black hole model, they cannot conclusively support or reject any specific black hole model. Motivated by this, we use the gravitational decoupling approach to derive an exact rotating hairy Kiselev black hole solution, which incorporates the effects of a quintessence parameter &lt;em&gt;ω&lt;/em&gt; and a hairy parameter &lt;em&gt;l&lt;/em&gt;. Using this solution, we investigate the shadows of rotating hairy black holes surrounded by quintessence, focusing on constraints derived from EHT observations. We explore the effects of quintessence and hairy parameters on the shadows of rotating Kiselev black holes, analyzing how these parameters deviate from the Kerr geometry and influence the black hole's horizon structure, geodesics, and shadow morphology. Our study reveals that the shadow radius, distortion, and other observables are significantly affected by the quintessence state parameter &lt;em&gt;ω&lt;/em&gt;, the hairy parameter &lt;em&gt;l&lt;/em&gt;, and the spin parameter &lt;em&gt;a&lt;/em&gt;. Through a detailed analysis of the shadow's behavior, including the impact of observer inclination and the parameter space constraints, we derived bounds on these parameters consistent with EHT observations of M87* and SgrA*. We calculate the circularity deviation, angular diameter, and Schwarzschild deviation, showing that while the current EHT data cannot distinguish between the shadows of hairy Kiselev and standard Kerr black holes, future observations, such as those from ngEHT, may provide more p","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"46 ","pages":"Article 100350"},"PeriodicalIF":10.2,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143402620","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 M87⁎ and SgrA⁎ observational constraints of Dunkl black holes","authors":"N. Askour ,&nbsp;A. Belhaj ,&nbsp;L. Chakhchi ,&nbsp;H. El Moumni ,&nbsp;K. Masmar","doi":"10.1016/j.jheap.2025.100349","DOIUrl":"10.1016/j.jheap.2025.100349","url":null,"abstract":"<div><div>In this work, we investigate the optical properties of a new black hole being recently obtained from the Dunkl operator formalism involving a relevant parameter denoted by <em>ζ</em>. Concretely, we show that the reflections associated with the Dunkl operators can influence the optical properties of black holes. To do so, we first investigate the shadows, the Lyapunov exponents of unstable nearly bound orbits, and the spherically infalling accretion behaviors in terms of such a parameter. Then, we examine the effect of this parameter on the Dunkl black hole deflection angle in vacuum and medium backgrounds by manipulating the Gauss-Bonnet theorem. Exploiting the M87^⋆ and SgrA^⋆ optical bonds, we provide strong constraints on <em>ζ</em> via the falsification mechanism.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"46 ","pages":"Article 100349"},"PeriodicalIF":10.2,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143387316","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":"Dark energy constraints using gamma-ray burst correlations with DESI 2024 data","authors":"Anna Chiara Alfano ,&nbsp;Orlando Luongo ,&nbsp;Marco Muccino","doi":"10.1016/j.jheap.2025.100348","DOIUrl":"10.1016/j.jheap.2025.100348","url":null,"abstract":"<div><div>Even though the Dark Energy Spectroscopic Instrument (DESI) mission does not exclude a dynamical dark energy evolution, the concordance paradigm, i.e., the ΛCDM model, remains statistically favored, as it depends on the fewest number of free parameters. In this respect, high redshift astrophysical sources, such as gamma-ray bursts, represent a formidable tool to model the form of dark energy, since they may provide a link between early and local redshift regimes. Hence, the use of these objects as possible distance indicators turns out to be essential to investigate the cosmological puzzle. To this end, we adopt two gamma-ray burst linear correlations, namely the <span><math><msub><mrow><mi>L</mi></mrow><mrow><mi>p</mi></mrow></msub><mo>−</mo><msub><mrow><mi>E</mi></mrow><mrow><mi>p</mi></mrow></msub></math></span> and <span><math><msub><mrow><mi>L</mi></mrow><mrow><mn>0</mn></mrow></msub><mo>−</mo><msub><mrow><mi>E</mi></mrow><mrow><mi>p</mi></mrow></msub><mo>−</mo><mi>T</mi></math></span> relations, to test the flat and non-flat ΛCDM, <span><math><msub><mrow><mi>ω</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span>CDM, and <span><math><msub><mrow><mi>ω</mi></mrow><mrow><mn>0</mn></mrow></msub><msub><mrow><mi>ω</mi></mrow><mrow><mn>1</mn></mrow></msub></math></span>CDM cosmological models, i.e., those directly examined by the DESI collaboration. The inferred correlation coefficients and cosmological parameters are thus obtained by considering two independent Monte Carlo Markov chain analyses, the first considering the whole DESI data set and the second excluding a seemingly problematic data point placed at <span><math><msub><mrow><mi>z</mi></mrow><mrow><mi>e</mi><mi>f</mi><mi>f</mi></mrow></msub><mo>=</mo><mn>0.51</mn></math></span>. Using model selection criteria, the two above correlations do not show a preference on a precise cosmological model although, when the data point at <span><math><msub><mrow><mi>z</mi></mrow><mrow><mi>e</mi><mi>f</mi><mi>f</mi></mrow></msub></math></span> is included, the concordance paradigm appears to be the least favored among the tested cosmological models.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"46 ","pages":"Article 100348"},"PeriodicalIF":10.2,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143377890","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":"Modified Compton effect and CMB anisotropy","authors":"S. Davood Sadatian ,&nbsp;Amir Sabouri ,&nbsp;Zahra Davari","doi":"10.1016/j.jheap.2025.100347","DOIUrl":"10.1016/j.jheap.2025.100347","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Recent satellite observations have revealed significant anisotropy in the cosmic microwave background (CMB) radiation, a phenomenon that had previously been detected but received limited attention due to its subtlety. With the advent of more precise measurements from satellites, the extent of this anisotropy has become increasingly apparent. This paper examines the CMB radiation by reviewing past research on the causes of CMB anisotropy and presents a new model (Modified-ΛCDM) to explain the observed temperature anisotropy and the anisotropy in the correlation function between temperature and E-mode polarization in the CMB radiation. The proposed model is based on a modified-generalized Compton scattering approach incorporating Loop Quantum Gravity (LQG). We begin by describing the generalized Compton scattering and then discuss the CMB radiation in the context of processes occurring at the last scattering surface. Our findings are derived from the latest observational data from the Planck satellite (2018) and recent Dark Energy Survey Instrument (DESI) baryon acoustic oscillation (BAO). In our model, besides the parameters available in the Planck data for the standard model (ΛCDM), we introduce two novel parameters: &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;δ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;L&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;, the density of cosmic electrons, and &lt;span&gt;&lt;math&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mi&gt;M&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/math&gt;&lt;/span&gt;, a parameter related to the modified-generalized Compton scattering effects. Utilizing Planck 2018 data (TTTEEE+lowE+lowT+lensing), the Modified-ΛCDM model estimates the best-fit values of &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;δ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;L&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;0.161&lt;/mn&gt;&lt;mo&gt;×&lt;/mo&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mn&gt;10&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;9&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/math&gt;&lt;/span&gt; and &lt;span&gt;&lt;math&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mi&gt;M&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;0.006&lt;/mn&gt;&lt;/math&gt;&lt;/span&gt;. A combined analysis incorporating Planck 2018, PantheonPlus sample and DESI BAO datasets yields &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;δ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;L&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;0.184&lt;/mn&gt;&lt;mo&gt;×&lt;/mo&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mn&gt;10&lt;/mn&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mo&gt;−&lt;/mo&gt;&lt;mn&gt;9&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/math&gt;&lt;/span&gt; and &lt;span&gt;&lt;math&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mi&gt;M&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;mo&gt;=&lt;/mo&gt;&lt;mn&gt;0.023&lt;/mn&gt;&lt;/math&gt;&lt;/span&gt;, demonstrating consistency between these datasets and first analyze using CMB. Increasing the values of &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mrow&gt;&lt;mi&gt;δ&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mi&gt;L&lt;/mi&gt;&lt;/mrow&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; and &lt;span&gt;&lt;math&gt;&lt;msup&gt;&lt;mrow&gt;&lt;mi&gt;M&lt;/mi&gt;&lt;/mrow&gt;&lt;mrow&gt;&lt;mn&gt;2&lt;/mn&gt;&lt;/mrow&gt;&lt;/msup&gt;&lt;/math&gt;&lt;/span&gt; amplifies temperature anisotropy power spectrum fluctuations and temperature-E-mode correlation for multipoles &lt;span&gt;&lt;math&gt;&lt;mn&gt;100&lt;/mn&gt;&lt;mo&gt;&lt;&lt;/mo&gt;&lt;mi&gt;l&lt;/mi&gt;&lt;mo&gt;&lt;&lt;/mo&gt;&lt;mn&gt;500&lt;/mn&gt;&lt;/math&gt;&lt;/span&gt;, particularly near the first peak. Statistical analysis further highlights these effects, emphasizing the importance of modified Compton scattering on the integrated Sachs","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"46 ","pages":"Article 100347"},"PeriodicalIF":10.2,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143353714","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":"Thermal instability of thin disk in the presence of wind and corona","authors":"Arezoo Tajmohamadi ,&nbsp;Shahram Abbassi","doi":"10.1016/j.jheap.2025.01.018","DOIUrl":"10.1016/j.jheap.2025.01.018","url":null,"abstract":"<div><div>This study investigates the thermal stability of thin accretion disks in high-energy astrophysical systems, incorporating the effects of magnetic fields, winds, and coronae. We analyze how these factors influence disk stability, focusing on conditions under which magnetic fields enhance stability and on scenarios where winds and coronae can either stabilize or destabilize the disk. Our results reveal that increasing corona parameters raises disk thickness and reduces temperature, thereby affecting gas, radiation, and magnetic pressures. These interactions underscore the complex dependencies that shape accretion disk dynamics, offering insights into their structural and thermal behavior under varying physical conditions. The findings contribute to advancing theoretical models and numerical simulations of accretion processes in environments such as active galactic nuclei (AGN) and X-ray binaries, where disk stability plays a critical role in observed emissions and variability patterns.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"46 ","pages":"Article 100346"},"PeriodicalIF":10.2,"publicationDate":"2025-01-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143175922","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":"Shadow images of Ghosh-Kumar rotating black hole illuminated by spherical light sources and thin accretion disks","authors":"Chen-Yu Yang ,&nbsp;M. Israr Aslam ,&nbsp;Xiao-Xiong Zeng ,&nbsp;Rabia Saleem","doi":"10.1016/j.jheap.2025.01.017","DOIUrl":"10.1016/j.jheap.2025.01.017","url":null,"abstract":"<div><div>This study investigates the astronomical implications of the Ghosh-Kumar rotating Black Hole (BH), particularly its behaviour on shadow images, illuminated by celestial light sources and equatorial thin accretion disks. Our research delineates a crucial correlation between dynamics of the shadow images and the parameters <em>a</em>, <em>q</em> and the <span><math><msub><mrow><mi>θ</mi></mrow><mrow><mi>o</mi><mi>b</mi><mi>s</mi></mrow></msub></math></span>, which aptly reflect the influence of the model parameters on the optical features of shadow images. Initially, elevated behaviour of both <em>a</em> and <em>q</em> transforms the geometry of the shadow images from perfect circles to an oval shape and converges them towards the centre of the screen. By imposing the backward ray-tracing method, we demonstrate the optical appearance of shadow images of the considering BH space-time in the celestial light source. The results demonstrate that the Einstein ring shows a transition from an axisymmetric closed circle to an arc-like shape on the screen as well as producing the deformation on the shadow shape with the modifications of space-time parameters at the fixed observational position. Next, we observe that the attributes of accretion disks along with the relevant parameters on the shadow images are illuminated by both prograde and retrograde accreting flow. Our study reveals the process by which the accretion disk transitions from a disk-like structure to a hat-like shape with the aid of observational angles. Moreover, with an increase of <em>q</em>, the observed flux of both direct and lensed images of the accretion disk gradually moves towards the lower zone of the screen. Furthermore, we present the intensity distribution of the red-shift factors on the screen. Our analysis suggests that the observer can see both red-shift and blue-shift factors on the screen at higher observational angles, while augmenting the values of both <em>a</em> and <em>q</em>, enhancing the effect of red-shift on the screen.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"46 ","pages":"Article 100345"},"PeriodicalIF":10.2,"publicationDate":"2025-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143175921","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}