Pub Date : 2025-12-23DOI: 10.1016/j.jheap.2025.100537
Guoying Zhao , Weikang Zheng , Rong-Feng Shen , Qingcang Shui , Dongyue Li , Chang Zhou , Tianci Zheng , Weimin Yuan , HeYang Liu , Junfeng Wang , Alexei V. Filippenko , Thomas G. Brink , Chong Ge , Jordan Forman , Mayra Gutierrez , Isabelle Jones , Ravjit Kaur , Naunet Leonhardes-Barboza , Petra Mengistu , Avi Patel , Michele N. Woodland
Stellar flares are an intense stellar activity that can significantly impact the atmospheric composition of the surrounding planets and even the possible existence of life. During such events, the radiative energy of the star is primarily concentrated in the optical and X-ray bands, with the X-ray flux potentially increasing by tens or even hundreds of times. Einstein Probe (EP) detected a new X-ray transient EP J2322.1–0301 on 27 September 2024. Its spatial localization shows a high positional coincidence with the nearby high proper motion K-type star PM J23221–0301. Follow-up X-ray observations confirmed the flux enhancement of the source, while optical spectroscopic monitoring revealed time-variable features, particularly the disappearance of the Hα emission line. This X-ray flare is consistent with a characteristic fast-rise-exponential-decay (FRED) light curve, with a rise timescale of 1.4 ks, a decay timescale of 5.7 ks, and a total duration of ∼ 7.1 ks. The peak luminosity in the 0.5–4.0 keV energy band reached ∼ 1.3 × 1031 erg s, with a total energy release of ∼ 9.1 × 1034 erg, consistent with the empirical energy correlations observed in magnetic-reconnection-driven stellar flares, as inferred from the multitemperature plasma structure and Hα-X-ray energy correlation. This discovery underscores EP’s capability in understanding stellar magnetic activity via observing stellar transients.
{"title":"Einstein Probe discovery of an X-ray flare from K-type star PM J23221-0301","authors":"Guoying Zhao , Weikang Zheng , Rong-Feng Shen , Qingcang Shui , Dongyue Li , Chang Zhou , Tianci Zheng , Weimin Yuan , HeYang Liu , Junfeng Wang , Alexei V. Filippenko , Thomas G. Brink , Chong Ge , Jordan Forman , Mayra Gutierrez , Isabelle Jones , Ravjit Kaur , Naunet Leonhardes-Barboza , Petra Mengistu , Avi Patel , Michele N. Woodland","doi":"10.1016/j.jheap.2025.100537","DOIUrl":"10.1016/j.jheap.2025.100537","url":null,"abstract":"<div><div>Stellar flares are an intense stellar activity that can significantly impact the atmospheric composition of the surrounding planets and even the possible existence of life. During such events, the radiative energy of the star is primarily concentrated in the optical and X-ray bands, with the X-ray flux potentially increasing by tens or even hundreds of times. Einstein Probe (EP) detected a new X-ray transient EP J2322.1–0301 on 27 September 2024. Its spatial localization shows a high positional coincidence with the nearby high proper motion K-type star PM J23221–0301. Follow-up X-ray observations confirmed the flux enhancement of the source, while optical spectroscopic monitoring revealed time-variable features, particularly the disappearance of the H<em>α</em> emission line. This X-ray flare is consistent with a characteristic fast-rise-exponential-decay (FRED) light curve, with a rise timescale of 1.4 ks, a decay timescale of 5.7 ks, and a total duration of ∼ 7.1 ks. The peak luminosity in the 0.5–4.0 keV energy band reached ∼ 1.3 × 10<sup>31</sup> erg s<span><math><msup><mrow></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></math></span>, with a total energy release of ∼ 9.1 × 10<sup>34</sup> erg, consistent with the empirical energy correlations observed in magnetic-reconnection-driven stellar flares, as inferred from the multitemperature plasma structure and H<em>α</em>-X-ray energy correlation. This discovery underscores EP’s capability in understanding stellar magnetic activity via observing stellar transients.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"51 ","pages":"Article 100537"},"PeriodicalIF":10.5,"publicationDate":"2025-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145938401","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}
We present a comprehensive study of the optical and dynamical properties of a rotating black hole immersed in a Dehnen-type (1,4,0) galactic dark matter halo, modelled by a double power-law density profile commonly used to describe realistic galactic cores. By extending our previous Schwarzschild-Dehnen solution using a modified Newman-Janis algorithm, we construct a Kerr-like axisymmetric spacetime that smoothly incorporates both black hole rotation and the influence of the surrounding dark matter halo. We systematically investigate the effects of the halo parameters-the central density and halo radius-on horizon structure, the shape and extent of the ergoregion, and the null geodesics associated with black hole shadows. Our results show that the presence of a dense or extended halo expands the event horizon and ergoregion, and significantly alters the size and distortion of the black hole shadow. Furthermore, by applying the WKB approximation to scalar field perturbations, we compute the quasinormal mode (QNM) spectra and demonstrate that the frequencies and damping times of ringdown signals are highly sensitive to the halo profile. These results open promising avenues for probing the dark matter environment of astrophysical black holes through black hole imaging and gravitational wave observations.
{"title":"Investigating optical and ring-down gravitational wave properties of a rotating black hole in a Dehnen galactic dark matter halo","authors":"Mrinnoy M. Gohain , Dhruba Jyoti Gogoi , Kalyan Bhuyan , Prabwal Phukon","doi":"10.1016/j.jheap.2025.100539","DOIUrl":"10.1016/j.jheap.2025.100539","url":null,"abstract":"<div><div>We present a comprehensive study of the optical and dynamical properties of a rotating black hole immersed in a Dehnen-type (1,4,0) galactic dark matter halo, modelled by a double power-law density profile commonly used to describe realistic galactic cores. By extending our previous Schwarzschild-Dehnen solution using a modified Newman-Janis algorithm, we construct a Kerr-like axisymmetric spacetime that smoothly incorporates both black hole rotation and the influence of the surrounding dark matter halo. We systematically investigate the effects of the halo parameters-the central density and halo radius-on horizon structure, the shape and extent of the ergoregion, and the null geodesics associated with black hole shadows. Our results show that the presence of a dense or extended halo expands the event horizon and ergoregion, and significantly alters the size and distortion of the black hole shadow. Furthermore, by applying the WKB approximation to scalar field perturbations, we compute the quasinormal mode (QNM) spectra and demonstrate that the frequencies and damping times of ringdown signals are highly sensitive to the halo profile. These results open promising avenues for probing the dark matter environment of astrophysical black holes through black hole imaging and gravitational wave observations.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"51 ","pages":"Article 100539"},"PeriodicalIF":10.5,"publicationDate":"2025-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145884292","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}
Pub Date : 2025-12-22DOI: 10.1016/j.jheap.2025.100538
Jose A. Carpio, Ali Kheirandish, Bing Zhang
Microquasars, compact binary systems with an accreting stellar-mass black hole or neutron star, are promising candidates for high-energy particle acceleration. Recently, the LHAASO collaboration reported on the detection of > 100 TeV γ-ray emission from five microquasars, suggesting that these sources are efficient particle accelerators. In microquasars, high-energy γ-rays can be produced in large-scale jets or winds. In this work, we explore the X-ray, γ-ray and neutrino emission from SS 433, V4641 Sgr and GRS 1905+105. We consider leptonic and hadronic scenarios to explain the spectra observed by LHAASO and other high-energy γ-ray detectors. We estimate the neutrino flux associated with the hadronic component and investigate the detectability of neutrinos from these sources in current and future neutrino telescopes. We find that among the three sources, V4641 Sgr has the best prospects of observation with a combined next-generation neutrino telescopes.
微类星体是一种紧凑的双星系统，有一个吸积的恒星质量黑洞或中子星，是高能粒子加速的有希望的候选者。最近，LHAASO合作报告了从5个微类星体中探测到 >； 100 TeV γ射线发射，这表明这些源是有效的粒子加速器。在微类星体中，高能γ射线可以在大规模喷流或风中产生。在这项工作中，我们研究了SS 433， V4641 Sgr和GRS 1905+105的x射线，γ射线和中微子发射。我们考虑了轻子和强子场景来解释LHAASO和其他高能γ射线探测器观测到的光谱。我们估计了与强子分量相关的中微子通量，并在当前和未来的中微子望远镜中研究了这些源的中微子的可探测性。我们发现，在三个源中，Sgr V4641具有最好的观测前景。
{"title":"Multimessenger emission from very-high-energy black hole-jet systems in the milky way","authors":"Jose A. Carpio, Ali Kheirandish, Bing Zhang","doi":"10.1016/j.jheap.2025.100538","DOIUrl":"10.1016/j.jheap.2025.100538","url":null,"abstract":"<div><div>Microquasars, compact binary systems with an accreting stellar-mass black hole or neutron star, are promising candidates for high-energy particle acceleration. Recently, the LHAASO collaboration reported on the detection of > 100 TeV <em>γ</em>-ray emission from five microquasars, suggesting that these sources are efficient particle accelerators. In microquasars, high-energy <em>γ</em>-rays can be produced in large-scale jets or winds. In this work, we explore the X-ray, <em>γ</em>-ray and neutrino emission from SS 433, V4641 Sgr and GRS 1905+105. We consider leptonic and hadronic scenarios to explain the spectra observed by LHAASO and other high-energy <em>γ</em>-ray detectors. We estimate the neutrino flux associated with the hadronic component and investigate the detectability of neutrinos from these sources in current and future neutrino telescopes. We find that among the three sources, V4641 Sgr has the best prospects of observation with a combined next-generation neutrino telescopes.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"51 ","pages":"Article 100538"},"PeriodicalIF":10.5,"publicationDate":"2025-12-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145884295","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}
The AT2017gfo kilonova transient remains a unique multi-messenger event thanks to its proximity () and the possibility to investigate time-resolved spectra, thus providing evidence of r-process nucleosynthesis. The kilonova signal was extensively studied in the spectral and time domains, providing key insights into the chemical composition and physical properties of the ejecta. Here, we report the discovery of a novel correlation between two fundamental observables: the peak energy of the EFE spectrum, Ep, and the isotropic-equivalent luminosity, Liso. In particular, we show that up to about 2.5 days after the merger, the AT2017gfo spectrum evolves according to: while in the subsequent epochs, Ep remains almost constant with Liso, flattening around 1 eV. Exploiting simulations from a state-of-the-art radiative transfer code, we demonstrate that our kilonova model inherently predicts this peculiar correlation, hence suggesting a new diagnostic tool for comparing observables against simulations. Future kilonova observations will provide additional insight into the physics behind the correlation.
{"title":"The Ep−Liso correlation: A new diagnostic tool for kilonova transients","authors":"Ruben Farinelli , Fabrizio Cogato , Mattia Bulla , Paramvir Singh , Giulia Stratta , Andrea Rossi , Eliana Palazzi , Cristiano Guidorzi , Elisabetta Maiorano , Lorenzo Amati , Bing Zhang , Luciano Rezzolla , Filippo Frontera","doi":"10.1016/j.jheap.2025.100532","DOIUrl":"10.1016/j.jheap.2025.100532","url":null,"abstract":"<div><div>The AT2017gfo kilonova transient remains a unique multi-messenger event thanks to its proximity (<span><math><mrow><mi>z</mi><mo>=</mo><mn>0.00987</mn></mrow></math></span>) and the possibility to investigate time-resolved spectra, thus providing evidence of r-process nucleosynthesis. The kilonova signal was extensively studied in the spectral and time domains, providing key insights into the chemical composition and physical properties of the ejecta. Here, we report the discovery of a novel correlation between two fundamental observables: the peak energy of the <em>E</em> <em>F<sub>E</sub></em> spectrum, <em>E</em><sub>p</sub>, and the isotropic-equivalent luminosity, <em>L</em><sub>iso</sub>. In particular, we show that up to about 2.5 days after the merger, the AT2017gfo spectrum evolves according to: <span><math><mrow><msub><mtext>log</mtext><mn>10</mn></msub><mrow><mo>[</mo><msub><mi>E</mi><mrow><mi>p</mi></mrow></msub><mo>/</mo><mtext>eV</mtext><mo>]</mo></mrow><mo>=</mo><mo>−</mo><mn>0</mn><mo>.</mo><msubsup><mn>13</mn><mrow><mo>−</mo><mn>0.02</mn></mrow><mrow><mo>+</mo><mn>0.02</mn></mrow></msubsup><mo>+</mo><mn>0</mn><mo>.</mo><msubsup><mn>62</mn><mrow><mo>−</mo><mn>0.02</mn></mrow><mrow><mo>+</mo><mn>0.02</mn></mrow></msubsup><mspace></mspace><msub><mtext>log</mtext><mn>10</mn></msub><mrow><mo>[</mo><msub><mi>L</mi><mrow><mrow><mi>i</mi></mrow><mi>s</mi><mi>o</mi></mrow></msub><mo>/</mo><mrow><mo>(</mo><msup><mn>10</mn><mn>41</mn></msup><mspace></mspace><mtext>erg</mtext><mspace></mspace><msup><mtext>s</mtext><mrow><mo>−</mo><mn>1</mn></mrow></msup><mo>)</mo></mrow><mo>]</mo></mrow><mspace></mspace><mrow><mo>(</mo><mn>68</mn><mspace></mspace><mo>%</mo><mspace></mspace><mrow><mrow><mi>C</mi></mrow><mo>.</mo><mi>L</mi><mo>.</mo></mrow><mo>)</mo></mrow></mrow></math></span> while in the subsequent epochs, <em>E</em><sub>p</sub> remains almost constant with <em>L</em><sub>iso</sub>, flattening around 1 eV. Exploiting simulations from a state-of-the-art radiative transfer code, we demonstrate that our kilonova model inherently predicts this peculiar correlation, hence suggesting a new diagnostic tool for comparing observables against simulations. Future kilonova observations will provide additional insight into the physics behind the <span><math><mrow><msub><mi>E</mi><mrow><mi>p</mi></mrow></msub><mo>−</mo><msub><mi>L</mi><mrow><mrow><mi>i</mi></mrow><mi>s</mi><mi>o</mi></mrow></msub></mrow></math></span> correlation.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"51 ","pages":"Article 100532"},"PeriodicalIF":10.5,"publicationDate":"2025-12-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145884294","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}
Pub Date : 2025-12-20DOI: 10.1016/j.jheap.2025.100535
Aromal P , Unnati Kashyap , Manoneeta Chakraborty , Sudip Bhattacharyya , Thomas J. Maccarone , Vijay Choudhary
We present a detailed analysis of the Type-I (thermonuclear) X-ray bursts and eclipses observed from the neutron star low-mass X-ray binary EXO 0748–676 with AstroSat during the second known outburst of the source following a 16-year-long quiescence period. We detect three thermonuclear X-ray bursts, with two displaying simultaneous coverage in the soft X-rays. Simultaneous UV observations show evidence of reprocessed burst emissions in the far-ultraviolet band. The time-resolved spectral analysis reveals the photospheric radius expansion (PRE) nature for two bursts. We estimate the distance to the source to be 7.42 ± 0.53 kpc using the peak flux of PRE. Notably, one of the bursts exhibited a secondary peak, ∼ 30 s after the primary, particularly dominating in the softer X-rays, which reveals a correlation with the evolution of burst hotspot radius with no temperature dependence. The burst properties and corresponding flux values suggest that mixed H/He burning may have fueled the bursts. We also detect evidence of a soft excess during one burst, likely arising from the interaction of the burst photons with the surroundings. We also probe the temporal evolution and the energy dependence of the eclipses, which offer insights into the binary environment. Our study helps gain deeper insight into the physics of burst ignition, flame propagation, the burst-accretion interaction, and the evolution of LMXBs.
{"title":"The 2024 outburst of the neutron star LMXB EXO 0748–676: An investigation of bursts and eclipses with astrosat","authors":"Aromal P , Unnati Kashyap , Manoneeta Chakraborty , Sudip Bhattacharyya , Thomas J. Maccarone , Vijay Choudhary","doi":"10.1016/j.jheap.2025.100535","DOIUrl":"10.1016/j.jheap.2025.100535","url":null,"abstract":"<div><div>We present a detailed analysis of the Type-I (thermonuclear) X-ray bursts and eclipses observed from the neutron star low-mass X-ray binary EXO 0748–676 with AstroSat during the second known outburst of the source following a 16-year-long quiescence period. We detect three thermonuclear X-ray bursts, with two displaying simultaneous coverage in the soft X-rays. Simultaneous UV observations show evidence of reprocessed burst emissions in the far-ultraviolet band. The time-resolved spectral analysis reveals the photospheric radius expansion (PRE) nature for two bursts. We estimate the distance to the source to be 7.42 ± 0.53 kpc using the peak flux of PRE. Notably, one of the bursts exhibited a secondary peak, ∼ 30 s after the primary, particularly dominating in the softer X-rays, which reveals a correlation with the evolution of burst hotspot radius with no temperature dependence. The burst properties and corresponding flux values suggest that mixed H/He burning may have fueled the bursts. We also detect evidence of a soft excess during one burst, likely arising from the interaction of the burst photons with the surroundings. We also probe the temporal evolution and the energy dependence of the eclipses, which offer insights into the binary environment. Our study helps gain deeper insight into the physics of burst ignition, flame propagation, the burst-accretion interaction, and the evolution of LMXBs.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"51 ","pages":"Article 100535"},"PeriodicalIF":10.5,"publicationDate":"2025-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145884293","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}
Pub Date : 2025-12-17DOI: 10.1016/j.jheap.2025.100533
Andronikos Paliathanasis , Genly Leon , Yoelsy Leyva , Giuseppe Gaetano Luciano , Amare Abebe
We study quantum corrections to the ΛCDM model arising from a minimum measurable length in Heisenberg’s uncertainty principle. We focus on a higher-order Generalized Uncertainty Principle, beyond the quadratic form. This generalized GUP introduces two free parameters, and we determine the modified Friedmann equation. This framework leads to a perturbative cosmological model that naturally reduces to ΛCDM in an appropriate limiting case of the deformation parameters. We construct the modified cosmological scenario, analyze its deviations from the standard case, and examine it as a mechanism for the description of dynamical dark energy. To constrain the model, we employ Cosmic Chronometers, the latest Baryon Acoustic Oscillations from the DESI DR2 release, and Supernova data from the PantheonPlus and Union3 catalogues. Our analysis indicates that the modified GUP model is statistically competitive with the ΛCDM scenario, providing comparable or even improved fits to some of the combined datasets. Moreover, the data constrain the deformation parameter of the GUP model, with the preferred value found to be negative, which corresponds to a phantom regime in the effective dynamical dark energy description.
{"title":"Challenging ΛCDM with higher-order GUP corrections","authors":"Andronikos Paliathanasis , Genly Leon , Yoelsy Leyva , Giuseppe Gaetano Luciano , Amare Abebe","doi":"10.1016/j.jheap.2025.100533","DOIUrl":"10.1016/j.jheap.2025.100533","url":null,"abstract":"<div><div>We study quantum corrections to the ΛCDM model arising from a minimum measurable length in Heisenberg’s uncertainty principle. We focus on a higher-order Generalized Uncertainty Principle, beyond the quadratic form. This generalized GUP introduces two free parameters, and we determine the modified Friedmann equation. This framework leads to a perturbative cosmological model that naturally reduces to ΛCDM in an appropriate limiting case of the deformation parameters. We construct the modified cosmological scenario, analyze its deviations from the standard case, and examine it as a mechanism for the description of dynamical dark energy. To constrain the model, we employ Cosmic Chronometers, the latest Baryon Acoustic Oscillations from the DESI DR2 release, and Supernova data from the PantheonPlus and Union3 catalogues. Our analysis indicates that the modified GUP model is statistically competitive with the ΛCDM scenario, providing comparable or even improved fits to some of the combined datasets. Moreover, the data constrain the deformation parameter of the GUP model, with the preferred value found to be negative, which corresponds to a phantom regime in the effective dynamical dark energy description.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"51 ","pages":"Article 100533"},"PeriodicalIF":10.5,"publicationDate":"2025-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145839881","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}
Pub Date : 2025-12-16DOI: 10.1016/j.jheap.2025.100534
Ziyan Zhu , Qingquan Jiang , Yu Liu , Puxun Wu , Nan Liang
In this work, we constrain the phenomenological interacting dark energy (IDE) model using Fermi gamma-ray burst (GRB) dataset and the latest baryon acoustic oscillation (BAO) data from the Dark Energy Spectroscopic Instrument (DESI) Data Release 2 (DR2). Through a joint Bayesian analysis, we perform a cosmological comparative assessment of the ΛCDM, wCDM, and CPL models with the phenomenological IDE model. For the phenomenological IDE model in a flat universe with Fermi samples and DESI DR2, we obtain: , with the GOLD sample (1.4 ≤ z ≤ 5.6) and , with the FULL sample (1.4 ≤ z ≤ 8.2), respectively. Our analysis shows that the ΛCDM model without interaction (, ) is consistent with the latest Fermi sample and DESI DR2 at 1σ confidence level. We find no significant deviations from the standard model using AIC and BIC criterias.
在这项工作中，我们使用费米伽玛射线暴（GRB）数据集和暗能量光谱仪器（DESI）数据发布2 （DR2）最新的重子声学振荡（BAO）数据来约束现象相互作用暗能量（IDE）模型。通过联合贝叶斯分析，我们对ΛCDM、wCDM和CPL模型与现象学IDE模型进行了宇宙学比较评估。对于Fermi样本和DESI DR2在平坦宇宙中的现象学IDE模型，我们得到：对于GOLD样本（1.4 ≤ z ≤ 5.6），ξ=2.63−0.52+0.63,ξ+3wX=−0.98−2.07+1.90；对于FULL样本（1.4 ≤ z ≤ 8.2），ξ=2.83−0.58+0.63,ξ+3wX=0.03−1.33+1.35。我们的分析表明，无相互作用（ξ=3, ξ+3wX=0）的ΛCDM模型与最新费米样本和DESI DR2在1σ置信水平上是一致的。我们发现使用AIC和BIC标准模型没有明显的偏差。
{"title":"Cosmological constraints on the phenomenological interacting dark energy model with Fermi gamma-ray bursts and DESI DR2","authors":"Ziyan Zhu , Qingquan Jiang , Yu Liu , Puxun Wu , Nan Liang","doi":"10.1016/j.jheap.2025.100534","DOIUrl":"10.1016/j.jheap.2025.100534","url":null,"abstract":"<div><div>In this work, we constrain the phenomenological interacting dark energy (IDE) model using <em>Fermi</em> gamma-ray burst (GRB) dataset and the latest baryon acoustic oscillation (BAO) data from the Dark Energy Spectroscopic Instrument (DESI) Data Release 2 (DR2). Through a joint Bayesian analysis, we perform a cosmological comparative assessment of the ΛCDM, <em>w</em>CDM, and CPL models with the phenomenological IDE model. For the phenomenological IDE model in a flat universe with <em>Fermi</em> samples and DESI DR2, we obtain: <span><math><mrow><mi>ξ</mi><mo>=</mo><mn>2</mn><mo>.</mo><msubsup><mn>63</mn><mrow><mo>−</mo><mn>0.52</mn></mrow><mrow><mo>+</mo><mn>0.63</mn></mrow></msubsup></mrow></math></span>, <span><math><mrow><mi>ξ</mi><mo>+</mo><mn>3</mn><msub><mi>w</mi><mi>X</mi></msub><mo>=</mo><mo>−</mo><mn>0</mn><mo>.</mo><msubsup><mn>98</mn><mrow><mo>−</mo><mn>2.07</mn></mrow><mrow><mo>+</mo><mn>1.90</mn></mrow></msubsup></mrow></math></span> with the GOLD sample (1.4 ≤ <em>z</em> ≤ 5.6) and <span><math><mrow><mi>ξ</mi><mo>=</mo><mn>2</mn><mo>.</mo><msubsup><mn>83</mn><mrow><mo>−</mo><mn>0.58</mn></mrow><mrow><mo>+</mo><mn>0.63</mn></mrow></msubsup></mrow></math></span>, <span><math><mrow><mi>ξ</mi><mo>+</mo><mn>3</mn><msub><mi>w</mi><mi>X</mi></msub><mo>=</mo><mn>0</mn><mo>.</mo><msubsup><mn>03</mn><mrow><mo>−</mo><mn>1.33</mn></mrow><mrow><mo>+</mo><mn>1.35</mn></mrow></msubsup></mrow></math></span> with the FULL sample (1.4 ≤ <em>z</em> ≤ 8.2), respectively. Our analysis shows that the ΛCDM model without interaction (<span><math><mrow><mi>ξ</mi><mo>=</mo><mn>3</mn></mrow></math></span>, <span><math><mrow><mi>ξ</mi><mo>+</mo><mn>3</mn><msub><mi>w</mi><mi>X</mi></msub><mo>=</mo><mn>0</mn></mrow></math></span>) is consistent with the latest <em>Fermi</em> sample and DESI DR2 at 1<em>σ</em> confidence level. We find no significant deviations from the standard model using AIC and BIC criterias.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"51 ","pages":"Article 100534"},"PeriodicalIF":10.5,"publicationDate":"2025-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145797357","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}
Pub Date : 2025-12-11DOI: 10.1016/j.jheap.2025.100531
Zohdieh Ossoulian, Tayeb Golanbari, Khaled Saaidi
The latest CMB data from ACT DR6, in combination with Planck, DESI, and BICEP/Keck, indicate a slight upward shift in the scalar spectral index. This trend puts several previously favored inflationary models under tension. In this work, we study an inflationary scenario in the framework of f(R, T) gravity, where R is the Ricci scalar and T is the trace of the energy-momentum tensor, with a nonminimal coupling between matter and curvature. The inflaton is assumed to be a noncanonical scalar field with a generalized kinetic energy. To analyze the dynamics of inflation, we employ the Hamilton-Jacobi formalism, where the Hubble parameter is expressed as a function of the scalar field rather than the potential. Within this setup, we examine two functional forms of the Hubble parameter, a power-law and an exponential form, and derive key observables such as the scalar spectral index ns and the tensor-to-scalar ratio r. Comparing the results with ACT DR6, we explore the parameter space of the model. We find that the power-law case fits the data well across a wide range of free parameters, while the exponential case requires a large number of e-folds to be consistent with observations. After inflation, we study reheating, where the dynamics of reheating and inflation are closely linked. Taking into account the overproduction of primordial gravitational waves constrained by the observational bound on ΔNeff, we obtain a lower limit on the reheating temperature, which is especially restrictive for the stiff equation of state ωre. This bound implies that the number of e-folds of inflation should generally not exceed N ≲ 64(65). The resulting energy spectrum of gravitational waves exhibits an enhanced amplitude, thereby bringing it within the observable range of upcoming detectors. We also check the consistency of the model with the Swampland conjectures and the Trans-Planckian Censorship Conjecture (TCC). Our results demonstrate that combining f(R, T) gravity with noncanonical field dynamics provides a rich and testable framework for the early universe. In addition, the Hamilton-Jacobi approach, by avoiding extra approximations, yields a clearer picture of inflation in modified gravity and opens new directions for addressing fundamental problems in high-energy cosmology.
{"title":"Hamilton-Jacobi analysis of noncanonical inflation in f(R, T) gravity: Constraints from planck/ACT data, and theoretical bounds","authors":"Zohdieh Ossoulian, Tayeb Golanbari, Khaled Saaidi","doi":"10.1016/j.jheap.2025.100531","DOIUrl":"10.1016/j.jheap.2025.100531","url":null,"abstract":"<div><div>The latest CMB data from ACT DR6, in combination with Planck, DESI, and BICEP/Keck, indicate a slight upward shift in the scalar spectral index. This trend puts several previously favored inflationary models under tension. In this work, we study an inflationary scenario in the framework of <em>f</em>(<em>R, T</em>) gravity, where <em>R</em> is the Ricci scalar and <em>T</em> is the trace of the energy-momentum tensor, with a nonminimal coupling between matter and curvature. The inflaton is assumed to be a noncanonical scalar field with a generalized kinetic energy. To analyze the dynamics of inflation, we employ the Hamilton-Jacobi formalism, where the Hubble parameter is expressed as a function of the scalar field rather than the potential. Within this setup, we examine two functional forms of the Hubble parameter, a power-law and an exponential form, and derive key observables such as the scalar spectral index <em>n<sub>s</sub></em> and the tensor-to-scalar ratio <em>r</em>. Comparing the results with ACT DR6, we explore the parameter space of the model. We find that the power-law case fits the data well across a wide range of free parameters, while the exponential case requires a large number of e-folds to be consistent with observations. After inflation, we study reheating, where the dynamics of reheating and inflation are closely linked. Taking into account the overproduction of primordial gravitational waves constrained by the observational bound on Δ<em>N</em><sub>eff</sub>, we obtain a lower limit on the reheating temperature, which is especially restrictive for the stiff equation of state <em>ω</em><sub>re</sub>. This bound implies that the number of e-folds of inflation should generally not exceed <em>N</em> ≲ 64(65). The resulting energy spectrum of gravitational waves exhibits an enhanced amplitude, thereby bringing it within the observable range of upcoming detectors. We also check the consistency of the model with the Swampland conjectures and the Trans-Planckian Censorship Conjecture (TCC). Our results demonstrate that combining <em>f</em>(<em>R, T</em>) gravity with noncanonical field dynamics provides a rich and testable framework for the early universe. In addition, the Hamilton-Jacobi approach, by avoiding extra approximations, yields a clearer picture of inflation in modified gravity and opens new directions for addressing fundamental problems in high-energy cosmology.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"51 ","pages":"Article 100531"},"PeriodicalIF":10.5,"publicationDate":"2025-12-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145797474","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}
Pub Date : 2025-12-04DOI: 10.1016/j.jheap.2025.100530
D. Pugliese , Z. Stuchlík
A Ringed Accretion disk (RAD) is a cluster of axially symmetric, mixed co–rotating and counter–rotating co–planar tori, orbiting on the equatorial plane of a central Kerr black hole (BH). In this work we focus on the red-shift and spectral lines emission from the RAD. Our analysis of the emissions maps, giving appearance of the RAD, envisages the possibility that the presence of a possible disk internal ringed structure could be observable from a density radial discrete structure, and a composite radial distribution of angular momentum in the disk. The co–rotating and counter–rotating bands, in the disk internal structure, are found distinguished in red-shift, in dependence on the view angle, and the BH spin. We frame our investigation, using different source corona models, and emissivity profiles for the disk. Lines emission turns affected by the knobby surface of the disk. The results of this analysis have been compared with the results for the infinite disk and the correspondent unstructured disks.
{"title":"The red-shift and spectral lines of the Kerr black hole ringed accretion disks","authors":"D. Pugliese , Z. Stuchlík","doi":"10.1016/j.jheap.2025.100530","DOIUrl":"10.1016/j.jheap.2025.100530","url":null,"abstract":"<div><div>A Ringed Accretion disk (<strong>RAD</strong>) is a cluster of axially symmetric, mixed co–rotating and counter–rotating co–planar tori, orbiting on the equatorial plane of a central Kerr black hole (<strong>BH</strong>). In this work we focus on the red-shift and spectral lines emission from the <strong>RAD</strong>. Our analysis of the emissions maps, giving appearance of the <strong>RAD</strong>, envisages the possibility that the presence of a possible disk internal ringed structure could be observable from a density radial discrete structure, and a composite radial distribution of angular momentum in the disk. The co–rotating and counter–rotating bands, in the disk internal structure, are found distinguished in red-shift, in dependence on the view angle, and the <strong>BH</strong> spin. We frame our investigation, using different source corona models, and emissivity profiles for the disk. Lines emission turns affected by the knobby surface of the disk. The results of this analysis have been compared with the results for the infinite disk and the correspondent unstructured disks.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"51 ","pages":"Article 100530"},"PeriodicalIF":10.5,"publicationDate":"2025-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145748542","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}
Pub Date : 2025-12-04DOI: 10.1016/j.jheap.2025.100529
Na Wang , Guowei Ren , Shun Zhang , Tingfeng Yi , Tong Liu , Mouyuan Sun
Based on the Zwicky Transient Facility (ZTF), we selected 10 blazars as our sample sources. Among these, we found four blazars (J 0923.5+4125, J 1221.3+3010, J 1503.5+4759, and J 1652.7+4024) showing possible indications of quasi periodic oscillations (QPOs) modulation. We conducted a detailed analysis of their optical light curves (g- and r-bands) over the past five years using the root mean square (RMS)-Flux relation, flux distribution, and QPO detection methods to investigate their variability characteristics. A linear RMS-Flux relation is present in both bands, and their flux distributions follow a log-normal form. This suggests that optical variability may arise from multiplicative, nonlinear processes across different timescales and flux states. Further QPO analysis using the weighted wavelet Z-transform (WWZ), Lomb-Scargle periodogram (LSP), and autoregressive integrated moving average (ARIMA) methods identified candidate periodic signals in four blazars. J 0923.5+4125 (period ∼ 205 days) and J 1221.3+3010 ( ∼ 630 days) show local significances of ∼ 3σ, whereas J 1503.5+4759 ( ∼ 38.5 days) and J 1652.7+4024 ( ∼ 48 days) reach ∼ 4σ. After accounting for the look-elsewhere effect, the global significances for J 1503.5+4759 in the g- and r-bands are ∼ 2.7σ, while for J 1652.7+4024 they are approximately ∼ 2.5σ in both bands. These two blazars warrant further monitoring and investigation.
{"title":"Possible quasi-periodic optical oscillations of ZTF blazars","authors":"Na Wang , Guowei Ren , Shun Zhang , Tingfeng Yi , Tong Liu , Mouyuan Sun","doi":"10.1016/j.jheap.2025.100529","DOIUrl":"10.1016/j.jheap.2025.100529","url":null,"abstract":"<div><div>Based on the Zwicky Transient Facility (ZTF), we selected 10 blazars as our sample sources. Among these, we found four blazars (J 0923.5+4125, J 1221.3+3010, J 1503.5+4759, and J 1652.7+4024) showing possible indications of quasi periodic oscillations (QPOs) modulation. We conducted a detailed analysis of their optical light curves (g- and r-bands) over the past five years using the root mean square (RMS)-Flux relation, flux distribution, and QPO detection methods to investigate their variability characteristics. A linear RMS-Flux relation is present in both bands, and their flux distributions follow a log-normal form. This suggests that optical variability may arise from multiplicative, nonlinear processes across different timescales and flux states. Further QPO analysis using the weighted wavelet Z-transform (WWZ), Lomb-Scargle periodogram (LSP), and autoregressive integrated moving average (ARIMA) methods identified candidate periodic signals in four blazars. J 0923.5+4125 (period ∼ 205 days) and J 1221.3+3010 ( ∼ 630 days) show local significances of ∼ 3<em>σ</em>, whereas J 1503.5+4759 ( ∼ 38.5 days) and J 1652.7+4024 ( ∼ 48 days) reach ∼ 4<em>σ</em>. After accounting for the look-elsewhere effect, the global significances for J 1503.5+4759 in the g- and r-bands are ∼ 2.7<em>σ</em>, while for J 1652.7+4024 they are approximately ∼ 2.5<em>σ</em> in both bands. These two blazars warrant further monitoring and investigation.</div></div>","PeriodicalId":54265,"journal":{"name":"Journal of High Energy Astrophysics","volume":"51 ","pages":"Article 100529"},"PeriodicalIF":10.5,"publicationDate":"2025-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145748543","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}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号