Journal of Cosmology and Astroparticle Physics最新文献_第6页

Kinetic field theory of compact systems 紧致系统的动力学场论

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2026-07-21 DOI: 10.1088/1475-7516/2026/07/071

Matthias Bartelmann and James Stokes

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The open-universe signal in late-time observations: a model artifact rather than genuine curvature 后期观测中的开放宇宙信号：一个模型伪影，而不是真正的曲率

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2026-07-21 DOI: 10.1088/1475-7516/2026/07/075

Peng-Ju Wu

引用次数: 0

Nonlinear relativistic effects on cosmological redshift drift 非线性相对论对宇宙红移漂移的影响

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2026-07-20 DOI: 10.1088/1475-7516/2026/07/070

P. Béchaz, G. Fanizza, G. Marozzi and M.R. Medeiros Silva

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Slow-down of expanding bubbles in the early Universe 早期宇宙中膨胀气泡的减速

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2026-07-19 DOI: 10.1088/1475-7516/2026/07/068

Nabeen Bhusal, Simone Blasi, Thomas Konstandin, Enrico Perboni and Jorinde van de Vis

{"title":"Slow-down of expanding bubbles in the early Universe","authors":"Nabeen Bhusal, Simone Blasi, Thomas Konstandin, Enrico Perboni and Jorinde van de Vis","doi":"10.1088/1475-7516/2026/07/068","DOIUrl":"https://doi.org/10.1088/1475-7516/2026/07/068","url":null,"abstract":"We study slow-down effects for bubbles formed in a cosmological first-order phase transition (PT) focusing on deflagrations and hybrids, where the bubble wall is preceded by a shockwave of heated plasma. Slow-down has been observed in multi-bubble simulations together with a suppression of gravitational wave (GW) emission, mostly for slow walls. We study the impact of the shock waves on the wall velocity around percolation, by considering steady-state single-bubble solutions and incorporating the possible heating effects by two different mechanisms. First, we investigate the slow-down experienced by a bubble expanding into an impeding shockwave, where the temperature is higher than at nucleation, and the fluid is no longer at rest. Taking into account such heating and kinematic effects, we find that the most significant slow-down occurs for the fastest walls, and thus cannot explain the suppression of the GWs observed in the simulations. However, these effects are stronger for PTs with a sizeable change in degrees of freedom unlike what is usually implemented in simulations, suggesting that the degrees of freedom can be an important additional parameter for characterizing the GW spectrum. For the second slow-down mechanism, we study heated droplets of false vacuum that shrink towards the end of the PT. By implementing a suitable boundary condition motivated by energy conservation, we show how the droplet velocity, interpreted here as the late-time velocity of the bubble walls, can be predicted from the properties of the initial deflagration/hybrid, in remarkable agreement with numerical simulations. Droplets are found to shrink more slowly for stronger PTs and slower deflagrations, with a mild dependence on the change of degrees of freedom. Such slow droplets naturally correlate with a suppression of GWs, while geometrical properties such as the shock width play an important role as well.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"11 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2026-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148522546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

引用次数: 0

Sensitivity to axion-like particle dark matter with very-high-energy gamma-ray observations of active galactic nuclei located behind galaxy clusters 对位于星系团后面的活动星系核的高能伽玛射线观测的轴子样粒子暗物质的灵敏度

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2026-07-19 DOI: 10.1088/1475-7516/2026/07/066

Cervane Grimaud, Denys Malyshev and Emmanuel Moulin

{"title":"Sensitivity to axion-like particle dark matter with very-high-energy gamma-ray observations of active galactic nuclei located behind galaxy clusters","authors":"Cervane Grimaud, Denys Malyshev and Emmanuel Moulin","doi":"10.1088/1475-7516/2026/07/066","DOIUrl":"https://doi.org/10.1088/1475-7516/2026/07/066","url":null,"abstract":"Axion-Like-Particles (ALPs) are hypothetical pseudo-scalar particles actively searched as light dark matter candidates. The coupling of ALPs to photons can give rise to distinctive spectral features in the observed gamma-ray spectrum of astrophysical sources. We perform a forecast study on the sensitivity to ALP-photon interactions using stacked mock observations of selected active galactic nuclei (AGNs) located behind galaxy clusters (GC). The ALP-photon conversion in the magnetic fields of galaxy clusters give rise to absorption-like features in AGN spectra that are subject to large variance in their prediction for individual sources. We consider here a stacking analysis of multiple AGN-cluster pairs, which yields a more controlled prediction of the expected ALP-induced spectral patterns in the observed gamma-ray spectra. Using realistic mock observations of selected Fermi-LAT AGNs by ongoing Imaging Atmospheric Cherenkov Telescopes such as H.E.S.S., MAGIC and VERITAS, we provide a careful assessment of the expected sensitivity of a combined statistical analysis of many AGN-GC pairs, together with the impact of modelling and instrumental uncertainties. The sensitivity reaches ALP-photon couplings down to 6 × 10-13 GeV-1 for an ALP mass of 3 × 10-8 eV, and is currently statistically dominated indicating further improvements from more observations. Such a stacking analysis approach enables exploration of the yet-uncharted ALP dark matter parameter space in the 10-8–10-7 eV mass range.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"4 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2026-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148522544","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

引用次数: 0

Dynamics, ringdown, and accretion-driven multiple quasi-periodic oscillations of Kerr–Bertotti–Robinson black holes kerr - bertoti - robinson黑洞的动力学、衰荡和吸积驱动的多重准周期振荡

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2026-07-19 DOI: 10.1088/1475-7516/2026/07/065

G. Mustafa, Orhan Donmez, Dhruba Jyoti Gogoi, Sushant G. Ghosh, Ibrar Hussain and Chengxun Yuan

{"title":"Dynamics, ringdown, and accretion-driven multiple quasi-periodic oscillations of Kerr–Bertotti–Robinson black holes","authors":"G. Mustafa, Orhan Donmez, Dhruba Jyoti Gogoi, Sushant G. Ghosh, Ibrar Hussain and Chengxun Yuan","doi":"10.1088/1475-7516/2026/07/065","DOIUrl":"https://doi.org/10.1088/1475-7516/2026/07/065","url":null,"abstract":"We study the motion of test particles around the Kerr–Bertotti–Robinson (KBR) black hole (BH) and explore how the three defining parameters, the mass M, rotation parameter a, and magnetic parameter B influence their dynamics. We derive analytical expressions for the energy and angular momentum of stable equatorial circular orbits, along with the corresponding radial and latitudinal oscillation frequencies, as functions of M, a, and B. We also examine the key features of the quasi-periodic oscillations (QPOs) of test particles near stable circular orbits, including the precession effects such as periastron precession and the Lense-Thirring effect. We compare our results with those corresponding to the Kerr BH. We find that the particle motion is strongly shaped by the BH parameters. Using a WKB approach, we also study scalar quasinormal modes of rotating KBR BH in an external magnetic field and show that the magnetic field increases damping, while rotation and angular momentum mainly set the oscillation frequencies. Alternatively, general relativistic modeling of Bondi-Hoyle-Lyttleton (BHL) accretion onto rapidly rotating KBR BH shows that two distinct physical structures emerge and cyclically transform into one another over time. These processes produce either a strongly oscillating flip–flop shock cone or a nearly stationary toroidal structure, with their formation governed by the BH spin and magnetic curvature. Power spectral analysis shows that these configurations give rise to low- and high-frequency QPO, providing a unified theoretical framework to understand how multiple QPO–like features can arise in rapidly spinning accreting systems.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"37 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2026-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148522542","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

引用次数: 0

Cosmic voids evolution in modified gravity via hydrodynamics 通过流体力学修正重力下的宇宙空洞演化

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2026-07-19 DOI: 10.1088/1475-7516/2026/07/069

Tommaso Moretti, Noemi Frusciante, Giovanni Verza and Francesco Pace

{"title":"Cosmic voids evolution in modified gravity via hydrodynamics","authors":"Tommaso Moretti, Noemi Frusciante, Giovanni Verza and Francesco Pace","doi":"10.1088/1475-7516/2026/07/069","DOIUrl":"https://doi.org/10.1088/1475-7516/2026/07/069","url":null,"abstract":"We present a hydrodynamical description of isolated spherical voids in modified gravity (MG), extending the standard General Relativity (GR) and dynamical dark energy treatment by encoding gravity modifications into effective couplings that enter the Euler and Poisson equations. This yields a compact non-linear evolution equation for the Eulerian density contrast, controlled by a time- and density-dependent effective gravitational strength, and provides a direct map between model functions and void observables. We apply the framework to the luminal Galileon class of models, where derivative self-interactions generate Vainshtein screening and might lead to a breakdown of the physical branch in sufficiently underdense regions. Exploiting this feature, we apply the void-informed viability requirement that translates into bounds on the theory parameter space and, equivalently, on the minimum attainable void depth as a function of redshift. For viable parameters of a concrete model, we quantify the impact of MG on isolated void evolution, the Lagrangian to Eulerian mapping, and the shell-crossing threshold. Relative to GR, we find a clear hierarchy of MG effects, with 𝒪(10%) modifications in the gravitational couplings, percent-level shifts in the void density evolution, and sub-percent deviations in both the mapping and the shell-crossing thresholds. Moreover, within the adopted parametrization, we show analytically that voids always lie in an unscreened regime on the physical branch. Overall, the formalism provides a self-consistent route to predict void dynamics and consistency constraints in a broad class of MG models.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"68 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2026-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148522484","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

引用次数: 0

The glow of Axion Quark Nugget dark matter. Part IV. CMB spectral and anisotropy signatures 轴子夸克块暗物质的辉光。第四部分：CMB光谱和各向异性特征

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2026-07-19 DOI: 10.1088/1475-7516/2026/07/067

Fereshteh Majidi, Xunyu Liang, Michael Sekatchev, Ludovic Van Waerbeke and Ariel Zhitnitsky

{"title":"The glow of Axion Quark Nugget dark matter. Part IV. CMB spectral and anisotropy signatures","authors":"Fereshteh Majidi, Xunyu Liang, Michael Sekatchev, Ludovic Van Waerbeke and Ariel Zhitnitsky","doi":"10.1088/1475-7516/2026/07/067","DOIUrl":"https://doi.org/10.1088/1475-7516/2026/07/067","url":null,"abstract":"Axion quark nuggets (AQNs) are macroscopic dark-matter candidates, with masses of the order of a few grams to a kilogram and sub-micron radius, thought to form at the Quantum Chromo Dynamic era through axion-induced charge separation. This framework naturally links the dark and visible matter abundances (ΩDM ∼ Ωvisible) and provides a mechanism for generating the baryon-antibaryon asymmetry where dark matter is composed of matter AQNs and antimatter AQNs. Although behaving as cold dark matter on cosmological scales, baryons annihilate with antimatter AQNs, producing ionizing high-energy photons. The resulting energy injection may imprint spectral distortions on the cosmic microwave background (CMB) and modify the reionization history. Using a modified version of the CLASS Boltzmann code we compute the impact of this energy injection on the μ and y spectral distortion parameters as well as on the optical depth. We find that (1) the CMB anisotropies remain essentially unaffected by baryon annihilation, and (2) the associated spectral distortion signatures lie within the sensitivity reach of proposed CMB spectral distortion missions. Finally, we discuss the similarities and differences between the AQN scenario and annihilating or decaying dark matter models.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"50 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2026-07-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148522545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

引用次数: 0

Minimal Dark Matter in the sky: updated Indirect Detection probes 天空中最小的暗物质：更新的间接探测探测器

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2026-07-16 DOI: 10.1088/1475-7516/2026/07/063

Mohammad Aghaie, Alessandro Dondarini, Giulio Marino and Paolo Panci

{"title":"Minimal Dark Matter in the sky: updated Indirect Detection probes","authors":"Mohammad Aghaie, Alessandro Dondarini, Giulio Marino and Paolo Panci","doi":"10.1088/1475-7516/2026/07/063","DOIUrl":"https://doi.org/10.1088/1475-7516/2026/07/063","url":null,"abstract":"Minimal Dark Matter is among the simplest and most predictive Dark Matter frameworks, with the Majorana SU(2) 5-plet as its smallest accidentally stable real representation. We present a comprehensive reassessment of its indirect-detection signals. The γ-ray flux from both Sommerfeld-enhanced annihilations and bound-state formation is calculated, incorporating next-to-leading-order corrections and next-to-leading-log resummation of the relevant electroweak effects. In the Milky Way halo, bound-state formation dominates the flux near 100 GeV. The corresponding low-energy spectrum is used to place constraints based on Fermi-LAT observations of Galactic diffuse emission, while the high-energy part of the spectrum is employed to forecast the required observation time for several of the Milky Way's dwarf spheroidal galaxies using the Cherenkov Telescope Array Observatory (CTAO). Fermi-LAT data strongly disfavor the lower edge of the thermal mass window, even under conservative assumptions about the inner Galaxy density profile. Furthermore, several hundred hours of forthcoming CTAO observations of northern dwarfs should be sufficient to probe the central mass value.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"39 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2026-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148460532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

引用次数: 0

Prompt cusps in hierarchical dark matter halos: implications for annihilation boost 等级暗物质晕的提示尖峰：湮灭促进的含义

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2026-07-16 DOI: 10.1088/1475-7516/2026/07/062

Shin'ichiro Ando, Martín Moró González and Youyou Li

{"title":"Prompt cusps in hierarchical dark matter halos: implications for annihilation boost","authors":"Shin'ichiro Ando, Martín Moró González and Youyou Li","doi":"10.1088/1475-7516/2026/07/062","DOIUrl":"https://doi.org/10.1088/1475-7516/2026/07/062","url":null,"abstract":"Recent simulations have identified long-lived “prompt cusps” — compact remnants of early density peaks with inner profiles ρ ∝ r-3/2. They can survive hierarchical assembly and potentially enhance signals of dark matter annihilation. In this work, we incorporate prompt cusps into the semi-analytic substructure framework SASHIMI, enabling a fully hierarchical, environment-dependent calculation of the annihilation luminosity that consistently tracks subhalos, sub-subhalos, and tidal stripping. We assign prompt cusps to first-generation microhalos and propagate their survival through the merger history, including an explicit treatment of cusps associated with stripped substructure. We find that the substructure hierarchy converges rapidly once a few levels are included, and that prompt cusps can raise the total annihilation boost of Milky-Way-size hosts at z = 0 to B ∼ 50 for fiducial cusp-occupation assumptions, compared to a subhalo-only baseline of Bsh ∼ few. Across a wide range of host masses and redshifts, prompt cusps increase the normalization of B(Mhost,z) while largely preserving its mass and redshift trends. Compared to universal-average, peak-based estimates, our fiducial boosts are lower by about a factor of a few, primarily reflecting a correspondingly smaller inferred cusp abundance in host halos, highlighting the importance of unifying peak-based cusp formation with merger-tree evolution and environmental dependence.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"33 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2026-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148460531","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}

引用次数: 0