Journal of Cosmology and Astroparticle Physics最新文献_第9页

A universal constraint on axion non-Abelian dynamics during inflation

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2025-03-06 DOI: 10.1088/1475-7516/2025/03/007

Ema Dimastrogiovanni, Matteo Fasiello, Martino Michelotti and Ogan Özsoy

{"title":"A universal constraint on axion non-Abelian dynamics during inflation","authors":"Ema Dimastrogiovanni, Matteo Fasiello, Martino Michelotti and Ogan Özsoy","doi":"10.1088/1475-7516/2025/03/007","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/03/007","url":null,"abstract":"Inflationary models equipped with Chern-Simons coupling between their axion and gauge sectors exhibit an array of interesting signals including a testable chiral gravitational wave spectrum. The energy injection in the gauge sector triggered by the rolling axion leads to a well-studied enhancement of gauge field fluctuations. These may in turn affect observables such as the scalar and tensor spectra and also account for non-linear corrections to field propagators. In this work, we focus on non-Abelian gauge sectors. We show that gauge field self-interactions and axion-gauge field non-linear couplings significantly renormalize the gauge field mode function. Operating within the regime of validity of the perturbative treatment places strong constraints on the accessible parameter space of this class of models. We calculate corrections to the gauge field propagator that are universally present in these scenarios. Enforcing perturbativity on such propagators leads to bounds that are competitive with those stemming from analytical estimates on the onset of the strong backreaction regime.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"91 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143560806","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

Gravitational waves from dark binaries with finite-range dark forces

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2025-03-06 DOI: 10.1088/1475-7516/2025/03/010

Yang Bai, Sida Lu and Nicholas Orlofsky

引用次数: 0

Gravitational waves from extreme mass ratio inspirals in Kerr-MOG spacetimes

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2025-03-06 DOI: 10.1088/1475-7516/2025/03/006

Xiongying Qiao, Zhong-Wu Xia, Qiyuan Pan, Hong Guo, Wei-Liang Qian and Jiliang Jing

{"title":"Gravitational waves from extreme mass ratio inspirals in Kerr-MOG spacetimes","authors":"Xiongying Qiao, Zhong-Wu Xia, Qiyuan Pan, Hong Guo, Wei-Liang Qian and Jiliang Jing","doi":"10.1088/1475-7516/2025/03/006","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/03/006","url":null,"abstract":"This work elaborates on a detailed analysis of the novel characteristics of gravitational waves (GWs) generated by extreme mass-ratio inspirals (EMRIs) within the framework of modified gravity (MOG). Our study begins by exploring the geometrical and dynamical properties of the Kerr-MOG spacetime. We employ the numerical kludge (NK) method for waveform simulations and reveal that the parameter α, representing deviations from general relativity (GR), significantly impacts the frequencies of geodesic orbits and, consequently, the EMRI waveforms. However, the waveform confusion problem remains mainly unresolved, posing a challenge in distinguishing between the underlying gravitational theories based on the observed EMRI waveforms. Notably, by incorporating the effects of radiation reaction and increasing the MOG parameter α, we observe a substantial reduction in the waveform overlap over time. This reduction could enhance our ability to discern between different waveforms over an extended period. Our analysis further identifies that α begins to influence energy fluxes at the 1 post-Newtonian (PN) order, highlighting its leading-order effects on the orbital dynamics. Additionally, we find that α becomes detectable when the estimated overlap crosses the detection threshold by computing the mismatch. And we estimate that the detection error for α can be constrained to Δα ≈ 1.85 × 10-4 by using the Fisher information matrix (FIM) method, demonstrating the potential of space-based gravitational wave detectors to probe deviations from GR with high precision.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"2 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143560804","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 vanishing of the non-linear static love number of Kerr black holes and the role of symmetries 克尔黑洞非线性静态爱数的消失和对称性的作用

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2025-03-04 DOI: 10.1088/1475-7516/2025/03/002

L.-R. Gounis, A. Kehagias and A. Riotto

引用次数: 0

Extracting axion string network parameters from simulated CMB birefringence maps using convolutional neural networks 利用卷积神经网络从模拟 CMB 双折射图中提取轴弦网络参数

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2025-03-04 DOI: 10.1088/1475-7516/2025/03/001

Ray Hagimoto, Andrew J. Long and Mustafa A. Amin

{"title":"Extracting axion string network parameters from simulated CMB birefringence maps using convolutional neural networks","authors":"Ray Hagimoto, Andrew J. Long and Mustafa A. Amin","doi":"10.1088/1475-7516/2025/03/001","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/03/001","url":null,"abstract":"Axion-like particles may form a network of cosmic strings in the Universe today that can rotate the plane of polarization of cosmic microwave background (CMB) photons. Future CMB observations with improved sensitivity might detect this axion-string-induced birefringence effect, thereby revealing an as-yet unseen constituent of the Universe and offering a new probe of particles and forces that are beyond the Standard Model of Elementary Particle Physics. In this work, we explore how spherical convolutional neural networks (SCNNs) may be used to extract information about the axion string network from simulated birefringence maps. We construct a pipeline to simulate the anisotropic birefringence that would arise from an axion string network, and we train SCNNs to estimate three parameters related to the cosmic string length, the cosmic string abundance, and the axion-photon coupling. Our results demonstrate that neural networks are able to extract information from a birefringence map that is inaccessible with two-point statistics alone (i.e., the angular power spectrum). We also assess the impact of noise on the accuracy of our SCNN estimators, demonstrating that noise at the level anticipated for Stage IV (CMB-S4) measurements would significantly bias parameter estimation for SCNNs trained on noiseless simulated data, and necessitate modeling the noise in the training data.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"34 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143538617","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

Cherenkov Telescope Array Observatory sensitivity to heavy Galactic Cosmic Rays and the shape of particle spectrum

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2025-02-28 DOI: 10.1088/1475-7516/2025/02/078

C. Dubos, P. Sharma, S. Patel and T. Suomijärvi

{"title":"Cherenkov Telescope Array Observatory sensitivity to heavy Galactic Cosmic Rays and the shape of particle spectrum","authors":"C. Dubos, P. Sharma, S. Patel and T. Suomijärvi","doi":"10.1088/1475-7516/2025/02/078","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/02/078","url":null,"abstract":"The origin of Galactic Cosmic Rays (GCRs) and the potential role of Supernova Remnants (SNRs) as cosmic-ray (CR) accelerators remain subjects of ongoing debate. To shed more light on this topic, we have studied the spectral shapes of two SNRs, RX J1713.7-3946 and HAWC J2227+610, performing simulations for the Cherenkov Telescope Array Observatory (CTAO). The previous multi-wavelength (MWL) analysis on these two sources showed an important hadronic contribution at high energies. The interaction of the GCRs accelerated by the SNRs with the medium around the accelerator leads to a process of pion decay (PD) that produces gamma-rays (γ-rays). These emissions, detectable by CTAO, offer an indirect means of pinpointing the CR source. Two scenarios have been considered: the contribution of heavy CRs and different cut-off sharpnesses (β) of the particle spectra. The simulations were performed by using different CR composition distributions (protons, CNO, Fe) and different sharpness values ranging from β = 0.5 to β = 1.5. The results show that, in the cases studied here, CTAO will increase the sensitivity to the spectral shape of γ-rays. This allows us to distinguish protons from heavy CRs and obtain information on β values and therefore on different acceleration scenarios.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"11 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143518543","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

Light from darkness: history of a hot dark sector

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2025-02-28 DOI: 10.1088/1475-7516/2025/02/077

Rupert Coy, Jean Kimus and Michel H.G. Tytgat

{"title":"Light from darkness: history of a hot dark sector","authors":"Rupert Coy, Jean Kimus and Michel H.G. Tytgat","doi":"10.1088/1475-7516/2025/02/077","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/02/077","url":null,"abstract":"We study a scenario in which the expansion of the Early Universe is driven by a hot hidden sector (HS) with an initial temperature T' that is significantly higher than that of the visible sector (VS), T' ≫ T. The latter is assumed to be made of Standard Model (SM) particles and our main focus is on the possibility that dark matter (DM) is part of the dominant HS and that its abundance is set by secluded freeze-out. In particular, we study the subsequent evolution and fate of the DM companion particle after freeze-out all the way toward reheating of the VS. To make this scenario more concrete, we work within dark QED, a framework in which the DM is a Dirac fermion and its companion, a massive dark photon; coupling between the SM and HS is through kinetic mixing. We provide a detailed and comprehensive numerical and analytical analysis of the different regimes of reheating of the VS. Extending and complementing the work of Coy et al. on the“domain of thermal dark matter candidates” [1], we use our results to explore the viable parameter space of both the DM matter particle and its companion, here the dark photon. We show that current and future fixed target experiments can probe scenarios along which the expansion was driven by relativistic DM photons, a scenario dubbed relativistic reheating. We also set new bounds on the maximal temperature ratio T'/T and argue for an extension of the domain toward very large DM masses, mdm ∼ 1011 GeV. These are possible assuming that DM annihilation is bounded by unitarity and that reheating of the VS occurs just before big bang nucleosynthesis. We also discuss some possible implications for (and constraints on) baryogenesis, including simple leptogenesis mechanisms, and how they may set additional constraints on the domain of DM candidates.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"70 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-02-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143518024","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

Cosmological gravity on all scales. Part IV. 3× 2 pt Fisher forecasts for pixelised phenomenological modified gravity

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2025-02-27 DOI: 10.1088/1475-7516/2025/02/071

Sankarshana Srinivasan, Daniel B. Thomas and Peter L. Taylor

{"title":"Cosmological gravity on all scales. Part IV. 3× 2 pt Fisher forecasts for pixelised phenomenological modified gravity","authors":"Sankarshana Srinivasan, Daniel B. Thomas and Peter L. Taylor","doi":"10.1088/1475-7516/2025/02/071","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/02/071","url":null,"abstract":"Stage-IV large scale structure surveys are promising probes of gravity on cosmological scales. Due to the vast model-space in the modified gravity literature, model-independent parameterisations represent useful and scalable ways to test extensions of ΛCDM. In this work we use a recently validated approach of computing the non-linear 3 × 2 pt observables in modified gravity models with a time-varying effective gravitational constant μ and a gravitational slip η that is binned in redshift to produce Fisher forecasts for an LSST Y10-like survey. We also include in our modelling an effective nulling scheme for weak-lensing by applying the Bernardeau-Nishimichi-Taruya (BNT) transformation that localises the weak-lensing kernel enabling well-informed scale cuts. We show that the combination of improved non-linear modelling and better control of the scales that are modelled/cut yields high precision constraints on the cosmological and modified gravity parameters. We find that 4 redshift bins for μ of width corresponding to equal incremental ΛCDM growth is optimal given the state-of-the-art modelling and show how the BNT transformation can be used to mitigate the impact of small-scale systematic effects, such as baryonic feedback.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"54 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143518028","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

Impact of low ell's on large scale structure anomalies

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2025-02-27 DOI: 10.1088/1475-7516/2025/02/069

Ido Ben-Dayan, Utkarsh Kumar, Meir Shimon and Amresh Verma

引用次数: 0

Gravitational lensing of neutrinos in parametrized black hole spacetimes

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2025-02-27 DOI: 10.1088/1475-7516/2025/02/070

Mirzabek Alloqulov, Hrishikesh Chakrabarty, Daniele Malafarina, Bobomurat Ahmedov and Ahmadjon Abdujabbarov

引用次数: 0