Journal of Cosmology and Astroparticle Physics最新文献

{"title":"Radiation exposure from the dark","authors":"Florian Niedermann and Martin S. Sloth","doi":"10.1088/1475-7516/2025/05/042","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/05/042","url":null,"abstract":"We explore the possibility that exotic forms of dark matter could expose humans on Earth or on prolonged space travel to a significant radiation dose. The radiation exposure from dark matter interacting with nuclei in the human body is generally assumed to be negligible compared to other sources of background radiation. However, as we discuss here, current data allow for dark matter models where this is not necessarily true. In particular, if dark matter is heavier and more strongly interacting than weakly interacting massive particle dark matter, it could act as ionizing radiation and deposit a significant amount of radiation energy in all or part of the human population, similar to or even exceeding the known radiation exposure from other background sources. Conversely, the non-observation of such an exposure can be used to constrain this type of heavier and more strongly interacting dark matter. We first consider the case where dark matter scatters elastically and identify the relevant parameter space in a model-independent way. We also discuss how previous bounds from cosmological probes, as well as atmospheric and space-based detectors, might be avoided, and how a re-analysis of existing radiation data, along with a simple experiment monitoring ionizing radiation in space with a lower detection threshold, could help constrain part of this parameter space. We finally propose a hypothetical dark matter candidate that scatters inelastically and argue that, in principle, one per mille of the Earth's population could attain a significant radiation dose from such a dark matter exposure in their lifetime.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"4 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144066464","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}

{"title":"Revisiting van Citter-Zernike correlations in the presence of primordial gravitational waves","authors":"F. Shojaei Arani, M. Bagheri Harouni, Brahim Lamine and Alain Blanchard","doi":"10.1088/1475-7516/2025/05/032","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/05/032","url":null,"abstract":"In this paper, we develop a quantum field theory framework to describe the interaction between a gravitational wave (GW) background and an electromagnetic (EM) field emitted from a distant celestial source, such as a star. We demonstrate that a background of primordial gravitational waves (PGWs), as predicted by the inflationary scenario, induces a loss of spatial coherence in the EM field as it propagates over cosmological distances. This effect leads to the degradation of van Cittert-Zernike correlations, ultimately rendering them unobservable — a phenomenon referred to as blurring. Since spatial coherence is observed in very long baseline interferometry (VLBI) measurements of distant quasars, this places constraints on the amplitude of the PGW background. We quantitatively evaluate the blurring effect caused by PGWs in a two-mode squeezed state, which represents the standard quantum state predicted by the simplest inflationary models. However, due to the weak coupling between GWs and the EM field, we find that the induced incoherence is too small to be detected in current VLBI observations.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"114 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143945819","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}

{"title":"Detection prospects for the GW background of galactic (sub)solar mass primordial black holes","authors":"Frans van Die, Ivan Rapoport, Yonadav Barry Ginat and Vincent Desjacques","doi":"10.1088/1475-7516/2025/05/036","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/05/036","url":null,"abstract":"In multi-component dark matter models, a fraction fpbh of the dark matter could be in the form of primordial black holes (PBHs) with (sub)solar masses. Some would have formed binaries that presently trace the Milky Way halo of particle dark matter. We explore the gravitational wave (GW) signal produced by such a hypothetical population of Galactic PBH binaries and assess its detectability by the LISA experiment. For this purpose, we model the formation and evolution of early-type PBH binaries accounting for GW hardening and binary disruption in the Milky Way. Our analysis reveals that the present-day Galactic population of PBH binaries is characterized by very high orbital eccentricities |1-e| ≪ 1. For a PBH mass Mpbh ∼ 0.1 - 1M⊙, this yields a GW background that peaks in the millihertz frequency range where the LISA instrumental noise is minimum. While this signal remains below the LISA detection threshold for viable fpbh ≲ 0.01, future GW observatories such as DECIGO and BBO could detect it if 0.01 ≲ Mpbh ≲ 0.1M⊙. Furthermore, we anticipate that, after 5 years of observations, LISA should be able to detect 𝒪(100) (resp. 𝒪(1)) loud Galactic PBH binaries of mass Mpbh ≲ 0.1 - 1M⊙ with a SNR ≥ 5 if fpbh = 0.01 (resp. fpbh = 0.001). Nonlinear effects not considered here such as mass accretion and dynamical capture could alter these predictions.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"8 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143945586","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}

{"title":"Radio lines from accreting axion stars","authors":"Dennis Maseizik, Sagnik Mondal, Hyeonseok Seong and Günter Sigl","doi":"10.1088/1475-7516/2025/05/033","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/05/033","url":null,"abstract":"Axion-like particles, which we call axions, can compose the missing dark matter and may form substructures such as miniclusters and axion stars. We obtain the mass distributions of axion stars derived from their host miniclusters in our galaxy and find a significant number of axion stars reaching the decay mass, the critical mass set by the axion-photon coupling. Axion stars that have reached the decay mass can accrete surrounding axions either via or directly from their host miniclusters, subsequently converting them into radio photons through parametric resonance. We demonstrate that this accretion provides observable signals by proposing two scenarios: 1) external accretion of background dark matter occurring via miniclusters, and 2) internal accretion of isolated systems occurring directly from the minicluster onto its core. The emitted radio photons are nearly monochromatic with energies around the half of the axion mass. The radio-line signal emanating from such axion stars provides a distinctive opportunity searching for axions, overcoming the widespread radio backgrounds. We estimate the expected radio-line flux density to constrain the axion-photon coupling g_aγγ at each axion mass and find that the resultant line flux density is strong enough to be observed in radio telescopes such as LOFAR, FAST, ALMA, and upcoming SKA. We can constrain the axion-photon coupling down to gaγγ ≃ 10-12–10-11 GeV-1, reaching even 10-13 GeV-1 depending on the accretion models of axion stars, over an axion mass range of ma ≃ 10-7–10-2 eV. From a different perspective, this radio-line signal could be a strong hint of an axion at the corresponding mass and also of axion stars within our galaxy.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"8 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143945734","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}

{"title":"Prospecting bipartite dark matter through gravitational waves","authors":"Pankaj Borah, Pradipta Ghosh and Abhijit Kumar Saha","doi":"10.1088/1475-7516/2025/05/035","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/05/035","url":null,"abstract":"We explore the gravitational wave probes of a two-component dark matter framework, consisting of an SU(2)L triplet scalar and a Standard Model singlet fermion. The triplet scalar dark matter typically remains underabundant in the region below ∼ 1.9 TeV, due to the strong SU(2)L gauge mediated interactions. We introduce a second dark matter component, an SU(2)L singlet vector-like Dirac fermion, to address this deficit in the dark matter relic abundance within a sub-TeV range. A key aspect of the proposed setup is the potential dark matter inter-conversion between the two components, which impacts the dark matter freeze-out dynamics and relic density of individual dark matter components. In such a scenario, we examine the properties of electroweak phase transition and identify the regions of parameter space that exhibit strong first-order phase transition. We estimate the resulting gravitational wave spectrum and its detectability, which could be probed through the conventional power-law-integrated sensitivity limits and the recently proposed peak-integrated sensitivity curves. Our analysis reveals that a novel region of the model's parameter space, compatible with dark matter observables, can generate a detectable gravitational wave spectrum, observable by upcoming space-based gravitational wave detectors such as LISA, BBO, DECIGO, and DECIGOcorr, while also offering complementary detection prospects in the dark matter and collider experiments.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"25 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143945736","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}

{"title":"Global 21 cm signal: a promising probe of primordial features","authors":"Suvedha Suresh Naik, Pravabati Chingangbam, Saurabh Singh, Andrei Mesinger and Kazuyuki Furuuchi","doi":"10.1088/1475-7516/2025/05/038","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/05/038","url":null,"abstract":"Inflationary models that involve bursts of particle production generate bump-like features in the primordial power spectrum of density perturbations. These features influence the evolution of density fluctuations, leaving their unique signatures in cosmological observations. A detailed investigation of such signatures would help constrain physical processes during inflation. With this motivation, the goal of this paper is two-fold. First, we conduct a detailed analysis of the effects of bump-like primordial features on the sky-averaged 21 cm signal. Using semi-numerical simulations, we demonstrate that the primordial features can significantly alter the ionization history and the global 21 cm profile, making them a promising probe of inflationary models. We found a special scale (namely, the turnover wavenumber, kturn) at which the effect of primordial bump-like features on the global 21 cm profile vanishes. Also, we found that the behaviour of the primordial features on the global profile and ionization history are quite opposite for k > kturn and k < kturn. We trace the root cause of these behaviours to the effects of primordial features on the halo mass function at high redshifts. Furthermore, we discuss the degeneracy between the astrophysical parameters and the primordial features in detail. Secondly, for a fixed set of astrophysical parameters, we derive upper limits on the amplitude of bump-like features in the range 10-1 < k [ Mpc^-1] < 102 using current limits on optical depth to reionization from CMB data by Planck.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"77 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143945738","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}

{"title":"Landscape of modular cosmology","authors":"Renata Kallosh and Andrei Linde","doi":"10.1088/1475-7516/2025/05/037","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/05/037","url":null,"abstract":"We investigate the global structure of the recently discovered family of SL(2,ℤ)-invariant potentials describing inflationary α-attractors. These potentials have an inflationary plateau consisting of the fundamental domain and its images fully covering the upper part of the Poincaré half-plane. Meanwhile, the lower part of the half-plane is covered by an infinitely large number of ridges, which, at first glance, are too sharp to support inflation. However, we show that this apparent sharpness is just an illusion created by hyperbolic geometry, and each of these ridges is physically equivalent to the inflationary plateau in the upper part of the Poincaré half-plane.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"29 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143946084","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}

{"title":"Robustness of dark energy phenomenology across different parameterizations","authors":"William J. Wolf, Carlos García-García and Pedro G. Ferreira","doi":"10.1088/1475-7516/2025/05/034","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/05/034","url":null,"abstract":"The recent evidence for dynamical dark energy from DESI, in combination with other cosmological data, has generated significant interest in understanding the nature of dark energy and its underlying microphysics. However, interpreting these results critically depends on how dark energy is parameterized. This paper examines the robustness of conclusions about the viability of particular kinds of dynamical dark energy models to the choice of parameterization, focusing on four popular two-parameter families: the Chevallier-Polarski-Linder (CPL), Jassal-Bagla-Padmanabhan (JBP), Barboza-Alcaniz (BA), and exponential (EXP) parameterizations. We find that conclusions regarding the viability of minimally and non-minimally coupled quintessence models are independent of the parameterization adopted. We demonstrate this both by mapping these dark energy models into the (w0, wa) parameter space defined by these various parameterizations and by showing that all of these parameterizations can equivalently account for the phenomenology predicted by these dark energy models to a high degree of accuracy.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"231 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143945735","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}

{"title":"Selection of high-redshift Lyman-Break Galaxies from broadband and wide photometric surveys","authors":"Constantin Payerne, William d'Assignies Doumerg, Christophe Yèche, Vanina Ruhlmann-Kleider, Anand Raichoor, Dusting Lang, Jessica Nicole Aguilar, Steven Ahlen, Stéphane Arnouts, Davide Bianchi, David Brooks, Todd Claybaugh, Shaun Cole, Axel de la Macorra, Arjun Dey, Biprateep Dey, Peter Doel, Andreu Font-Ribera, Jaime E. Forero-Romero, Satya Gontcho A. Gontcho, Gaston Gutierrez, Stephen Gwyn, Klaus Honscheid, Stephanie Juneau, Andrew Lambert, Martin Landriau, Laurent Le Guillou, Michael E. Levi, Christophe Magneville, Marc Manera, Aaron Meisner, Ramon Miquel, John Moustakas, Jeffrey A. Newman, Nathalie Palanque-Delabrouille, Will Percival, Vincent Picouet, Francisco Prada, Ignasi Pérez-Ràfols, Graziano Rossi, Eusebio Sanchez, Marcin Sawicki, David Schlegel, Michael Schubnell, David Sprayberry, Gregory Tarlé, Benjamin A. Weaver and Hu Zou","doi":"10.1088/1475-7516/2025/05/031","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/05/031","url":null,"abstract":"In this paper, we investigate the possibility of selecting high-redshift Lyman-Break Galaxies (LBG) using current and future broadband wide photometric surveys, such as the Ultraviolet Near Infrared Optical Northern Survey (UNIONS) or the Vera C. Rubin Legacy Survey of Space and Time (LSST), using a Random Forest algorithm. This work is conducted in the context of future large-scale structure spectroscopic surveys like DESI-II, the next phase of the Dark Energy Spectroscopic Instrument (DESI), which will start around 2029. We use deep imaging data from the Hyper Suprime Camera (HSC) and the Canada-France-Hawaii Telescope Large Area U-band Deep Survey (CLAUDS) on the COSMOS and XMM-LSS fields. To predict the selection performance of LBGs with image quality similar to UNIONS, we degrade the u,g,r,i and z bands to UNIONS depth. The Random Forest algorithm is trained with the u,g,r,i and z bands to classify LBGs in the 2.5 < z < 3.5 range. We find that fixing a target density budget of 1,100 deg-2, the Random Forest approach gives a density of z > 2 targets of 873 deg-2, and a density of 493 deg-2 of confirmed LBGs after spectroscopic confirmation with DESI. This UNIONS-like selection was tested in a dedicated spectroscopic observation campaign of 1,000 targets with DESI on the COSMOS field, providing a safe spectroscopic sample with a mean redshift of 3. This sample is used to derive forecasts for DESI-II, assuming a sky coverage of 5,000 deg2. We predict uncertainties on Alcock-Paczynski parameters α⊥ and α∥ to be 0.7% and 1% for 2.6 < z < 3.2, resulting in a potential 2% measurement of the dark energy fraction at high redshift. Additionally, we estimate the uncertainty in local non-Gaussianity and predict σfNL ≈ 7, which would be comparable to the current best precision achieved by Planck. The latter forecast suggests that achieving the precision required to place stringent constraints on inflationary models (σfNL ≈ 1) using spectroscopic galaxy surveys necessitates the development of a next-generation (Stage V) spectroscopic survey.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"38 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143939810","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}

{"title":"Cuscuton bounce beyond the linear regime: bispectrum and strong coupling constraints","authors":"Amir Dehghani, Ghazal Geshnizjani and Jerome Quintin","doi":"10.1088/1475-7516/2025/05/026","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/05/026","url":null,"abstract":"Cuscuton Gravity is characterized as a scalar field that can be added to general relativity without introducing any new dynamical degrees of freedom on a cosmological background. Yet, it modifies gravity such that spacetime singularities can be avoided. This has led to the Cuscuton bounce, a nonsingular cosmology that has been shown to be linearly stable, which is a rare feat. Upon introducing mechanisms known to generate a near-scale-invariant power spectrum of isocurvature perturbations in the prebounce contracting phase, we perform an extensive linear analysis of all scalar perturbations as they evolve through the Cuscuton bounce, both analytically and numerically. Then, after deriving the third-order perturbed action for our theory, we compare the magnitude of its terms (on shell) to those in the second-order action. We show that perturbativity is maintained in the infrared throughout the evolution, including through the bounce. In the ultraviolet, we show that a hierarchy of scales is maintained, with the strong coupling scale well above the relevant background energy scale at all times. We reconfirm these results by computing the three-point functions in various limits and demonstrate that the models do not have any strong coupling problems and furthermore that there is negligible non-Gaussianities on observable scales. Consequently, the primary potential source of observable non-Gaussianities may only arise from the conversion of isocurvature perturbations to curvature perturbations. The whole scenario is thus a robust, stable, weakly coupled nonsingular cosmological model, consistent with observations.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"124 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-05-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143939845","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}