Journal of Cosmology and Astroparticle Physics最新文献_第4页

Non-singular solutions to the Boltzmann equation with a fluid Ansatz 具有流体Ansatz的玻尔兹曼方程的非奇异解

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2025-04-15 DOI: 10.1088/1475-7516/2025/04/033

Gláuber C. Dorsch, Thomas Konstandin, Enrico Perboni and Daniel A. Pinto

{"title":"Non-singular solutions to the Boltzmann equation with a fluid Ansatz","authors":"Gláuber C. Dorsch, Thomas Konstandin, Enrico Perboni and Daniel A. Pinto","doi":"10.1088/1475-7516/2025/04/033","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/04/033","url":null,"abstract":"Cosmological phase transitions can give rise to intriguing phenomena, such as baryogenesis or a stochastic gravitational wave background, due to nucleation and percolation of vacuum bubbles in the primordial plasma. A key parameter for predicting these relics is the bubble wall velocity, whose computation relies on solving the Boltzmann equations of the various species along the bubble profile. Recently it has been shown that an unphysical singularity emerges if one assumes these local quantities to be described as small fluctuations on a constant equilibrium background. In this work we solve this issue by including the spatial dependence of the background into the fluid Ansatz. This leads to a modification of the Boltzmann equation, and all terms that would give rise to a singularity now vanish. We recalculate the different contributions to the counter-pressure of the plasma on the expanding wall, and discuss their relative importance. The Standard Model with a low cutoff is chosen as benchmark model and the results are shown for different values of the cutoff scale Λ. In this setup, deflagration solutions are found for almost all the values of Λ considered, while detonations are found only for some restricted corner of the parameter space.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"3 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143841076","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

SL(2,ℤ) cosmological attractors SL（2, 0）宇宙吸引子

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2025-04-15 DOI: 10.1088/1475-7516/2025/04/045

Renata Kallosh and Andrei Linde

引用次数: 0

BAO vs. SN evidence for evolving dark energy BAO vs. SN暗能量演化的证据

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2025-04-15 DOI: 10.1088/1475-7516/2025/04/048

Alessio Notari, Michele Redi and Andrea Tesi

{"title":"BAO vs. SN evidence for evolving dark energy","authors":"Alessio Notari, Michele Redi and Andrea Tesi","doi":"10.1088/1475-7516/2025/04/048","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/04/048","url":null,"abstract":"We critically review the evidence for time-varying dark energy from recent Baryon Acoustic Oscillations (BAO) and Supernova (SN) observations. First, we show that such evidence is present at the 3σ level, even without the new BAO data from the dark energy Spectroscopic Instrument (DESI), by instead using BAO data from the dark energy Survey (DES), combined with the DES5Y supernovae and Planck CMB data. Next, we examine the role of the DES5Y supernova dataset, showing that the preference for time-varying dark energy is driven by the low redshift supernovae common to both the DES5Y and Pantheon+ compilations. We find that combining Pantheon+ and DES5Y supernovae by removing the common supernovae leads to two different results, depending on whether they are removed from the DES5Y or the Pantheon+ catalog, leading to stronger or weaker exclusion of ΛCDM, at the (3.8σ) and (2.5σ) level, respectively. These common supernovae have smaller error bars in DES5Y compared to Pantheon+, and, as recently pointed out, there is an offset in magnitude in DES5Y between supernovae at (z > 0.1), where almost all the measurements taken during the full five years of DES are, and the low-redshift ones (z < 0.1), where all the historical set of nearby supernovae lies. We show that marginalizing over such an offset in DES5Y would lead to significantly weaker evidence for evolving dark energy.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"24 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143841314","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

Constraining bursty star formation histories with galaxy UV and Hα luminosity functions and clustering 用星系UV和Hα光度函数和聚类来约束恒星爆发的形成历史

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2025-04-15 DOI: 10.1088/1475-7516/2025/04/034

Guochao Sun, Julian B. Muñoz, Jordan Mirocha and Claude-André Faucher-Giguère

{"title":"Constraining bursty star formation histories with galaxy UV and Hα luminosity functions and clustering","authors":"Guochao Sun, Julian B. Muñoz, Jordan Mirocha and Claude-André Faucher-Giguère","doi":"10.1088/1475-7516/2025/04/034","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/04/034","url":null,"abstract":"The observed prevalence of galaxies exhibiting bursty star formation histories (SFHs) at z ≳ 6 has created new challenges and opportunities for understanding their formation pathways. The degenerate effects of the efficiency and burstiness of star formation on the observed UV luminosity function are separable by galaxy clustering. However, quantifying the timescales of burstiness requires more than just the continuum UV measurements. Here we develop a flexible semi-analytic framework for modeling both the amplitude of star formation rate (SFR) variations and their temporal correlation, from which the luminosity function and clustering can be derived for SFR indicators tracing different characteristic timescales (e.g., UV continuum and Hα luminosities). Based on this framework, we study the prospect of using galaxy summary statistics to distinguish models where SFR fluctuations are prescribed by different power spectral density (PSD) forms. Using the Fisher matrix approach, we forecast the constraints on parameters in our PSD-based model that can be extracted from mock JWST observations of the UV and Hα luminosity functions and clustering bias factors at z ∼ 6. If potential confusion due to e.g., dust attenuation and stellar population effects can be properly quantified, these results imply the possibility of probing the burstiness of high-z galaxies with one-point and two-point statistics and highlight the benefits of combining long-term and short-term SFR tracers. Our flexible framework can be readily extended to characterize the SFH of high-redshift galaxies with a wider range of observational diagnostics.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"37 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143841384","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

Parameterized non-circular deviation from the Kerr paradigm and its observational signatures: extreme mass ratio inspirals and Lense-Thirring effect 克尔范式的参数化非圆偏差及其观测特征：极端质量比吸气和Lense-Thirring效应

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2025-04-15 DOI: 10.1088/1475-7516/2025/04/037

Rajes Ghosh and Kabir Chakravarti

{"title":"Parameterized non-circular deviation from the Kerr paradigm and its observational signatures: extreme mass ratio inspirals and Lense-Thirring effect","authors":"Rajes Ghosh and Kabir Chakravarti","doi":"10.1088/1475-7516/2025/04/037","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/04/037","url":null,"abstract":"Recent gravitational wave observations and shadow imaging have demonstrated the astonishing consistency of the Kerr paradigm despite all the special symmetries assumed in deriving the Kerr metric. Hence, it is crucial to test the presence of these symmetries in astrophysical scenarios and constraint possible deviations from them, especially in strong field regimes. With this motivation, the present work aims to investigate the theoretical consequences and observational signatures of non-circularity in a unified theory-agnostic manner. For this purpose, we construct a parametrized non-circular metric with small deviations from Kerr. This metric preserves the other properties of Kerr, such as stationarity, axisymmetry, asymptotic flatness, and the equatorial reflection symmetry. Apart from the resulting mathematical simplifications, this assumption is crucial to disentangle the consequences of relaxing circularity from other properties. Then, after discussing various novel theoretical consequences, we perform a detailed analysis of extreme mass ratio inspirals and Lense-Thirring precession in the context of this newly constructed metric. Our study clearly shows the promising prospects of detecting and constraining even a slight non-circular deviation from the Kerr paradigm using the future gravitational wave observations by the Laser Interferometer Space Antenna.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"1 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143841079","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

Born-Infeld inspired gravity in covariant canonical formalism 玻恩-因菲尔德启发了协变正则形式论中的引力

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2025-04-15 DOI: 10.1088/1475-7516/2025/04/046

J. Klusoň

引用次数: 0

Axion misalignment with memory-burdened PBH 轴子错位与内存负载PBH

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2025-04-15 DOI: 10.1088/1475-7516/2025/04/039

Disha Bandyopadhyay, Debasish Borah and Nayan Das

引用次数: 0

The curvature perturbation generated by thermal fluctuations during thermal inflation 在热膨胀过程中由热波动产生的曲率扰动

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2025-04-15 DOI: 10.1088/1475-7516/2025/04/038

Jeong-Myeong Bae, Hammam Raihan Mohammad, Ewan D. Stewart and Heeseung Zoe

引用次数: 0

Correspondence between quasinormal modes and grey-body factors for massive fields in Schwarzschild-de Sitter spacetime 史瓦西-德西特时空中大质量场的准正态模与灰体因子的对应关系

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2025-04-15 DOI: 10.1088/1475-7516/2025/04/042

Zainab Malik

引用次数: 0

HOD-informed prior for EFT-based full-shape analyses of LSS 基于eft的LSS全形状分析的hod通知先验

IF 6.4 2区物理与天体物理

Journal of Cosmology and Astroparticle Physics Pub Date : 2025-04-15 DOI: 10.1088/1475-7516/2025/04/041

Hanyu Zhang, Marco Bonici, Guido D'Amico, Simone Paradiso and Will J. Percival

{"title":"HOD-informed prior for EFT-based full-shape analyses of LSS","authors":"Hanyu Zhang, Marco Bonici, Guido D'Amico, Simone Paradiso and Will J. Percival","doi":"10.1088/1475-7516/2025/04/041","DOIUrl":"https://doi.org/10.1088/1475-7516/2025/04/041","url":null,"abstract":"To improve the performance of full-shape analyses of large-scale structure, we consider using a halo occupation distribution (HOD)-informed prior for the effective field theory (EFT) nuisance parameters. We generate 320 000 mock galaxy catalogs using 10 000 sets of HOD parameters across 32 simulation boxes with different cosmologies. We measure and fit the redshift-space power spectra using a fast emulator of the EFT model, and the resulting best-fit EFT parameter distributions are used to create the prior. This prior effectively constrains the EFT nuisance parameter space, limiting it to the space of HOD-mocks that can be well fit by a EFT model. We have tested the stability of the prior under different configurations, including the effect of varying the HOD sample distribution and the inclusion of the hexadecapole moment. We find that our HOD-informed prior and the cosmological parameter constraints derived using it are robust. While cosmological fits using the standard EFT prior suffer from prior effects, sometimes failing to recover the true cosmology within Bayesian credible intervals, the HOD-informed prior mitigates these issues and significantly improves cosmological parameter recovery for ΛCDM and beyond. This work lays the foundation for better full-shape large-scale structure analyses in current and upcoming galaxy surveys, making it a valuable tool for addressing key questions in cosmology.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":"11 1","pages":""},"PeriodicalIF":6.4,"publicationDate":"2025-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143841310","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