{"title":"Weighing massive neutrinos with Lyman-α observations","authors":"Anjan Kumar Sarkar and Shiv K. Sethi","doi":"10.1088/1475-7516/2024/09/003","DOIUrl":null,"url":null,"abstract":"The presence of massive neutrinos has still not been revealed by the cosmological data. We consider a novel method based on the two-point line-of-sight correlation function of high-resolution Lyman-α data to achieve this end in the paper. We adopt semi-analytic models of Lyman-α clouds for the study. We employ Fisher matrix technique to show that it is possible to achieve a scenario in which the covariance of the two-point function nearly vanishes for both the spectroscopic noise and the signal. We analyze this near `zero noise' outcome in detail to argue it might be possible to detect neutrinos of mass range mν ≃ 0.05–0.1 eV with signal-to-noise of unity with a single QSO line of sight. We show that this estimate can be improved to SNR ≃ 3–6 with data along multiple line of sights within the redshift range z ≃ 2–2.5. Such data sets already exist in the literature. We further carry out principal component analysis of the Fisher matrix to study the degeneracies of the neutrino mass with other parameters. We show that Planck priors lift the degeneracies between the neutrino mass and other cosmological parameters. However, the prospects of the detection of neutrino mass are driven by the poorly-determined parameters characterizing the ionization and thermal state of Lyman-α clouds. We have also mentioned the possible limitations and observational challenges posed in measuring the neutrino mass using our method.","PeriodicalId":15445,"journal":{"name":"Journal of Cosmology and Astroparticle Physics","volume":null,"pages":null},"PeriodicalIF":5.3000,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Cosmology and Astroparticle Physics","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1088/1475-7516/2024/09/003","RegionNum":2,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ASTRONOMY & ASTROPHYSICS","Score":null,"Total":0}
引用次数: 0
Abstract
The presence of massive neutrinos has still not been revealed by the cosmological data. We consider a novel method based on the two-point line-of-sight correlation function of high-resolution Lyman-α data to achieve this end in the paper. We adopt semi-analytic models of Lyman-α clouds for the study. We employ Fisher matrix technique to show that it is possible to achieve a scenario in which the covariance of the two-point function nearly vanishes for both the spectroscopic noise and the signal. We analyze this near `zero noise' outcome in detail to argue it might be possible to detect neutrinos of mass range mν ≃ 0.05–0.1 eV with signal-to-noise of unity with a single QSO line of sight. We show that this estimate can be improved to SNR ≃ 3–6 with data along multiple line of sights within the redshift range z ≃ 2–2.5. Such data sets already exist in the literature. We further carry out principal component analysis of the Fisher matrix to study the degeneracies of the neutrino mass with other parameters. We show that Planck priors lift the degeneracies between the neutrino mass and other cosmological parameters. However, the prospects of the detection of neutrino mass are driven by the poorly-determined parameters characterizing the ionization and thermal state of Lyman-α clouds. We have also mentioned the possible limitations and observational challenges posed in measuring the neutrino mass using our method.
期刊介绍:
Journal of Cosmology and Astroparticle Physics (JCAP) encompasses theoretical, observational and experimental areas as well as computation and simulation. The journal covers the latest developments in the theory of all fundamental interactions and their cosmological implications (e.g. M-theory and cosmology, brane cosmology). JCAP''s coverage also includes topics such as formation, dynamics and clustering of galaxies, pre-galactic star formation, x-ray astronomy, radio astronomy, gravitational lensing, active galactic nuclei, intergalactic and interstellar matter.