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Author D'Eramo, F.; Di Valentino, E.; Giare, W.; Hajkarim, F.; Melchiorri, A.; Mena, O.; Renzi, F.; Yun, S.
Title Cosmological bound on the QCD axion mass, redux Type Journal Article
Year (down) 2022 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 09 Issue 9 Pages 022 - 35pp
Keywords axions; cosmology of theories beyond the SM; cosmological neutrinos; neutrino masses from cosmology
Abstract We revisit the joint constraints in the mixed hot dark matter scenario in which both thermally produced QCD axions and relic neutrinos are present. Upon recomputing the cosmological axion abundance via recent advances in the literature, we improve the state-of-the-art analyses and provide updated bounds on axion and neutrino masses. By avoiding approximate methods, such as the instantaneous decoupling approximation, and limitations due to the limited validity of the perturbative approach in QCD that forced to artificially divide the constraints from the axion-pion and the axion-gluon production channels, we find robust and self-consistent limits. We investigate the two most popular axion frameworks: KSVZ and DFSZ. From Big Bang Nucleosynthesis (BBN) light element abundances data we find for the KSVZ axion Delta N-eff < 0.31 and an axion mass bound m(a) < 0.53 eV (i.e., a bound on the axion decay constant f(a) > 1.07 x 10(7) GeV) both at 95% CL. These BBN bounds are improved to Delta N-eff < 0.14 and m(a) < 0.16 eV (f(a) > 3.56 x 10(7) GeV) if a prior on the baryon energy density from Cosmic Microwave Background (CMB) data is assumed. When instead considering cosmological observations from the CMB temperature, polarization and lensing from the Planck satellite combined with large scale structure data we find Delta N-eff < 0.23, m(a) < 0.28 eV (f(a) > 2.02 x 10(7) GeV) and Sigma m(nu) < 0.16 eV at 95% CL. This corresponds approximately to a factor of 5 improvement in the axion mass bound with respect to the existing limits. Very similar results are obtained for the DFSZ axion. We also forecast upcoming observations from future CMB and galaxy surveys, showing that they could reach percent level errors for m(a) similar to 1 eV.
Address [D'Eramo, Francesco; Hajkarim, Fazlollah; Yun, Seokhoon] Univ Padua, Dipartimento Fis & Astron, Via Marzolo 8, I-35131 Padua, Italy, Email: francesco.deramo@pd.infn.it;
Corporate Author Thesis
Publisher IOP Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000863296000010 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5383
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Author Gariazzo, S.; Gerbino, M.; Brinckmann, T.; Lattanzi, M.; Mena, O.; Schwetz, T.; Choudhury, S.R.; Freese, K.; Hannestad, S.; Ternes, C.A.; Tortola, M.
Title Neutrino mass and mass ordering: no conclusive evidence for normal ordering Type Journal Article
Year (down) 2022 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 10 Issue 10 Pages 010 - 18pp
Keywords Bayesian reasoning; neutrino properties; neutrino masses from cosmology; cosmological parameters from CMBR
Abstract The extraction of the neutrino mass ordering is one of the major challenges in particle physics and cosmology, not only for its implications for a fundamental theory of mass generation in nature, but also for its decisive role in the scale of future neutrinoless double beta decay experimental searches. It has been recently claimed that current oscillation, beta decay and cosmological limits on the different observables describing the neutrino mass parameter space provide robust decisive Bayesian evidence in favor of the normal ordering of the neutrino mass spectrum [1]. We further investigate these strong claims using a rich and wide phenomenology, with different sampling techniques of the neutrino parameter space. Contrary to the findings of Jimenez et al. [1], no decisive evidence for the normal mass ordering is found. Neutrino mass ordering analyses must rely on priors and parameterizations that are ordering-agnostic: robust results should be regarded as those in which the preference for the normal neutrino mass ordering is driven exclusively by the data, while we find a difference of up to a factor of 33 in the Bayes factors among the different priors and parameterizations exploited here. An ordering-agnostic prior would be represented by the case of parameterizations sampling over the two mass splittings and a mass scale, or those sampling over the individual neutrino masses via normal prior distributions only. In this regard, we show that the current significance in favor of the normal mass ordering should be taken as 2.7 sigma (i.e. moderate evidence), mostly driven by neutrino oscillation data. Let us stress that, while current data favor NO only mildly, we do not exclude the possibility that this may change in the future. Eventually, upcoming oscillation and cosmological data may (or may not) lead to a more significant exclusion of IO.
Address [Gariazzo, Stefano; Ternes, Christoph A.] Ist Nazl Fis Nucl INFN, Sez Torino, Via P Giuria 1, I-10125 Turin, Italy, Email: gariazzo@to.infn.it;
Corporate Author Thesis
Publisher IOP Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000928487200002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5477
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Author Villanueva-Domingo, P.; Villaescusa-Navarro, F.
Title Removing Astrophysics in 21 cm Maps with Neural Networks Type Journal Article
Year (down) 2021 Publication Astrophysical Journal Abbreviated Journal Astrophys. J.
Volume 907 Issue 1 Pages 44 - 14pp
Keywords Cosmology; Cold dark matter; Dark matter; Dark matter distribution; H I line emission; Intergalactic medium; Cosmological evolution; Convolutional neural networks; Large-scale structure of the universe
Abstract Measuring temperature fluctuations in the 21 cm signal from the epoch of reionization and the cosmic dawn is one of the most promising ways to study the universe at high redshifts. Unfortunately, the 21 cm signal is affected by both cosmology and astrophysics processes in a nontrivial manner. We run a suite of 1000 numerical simulations with different values of the main astrophysical parameters. From these simulations we produce tens of thousands of 21 cm maps at redshifts 10 <= z <= 20. We train a convolutional neural network to remove the effects of astrophysics from the 21 cm maps and output maps of the underlying matter field. We show that our model is able to generate 2D matter fields not only that resemble the true ones visually but whose statistical properties agree with the true ones within a few percent down to scales 2 Mpc(-1). We demonstrate that our neural network retains astrophysical information that can be used to constrain the value of the astrophysical parameters. Finally, we use saliency maps to try to understand which features of the 21 cm maps the network is using in order to determine the value of the astrophysical parameters.
Address [Villanueva-Domingo, Pablo] Univ Valencia, Inst Fis Corpuscular IFIC, CSIC, Apartado Correos 22085, E-46071 Valencia, Spain, Email: Pablo.Villanueva@ific.uv.es;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0004-637x ISBN Medium
Area Expedition Conference
Notes WOS:000612333400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4698
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Author Bloch, I.M.; Caputo, A.; Essig, R.; Redigolo, D.; Sholapurkar, M.; Volansky, T.
Title Exploring new physics with O(keV) electron recoils in direct detection experiments Type Journal Article
Year (down) 2021 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 01 Issue 1 Pages 178 - 63pp
Keywords Beyond Standard Model; Cosmology of Theories beyond the SM
Abstract Motivated by the recent XENON1T results, we explore various new physics models that can be discovered through searches for electron recoils in O(keV)-threshold direct-detection experiments. First, we consider the absorption of axion-like particles, dark photons, and scalars, either as dark matter relics or being produced directly in the Sun. In the latter case, we find that keV mass bosons produced in the Sun provide an adequate fit to the data but are excluded by stellar cooling constraints. We address this tension by introducing a novel Chameleon-like axion model, which can explain the excess while evading the stellar bounds. We find that absorption of bosonic dark matter provides a viable explanation for the excess only if the dark matter is a dark photon or an axion. In the latter case, photophobic axion couplings are necessary to avoid X-ray constraints. Second, we analyze models of dark matter-electron scattering to determine which models might explain the excess. Standard scattering of dark matter with electrons is generically in conflict with data from lower-threshold experiments. Momentum-dependent interactions with a heavy mediator can fit the data with dark matter mass heavier than a GeV but are generically in tension with collider constraints. Next, we consider dark matter consisting of two (or more) states that have a small mass splitting. The exothermic (down)scattering of the heavier state to the lighter state can fit the data for keV mass splittings. Finally, we consider a subcomponent of dark matter that is accelerated by scattering off cosmic rays, finding that dark matter interacting though an O(100 keV)-mass mediator can fit the data. The cross sections required in this scenario are, however, typically challenged by complementary probes of the light mediator. Throughout our study, we implement an unbinned Monte Carlo analysis and use an improved energy reconstruction of the XENON1T events.
Address [Bloch, Itay M.; Volansky, Tomer] Tel Aviv Univ, Sch Phys & Astron, IL-69978 Tel Aviv, Israel, Email: itay.bloch.m@gmail.com;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000616257000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4713
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Author Mosbech, M.R.; Boehm, C.; Hannestad, S.; Mena, O.; Stadler, J.; Wong, Y.Y.Y.
Title The full Boltzmann hierarchy for dark matter-massive neutrino interactions Type Journal Article
Year (down) 2021 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 03 Issue 3 Pages 066 - 31pp
Keywords cosmological perturbation theory; dark matter theory; neutrino properties; particle physics – cosmology connection
Abstract The impact of dark matter-neutrino interactions on the measurement of the cosmological parameters has been investigated in the past in the context of massless neutrinos exclusively. Here we revisit the role of a neutrino-dark matter coupling in light of ongoing cosmological tensions by implementing the full Boltzmann hierarchy for three massive neutrinos. Our tightest 95% CL upper limit on the strength of the interactions, parameterized via u(chi) = sigma(0)/sigma(Th) (m(chi)/100GeV)(-1), is u(chi) <= 3.34 . 10(-4), arising from a combination of Planck TTTEEE data, Planck lensing data and SDSS BAO data. This upper bound is, as expected, slightly higher than previous results for interacting massless neutrinos, due to the correction factor associated with neutrino masses. We find that these interactions significantly relax the lower bounds on the value of sigma 8 that is inferred in the context of Lambda CDM from the Planck data, leading to agreement within 1-2 sigma with weak lensing estimates of sigma 8, as those from KiDS1000. However, the presence of these interactions barely affects the value of the Hubble constant H-0.
Address [Mosbech, Markus R.; Boehm, Celine] Univ Sydney, Sch Phys, Camperdown, NSW 2006, Australia, Email: mmos6302@uni.sydney.edu.au;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000636717400061 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4783
Permanent link to this record