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Author (up) Villanueva-Domingo, P.; Ichiki, K.
Title 21 cm forest constraints on primordial black holes Type Journal Article
Year 2023 Publication Publications of the Astronomical Society of Japan Abbreviated Journal Publ. Astron. Soc. Jpn.
Volume 75 Issue SP1 Pages S33-S49
Keywords dark matter; radio lines: ISM
Abstract Primordial black holes (PBHs) as part of the dark matter (DM) would modify the evolution of large-scale structures and the thermal history of the universe. Future 21 cm forest observations, sensitive to small scales and the thermal state of the intergalactic medium (IGM), could probe the existence of such PBHs. In this article, we show that the shot noise isocurvature mode on small scales induced by the presence of PBHs can enhance the amount of low-mass halos, or minihalos, and thus, the number of 21 cm absorption lines. However, if the mass of PBHs is as large as M-PBH greater than or similar to 10 M-circle dot, with an abundant enough fraction of PBHs as DM, f(PBH), the IGM heating due to accretion on to the PBHs counteracts the enhancement due to the isocurvature mode, reducing the number of absorption lines instead. The concurrence of both effects imprints distinctive signatures on the number of absorbers, allowing the abundance of PBHs to be bound. We compute the prospects for constraining PBHs with future 21 cm forest observations, finding achievable competitive upper limits on the abundance as low as f(PBH) similar to 10(-3) at M-PBH = 100 M-circle dot, or even lower at larger masses, in regions of the parameter space unexplored by current probes. The impact of astrophysical X-ray sources on the IGM temperature is also studied, which could potentially weaken the bounds.
Address [Villanueva-Domingo, Pablo] Univ Valencia, Inst Fis Corpuscular IFIC, CSIC, Apartado Correos 22085, E-46071 Valencia, Spain, Email: ichiki@a.phys.nagoya-u.ac.jp
Corporate Author Thesis
Publisher Oxford Univ Press Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0004-6264 ISBN Medium
Area Expedition Conference
Notes WOS:000768441900001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5168
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Author (up) Villanueva-Domingo, P.; Mena, O.; Palomares-Ruiz, S.
Title A Brief Review on Primordial Black Holes as Dark Matter Type Journal Article
Year 2021 Publication Frontiers in Astronomy and Space Sciences Abbreviated Journal Front. Astron. Space Sci.
Volume 8 Issue Pages 681084 - 10pp
Keywords primordial black holes; dark matter; cosmology; accretion; 21 cm cosmology; gravitational waves; cosmic microwave background; microlensing
Abstract Primordial black holes (PBHs) represent a natural candidate for one of the components of the dark matter (DM) in the Universe. In this review, we shall discuss the basics of their formation, abundance and signatures. Some of their characteristic signals are examined, such as the emission of particles due to Hawking evaporation and the accretion of the surrounding matter, effects which could leave an impact in the evolution of the Universe and the formation of structures. The most relevant probes capable of constraining their masses and population are discussed.
Address [Villanueva-Domingo, Pablo; Mena, Olga; Palomares-Ruiz, Sergio] CSIC Univ Valencia, Inst Fis Corpuscular IFIC, Paterna, Spain, Email: pablo.villanueva.domingo@gmail.com
Corporate Author Thesis
Publisher Frontiers Media Sa Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2296-987x ISBN Medium
Area Expedition Conference
Notes WOS:000660081700001 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 4852
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Author (up) Villanueva-Domingo, P.; Villaescusa-Navarro, F.
Title Removing Astrophysics in 21 cm Maps with Neural Networks Type Journal Article
Year 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 (up) Vincent, A.C.; Scott, P.
Title Thermal conduction by dark matter with velocity and momentum-dependent cross-sections Type Journal Article
Year 2014 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 04 Issue 4 Pages 019 - 31pp
Keywords dark matter theory; stars
Abstract We use the formalism of Gould and Raffelt [1] to compute the dimensionless thermal conduction coefficients for scattering of dark matter particles with standard model nucleons via cross-sections that depend on the relative velocity or momentum exchanged between particles. Motivated by models invoked to reconcile various recent results in direct detection, we explicitly compute the conduction coefficients alpha and kappa for cross-sections that go as v(rel)(2), v(rel)(4), v(rel)(-2), q(2), q(4) and q(-2), where v(rel) is the relative DM-nucleus velocity and q is the momentum transferred in the collision. We find that a v(rel)(-2) depend ence can significantly enhance energy transport from the inner solar core to the outer core. The same can true for any q-dependent coupling, if the dark matter mass lies within some specific range for each coupling. This effect can complement direct searches for dark matter; combining these results with state-of-the-art solar simulations should greatly increase sensitivity to certain DM models. It also seems possible that the so-called Solar Abundance Problem could be resolved by enhanced energy transport in the solar core due to such velocity-or momentum-dependent scatterings.
Address [Vincent, Aaron C.] Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, E-46071 Valencia, Spain, Email: vincent@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 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000343042800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1962
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Author (up) XENON Collaboration (Aprile, E. et al); Orrigo, S.E.A.
Title Conceptual design and simulation of a water Cherenkov muon veto for the XENON1T experiment Type Journal Article
Year 2014 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 9 Issue Pages P11006 - 20pp
Keywords Cherenkov detectors; Cherenkov and transition radiation; Detector modelling and simulations I (interaction of radiation with matter, interaction of photons with matter, interaction of hadrons with matter, etc); Dark Matter detectors (WIMPs, axions, etc.)
Abstract XENON is a dark matter direct detection project, consisting of a time projection chamber (TPC) filled with liquid xenon as detection medium. The construction of the next generation detector, XENON1T, is presently taking place at the Laboratori Nazionali del Gran Sasso (LNGS) in Italy. It aims at a sensitivity to spin-independent cross sections of 2.10(47) cm(2) for WIMP masses around 50 GeV/c(2), which requires a background reduction by two orders of magnitude compared to XENON100, the current generation detector. An active system that is able to tag muons and muon-induced backgrounds is critical for this goal. A water Cherenkov detector of similar to 10m height and diameter has been therefore developed, equipped with 8 inch photomultipliers and cladded by a reflective foil. We present the design and optimization study for this detector, which has been carried out with a series of Monte Carlo simulations. The muon veto will reach very high detection efficiencies for muons (> 99.5%) and showers of secondary particles from muon interactions in the rock (> 70%). Similar efficiencies will be obtained for XENONnT, the upgrade of XENON1T, which will later improve the WIMP sensitivity by another order of magnitude. With the Cherenkov water shield studied here, the background from muon-induced neutrons in XENON1T is negligible.
Address [Aprile, E.; Contreras, H.; Goetzke, L. W.; Fernandez, A. J. Melgarejo; Messina, M.; Plante, G.; Rizzo, A.] Columbia Univ, Dept Phys, New York, NY 10027 USA, Email: dr.serena.fattori@gmail.com
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 1748-0221 ISBN Medium
Area Expedition Conference
Notes WOS:000345026000020 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2061
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