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Author |
Capozzi, F.; Ferreira, R.Z.; Lopez-Honorez, L.; Mena, O. |
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Title |
CMB and Lyman-alpha constraints on dark matter decays to photons |
Type |
Journal Article |
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Year |
2023 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
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Volume |
06 |
Issue |
6 |
Pages |
060 - 23pp |
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Keywords |
reionization; axions; cosmological parameters from CMBR; dark matter theory |
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Abstract |
Dark matter energy injection in the early universe modifies both the ionization history and the temperature of the intergalactic medium. In this work, we improve the CMB bounds on sub-keV dark matter and extend previous bounds from Lyman-& alpha; observations to the same mass range, resulting in new and competitive constraints on axion-like particles (ALPs) decaying into two photons. The limits depend on the underlying reionization history, here accounted self-consistently by our modified version of the publicly available DarkHistory and CLASS codes. Future measurements such as the ones from the CMB-S4 experiment may play a crucial, leading role in the search for this type of light dark matter candidates. |
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Address  |
[Capozzi, Francesco] Univ Aquila, Dipartimento Sci Fis & Chim, I-67100 Laquila, Italy, Email: francesco.capozzi@univaq.it; |
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Publisher |
IOP Publishing Ltd |
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Language |
English |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1475-7516 |
ISBN |
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Expedition |
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Conference |
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Notes |
WOS:001025410500001 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
5584 |
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Author |
Capozziello, S.; Harko, T.; Koivisto, T.S.; Lobo, F.S.N.; Olmo, G.J. |
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Title |
The virial theorem and the dark matter problem in hybrid metric-Palatini gravity |
Type |
Journal Article |
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Year |
2013 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
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Volume |
07 |
Issue |
7 |
Pages |
024 - 19pp |
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Keywords |
modified gravity; dark matter theory; galaxy clusters |
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Abstract |
Hybrid metric-Palatini gravity is a recently proposed theory, consisting of the superposition of the metric Einstein-Hilbert Lagrangian with an f(R) term constructed a la Palatini. The theory predicts the existence of a long-range scalar field, which passes the Solar System observational constraints, even if the scalar field is very light, and modifies the cosmological and galactic dynamics. Thus, the theory opens new possibilities to approach, in the same theoretical framework, the problems of both dark energy and dark matter. In this work, we consider the generalized virial theorem in the scalar-tensor representation of the hybrid metric-Palatini gravity. More specifically, taking into account the relativistic collisionless Boltzmann equation, we show that the supplementary geometric terms in the gravitational field equations provide an effective contribution to the gravitational potential energy. We show that the total virial mass is proportional to the effective mass associated with the new terms generated by the effective scalar field, and the baryonic mass. In addition to this, we also consider astrophysical applications of the model and show that the model predicts that the mass associated to the scalar field and its effects extend beyond the virial radius of the clusters of galaxies. In the context of the galaxy cluster velocity dispersion profiles predicted by the hybrid metric-Palatini model, the generalized virial theorem can be an efficient tool in observationally testing the viability of this class of generalized gravity models. |
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Address |
[Capozziello, Salvatore] Univ Naples Federico II, Dipartimento Sci Fis, Naples, Italy, Email: capozzie@na.infn.it; |
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Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Edition |
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ISSN |
1475-7516 |
ISBN |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000322582000025 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
1531 |
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Author |
Caputo, A.; Regis, M.; Taoso, M.; Witte, S.J. |
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Title |
Detecting the stimulated decay of axions at radio frequencies |
Type |
Journal Article |
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Year |
2019 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
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Volume |
03 |
Issue |
3 |
Pages |
027 - 22pp |
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Keywords |
axions; dark matter theory; dark matter detectors; dwarfs galaxies |
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Abstract |
Assuming axion-like particles account for the entirety of the dark matter in the Universe, we study the possibility of detecting their decay into photons at radio frequencies. We discuss different astrophysical targets, such as dwarf spheroidal galaxies, the Galactic Center and halo, and galaxy clusters. The presence of an ambient radiation field leads to a stimulated enhancement of the decay rate; depending on the environment and the mass of the axion, the effect of stimulated emission may amplify the photon flux by serval orders of magnitude. For axion-photon couplings allowed by astrophysical and laboratory constraints (and possibly favored by stellar cooling), we find the signal to be within the reach of next-generation radio telescopes such as the Square Kilometer Array. |
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Address |
[Caputo, Andrea; Witte, Samuel J.] Univ Valencia, CSIC, Inst Fis Corpuscular, Apartado Correos 22085, E-46071 Valencia, Spain, Email: andrea0292@hotmail.it; |
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Corporate Author |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1475-7516 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000461450100002 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
3944 |
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Author |
Caputo, A.; Regis, M.; Taoso, M. |
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Title |
Searching for sterile neutrino with X-ray intensity mapping |
Type |
Journal Article |
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Year |
2020 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
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Volume |
03 |
Issue |
3 |
Pages |
001 - 21pp |
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Keywords |
X-ray telescopes; dark matter experiments; dark matter theory; power spectrum |
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Abstract |
The cosmological X-ray emission associated to the possible radiative decay of sterile neutrinos is composed by a collection of lines at different energies. For a given mass, each line corresponds to a given redshift. In this work, we cross correlate such line emission with catalogs of galaxies tracing the dark matter distribution at different redshifts. We derive observational prospects by correlating the X-ray sky that will be probed by the eROSITA and Athena missions with current and near future photometric and spectroscopic galaxy surveys. A relevant and unexplored fraction of the parameter space of sterile neutrinos can be probed by this technique. |
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Address |
[Caputo, Andrea] Univ Valencia, CSIC, Inst Fis Corpuscular, Apartado Correos 22085, E-46071 Valencia, Spain, Email: andrea.caputo@uv.es; |
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Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1475-7516 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
WOS:000528029100002 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ pastor @ |
Serial |
4385 |
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| Permanent link to this record |
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Author |
Carbone, C.; Mena, O.; Verde, L. |
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Title |
Cosmological parameters degeneracies and non-Gaussian halo bias |
Type |
Journal Article |
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Year |
2010 |
Publication |
Journal of Cosmology and Astroparticle Physics |
Abbreviated Journal |
J. Cosmol. Astropart. Phys. |
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Volume |
07 |
Issue |
7 |
Pages |
020 - 17pp |
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Keywords |
power spectrum; redshift surveys; galaxy clusters; cosmological parameters from LSS |
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Abstract |
We study the impact of the cosmological parameters uncertainties on the measurements of primordial non-Gaussianity through the large-scale non-Gaussian halo bias effect. While this is not expected to be an issue for the standard Lambda CDM model, it may not be the case for more general models that modify the large-scale shape of the power spectrum. We consider the so-called local non-Gaussianity model, parametrized by the f(NL) non-Gaussianity parameter which is zero for a Gaussian case, and make forecasts on f(NL) from planned surveys, alone and combined with a Planck CMB prior. In particular, we consider EUCLID- and LSST-like surveys and forecast the correlations among f(NL) and the running of the spectral index alpha(s), the dark energy equation of state w, the effective sound speed of dark energy perturbations c(s)(2), the total mass of massive neutrinos M-nu = Sigma m(nu), and the number of extra relativistic degrees of freedom N-nu(rel). Neglecting CMB information on f(NL) and scales k > 0.03h/Mpc, we find that, if N-nu(rel) is assumed to be known, the uncertainty on cosmological parameters increases the error on f(NL) by 10 to 30% depending on the survey. Thus the f(NL) constraint is remarkable robust to cosmological model uncertainties. On the other hand, if N-nu(rel) is simultaneously constrained from the data, the f(NL) error increases by similar to 80%. Finally, future surveys which provide a large sample of galaxies or galaxy clusters over a volume comparable to the Hubble volume can measure primordial non-Gaussianity of the local form with a marginalized 1-sigma error of the order Delta f(NL) similar to 2 – 5, after combination with CMB priors for the remaining cosmological parameters. These results are competitive with CMB bispectrum constraints achievable with an ideal CMB experiment. |
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Address |
[Carbone, Carmelita] Univ Bologna, Dipartimento Astron, I-40127 Bologna, Italy, Email: carmelita.carbone@unibo.it |
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Corporate Author |
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Thesis |
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Publisher |
Iop Publishing Ltd |
Place of Publication |
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Editor |
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Language |
English |
Summary Language |
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Original Title |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1475-7516 |
ISBN |
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Medium |
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Area |
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Expedition |
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Conference |
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Notes |
ISI:000283573200010 |
Approved |
no |
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Is ISI |
yes |
International Collaboration |
yes |
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Call Number |
IFIC @ elepoucu @ |
Serial |
347 |
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| Permanent link to this record |
