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Author D'Eramo, F.; Di Valentino, E.; Giare, W.; Hajkarim, F.; Melchiorri, A.; Mena, O.; Renzi, F.; Yun, S. url  doi
openurl 
  Title Cosmological bound on the QCD axion mass, redux Type Journal Article
  Year 2022 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 09 Issue (down) 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  
Permanent link to this record
 

 
Author Amerio, A.; Cuoco, A.; Fornengo, N. url  doi
openurl 
  Title Extracting the gamma-ray source-count distribution below the Fermi-LAT detection limit with deep learning Type Journal Article
  Year 2023 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 09 Issue (down) 9 Pages 029 - 39pp  
  Keywords gamma ray theory; Machine learning  
  Abstract We reconstruct the extra-galactic gamma-ray source-count distribution, or dN/dS, of resolved and unresolved sources by adopting machine learning techniques. Specifically, we train a convolutional neural network on synthetic 2-dimensional sky-maps, which are built by varying parameters of underlying source-counts models and incorporate the FermiLAT instrumental response functions. The trained neural network is then applied to the Fermi-LAT data, from which we estimate the source count distribution down to flux levels a factor of 50 below the Fermi-LAT threshold. We perform our analysis using 14 years of data collected in the (1, 10) GeV energy range. The results we obtain show a source count distribution which, in the resolved regime, is in excellent agreement with the one derived from cataloged sources, and then extends as dN/dS " S-2 in the unresolved regime, down to fluxes of 5 center dot 10-12 cm-2 s-1. The neural network architecture and the devised methodology have the flexibility to enable future analyses to study the energy dependence of the source-count distribution.  
  Address [Amerio, A.] Univ Valencia, Inst Fis Corpuscular IFIC, Calle Catedrat Jose Beltran 2, Paterna 46980, Spain, Email: aurelio.amerio@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:001097055700001 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 5785  
Permanent link to this record
 

 
Author Santos, A.C.L.; Muniz, C.R.; Maluf, R.V. url  doi
openurl 
  Title Yang-Mills Casimir wormholes in D=2+1 Type Journal Article
  Year 2023 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.  
  Volume 09 Issue (down) 9 Pages 022 - 24pp  
  Keywords Wormholes; Exact solutions; black holes and black hole thermodynamics in GR and beyond; gravity  
  Abstract This work presents new three-dimensional traversable wormhole solutions sourced by the Casimir density and pressures related to the quantum vacuum fluctuations in Yang-Mills (Y-M) theory. We begin by analyzing the noninteracting Y-M Casimir wormholes, initially considering an arbitrary state parameter omega and determine a simple constant wormhole shape function. Next, we introduce a new methodology for deforming the state parameter to find well-behaved redshift functions. The wormhole can be interpreted as a legitimate Casimir wormhole with an expected average state parameter of omega = 2. Then, we investigate the wormhole curvature properties, energy conditions, and stability. Furthermore, we discover a novel family of traversable wormhole solutions sourced by the quantum vacuum fluctuations of interacting Yang-Mills fields with a more complex shape function. Deforming the effective state parameter similarly, we obtain well-behaved redshift functions and traversable wormhole solutions. Finally, we examine the energy conditions and stability of solutions in the interacting scenario and compare to the noninteracting case.  
  Address [Santos, Alana C. L.; Maluf, Roberto V.] Univ Fed Ceara UFC, Departamento Fis, Campus Pici,6030, BR-60455760 Fortaleza, Ceara, Brazil, Email: alanasantos@fisica.ufc.br;  
  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:001196198800004 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 6031  
Permanent link to this record
 

 
Author Pierre Auger Collaboration (Abreu, P. et al); Pastor, S. url  doi
openurl 
  Title Search for first harmonic modulation in the right ascension distribution of cosmic rays detected at the Pierre Auger Observatory Type Journal Article
  Year 2011 Publication Astroparticle Physics Abbreviated Journal Astropart Phys.  
  Volume 34 Issue (down) 8 Pages 627-639  
  Keywords Ultra-high energy cosmic rays; Large scale anisotropies; Pierre Auger Observatory  
  Abstract We present the results of searches for dipolar-type anisotropies in different energy ranges above 2.5 x 10(17) eV with the surface detector array of the Pierre Auger Observatory, reporting on both the phase and the amplitude measurements of the first harmonic modulation in the right-ascension distribution. Upper limits on the amplitudes are obtained, which provide the most stringent bounds at present, being below 2% at 99% C.L. for EeV energies. We also compare our results to those of previous experiments as well as with some theoretical expectations.  
  Address [Abreu, P.; Andringa, S.; Assis, P.; Brogueira, P.; Cazon, L.; Conceicao, R.; Goncalves, P.; Pimenta, M.; Santo, C. E.; Santos, E.; Tome, B.] LIP, P-1000 Lisbon, Portugal  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0927-6505 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000288930200007 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 593  
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Author ANTARES Collaboration (Ageron, M. et al); Aguilar, J.A.; Bigongiari, C.; Dornic, D.; Emanuele, U.; Gomez-Gonzalez, J.P.; Hernandez-Rey, J.J.; Mangano, S.; Ruiz-Rivas, J.; Salesa, F.; Sanchez-Losa, A.; Toscano, S.; Yepes, H.; Zornoza, J.D.; Zuñiga, J. url  doi
openurl 
  Title The ANTARES telescope neutrino alert system Type Journal Article
  Year 2012 Publication Astroparticle Physics Abbreviated Journal Astropart Phys.  
  Volume 35 Issue (down) 8 Pages 530-536  
  Keywords ANTARES; Neutrino astronomy; Transient sources; Optical follow-up  
  Abstract The ANTARES telescope has the capability to detect neutrinos produced in astrophysical transient sources. Potential sources include gamma-ray bursts, core collapse supernovae, and flaring active galactic nuclei. To enhance the sensitivity of ANTARES to such sources, a new detection method based on coincident observations of neutrinos and optical signals has been developed. A fast online muon track reconstruction is used to trigger a network of small automatic optical telescopes. Such alerts are generated for special events, such as two or more neutrinos, coincident in time and direction, or single neutrinos of very high energy.  
  Address [Ageron, M.; Al Samarai, I.; Aubert, J. -J.; Bertin, V.; Brunner, J.; Busto, J.; Carr, J.; Charif, Z.; Costantini, H.; Coyle, P.; Curtil, C.; Ernenwein, J-P.; Escoffier, S.; Galata, S.; Halladjian, G.; Hallewell, G.; Payre, P.; Picot-Clemente, N.; Riviere, C.; Vecchi, M.] Aix Marseille Univ, CPPM, CNRS, IN2P3, Marseille, France, Email: vecchi@cppm.in2p3.fr  
  Corporate Author Thesis  
  Publisher Elsevier Science Bv Place of Publication Editor  
  Language English Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0927-6505 ISBN Medium  
  Area Expedition Conference  
  Notes WOS:000301312000005 Approved no  
  Is ISI yes International Collaboration yes  
  Call Number IFIC @ pastor @ Serial 933  
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