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Author Lattanzi, M.; Riemer-Sorensen, S.; Tortola, M.; Valle, J.W.F.
Title Updated CMB and x- and gamma-ray constraints on Majoron dark matter Type Journal Article
Year 2013 Publication Physical Review D Abbreviated Journal Phys. Rev. D
Volume 88 Issue 6 Pages 063528 - 8pp
Keywords
Abstract The Majoron provides an attractive dark matter candidate, directly associated with the mechanism responsible for spontaneous neutrino mass generation within the standard model SU(3)(c) circle times SU(2)(L) circle times U(1)(Y) framework. Here we update the cosmological and astrophysical constraints on Majoron dark matter coming from the cosmic microwave background and a variety of x- and gamma-ray observations.
Address [Lattanzi, Massimiliano] Univ Ferrara, Dipartimento Fis & Sci Terra, I-44122 Ferrara, Italy, Email: lattanzi@fe.infn.it
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1550-7998 ISBN Medium
Area Expedition Conference
Notes WOS:000324760500004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1595
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Author Lopez-Honorez, L.; Mena, O.; Palomares-Ruiz, S.; Vincent, A.C.
Title Constraints on dark matter annihilation from CMB observations before Planck Type Journal Article
Year 2013 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 07 Issue 7 Pages 046 - 26pp
Keywords dark matter theory; CMBR theory
Abstract We compute the bounds on the dark matter (DM) annihilation cross section using the most recent Cosmic Microwave Background measurements from WMAP9, SPT'11 and ACT'10. We consider DM with mass in the MeV-TeV range annihilating 100% into either an e(+)e(-) or a mu(+)mu(-) pair. We consider a realistic energy deposition model, which includes the dependence on the redshift, DM mass and annihilation channel. We exclude the canonical thermal relic abundance cross section (<sigma nu > = 3 x 10(-26) cm(3)s(-1)) for DM masses below 30 GeV and 15 GeV for the e(+)e(-) and mu(+)mu(-) channels, respectively. A priori, DM annihilating in halos could also modify the reionization history of the Universe at late times. We implement a realistic halo model taken from results of state-of-the-art N-body simulations and consider a mixed reionization mechanism, consisting on reionization from DM as well as from first stars. We find that the constraints on DM annihilation remain unchanged, even when large uncertainties on the halo model parameters are considered.
Address [Lopez-Honorez, Laura] Vrije Univ Brussel, B-1050 Brussels, Belgium, Email: llopezho@vub.ac.be;
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:000322582000047 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1533
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Author Pierre Auger Collaboration (Abreu, P. et al); Pastor, S.
Title Techniques for measuring aerosol attenuation using the Central Laser Facility at the Pierre Auger Observatory Type Journal Article
Year 2013 Publication Journal of Instrumentation Abbreviated Journal J. Instrum.
Volume 8 Issue Pages P04009 - 28pp
Keywords Data analysis; Large detector systems for particle and astroparticle physics; Detector alignment and calibration methods (lasers, sources, particle-beams)
Abstract The Pierre Auger Observatory in Malargue, Argentina, is designed to study the properties of ultra-high energy cosmic rays with energies above 10(18) eV. It is a hybrid facility that employs a Fluorescence Detector to perform nearly calorimetric measurements of Extensive Air Shower energies. To obtain reliable calorimetric information from the FD, the atmospheric conditions at the observatory need to be continuously monitored during data acquisition. In particular, light attenuation due to aerosols is an important atmospheric correction. The aerosol concentration is highly variable, so that the aerosol attenuation needs to be evaluated hourly. We use light from the Central Laser Facility, located near the center of the observatory site, having an optical signature comparable to that of the highest energy showers detected by the FD. This paper presents two procedures developed to retrieve the aerosol attenuation of fluorescence light from CLF laser shots. Cross checks between the two methods demonstrate that results from both analyses are compatible, and that the uncertainties are well understood. The measurements of the aerosol attenuation provided by the two procedures are currently used at the Pierre Auger Observatory to reconstruct air shower data.
Address Ctr Atom Bariloche, San Carlos De Bariloche, Rio Negro, Argentina
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:000317462400016 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1413
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Author Emmanuel-Costa, D.; Simoes, C.; Tortola, M.
Title The minimal adjoint-SU (5) x Z(4) GUT model Type Journal Article
Year 2013 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages 054 - 30pp
Keywords Neutrino Physics; GUT; Discrete and Finite Symmetries
Abstract An extension of the adjoint SU (5) model with a flavour symmetry based on the Z(4) group is investigated. The Z(4) symmetry is introduced with the aim of leading the up-and down-quark mass matrices to the Nearest-Neighbour-Interaction form. As a consequence of the discrete symmetry embedded in the SU (5) gauge group, the charged lepton mass matrix also gets the same form. Within this model, light neutrinos get their masses through type-I, type-III and one-loop radiative seesaw mechanisms, implemented, respectively, via a singlet, a triplet and an octet from the adjoint fermionic 24 fields. It is demonstrated that the neutrino phenomenology forces the introduction of at least three 24 fermionic multiplets. The symmetry SU (5) x Z(4) allows only two viable zero textures for the effective neutrino mass matrix. It is showed that one texture is only compatible with normal hierarchy and the other with inverted hierarchy in the light neutrino mass spectrum. Finally, it is also demonstrated that Z(4) freezes out the possibility of proton decay through exchange of coloured Higgs triplets at tree-level.
Address [Emmanuel-Costa, D.; Simoes, C.] Univ Lisbon, Inst Super Tecn, Dept Fis, P-1049001 Lisbon, Portugal, Email: david.costa@ist.utl.pt;
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:000325495200002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1604
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Author Alioli, S.; Fernandez, P.; Fuster, J.; Irles Quiles, A.; Moch, S.; Uwer, P.; Vos, M.
Title A new observable to measure the top-quark mass at hadron colliders Type Journal Article
Year 2013 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 73 Issue 5 Pages 2438 - 11pp
Keywords
Abstract A new method to measure the top-quark mass in high energetic hadron collisions is presented. We use theoretical predictions calculated at next-to-leading order accuracy in quantum chromodynamics to study the ( normalized) differential distribution of the t (t) over bar + 1-jet cross section with respect to its invariant mass root s(t (t) over barj). The sensitivity of the method to the top-quark mass together with the impact of various theoretical and experimental uncertainties has been investigated and quantified. The new method allows for a complementary measurement of the top-quark mass parameter and has a high potential to become competitive in precision with respect to established approaches. Furthermore we emphasize that in the proposed method the mass parameter is uniquely defined through one-loop renormalization.
Address LBNL, Berkeley, CA 94720 USA, Email: Peter.Uwer@physik.hu-berlin.de
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 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000319518900023 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1468
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