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Valparaiso, Chile

The Federico Santa María Technical University is a Chilean university founded in 1926 in Valparaíso, Chile. The University has campuses in Valparaiso, Viña del Mar, Santiago, Talcahuano and Rancagua, as well as an international campus in Guayaquil, Ecuador. Santa María University is the alma mater of several prominent businessmen, engineers and Chilean scientists. Its students and Alumni are known as "Sansanos".UTFSM was the first Chilean university to confer a doctorate in engineering in 1962 and the first higher-education institution in Latin America to confer this degree. The university has special emphasis in basic science, engineering and technical fields with a more recent growth into economics and business science. Admission is very competitive and, in general, the last selected students every year have obtained around 650 points in the national admission test and therefore, correspond to the best 10% country. Santa Maria University has been historically perceived as one of the most prestigious engineering schools in the country and more recently, with the appearance of national and international rankings, has been placed among the top Universities in Chile and South America. Wikipedia.

Gustafsson M.,Free University of Colombia | No J.M.,University of Sussex | Rivera M.A.,Federico Santa Maria Technical University
Physical Review Letters | Year: 2013

A minimal extension of the standard model to naturally generate small neutrino masses and provide a dark matter candidate is proposed. The dark matter particle is part of a new scalar doublet field that plays a crucial role in radiatively generating neutrino masses. The symmetry that stabilizes the dark matter also suppresses neutrino masses to appear first at three-loop level. Without the need of right-handed neutrinos or other very heavy new fields, this offers an attractive explanation of the hierarchy between the electroweak and neutrino mass scales. The model has distinct verifiable predictions for the neutrino masses, flavor mixing angles, colliders, and dark matter signals. © 2013 American Physical Society. Source

Suarez Morell E.,Federico Santa Maria Technical University | Foa Torres L.E.F.,National University of Cordoba
Physical Review B - Condensed Matter and Materials Physics | Year: 2012

We report on the effects of laser illumination on the electronic properties of bilayer graphene. By using Floquet theory combined with Green's functions, we unveil the appearance of laser-induced gaps not only at integer multiples of Ω/2 but also at the Dirac point with features which are shown to depend strongly on the laser polarization. Trigonal warping corrections are shown to lead to important corrections for radiation in the terahertz range, reducing the size of the dynamical gaps. Furthermore, our analysis of the topological properties at low energies reveals that, when irradiated with linearly polarized light, ideal bilayer graphene behaves as a trivial insulator, whereas circular polarization leads to a nontrivial insulator per valley. © 2012 American Physical Society. Source

Kopeliovich B.Z.,Federico Santa Maria Technical University
Nuclear Physics A | Year: 2011

Nuclear effects for J/Ψ production in pA collisions are controlled by the coherence and color transparency effects. Color transparency onsets when the time of formation of the charmonium wave function becomes longer than the inter-nucleon spacing. In this energy regime the effective break-up cross section for a c̄c dipole depends on energy and nuclear path length, and agrees well with data from fixed target experiments, both in magnitude and energy dependence. At higher energies of RHIC and LHC coherence in c̄c pair production leads to charm quark shadowing which is a complement to the high twist break up cross section. These two effects explain well with no adjusted parameters the magnitude and rapidity dependence of nuclear suppression of J/Ψ observed at RHIC in dAu collisions, while the contribution of leading twist gluon shadowing is found to be vanishingly small. A novel mechanism of double color filtering for c̄c dipoles makes nuclei significantly more transparent in AA compared to pA collisions. This is one of the mechanisms which make impossible a model independent "data driven" extrapolation from pA to AA. This effect also explains the enhancement of nuclear suppression observed at forward rapidities in AA collisions at RHIC, what hardly can be related to the produced dense medium. J/Ψ is found to be a clean and sensitive tool measuring the transport coefficient characterizing the dense matter created in AA collisions. RHIC data for pT dependence of J/Ψ production in nuclear collisions are well explained with the low value of the transport coefficient q̂0<0.5 GeV2/fm. © 2010 Elsevier B.V. Source

Rezaeian A.H.,Federico Santa Maria Technical University
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2012

We investigate semi-inclusive photon-hadron production in the color-glass-condensate framework at RHIC and the LHC energies in proton-proton (pp) and proton-nucleus (pA) collisions. We calculate the coincidence probability for azimuthal correlation of pairs of photon-hadron production and show that the away-side correlations have a double-peak or a single-peak structure depending on trigger particle selection and kinematics. This novel feature is unique for semi-inclusive photon-hadron production compared to a similar measurement for double inclusive dihadron production in pA collisions. We obtain necessary conditions between kinematic variables for the appearance of a double-peak or a single-peak structure for the away-side photon-hadron correlations in pp and pA collisions at forward rapidities and show that this feature is mainly controlled by the ratio z T=pThadron/pTphoton. Decorrelation of away-side photon-hadron production by increasing the energy, rapidity and density, and appearance of double-peak structure can be understood by QCD saturation physics. We also provide predictions for the ratio of single inclusive prompt photon to hadron production, and the two-dimensional nuclear modification factor for the semi-inclusive photon-hadron pair production at RHIC and the LHC at forward rapidities. © 2012 American Physical Society. Source

Rezaeian A.H.,Federico Santa Maria Technical University
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2013

The first moment 〈pT〉 of the charged-particle transverse momentum spectrum and its correlation with the charged-particle multiplicity Nch provide vital information about the underlying particle production mechanism. The ALICE Collaboration recently reported that 〈pT〉 versus Nch in Pb+Pb collisions is smaller than in p+p and p+Pb collisions. Other interesting features of data is rather flatness of 〈pT〉 at high Nch in Pb+Pb and p+Pb collisions in seemingly striking contrast to the case of p+p collisions. With a detailed calculation, we show all these peculiar features in a wide range of energies and system sizes can be well described by the idea of gluon saturation within the Color Glass Condensate framework using the kT-factorization. This establishes an important fact that the bulk of the produced particles in heavy-ion collisions at the LHC carries signature of the initial stage of collisions. We also show that the recent scaling property seen by the CMS Collaboration between the number of tracks in p+p and p+Pb collisions may provide a strong evidence in favor of geometric-scaling phenomenon and gluon saturation, indicating that the underlying dynamics of high multiplicity events in p+p and p+Pb collisions should be similar. © 2013 Elsevier B.V. Source

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