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Popa V.,Romanian Space Science Institute
Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment | Year: 2011

The aim of the KM3NeT Project is to build a very large volume (more than 1 km3) neutrino telescope in the Mediterranean Sea. The up to date status of the project is presented, and the main physics goals are reviewed. The possibility to search for super-massive exotic particles (magnetic monopoles, nuclearites, Q-balls) is addressed in the final part of the paper. © 2010 Elsevier B.V. All rights reserved. Source


Popa L.A.,Romanian Space Science Institute
Journal of Cosmology and Astroparticle Physics | Year: 2011

We consider the possibility to observationally differentiate the Standard Model (SM) Higgs driven inflation with non-minimal coupling to gravity from other variants of SM Higgs inflation based on the scalar field theories with non-canonical kinetic term such as Galileon-like kinetic term and kinetic term with non-minimal derivative coupling to the Einstein tensor. In order to ensure consistent results, we study the SM Higgs inflation variants by using the same method, computing the full dynamics of the background and perturbations of the Higgs field during inflation at quantum level. Assuming that all the SM Higgs inflation variants are consistent theories, we use the MCMC technique to derive constraints on the inflationary parameters and the Higgs boson mass from their fit to WMAP7+SN+BAO data set. We conclude that a combination of the SM Higgs mass measurement by the LHC and accurate determination by the PLANCK satellite of the spectral index of curvature perturbations and tensor-to-scalar ratio will enable to distinguish among these models. We also show that the consistency relations of the SM Higgs inflation variants are distinct enough to differentiate among them. © 2011 IOP Publishing Ltd and SISSA. Source


Vatasescu M.,Romanian Space Science Institute
Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms | Year: 2012

We consider a specific wave packet preparation arising from the control of tunneling in the 0g-(6s,6p3 /2) double well potential of a Cs 2 cold molecule with chirped laser pulses. Such a possibility to manipulate the population dynamics in the 0g-(6s,6p3 /2) potential appears in a pump-dump scheme designed to form cold molecules by photoassociation of two cold cesium atoms. The initial population in the 0g-(6s,6p3 /2) double well is a wave packet prepared in the outer well at large interatomic distances (94 a0) by a photoassociation step with a first chirped pulse, being a superposition of several vibrational states whose energies surround the energy of a tunneling resonance. Our present work is focused on a second delayed chirped pulse, coupling the 0g-(6s,6p3 /2) surface with the a3Σu+(6s,6s) one in the zone of the double well barrier (15 a0) and creating deeply bound cold molecules in the a3Σu+(6s,6s) state. We explore the parameters choice (intensity, duration, chirp rate and sign) for this second pulse, showing that picoseconds pulses with a negative chirp can lead to trapping of population in the inner well in strongly bound vibrational states, out of the resonant tunneling able to transfer it back to the outer well. © 2011 Elsevier B.V. All rights reserved. Source


Casadio R.,University of Bologna | Casadio R.,National Institute of Nuclear Physics, Italy | Micu O.,Romanian Space Science Institute | Stojkovic D.,State University of New York at Buffalo
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2015

We investigate the Cosmic Censorship Conjecture by means of the horizon wave-function (HWF) formalism. We consider a charged massive particle whose quantum mechanical state is represented by a spherically symmetric Gaussian wave-function, and restrict our attention to the superextremal case (with charge-to-mass ratio α>1), which is the prototype of a naked singularity in the classical theory. We find that one can still obtain a normalisable HWF for α2<2, and this configuration has a non-vanishing probability of being a black hole, thus extending the classically allowed region for a charged black hole. However, the HWF is not normalisable for α2>2, and the uncertainty in the location of the horizon blows up at α2=2, signalling that such an object is no more well-defined. This perhaps implies that a quantum Cosmic Censorship might be conjectured by stating that no black holes with charge-to-mass ratio greater than a critical value (of the order of 2) can exist. © 2015 The Authors. Source


Casadio R.,University of Bologna | Casadio R.,National Institute of Nuclear Physics, Italy | Micu O.,Romanian Space Science Institute | Scardigli F.,Polytechnic of Milan | Scardigli F.,Kyoto University
Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics | Year: 2014

We address the issue of (quantum) black hole formation by particle collision in quantum physics. We start by constructing the horizon wave-function for quantum mechanical states representing two highly boosted non-interacting particles that collide in flat one-dimensional space. From this wave-function, we then derive a probability that the system becomes a black hole as a function of the initial momenta and spatial separation between the particles. This probability allows us to extend the hoop conjecture to quantum mechanics and estimate corrections to its classical counterpart. © 2014 The Authors. Source

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