Elenco seminari primo semestre 2013
9 gennaio 2013, aula 412 ore 14:00 Stanza 412, Dipartimento di Fisica
Alessio Marrani (KU Leuven)
Titolo: "Attractive Dynamics and Local Supersymmetry"
Abstract : I will present a general survey of basic facts on the attractor dynamics in extremal black hole solutions of locally supersymmetric theories of gravity.
In particular, I will consider the general issue of stability of attractor points, and the classification of U-duality charge orbits and of the corresponding "attractor moduli spaces" in four-dimensional theories based on symmetric scalar manifolds. Some brief remarks on current and future developments will be made, as well.
9 gennaio 2013, aula 412 ore 15:00 Stanza 412, Dipartimento di Fisica
Andrea Zanzi ()
Titolo: "CHAMELEONIC STRINGS AND THE COSMOLOGICAL CONSTANT PROBLEM"
Abstract: The chameleonic behaviour of the string theory dilaton and of matter fields is suggested. Some of the possible consequences of this scenario are analyzed. In particular, (1) I suggest a stringy solution to the cosmological constant problem and (2) I point out the non-equivalence of different conformal frames at the quantum level. The correct Dark Energy scale is recovered in the Einstein frame without unnatural fine-tunings and this result is robust against all quantum corrections, granted that we make some assumptions in the string-frame of the model. At this stage the possibility still exists that a certain amount of fine-tuning may be required to satisfy phenomenological constraints. A detailed phenomenological analysis of the model is definitely necessary.
Mercoledi 23 Gennaio 2013, ore 15:30 stanza 412
Massimiliano Lattanzi <lattanzi@fe.infn.it>
Title: Constraining fundamental physics with Cosmic Microwave Background observations
Abstract:
Once regarded as a data-starved science, Cosmology has become, in the last 20 years or so, a precision science. This transition has been definitely driven by the increasingly accurate measurements of the temperature anisotropies of the cosmic microwave background (CMB) radiation, from the first detection by COBE-DMR in the early 90's to the recent observations of the WMAP satellite, providing the most accurate measurement of the CMB temperature anisotropies to date, at least until the incoming release of the data from the Planck experiment.
The CMB encodes a wealth of cosmological information on the early, as well as late, Universe that can be used to constrain fundamental physics scenarios. In particular, I will concentrate on how neutrino physics can be probed through by present and future CMB experiments. The most basic information is that related to the absolute value of neutrino masses; going beyond that, I will also show some recent results concerning the amount of cosmological lepton asymmetry, as well as discuss the possibility that the dark matter is related to the origin of neutrino masses.
Prof Tsvi Piran (Schwartzmann University Chair, Gerusalemme)
terra' un ciclo di lezioni dal 28 gennaio fino a 13 febbraio 2013
su "Relativistic Transients: GRBs, Tidal Disruption Events (TDEs) and Mergers"
The lezioni (di 2 hrs ) saranno tenute il lunedi', martedi' e mercoledi' alle 15.00 (meeting room 300), per tre settimane, con inizio martedi' 29 gennaio fino a mercoledi' 13 febbraio.
Il corso, di grande attualità, è consigliato a tutti gli interessati alle tematiche di astrofisica, in particolare ai dottorandi.
Wednesday 6th February at 11:30, aula 412
Federico Urban, Universite' libre de Bruxelles
Titolo: "Cosmic Rays with Telescope Array"
Abstract: I will review the current state of art in the cosmic rays business and the latest results from the Telescope Array Project from a newcomer point of view.
Martedi' 12 febbraio 2013 alle 11.30, stanza 412
il Prof. Rocky Kolb (The University of Chicago)
Titolo: "The Decade of the WIMP"
Abstract: I will review the current situation with respect to direct detection, indirect detection, and collider production of the weakly interacting massive particle (WIMP) hypothesis for dark matter. I will go into some detail on the description of WIMP interactions with standard-model particles in terms of an effective field theory.
Lunedì 18 febbraio, Ore 16.30 stanza 412
Daniel Brandt (SLAC)
Titolo: "Scalability and the SuperCDMS Experiment"
Abstract: SuperCDMS is a dark matter direct detection experiment, searching for evidence of Weakly Interacting Massive Particles (WIMPs) scattering off conventional matter nuclei. The SuperCDMS detector is a set of high purity Germanium calorimeters, operated at cryogenic temperatures. Combined phonon and charge read out of these calorimeters yields excellent background rejection capabilities, allowing for essentially background free WIMP searches. I will discuss the SuperCDMS experiment and detection strategy, as well as the projected limits for the SuperCDMS Soudan experiment currently operational in the Soudan Underground Lab in Minnesota. I will go on to describe plans for a 2nd generation experiment, SuperCDMS SNOLAB, which aims to improve upon the limits Soudan limits by two orders of magnitude. The detector physics of the SuperCDMS experiment will be discussed in detail, along with the strategy for achieving the high target mass required to reach the SuperCDMS SNOLAB science goals.
Martedi 5 Marzo 2013, ore 11:30 stanza 412
Laura Patrizii (INFN Bologna)
Title: "Prospects in the Search for Sterile Neutrinos"
Abstract: The existence of sterile neutrinos, i.e. neutrinos not weakly interacting, gained ground in recent years as the possible explanation of unexpected results in short-baseline and reactor neutrino experiments. After briefly reviewing the present experimental framework the proposal to search for sterile neutrino in Europe at a new SBL beam at CERN will be discussed.
Ciclo di lezioni sull'argomento "Gruppi di Lie" tenuta dal Prof. Caneschi i giorni
5 marzo dalle 15 alle 17
6 marzo dalle 11 alle 12.30
7 marzo dalle 11 alle 12.30
in Aula 300, presso il Blocco C
Scopo del corso è fornire una conoscenza pragmatica dei gruppi di Lie e di passare in rivista le molte utilizzazioni dei medesimi in fisica nucleare e delle particelle. In particolare verranno considerati
a) classificazione dei gruppi di Lie e corrispondenti diagrammi di Dynkin
b) generazione delle algebre di Lie per i gruppi SU(N) , relativi tableaux di Young e come utilizzarli per decomporre il prodotto diretto di due rappresentazioni in somma di rappresentazioni irriducibili
c) le principali applicazioni dei gruppi di Lie in fisica
d) per finire verranno discussi i supergruppi della famiglia SU(N|M) con qualche applicazione dei medesimi
Il corso e' particolarmente indicato per gli studenti della laurea magistrale e per gli studenti del dottorato in fisica, ma anche ai ricercatori interessati
Venerdì 8 Marzo 2013 in aula 412 blocco C, ore 10:00
Prof. Victor. Tikhomirov Research Institute for Nuclear Problems, Minsk, Belarus
Title: "To the possibility of thorough simulation of electron and positron radiation in crystal undulators"
Abstract: "A possibility of "first principle" simulations of charged particle radiation in crystal undulators is described. The specifics of electron channeling, in that number in crystal undulators is discussed. Both MAMI experiments and a couple of experimental proposals on CU radiation of electrons are simulated as well as a possible CU experiment on Frascati positron beam. A possibility to improve crystal undulator functioning by facilitating positron capture into deep channeling states using a crystal cut or a buried oxide layer is described."
Martedi 26 Marzo, ore 15:00 stanza 200 Blocco C
Reno Mandolesi, PI Plank/LFI consortium
Title: "Rassegna dei recenti risultati sperimentali del satellite Planck"
Mercoledi' 17 Aprile ore 15:00 la stanza 412
Titolo: "Gravitational Waves as the Cause of Pulsar Glitches: Theory and Possible Instrumental Set-up for the Detection of Gravitational Waves."
Prof. Pierluigi Fortini (Dipartimento di Fisica e Scienze della Terra, Universita' di Ferrara)
Abstract - The current theory for the Gravitation Waves (GW) is that of a eld of spin 2 in a four space endowed of metric tensor gab = ab+hab and ab is the Minkowski metric tensor and hab is a function of the coordinated x; y; z; ct functioning as a eld of a GW.The equations are those linear of the general relativity. Such a simple approximation theory has not found up to now an experimental proof despite the operation of two interferometers: every attempt to demonstrate the existence of GW's have been useless. The authors of this paper have been tried other road namely the nature of a GW must be highly non linear, as Einstein said in the paper of 1916, as now we shall see. The pulsars in the Galaxy present the so called \glitch" that is the pulsars have sudden accelerations in the rotating motions followed by exponential decays which bring back the pulsar to the initial value. Such a phenomenon does not nd any satisfactory explanation: the most of the explanations leave from the inner motions of the pulsars itself coupled with the tide motions of the star itself.According the present theory these coupled
motions should produce GW's coming out from the pulsar: but this howerer was never observed.One alternave explanation is that, a GW coming from the center of the galaxy in the collision with the pulsar, yields a part of his gravitation energy causes an increasing of the rotation of the pulsar which afterwards decays at a slow pace when the GW is passed away. Let us schematize a GW as an \hump" in the at space x; y; z; ct with time extent t; t + t and which moves at a speed c i.e. the speed of light (the GW's move at the velocity of light, according the theory of general relativity). A feature of a GW is that it moves without lowering of intensity since it was produced (for example it was produced from the galactic center) up to us: as a matter of fact we are treating a GW in a way purely geometrical and threrefore such a GW is not subject to drop by a factor 1=R2 (where R is the distance from galactic center) like it happens for the electromagnetic waves. Let's assume that here on the Earth a glitch lights up and threfore, according to our assumption, it comes at the same time a GW which is detected by an interferometer; therefore (glitch + GW) at the same time.This fact would explain the reason why we have not seen up to now a GW: the GW lasts a time t; t + t and therefore the interferometer must be provided with a pulsated laser and not continuous.
Lunedi 6 Maggio, ore 10:00 stanza 412
Prof. Bondar Alex, Dean of Physics Faculty of the Novosibirsk State University, Member of the Belle Collaboration.
Titolo: "Ultimate sensitivity on \gamma/\phi_3 from B-> DK"
Abstract: Measurement of the CKM phase g in B -> DK decays can be potentially performed with high precision due to low theoretical uncertainties. However, the precision measurement requires very large experimental samples of B decays. This report covers status and prospects for precision measurement of the phase gamma at the future e+e− facilities and upgraded LHCb detector.
13 giugno alle 10:00, in aula 412
A. Adeyeye, Department of Electrical & Computer Engineering, National University of Singapore
Titolo: "Artificial Ferromagnetic Nanostructures: An Experimental Platform for Magnonics".
informazioni al sito: http://www.ieeemagnetics.org/index.php?option=com_content&view=article&id=219:adekunle-adeyeye&catid=75:2013-distinguished-lecturers-&Itemid=160
