SCOAP3 Repository
https://repo.scoap3.org
SCOAP3 Repository latest documentsenMon, 22 Jul 2019 21:13:04 GMTInvenio 1.1.4.1330-44020repo.admin@scoap3.org3602125https://repo.scoap3.org/img/site_logo_rss.pngSCOAP3 Repository
https://repo.scoap3.org
Search Search this site:p
https://repo.scoap3.org/search
Thermal behavior and entanglement in Pb-Pb and <math><mrow><mi>p</mi><mtext>−</mtext><mi>p</mi></mrow></math> collisions
https://repo.scoap3.org/record/30530
The thermalization of the particles produced in collisions of small objects can be achieved by quantum entanglement of the partons of the initial state as was analyzed recently in proton-proton collisions. We extend such study to Pb-Pb collisions and to different multiplicities of proton-proton collisions. We observe that, in all cases, the effective temperature is approximately proportional to the hard scale of the collision. We show that such a relation between the thermalization temperature and the hard scale can be explained as a consequence of the clustering of the color sources. The fluctuations of the number of parton states decrease with multiplicity in Pb-Pb collisions as long as the width of the transverse-momentum distribution decreases, contrary to the p−p case. We relate these fluctuations to the temperature fluctuations by means of a Langevin equation for the white stochastic noise. We show that the multiplicity parton distribution for events with at least one hard parton collision is a Γ distribution. We use this result to compute the entanglement entropy, showing that the leading term is the logarithm of the number of partons, meaning that the n microstates are equally probable and the entropy is maximal. There is another contribution related to the inverse of the normalized parton number fluctuation, which at very high energy changes the behavior from lnn to lnn.Feal, X.Thu, 24 Jan 2019 17:17:06 GMThttps://repo.scoap3.org/record/30530urn:ISSN:2469-9993APS2019-01-24Transverse spectrum of bremsstrahlung in finite condensed media
https://repo.scoap3.org/record/30121
A formalism is presented in which the radiation of photons off high energy electrons during a multiple scattering process with finite condensed media can be evaluated for a general interaction. We show that the arising Landau-Pomeranchuk-Migdal suppression for finite size targets saturates at some characteristic photon energy. Medium coherence effects in the photon dispersion relation can be also considered leading to a dielectric suppression or transition radiation effects in the soft part of the spectrum. The main results of our formulation are presented for a Debye screened interaction and its well-known Fokker-Planck approximation, showing that for finite size targets or for the angular distributions of the final particles the differences between both scenarios cannot be reconciled into a single redefinition of the medium transport parameter (q^). Our predictions are in very good agreement with the experimental data collected at SLAC.Feal, X.Thu, 03 Jan 2019 01:16:08 GMThttps://repo.scoap3.org/record/30121urn:ISSN:2470-0029APS2019-01-02