3 research outputs found
Dimuon results in PbPb and pp collisions in CMS
The LHC offers unique opportunities for studying the properties of hot QCD
matter created in Pb+Pb collisions at extreme temperatures and very low parton
momentum fractions. With its high precision, large acceptance for tracking and
calorimetry, and a trigger scheme that allows analysis of each minimum bias
Pb+Pb event, CMS is fully equipped to measure dimuons in the high multiplicity
environment of Pb+Pb collisions. Such probes are especially relevant since they
are produced at early times and propagate through the medium, mapping its
evolution. The capabilities of the CMS experiment to study dimuon production in
pp and Pb+Pb collisions based on the 2010 LHC runs will be reviewed. CMS is
able to measure primary and secondary J/psi, as well as the three Upsilon
states. Quarkonia results at sqrt(s)=2.76 TeV in pp and Pb+Pb will be
presented, including a tantalizing observation of suppression of the Upsilon
excited states. The Z0 boson inclusive and differential measurement as a probe
of the initial state will be described.Comment: 3 pages, 4 figures. To appear in the proceedings of PANIC 201
Antecedentes del Servicio Meteorol贸gico en Espa帽a: la correspondencia entre Arcimis y Pujaz贸n
Augusto Arcimis Wehrle, nacido en Sevilla el 4 de Diciembre de 1844, fue nombrado en 1888 director de la instituci贸n que actualmente se denomina Agencia Estatal de Meteorolog铆a, creada por Real Decreto de 1887 con el nombre de Instituto Central Meteorol贸gico (ICM). Se convirti贸 as铆 en el primer meteor贸logo profesional con plena dedicaci贸n en Espa帽a. Arcimis curs贸 el bachillerato en C谩diz a donde se hab铆a trasladado su familia cuando era ni帽o. All铆 se doctor贸 en Farmacia y, gracias a la fortuna familiar viaj贸 por toda Europa y lleg贸 a dominar varias lenguas. De vuelta a C谩diz se dedic贸 a diversas actividades relacionadas con los negocios familiares, pero su inter茅s principal era ya el estudio de la Astronom铆a y la Meteorolog铆a, aficiones en las que se inici贸 durante una larga estancia en Londres y que desarroll贸 como autodidacta durante muchos a帽os. En su casa de C谩diz y luego en una finca que le dej贸 su amigo Jos茅 Macpherson en Chiclana instal贸 un observatorio astron贸mico y meteorol贸gico bastante completo
Pion interferometry in Au+Au collisions at sqrt[sNN]=200GeV
We present a systematic analysis of two-pion interferometry in Au+Au collisions at sqrt[sNN]=200GeV using the STAR detector at Relativistic Heavy Ion Collider. We extract the Hanbury-Brown and Twiss radii and study their multiplicity, transverse momentum, and azimuthal angle dependence. The Gaussianness of the correlation function is studied. Estimates of the geometrical and dynamical structure of the freeze-out source are extracted by fits with blast-wave parametrizations. The expansion of the source and its relation with the initial energy density distribution is studied