Podcasts about cresst

No dinâmico e inovador universo dos games, é imprescindível estar antenado às diversas tendências da área para avançar profissionalmente. E para conhecê-las, ninguém melhor do que um dos maiores nomes mundiais do setor Joseph Olin "King of the Games". A ACI Games e a Faculdade Impacta Tecnologia tem o orgulho de convidá-lo para acompanhar a transmissão direto do seu auditório, com tradução simultânea para o português. Joseph Olin é ex-presidente da Academy of Interactive Arts & Sciences, diretor executivo da Digital Media & Arts Association International (DMAa)e fundador da consultoria de jogos digitais It's a Secret. Olin criou eventos como o Interactive Awards e o Into the Pixel, e durante os anos de carreira na área, esteve envolvido no lançamento de centenas de títulos e produtos interativos, como o game Tomb Raider e sua protagonista Lara Croft. Passou por estúdios como Eidos e Elliot Portwood, e empresas como Ogilvy & Mather, Mattel e Philip Media. Olin também atua como conselheiro consultivo para empresas como Federação Internacional das Associações de multimídia (FIAM), SMU, China Joy, ANIM, FX Nova Zelândia, SIGGRAPH , UCLA e CRESST, além de ser palestrante em diversos eventos ao redor do mundo, como a próxima Campus Party Brasil 2014.

Scintillating CaWO4 single crystals are a promising multi-element target for rare-event searches and are currently used in the direct dark matter experiment CRESST (Cryogenic Rare Event Search with Superconducting Thermometers). The relative light output of different particle interactions in CaWO4 is quantified by quenching factors (QFs). These are essential for an active background discrimination and the identification of a possible signal induced by weakly interacting massive particles (WIMPs). We present the first precise measurements of the QFs of O, Ca and W at mK temperatures by irradiating a cryogenic detector with a fast neutron beam. A clear energy dependence of the QF of O and, less pronounced, of Ca was observed for the first time. Furthermore, in CRESST neutron-calibration data a variation of the QFs among different CaWO4 single crystals was found. For typical CRESST

Tue, 22 Sep 2009 12:00:00 +0100 https://edoc.ub.uni-muenchen.de/10946/ https://edoc.ub.uni-muenchen.de/10946/1/Bavykina_Irina.pdf Bavykina, Irina ddc:530, ddc:500, Fa

The CRESST (Cryogenic Rare Event Search with Superconducting Thermometers) Dark Matter search is aiming to directly detect Weakly Interacting Massive Particles (WIMPs) via their elastic scattering off nuclei in a target. Due to the low event rate expected for WIMP-nucleus scattering the suppression of background which would hide or mimic the WIMP signal is of crucial importance. Moreover, since the energy transferred to a nucleus in a WIMP-nucleus elastic scattering is extremely low (a few tens of keV), the energy threshold and the sensitivity of detectors are additional fundamental issues in a Dark Matter search. CRESST detectors consist of a 300g CaWO4 scintillating crystal operated as a cryogenic calorimeter in close proximity to a second much smaller cryogenic calorimeter used to detect the scintillation light produced in the target crystal. The lower light yield of nuclear recoils, caused by neutrons and WIMPs, with respect to electron recoils resulting from alpha, beta and gamma interactions is used to identify the event in the scintillating absorber. In the second phase of the CRESST experiment, active background suppression is achieved by the simultaneous measurement of a phonon and a light signal from a scintillating cryogenic calorimeter. Passive background suppression is achieved by operating CRESST detectors in a low background facility located in a deep underground site. About 1% of the energy deposited in CaWO4 by beta or gamma interactions can be detected as scintillation light; therefore the sensitivity of light detectors is a fundamental issue for the discrimination of electron recoils from nuclear recoils at energies relevant for WIMP searches. This work reports on the development of extremely sensitive cryogenic calorimeters for the detection of the scintillation light. These detectors applied a new thermometer geometry characterized by phonon collectors and a thin film thermal coupling to the heat sink. This concept allows a high sensitivity by decoupling the area required for the collection of non-thermal phonons and the heat capacity of the sensor and permits to make the thermal relaxation time of the thermometer long enough to allow for the integration of the scintillation light, despite the slow light emission of CaWO4 at low temperature. Results on new materials to be used as absorbers for a new generation of light detectors are presented. First competitive limits on WIMP Dark Matter established by the CRESST experiment running scintillating CaWO4 cryogenic detectors in association with the light detectors developed in the course of this work are reported together with main results of the detector prototyping phase.

Das CRESST Experiment im Gran Sasso Untergrundlabor sucht nach Dunkler Materie in Form von schwach wechselwirkenden massiven Teilchen (WIMPs) ueber elastische Streuung an Kernen. Die erste Phase von CRESST benutzte 262 g Saphir Kristalle als Absorber. Ein niedriger Untergrund, eine Langzeitstabilitaet des kryogenen Aufbaus, sowie eine niedrige Schwelle und eine hohe Sensitivitaet fuer leichte WIMPs wurden damit erreicht. In einer sehr stabilen Messung von 1.5 kg Tagen wurden ein Untergrund besser als 1 Ereignis/kg/Tag/keV ueber 20 keV und eine Schwelle von 580 eV erreicht. Saphir Detektoren sind besonders geeignet, um leichte WIMPs mit spin-abhaengiger Wechselwirkung zu messen. Die Ergebnisse verbessern existierende Limits in diesem Bereich. Die zweite Phase von CRESST benutzt szintillierende Kristalle als Absorber. In einem Szintillator wird nach einer Energiedeposition neben Phononen auch Licht erzeugt. Kernrueckstoesse erzeugen weniger Licht als voll ionisierende Wechselwirkungen. Die gleichzeitige Messung des Phononen- und Lichtsignals ermoeglicht eine Identifizierung der Wechselwirkung. Erste Messungen mit 300 g CaWO4 Detektoren wurden im Aufbau am Gran Sasso durchgefuehrt. Trotz einiger technischer Probleme war eine Charakterisierung der Detektoren moeglich, die das grosse Potential der Ereignisdiskriminierung aufzeigt.