Topic of the Week

Ricardo Vasquez Sierra

February 22nd and 23rd

Day Speaker Topic Where
Thursday, Mar 22nd at 2:30pm Ricardo Vasquez Sierra (UC Davis) 4th Generation Quark Searches in CMS WH11 NE (Sunrise)
Friday, Mar 23rd at 1:30pm Ricardo Vasquez Sierra (UC Davis) CMS Pixel Detector - Current status and upgrade WH11 NE (Sunrise)

Descriptions / About the scientists

Guest: Ricardo Vasquez Sierra (UC Davis)
Date: March 22nd and 23
Time: 2pm
Topic:4th Generation Quark Searches in CMS / CMS Pixel Detector - Current status and upgrade
Where: WH11 NE (Sunrise)

4th Generation Quark Searches in CMS

At present, the Standard Model includes three generations of fermions. It is natural to ask whether there could be a fourth one. The existence of a fourth generation of fermions could help resolve the matter anti-matter asymmetry in the universe and could induce the heavy neutrino as a candidate for dark matter. CMS has searched for fourth generation quarks and a summary of these searches is presented in this talk. The lower limits on the mass of a fourth generation quark has reached the critical mass of 550 GeV/c2 at which fermion,F"(Bs weak interaction become non-perturbative.

CMS Pixel Detector - Current status and upgrade

At the core of the CMS experiment one can find the silicon pixel detector. It aims to provide high precision space point measurements to reconstruct charged particle trajectories emerging from pp collisions. It is the closest detector to the interaction point, therefore it plays a key role in the identification of primary vertices, secondary vertices, and secondary tracks. All of which are essential elements in the search for new physics at the LHC. The present Pixel detector was designed for a maximum LHC luminosity of 1x1034 cm-2s-1. It will have to be upgraded for higher luminosities. For this presentation I will concentrate on the performance of the current detector during its working life and give a brief motivation and discussion about the main improvements for the detector,F"(Bs upgrade expected to be installed in 2016.

About the scientists

Ricardo was born in Mexico. He obtained his PhD on 2005 at Purdue University analyzing data collected by the L3 experiment mostly focusing on the electroweak processes Z->e+e- and Compton scattering in e+e- collisions. After his PhD in 2006 he became a postdoc at the University of California, Davis in the CMS experiment, where he started working in the Forward Pixel detector construction at FNAL and moved to CERN in 2008 for its installation and commissioning. His interests center on physics beyond the Standard Model using top-like signature searching for 4th generation heavy quarks and a heavy Z,F"(B. He has also been interested in using novel jet substructure techniques to find boosted particles whose decay products are fully reconstructed in a single jet.