Yumiceva Research Group

Research

My group is conducting physics analysis with the data collected by the CMS experiment located at the LHC, CERN, near Geneva, Switzerland. We also have significant responsibilities in the upgrade of the barrel and end-cap calorimeters. The CMS detector and the LHC accelerator are currently upgraded to run at higher luminosities starting in 2021. This data is allowing us to test our current theories and to search for new particles or forces that can provide answers to fundamental questions of nature.

Physics Projects

In summary:

• Precision measurements of the top quark properties:
• Production cross section of top quark pairs in association with photons.
• Alternative methods to measure the top quark mass.
• Search for new physics using top quarks.

Light-emitting Top Quarks

Subatomic particles such as the top quark are copiously produced in the LHC collisions. The top quark is the most massive subatomic particle ever discovered - even heavier than the Higgs boson discovered in 2012. Top quarks could provide us with an ideal opportunity to use them as a tool to search for new physics through very precise measurements of its properties. In particular, we are studying rare processes with light-emitting top quarks.

The LHC is indeed a "top factory", producing about 150 million top-quark pairs in Run-2. This large dataset has allowed us to make precise measurements of the properties of the top quark such as mass, spin correlations, width, and forward-backward asymmetry, and to set strong bounds on new physics. The knowledge of the coupling of the top quark to $$\gamma$$, Z, and the Higgs boson are less known and mostly come from indirect measurements. The Run-2 data is enabling the possibility of making detail studies of these couplings despite the small production rate, branching fractions, and large backgrounds in these channels. We expect to have about 60,000 $$t\bar{t}\gamma$$ and 750 $$t\bar{t}Z$$ events with semileptonic decaying top quark pairs in a fiducial region from 150 fb$$^{-1}$$ of integrated luminosity.

Detector Projects

In summary:

• Design of electronic circuit boards.
• Design of FPGA boards.
• Cosmic ray detectors.

Computing Projects

• Use of GPUs for data analysis.
• Test of artificial intelligence algorithms.