First Name
Wojtek
Last Name
Fedorko
Position
Research Associate
Office Room
Hennings 209
Lab Room
Hennings 207
Tel (Office)
(604) 822-7974
Tel (Lab)
(604) 822-4869
Email
wfedorko@phas.ubc.ca
Students Wanted
actively recruiting

Bachelor's Degree
University of Toronto (2003)

Master's Degree
University of Chicago (2005)

Doctoral Degree
University of Chicago (2008)

Employment History
  • Postdoctoral Research Associate, University of British Columbia, Oct 2012 – present
  • Postdoctoral Research Associate, Michigan State University, Nov 2010 – Sept 2012
  • CERN Fellow, Oct 2008 – Oct 2010

Research Field
High Energy Physics, ATLAS, LHC

Research Topics
Searches for physics beyond the Standard Model, Dilepton resonance searches, Contact interaction searches, Z-gamma resonance searches, machine learning applications to boosted boson tagging and complex event topology analysis. Trigger electronics and logic, ATLAS Inner tracker upgrade

Research Title
Research Associate

Abstract

The Standard Model of particle physics is an amazingly powerful theory in it's predictive power. Our state of knowledge about fundamental constituents of matter and their interactions is astounding. The truly exciting fact is that the Standard Model can not be the whole story. We have powerful hints to that effect from all corners - observational and theoretical. My primary interest is to search for traces of new physics in the data collected by the ATLAS detector at the LHC. Over last several years I have been searching for high mass particles decaying to a pair of electrons or pair of muons. These sort of objects must exist if there are symmetries in nature that are bigger than that of the Standard Model. I have just published results with data at center of mass energy of 13 TeV. Unfortunately no new heavy particle was seen, however a possibility remains that it will be found in the huge dataset that is being collected this year. I am also developing techniques for boosted object tagging and analysis of rich event topologies utilising modern machine learning techniques. Such techniques could improve the reach of searches for heavy resonances decaying to top quarks, searches for dark matter and analysis of rare processes.

Before the on-going LHC Run 2 started developed firmware for and commissioned one of the trigger components for ATLAS. The trigger is a system designed to process a vast stream of data in real time and store only the interesting ones. At the LHC 40 million colissions occur every second and we can afford to permanrently store about 1000 per second. The trigger systems throws out most of the data but must not reject any interesting events. The job is accomplished partly in dedicated hardware computing components and at later stages in software running on a large CPU farm. My system works at one of the first stages of the data processing - the logic that processes calorimetric information is implemented in large Field Programmable Gate Arrays. Sheer data volume that has to be processed is staggering. The logic component I am working on processes  roughly 10 GB of data every second (and we have 12 of these modules in the system!). Latency, or the time that output is ready after receiving the input data, has to be cut to the minimum. My module produces the output in just over 100 ns.

Moving on from the 2013-2014 'Long Shutdown 1' trigger upgrade I turn my attention to future upgrades of the detector. The UBC group is contributing to the inner tracking detector upgrade to be deployed mid-next decade. I am involved in developing digital front-end readout for a CMOS technology option for the strip detector. I am also interested in application of High Level Synthesis in acceleration of complex algorithms encountered in particle physics.


Selected Publications

Search for new phenomena in the dilepton final state using proton-proton collisions at   sqrt(s) = 13 TeV with the ATLAS detector

M. Aaboud et al. [ATLAS Collaboration]

[arXiv: 1607.03669 [hep-ex]] Submitted to Phys. Lett, B

 

Search for high-mass dilepton resonances in pp collisions at sqrt(s) = 8 TeV with the ATLAS detector

G. Aad et al. [ATLAS Collaboration]

Phys. Rev. D90 052005 (2014) [arXiv: 1405.4123 [hep-ex]].

 

Search for contact interactions and large extra dimensions in the dilepton channel using

proton-proton collisions at sqrt(s)= 8 TeV with the ATLAS detector

G. Aad et al. [ATLAS Collaboration]

Accepted by EPJC [arXiv: 1407.2410 [hep-ex]].

 

Search for high-mass resonances decaying to dilepton final states in pp collisions at

sqrt(s) = 7 TeV with the ATLAS detector

G. Aad et al. [ATLAS Collaboration]

JHEP 1211, 138 (2012) [arXiv: 1209.2535 [hep-ex]].

 

Search for contact interactions and large extra dimensions in dilepton events from pp

collisions at sqrt(s) = 7 TeV with the ATLAS detector

G. Aad et al. [ATLAS Collaboration]

Phys. Rev. D87, 015010 (2013) [arXiv:1211.1150 [hep-ex]].

 

Search for dilepton resonances in pp collisions at sqrt(s)= 7 TeV with the ATLAS detector

G. Aad et al. [ATLAS Collaboration]

Phys. Rev. Lett. 107, 272002 (2011) [arXiv:1108.1582 [hep-ex]].

 

Search for contact interactions in dilepton events from pp collisions at sqrt(s)= 7 TeV with

the ATLAS detector

G. Aad et al. [ATLAS Collaboration]

Phys. Lett. B 712, 40 (2012) [arXiv:1112.4462 [hep-ex]].

 

Search for Extra Dimensions using diphoton events in 7 TeV proton-proton collisions with

the ATLAS detector

G. Aad et al. [ATLAS Collaboration]

Phys. Lett. B 710, 538–556 (2012) [arXiv:1112.2194 [hep-ex]].

 

Measurements of the electron and muon inclusive cross-sections in proton-proton collisions

at sqrt(s)= 7 TeV with the ATLAS detector

G. Aad et al. [ATLAS Collaboration]

Phys. Lett. B 707, 438-458 (2012) [arXiv:1109.0525 [hep-ex]].

 

Search for high mass dilepton resonances in pp collisions at sqrt(s) = 7 TeV with the ATLAS

experiment

G. Aad et al. [ATLAS Collaboration],

Phys. Lett. B700, 163-180 (2011). [arXiv:1103.6218 [hep-ex]].

 

First simultaneous measurement of the top quark mass in the lepton + jets and dilepton

channels at CDF

T. Aaltonen et al. [CDF Collaboration],

Phys. Rev. D79 092005 (2009). [arXiv:0809.4808 [hep-ex]].

 

CDF level 2 trigger upgrade

K. Anikeev et al.

IEEE Trans.Nucl.Sci. 53, 653-658 (2006) [DOI:10.1109/TNS.2006.871782]