Contact
Name
Jože Zobec

Position
PhD student
Funding: UCL-FSR
Member since November 2014

Email
jozze.zepl@gmail.com

Address
Centre for Cosmology, Particle Physics and Phenomenology - CP3
Université catholique de Louvain
2, Chemin du Cyclotron - Box L7.01.05
B-1348 Louvain-la-Neuve
Belgium

Phone
+32 10 473271
Projects
Research directions:
Data analysis in HEP experiments
Detector commissioning, operation and data processing

Experiments and collaborations:
CMS

Active projects
CMS Tracker commissioning and performance assessment
Pieter David, Christophe Delaere, Martin Delcourt, Jessica Prisciandaro, Alessia Saggio, Jože Zobec

The CMS silicon strip tracker is the largest device of its type ever built. There are 24244 single-sided micro-strip sensors covering an active area of 198m2.
Physics performance of the detector are being constantly assessed and optimized as new data comes.
Members of UCL are playing a major role in the understanding of the silicon strip tracker and in the maintenance and development of the local reconstruction code.

External collaborators: CMS tracker collaboration.
Particle Identification with ionization energy loss in the CMS experiment at the LHC
Giacomo Bruno, Claudio Caputo, Jessica Prisciandaro, Angela Taliercio, Jože Zobec

The CMS detector at the LHC can be used to identify particles via the measurement of their ionization energy loss. The sub-detectors that have provided so far useful information for this experimental technique are the silicon strip tracker and the pixel detectors. Identification of low momentum hadrons and detection of new exotic massive long-lived charged particles have all benefited from this experimental method. Members of UCL pioneered this technique in the early LHC times and have been developing the tools for its use and calibration. Since 2010 particle identification with ionization energy loss has been the basis of the CMS inclusive search for new massive long-lived charged particles, which has been providing the most stringent and model-independent limits existing to date on any model of new physics predicting such particles.

External collaborators: CMS collaboration.
Search for massive long-lived charged particles with the CMS detector at the LHC
Giacomo Bruno, Claudio Caputo, Jessica Prisciandaro, Angela Taliercio, Jože Zobec

The CMS detector at the LHC is used to search for yet unobserved heavy (mass >100 GeV/c$^2$), long-lived (lifetime > 1 ns), electrically charged particles, called generically HSCPs.
HSCPs can be distinguished from Standard Model particles by exploiting their unique signature: very high momentum and low velocity. These features are a consequence of their high mass and the relatively limited LHC collision energy. Two experimental techniques are used to identify such hypothetical heavy and low-velocity particles: the measurement of the ionization energy loss rate using the all-silicon tracker detector and the time-of-flight measurement with the muon detectors.

UCL members have developed the ionization energy loss identification technique and have lead the CMS HSCP search since 2010, when the first HSCP paper became one of the first published LHC search papers. Updated results, using the 2011 dataset, were then published followed by a comprehensive paper including also searches for fractional and multiply-charged particles published using the full CMS Run-1 dataset. The results obtained by analysing the 2015 Run 2 data at 13 TeV have also been published.

The analysis, which is very inclusive, doesn't find evidence of HSCP. It currently excludes, among various models, the existence of quasi-stable gluinos, predicted by certain realizations of supersymmetry, and Drell-Yan-produced staus with masses lower than about 1.3 TeV and 350 GeV, respectively. These and the other limits set by the analysis are the most stringent to date. The CMS HSCP papers total to date more than 300 citations.
Publications in CP3
All my publications on Inspire

Number of publications as CP3 member: 3 Download BibTeX

2017

CP3-17-56: The Phase-2 Upgrade of the CMS Tracker
CMS collaboration

[Full text]
CERN-LHCC-2017-009 ; CMS-TDR-014
Refereed paper. December 13.

2016

CP3-16-48: Search for long-lived charged particles in proton-proton collisions at sqrt(s) = 13 TeV
Khachatryan, Vardan and others

[Abstract] [PDF] [Journal] [Dial]
Submitted to Phys. Rev. D
October 6.
CP3-16-14: Searches for Long-lived Charged Particles in Proton-Proton Collisions at √s = 13 TeV
CMS Collaboration

[Full text]
CMS Physics Analysis Summary CMS-PAS-EXO-15-010
Public experimental note. April 22.