Personal Info
Contact
Georgios Konstantinos Krintiras
1251 Wescoe Hall Dr, Lawrence, KS 66045
Malott Hall, 4077 (Kansas U.)
42-3/038 (CERN)
gkrintir@SPAMNOTcern.ch
gkrintir@SPAMNOTku.edu
+41 22 76 65033 (CERN)
1251 Wescoe Hall Dr, Lawrence, KS 66045
Malott Hall, 4077 (Kansas U.)
42-3/038 (CERN)
gkrintir@SPAMNOTcern.ch
gkrintir@SPAMNOTku.edu
+41 22 76 65033 (CERN)
Positions
| Period | Rank | Institution |
|---|---|---|
| 2014 — | Researcher | CERN (CH) |
| 2020 — 2020 | LPC Guest | Fermilab (US) |
| 2019 — | PostDoc | Kansas U. (US) |
| 2015 — 2019 | PhD | Louvain U. (BE), CP3 (BE) |
| 2014 — 2015 | MSc | CERN (CH) |
| 2013 — 2015 | MSc | Amsterdam U. (NL), NIKHEF (NL) |
| 2012 — 2012 | UG | Lund U. (SE) |
| 2008 — 2012 | UG | Aristotle U. (GR) |
Personal homepage
Oral Presentations
All my conference proceedings on Inspire
Last 5 presentations
First measurement of the τ lepton photoproduction in PbPb collisions with the CMS experiment
Quark-Gluon Plasma properties
Light-by-light scattering cross-section measurements at LHC
EF07 Summary
Collectiviy in heavy ion interactions at CMS
More oral presentations
Last 5 presentations
2022
First measurement of the τ lepton photoproduction in PbPb collisions with the CMS experiment
XXIX International Workshop on Deep-Inelastic Scattering and Related Subjects, Santiago de Compostela, 05/2022
XXIX International Workshop on Deep-Inelastic Scattering and Related Subjects, Santiago de Compostela, 05/2022 (Workshop Photo)
XXIX International Workshop on Deep-Inelastic Scattering and Related Subjects, Santiago de Compostela, 05/2022 (Workshop Photo)
Quark-Gluon Plasma properties
Light-by-light scattering cross-section measurements at LHC
EF07 Summary
2021
Collectiviy in heavy ion interactions at CMS
More oral presentations
Poster Presentations
Observation of top quark production in proton-nucleus collisions
Observation of top quark production in proton-nucleus collisions
Luminosity calibration at √s = 5.02 TeV
Luminosity calibration at √s = 5.02 TeV
Measurement of the top quark pair production cross section using dilepton events at √s = 5.02 TeV
Constraining QCD multijet background in the t-channel single top-quark production at √s = 13 TeV
Observation of top quark production in proton-nucleus collisions
Luminosity calibration at √s = 5.02 TeV
Luminosity calibration at √s = 5.02 TeV
Measurement of the top quark pair production cross section using dilepton events at √s = 5.02 TeV
Constraining QCD multijet background in the t-channel single top-quark production at √s = 13 TeV
Seminar Presentations
Heavy ion physics
Top Quarks and the Little Bang Standard Model
Top Quarks and the Little Bang Standard Model
Top quark in nuclear collisions at LHC
Top quark production in nuclear collisions
Measurement of the top quark pair production cross section and luminosity calibration at √s = 5.02 TeV
Top Quarks and the Little Bang Standard Model
Top Quarks and the Little Bang Standard Model
Top quark in nuclear collisions at LHC
Top quark production in nuclear collisions
Measurement of the top quark pair production cross section and luminosity calibration at √s = 5.02 TeV
Projects
Research directions:
Experiments and collaborations:
Active projects
This project aims at the first LHC combination of light-by-light scattering cross-section measurements, using lead-lead data recorded by the ATLAS and CMS Collaborations.
The combined result will be more precise than the best individual determinations, which currently have uncertainties of 18 and 46\%, respectively, and are consistent with the standard model prediction within approximately two standard deviations.
The measured diphoton invariant mass distributions will be used to set updated exclusion limits on the production of pseudoscalar axion-like particles.
Collaborators: É. Chapon, R. Chudasama, I. Grabowska-Bold, R. Granier de Cassagnac, M. Klusek-Gawenda, M. Nguyen
The identification ("tagging") of jets from heavy-flavor hadrons can be improved by using the advances in the field of deep machine learning.
For the first time in heavy ion collisions, detailed simulation studies show that new algorithms, developed in the realm of pp collisions at CMS, outperform the existing tagging algorithms even after their reoptimization.
A new version of the default tagger ("CSVv2"), the so-called "DeepCSV", developed using a deep neural network with more hidden layers and nodes per layer, is trained for pp and PbPb collisions at 5.02 TeV.
Collaborators: L. Alcerro, B. Diab, M. Nguyen
The large mass of τ leptons compared to electrons or muons render the exceptionally clean photon fusion process, readily accessible in ultraperipheral heavy ion collisions at the LHC, an excellent hunting ground for beyond-the-standard model physics.
In the 2018 PbPb data set, CMS recorded a large sample of about events with masses between 7 and 20 GeV. This implies that there exists a smaller but comparable sample of events in the same mass range.
The analysis hinges on low- tracking combined with optimized electron and photon reconstruction. Overall, a very competitive measurement of g-2 for the τ lepton is expected with the 2018 data set, when compared to the current most precise single-experiment measurement from LEP. This analysis can benefit greatly from the prior CMS experience in measuring the light-by-light scattering process, the tracking detector expertise available at the LPC as well as easy access to computing facilities at FNAL.
Collaborators: P. Behera, R. Chudasama, A. Jofrehei, B. Kilminster, S. Leontsinis, A. Muhammad, M. Murray, M. Nickel, Y. Takahashi
The latest reference pp data set in Run 2 (2017) offers the unprecedented opportunity to improve and extend top quark pair cross section measurements at 5.02 TeV, establishing the most precise baseline evaluation with respect to heavy ions ever. The significantly larger amount of data collected by the CMS experiment (more than 10 times relative to the previous run) and the inclusion of the phase-I pixel tracker are expected to open the door to a substantially more precise measurement of the top pair inclusive production cross section, as well as differential cross sections such as the top quark transverse momentum or the kinematic properties of the hadronically decaying W boson.
We already demonstrated improved reference simulation, knowledge of the absolute luminosity scale, and b jet identification efficiency, all foreseen to contribute to a more precise measurement. On top of the ongoing analysis effort, a summer student at CERN will be recruited to further advance the measurement including the semileptonic top quark decay channels, while exploring the possibility to perform the first-ever differential cross section measurement of top quark pair kinematics at this energy regime.
Collaborators: B. Alvarez, S. Folgueras, A. Giammanco, J. González, E. Palencia, P. Silva, A. Trapote
The top quark, being the heaviest known elementary particle, is a powerful tool to test QCD. The study of top quark pair production in heavy ion collisions at LHC, making use of the dedicated pPb and PbPb runs, paves the way for the detailed investigation of the quark-gluon plasma in phase-space regions not accessible so far.
This research project started with the first measurement of top pair cross section in pp collisions at 5.02 TeV, taking advantage of a "reference run" in November 2015. This measurement, in addition to being useful as a reference for measurements in nuclear collisions at the same center-of-mass energy per nucleon, also provides a significant broadening of the lever arm for global PDF fits making use of top quark data.
More recently, we reported the observation of top quark production in pPb collisions, using the data at 8.16 TeV taken in November 2016, testing the models of nuclear modification of the gluon PDF at high Bjorken-x region.
We also published the first evidence of top pair production using PbPb collisions. We also demonstrated the feasibility of differential analyses in pPb collisions (to constrain nuclear PDFs), and we are interested in searching of central exclusive and ultraperipheral top pair production in pp and PbPb events, respectively.
Collaborators: É. Chapon, Dünser, D. d'Énterria, E. Eren, A. Giammanco, J. González, E. Lipka, M. Mulders, I. Kucher, M. Nguyen, E. Palencia, P. Silva, M. Verweij (former CMS) et al (for the central exclusive and ultraperipheral top pair analysis efforts)
We study hadronically decaying W bosons that can provide key novel insights into the time structure of the quark-gluon plasma (QGP) when studied in events with a top-antitop quark pair. This is because of a "time delay" between the moment of the collision and that when the W boson decay products start interacting with the QGP.
We perform more detailed Monte Carlo studies, e.g., taking advantage of improved jet quenching modeling and realistic physics-object reconstruction efficiencies. Although there seems to exist limited potential to bring the first information on the time structure of the QGP considering the baseline LHC scenario of Runs 3 and 4, lighter ions and/or isoscalar nuclei are potentially promising candidates despite their smaller quenching effects. Because of the potential for order-of-magnitudes higher effective integrated nucleon-nucleon luminosities, we're answering whether there is an optimal nucleus-nucleus colliding system at HL-LHC.
Collaborators: L. Alcerro, C. Royon
Precision luminosity calibration is critical to determine fundamental parameters of the standard model and to constrain or to discover beyond-the-standard-model phenomena at LHC. We convene (2019-2021 mandate) the analysis efforts related to the calibration of the luminometry system of the CMS detector, analyzing the dedicated "van der Meer scan" data at different center-of-mass energies and collision systems (pp, pPb, PbPb). The target uncertainty in the Run 2 integrated luminosity is close to the "precision frontier" of 1%, among the most precise luminosity measurements at bunched-beam hadron colliders.
As related tasks, we are also in charge of the various technical responsibilities of the lumimosity group and contribute to the data-based inference of the true amount of "pileup" collisions, which is also used as input to all Monte Carlo simulation samples in CMS.
The renewed interest for the muon collider, in particular in the multi-TeV energy range is posing several unprecedented challenges to the HEP community. We study an alternative way to determine such a fundamental parameter, based on muon Bhabha cross section production.
Collaborators: C. Schwick, P. Lujan, G.Pásztor et al (i.e., CMS Luminosity Physics Object and Beam Radiation, Instrumentation, and Luminosity Groups, Muon Collider Collaboration)
Past projects
Data analysis in HEP experiments [hep-ex, nucl-ex, hep-ph, nucl-th]
Detector commissioning, operation and data processing [physics.ins-det]
Detector commissioning, operation and data processing [physics.ins-det]
Experiments and collaborations:
Active projects
Search for axion-like particles with the ATLAS and CMS experiments
[link]
This project aims at the first LHC combination of light-by-light scattering cross-section measurements, using lead-lead data recorded by the ATLAS and CMS Collaborations.
The combined result will be more precise than the best individual determinations, which currently have uncertainties of 18 and 46\%, respectively, and are consistent with the standard model prediction within approximately two standard deviations.
The measured diphoton invariant mass distributions will be used to set updated exclusion limits on the production of pseudoscalar axion-like particles.
Collaborators: É. Chapon, R. Chudasama, I. Grabowska-Bold, R. Granier de Cassagnac, M. Klusek-Gawenda, M. Nguyen
Deep machine learning in the identification of heavy-flavor jets
[link]
The identification ("tagging") of jets from heavy-flavor hadrons can be improved by using the advances in the field of deep machine learning.
For the first time in heavy ion collisions, detailed simulation studies show that new algorithms, developed in the realm of pp collisions at CMS, outperform the existing tagging algorithms even after their reoptimization.
A new version of the default tagger ("CSVv2"), the so-called "DeepCSV", developed using a deep neural network with more hidden layers and nodes per layer, is trained for pp and PbPb collisions at 5.02 TeV.
Collaborators: L. Alcerro, B. Diab, M. Nguyen
Measuring τ lepton g-2 using LHC heavy ion collisions
[link]
The large mass of τ leptons compared to electrons or muons render the exceptionally clean photon fusion process, readily accessible in ultraperipheral heavy ion collisions at the LHC, an excellent hunting ground for beyond-the-standard model physics.
In the 2018 PbPb data set, CMS recorded a large sample of about events with masses between 7 and 20 GeV. This implies that there exists a smaller but comparable sample of events in the same mass range.
The analysis hinges on low- tracking combined with optimized electron and photon reconstruction. Overall, a very competitive measurement of g-2 for the τ lepton is expected with the 2018 data set, when compared to the current most precise single-experiment measurement from LEP. This analysis can benefit greatly from the prior CMS experience in measuring the light-by-light scattering process, the tracking detector expertise available at the LPC as well as easy access to computing facilities at FNAL.
Collaborators: P. Behera, R. Chudasama, A. Jofrehei, B. Kilminster, S. Leontsinis, A. Muhammad, M. Murray, M. Nickel, Y. Takahashi
Establishing a precise top quark reference for heavy ion collisions
[link]
The latest reference pp data set in Run 2 (2017) offers the unprecedented opportunity to improve and extend top quark pair cross section measurements at 5.02 TeV, establishing the most precise baseline evaluation with respect to heavy ions ever. The significantly larger amount of data collected by the CMS experiment (more than 10 times relative to the previous run) and the inclusion of the phase-I pixel tracker are expected to open the door to a substantially more precise measurement of the top pair inclusive production cross section, as well as differential cross sections such as the top quark transverse momentum or the kinematic properties of the hadronically decaying W boson.
We already demonstrated improved reference simulation, knowledge of the absolute luminosity scale, and b jet identification efficiency, all foreseen to contribute to a more precise measurement. On top of the ongoing analysis effort, a summer student at CERN will be recruited to further advance the measurement including the semileptonic top quark decay channels, while exploring the possibility to perform the first-ever differential cross section measurement of top quark pair kinematics at this energy regime.
Collaborators: B. Alvarez, S. Folgueras, A. Giammanco, J. González, E. Palencia, P. Silva, A. Trapote
Top quarks in heavy ion collisions and other nonstandard LHC data sets
[link]
The top quark, being the heaviest known elementary particle, is a powerful tool to test QCD. The study of top quark pair production in heavy ion collisions at LHC, making use of the dedicated pPb and PbPb runs, paves the way for the detailed investigation of the quark-gluon plasma in phase-space regions not accessible so far.
This research project started with the first measurement of top pair cross section in pp collisions at 5.02 TeV, taking advantage of a "reference run" in November 2015. This measurement, in addition to being useful as a reference for measurements in nuclear collisions at the same center-of-mass energy per nucleon, also provides a significant broadening of the lever arm for global PDF fits making use of top quark data.
More recently, we reported the observation of top quark production in pPb collisions, using the data at 8.16 TeV taken in November 2016, testing the models of nuclear modification of the gluon PDF at high Bjorken-x region.
We also published the first evidence of top pair production using PbPb collisions. We also demonstrated the feasibility of differential analyses in pPb collisions (to constrain nuclear PDFs), and we are interested in searching of central exclusive and ultraperipheral top pair production in pp and PbPb events, respectively.
Collaborators: É. Chapon, Dünser, D. d'Énterria, E. Eren, A. Giammanco, J. González, E. Lipka, M. Mulders, I. Kucher, M. Nguyen, E. Palencia, P. Silva, M. Verweij (former CMS) et al (for the central exclusive and ultraperipheral top pair analysis efforts)
Resolving the time dimension in jet quenching studies of the QGP at LHC and HL-LHC
[link]
We study hadronically decaying W bosons that can provide key novel insights into the time structure of the quark-gluon plasma (QGP) when studied in events with a top-antitop quark pair. This is because of a "time delay" between the moment of the collision and that when the W boson decay products start interacting with the QGP.
We perform more detailed Monte Carlo studies, e.g., taking advantage of improved jet quenching modeling and realistic physics-object reconstruction efficiencies. Although there seems to exist limited potential to bring the first information on the time structure of the QGP considering the baseline LHC scenario of Runs 3 and 4, lighter ions and/or isoscalar nuclei are potentially promising candidates despite their smaller quenching effects. Because of the potential for order-of-magnitudes higher effective integrated nucleon-nucleon luminosities, we're answering whether there is an optimal nucleus-nucleus colliding system at HL-LHC.
Collaborators: L. Alcerro, C. Royon
Precision luminosity calibration is critical to determine fundamental parameters of the standard model and to constrain or to discover beyond-the-standard-model phenomena at LHC. We convene (2019-2021 mandate) the analysis efforts related to the calibration of the luminometry system of the CMS detector, analyzing the dedicated "van der Meer scan" data at different center-of-mass energies and collision systems (pp, pPb, PbPb). The target uncertainty in the Run 2 integrated luminosity is close to the "precision frontier" of 1%, among the most precise luminosity measurements at bunched-beam hadron colliders.
As related tasks, we are also in charge of the various technical responsibilities of the lumimosity group and contribute to the data-based inference of the true amount of "pileup" collisions, which is also used as input to all Monte Carlo simulation samples in CMS.
The renewed interest for the muon collider, in particular in the multi-TeV energy range is posing several unprecedented challenges to the HEP community. We study an alternative way to determine such a fundamental parameter, based on muon Bhabha cross section production.
Collaborators: C. Schwick, P. Lujan, G.Pásztor et al (i.e., CMS Luminosity Physics Object and Beam Radiation, Instrumentation, and Luminosity Groups, Muon Collider Collaboration)
Publications
All my publications on Inspire
Detailed explanation of my contributions on the Publication Index
Download BibTeX
Last 10 publications
More publications
Detailed explanation of my contributions on the Publication Index
Download BibTeX
Last 10 publications
2022
CMS luminosity measurement using nucleus-nucleus collisions at 5.02 TeV in 2018
CMS Collaboration
[Full text]
Physics Analysis Note CMS-LUM-18-001, Presented at the 10th Edition of the Large Hadron Collider Physics Conference, LHCP22, Taipei, Taiwan, 16-20 May, 2022
Public experimental note. May.
[Full text]
Physics Analysis Note CMS-LUM-18-001, Presented at the 10th Edition of the Large Hadron Collider Physics Conference, LHCP22, Taipei, Taiwan, 16-20 May, 2022
Public experimental note. May.
Measurement of the inclusive top quark pair production cross section in proton-proton collisions at 5.02 TeV
Snowmass White Paper Contribution: Physics with the Phase-2 ATLAS and CMS Detectors
CMS Collaboration
[Full text]
Physics Analysis Note CMS-FTR-22-001, Contribution to 2022 Snowmass Summer Study Public experimental note. Apr 19.
[Full text]
Physics Analysis Note CMS-FTR-22-001, Contribution to 2022 Snowmass Summer Study Public experimental note. Apr 19.
Snowmass 2021 whitepaper: Proton structure at the precision frontier
Observation of τ lepton pair production in ultraperipheral nucleus-nucleus collisions
CMS Collaboration
[Full text]
Physics Analysis Note CMS-HIN-21-009, Presented at the 56th Rencontres de Moriond session devoted to Electroweak Interactions and Unified Theories, Moriond EW 2022, La Thuile, Italy, 12-19 March, 2022
Public experimental note. Mar 19.
[Full text]
Physics Analysis Note CMS-HIN-21-009, Presented at the 56th Rencontres de Moriond session devoted to Electroweak Interactions and Unified Theories, Moriond EW 2022, La Thuile, Italy, 12-19 March, 2022
Public experimental note. Mar 19.
Simulated Detector Performance at the Muon Collider
White Paper on Forward Physics, BFKL, Saturation Physics and Diffraction
2021
Luminosity measurement in proton-proton collisions at 5.02 TeV in 2017 at CMS
CMS Collaboration
[Full text]
Physics Analysis Note CMS-LUM-19-001, Presented at the 9th Edition of the Large Hadron Collider Physics Conference, LHCP21, Paris, France, 7-12 June, 2021
Public experimental note. Apr 30.
[Full text]
Physics Analysis Note CMS-LUM-19-001, Presented at the 9th Edition of the Large Hadron Collider Physics Conference, LHCP21, Paris, France, 7-12 June, 2021
Public experimental note. Apr 30.
Precision luminosity measurement in proton-proton collisions at 13 TeV in 2015 and 2016 at CMS
More publications
Further Material
Docteur en Sciences (PhD)
MSc in Particle and AstroParticle Physics
CERN Summer Student Programme 2014
Bachelor (Ptychion) in Nuclear and Particle Physics
First measurements of the top quark pair cross section in LHC pp and pPb collisions at 5.02 and 8.16 TeV and determination of the absolute luminosity in the CMS experiment, Louvain, 2019 (Thesis)
First measurements of the top quark pair cross section in LHC pp and pPb collisions at 5.02 and 8.16 TeV and determination of the absolute luminosity in the CMS experiment, Louvain, 2019 (Presentation)
First measurements of the top quark pair cross section in LHC pp and pPb collisions at 5.02 and 8.16 TeV and determination of the absolute luminosity in the CMS experiment, Louvain, 2019 (Presentation)
MSc in Particle and AstroParticle Physics
Higher-Order Azimuthal Anisotropy of 
+ 
hyperons in PbPb collisions at √s = 2.76 TeV measured with the ALICE Detector at LHC, Amsterdam, 2015 (Thesis)
Higher Harmonics in azimuthal Anisotropy of identified particles, Amsterdam, 2015 (Presentation)
+ hyperons in PbPb collisions at √s = 2.76 TeV measured with the ALICE Detector at LHC, Amsterdam, 2015 (Thesis) Higher Harmonics in azimuthal Anisotropy of identified particles, Amsterdam, 2015 (Presentation)
CERN Summer Student Programme 2014
Testing the Boosted Decision Trees (BDT) performance for + identification in PbPb collisions within the Heavy Ion Jet INteraction Generator (HIJING) model, Geneva, 2014 (Theses)
Testing the Boosted Decision Trees (BDT) performance for + identification in PbPb collisions within the Heavy Ion Jet INteraction Generator (HIJING) model, Geneva, 2014 (Presentation)
+ identification in PbPb collisions within the Heavy Ion Jet INteraction Generator (HIJING) model, Geneva, 2014 (Theses) Testing the Boosted Decision Trees (BDT) performance for
+ identification in PbPb collisions within the Heavy Ion Jet INteraction Generator (HIJING) model, Geneva, 2014 (Presentation)
Bachelor (Ptychion) in Nuclear and Particle Physics
, Miscellaneous
Responsible for central CMS data acquisition and leader of the shift crew
CMS official guide (contact me ;D)
Présentations pour la Voyage au CERN 2017
CMS Create #2
CMS official guide (contact me ;D)
Présentations pour la Voyage au CERN 2017
CMS Create #2