Krzysztof Piotrzkowski

Academic staff


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

+32 10 47 3244


UCL member card
LPHYS2221 Astrophysics and astroparticles
LPHYS2101 Analog and digital electronics
LPHYS2102 Detectors and sensors
LPHYS2336 Advanced experimental aspects of fundamental interactions
LPHY2360 Physique atomique, nucléaire et des radiations
People responsibilities
Former members
Research statement
Studying gravitational wave signals detected by Virgo and LIGO. Participating in the development of the next generation detectors of gravitational waves. Investigating physics with the proposed detectors - the Einstein Telescope and LISA.

Studying high-energy photon interactions at hadron colliders. In particular, interested by exclusive two-photon production of pairs of heavy charged particles at the LHC. Working on novel tests of the gauge boson sector of the Standard Model and searches of physics beyond the SM. Studying the so-called ultra-peripheral collisions (UPC) involving high energy ion beams.

Working on photo-production tagging techniques, using very forward, near beam detectors at colliders. In particular, developing novel, ultra-fast Cerenkov detectors with picosecond resolution. Investigating possibility of new techques in ToF-PET. Has deep expertise in precise luminosity measurements at hadron colliders using QED processes.
Research directions:
Cosmology and General Relativity
Phenomenology of elementary particles
Data analysis in HEP and GW experiments
Detector commissioning, operation and data processing
Research and development of new detectors

Experiments and collaborations:

Active projects
E-TEST - Cryogenic inertial sensor development
Giacomo Bruno, Krzysztof Piotrzkowski, Joris van Heijningen

On Feb 1, 2020 the R&D EU Interreg project E-TEST officially started. It involves 11 institutes from Belgium, Germany and Netherlands and will carry on crucial detector developments for the Einstein Telescope (ET) - a 3rd generation antenna of gravitational waves, related mostly to cryogenic operations of large mass mirrors and their suspensions, ultra-precise metrology and sensing, as well as to advanced geological studies in the region (the ET is a deep-underground detector). The CP3 group is a partner in this project and is working on work package 1 : "Ultra-cold vibration control" and in particular on a cryogenic superconducting inertial sensor.

Gravitational wave signals below a frequency of about 10 Hz are obscured by thermal noise in current detectors. Because temperature is the vibration of atoms in some respect, making the distance measurement between the mirror surfaces more challenging, the mirrors of future detectors will need to be cooled down to temperatures around 10 K. We need to control the motion of some of the cold objects, for which we develop inertial sensors that can survive this harsh environment.

CP3 members collaborate mostly with RWTH Aachen (they are preparing a cryostat where we will test the sensor), KUL (we are collaborating to develop cryogenic readout electronics for the sensor) and ULiège (we align our sensor efforts).

External collaborators: C. Collette (Liege), S. Hild (Maastricht), A. Bertolini (Nikhef), A. Gatto (KULeuven) and E-TEST collaboration.
GasToF: ultra fast timing detector
Krzysztof Piotrzkowski

GasToF (Gas Time-of-Flight) detector is a Cherenkov detector developed for very precise (with <10 ps resolution) flight time measurements of very forward protons at the LHC. Such an excellent time resolution allows, using z-by-timing technique, for precise measurements of the event vertex z-coordinate and the background reduction. Such a detector is essential for selecting exclusive and semi-exclusive processes at high luminosity, and can also be applied for the timing and particle ID at future experiments.

Investigate new techniques for ToF-PET.

External collaborators: CMS PPS project, M. Albrow (Fermilab), C. Royon (Kansas), J. Varela (Lisbon), and E. Schnys (Photonis) and J. Howorth (Photek Ltd).
High energy photon-induced interactions
Krzysztof Piotrzkowski

High-energy photon-photon and photon-proton interactions at the LHC offer interesting possibilities for the study of the electroweak sector up to TeV scale and the search for processes beyond the Standard Model. After in-depth exploratory studies, first measurements of two-photon muon pair production were performed as well as first ever observation of W boson pairs produced by photon fusion. Now unique investigations of quartic couplings between photons and W and Z bosons are being pursued.

Surveying the scientific potential of the new e-ion collider at Brookhaven (EIC).

External collaborators: CMS FSQ analysis group, B. Surrow (Philadelphia) and the group of A. Szczurek (Krakow).

Non-active projects
Publications in CP3
All my publications on Inspire

Number of publications as CP3 member: 42 Download BibTeX

Last 5 publications


CP3-20-54: When invariable cross-sections change: the Electron-Ion Collider case
K. Piotrzkowski and M. Przybycien

[Abstract] [PDF] [Full text]
Phys. Rev. D Letter
Refereed paper. November 24.
CP3-20-33: Test beam demonstration of silicon microstrip modules with transverse momentum discrimination for the future CMS tracking detector
CMS Tracker Collaboration

[Journal] [Full text]
Published in: JINST 13 (2018) 03, P03003, Report number: FERMILAB-PUB-18-385-CMS, CERN-CMS-NOTE-2017-010

O. Bondu5, S. Brochet5, A. Caudron5, S. De Visscher5, B. Francois5, A. Jafari5, J. Cabrera Jamoulle5, M. Komm5, G. Krintiras5, A. Magitteri5, A. Mertens5, D. Michotte5, M. Musich5,, L. Quertenmont5, M. Vidal Marono5,
Refereed paper. July 2.
CP3-20-32: Beam test performance of prototype silicon detectors for the Outer Tracker for the Phase-2 Upgrade of CMS
CMS Tracker Group

[Journal] [Full text]
Published 17 March 2020 • © 2020 CERN for the benefit of the CMS collaboration.
Refereed paper. July 2.


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.


CP3-16-13: Evidence for exclusive gamma-gamma to W+ W- production and constraints on anomalous quartic gauge couplings at sqrt(s) = 7 and 8 TeV
Khachatryan, Vardan and others

[Abstract] [PDF] [Journal] [Dial]
Submitted to JHEP
Refereed paper. April 19.

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