CZ+SK HEP 2024 Workshop

22 May 2024, 08:00 → 23 May 2024, 18:00 Europe/Prague

Jiri Kvita (Palacky University (CZ)), Karel Cerny (Palacky University (CZ))

The next volume of annual meetings for the particle physics community from the Slovak and Czech Republic will be organized and hosted by the Joint Laboratory of Optics at Palacky University in Olomouc. The meeting aims to provide a platform for presentations and discussions of results obtained by scientists from both countries in the field of particle physics. Early career scientists and students are encouraged to present their work and introduce themselves to the community.

Wednesday 22 May

09:00 → 09:40 Registration & coffee

09:40 → 10:00 Introduction of Joint laboratory of optics

Speakers: Jiri Kvita (Palacky University (CZ)), Karel Cerny (Palacky University (CZ))

SLO_for_CZSKHEP_May2024.pdf

10:00 → 10:20 Multi-differential dijet cross sections at the ATLAS experiment

Inclusive dijet cross-sections are measured in proton-proton collisions at a center-of-mass energy of 13 TeV. The measurements use a dataset with an integrated luminosity of 139 $fb^{−1}$ recorded in 2015-2018 with the ATLAS detector at the Large Hadron Collider. Jets are identified using the anti-kT algorithm with a radius parameter value of R=0.4. The inclusive dijet cross-sections are measured double-differentially as a function of the invariant dijet mass, covering the range from 240 GeV to 9.5 TeV, first for the half absolute rapidity separation between the two leading jets up to $y^{*}$<3.0 and second for leading and subleading jet boost up to $y_{boost}$<3.0. The results are unfolded to the particle level and compared to state-of-the-art next-to-next-to-leading-order pQCD calculations with full-color approximation corrected for non-perturbative and electroweak effects.

Speaker: Ota Zaplatilek

10:20 → 10:40 Large-R jets calibration in R22+ for AtlFast3 based on FullSim (ATLAS QT)

The aim of the work is to obtain energy response and resolution for large-R jets in AtlFast3 (AF3) in R22+.

Speaker: Matus Kostov (Comenius University (SK))

10:40 → 11:00 coffee

11:00 → 11:25 Fantastic Qubits and how to use them

Speaker: Karel Lemr

fantastic_qubits.pdf

11:25 → 11:45 ATLAS Heavy Ion Programme at Charles University

ATLAS Heavy Ion Programme at Charles University

Speaker: Pavel Vana (Charles University (CZ))

CZSK_HEP_Olomouc24_Vana.pdf

11:45 → 12:05 Bose-Einstein correlations in 3D approach in high energy proton-proton collisions in the ATLAS

The presentation will focus on investigating Bose-Einstein correlations in a 3D approach within 13 TeV proton-proton collisions. Instead of relying solely on a one-dimensional analysis, we will explore the possibility of characterizing the source radius of particles (R) using two or three components. In this context, we discuss various properties of the source emission probability (especially using Levy distribution source model) in relation to the direction. Furthermore, we will present a comparison between unlike-sign and opposite-hemisphere reference samples used to obtain the fit of C2/R2 correlation functions of two identical bosons.

Speaker: Daniel Suchy (Comenius University (SK))

12:05 → 13:45 lunch

In a nearby canteen 17.listopadu.

13:45 → 14:05 Jet Energy Scale from Hadronic W mass in ttbar

Quarks and gluons emerging from the high energy proton-proton collisions at the Large Hadron Collider are observed as jets. Jet energy scale (JES) calibration is employed to correct the measured energy of the jets to that of the truth jets. A new approach, exploiting $t\bar{t}$ events in single-lepton decay channel is used to calibrate JES. The invariant mass of W boson is reconstructed from measured four-momenta of the two jets from hadronically decaying W boson. Forward Folding formula is applied to smear the $p_{T}^{reco}$ of jets depending on their true particle level transverse momenta $p^{truth}_{T}$ and assumed value of the energy scale and resolution. JES value is then extracted by fitting templates representing different scale and resolution assumption in the simulation to the observed distribution of the invariant mass of the W boson. Pure quark jets from the W boson decay tend to have low $p_{T}$, thus the presented method has a potential to significantly improve the JES uncertainty for low $p_T$ jets below 50 GeV. The first sensitivity studies will be presented as well as first data/simulation plots using the new tools available in the Top working group in Release 24.

Speaker: Adriana Dohnalova (Comenius University (SK))

14:05 → 14:25 Observation of top quarks in $p$+Pb collisions at $\sqrt{s_\mathrm{NN}}=8.16\;\mathrm{TeV}$ with the ATLAS detector

Top quarks, the heaviest elementary particles carrying colour charges, are considered to be attractive candidates for probing the quark-gluon plasma produced in relativistic heavy-ion collisions. In proton-lead collisions, top-quark production is expected to be sensitive to nuclear modifications of parton distribution functions at high Bjoerken-x values, which are difficult to access experimentally using other available probes. In 2016, the ATLAS experiment recorded proton-lead collisions at centre-of-mass energy of 8.16 TeV per nucleon pair, corresponding to an integrated luminosity of 165 nb-1. In this poster, we present the final measurement of the top-quark pair production in dilepton and lepton+jet decay modes in the proton-lead system with the ATLAS detector. The inclusive cross section is extracted using a profile-likelihood fit to data distributions in six signal regions. The nuclear modification factor is also measured. The results are compared to theory predictions involving various nuclear parton distribution functions. The total relative uncertainty amounts to 9%, which makes it the most precise top-quark pair cross-section measurement in heavy-ion collisions to date.

Speaker: Santu Mondal (Czech Technical University in Prague (CZ))

CZ+SK 2024 HEP Workshop - Santu Mondal.pdf

14:25 → 14:45 B0 meson lifetime measurement in ATLAS

A novel measurement of B0d meson lifetime with ATLAS full Run-2 dataset is presented. Average decay width Γd as well as the Γd/Γs width ratio are also measured. The measurement results are consistent with the Standard Model predictions and with other experiments.

Speaker: Marek Biros (Charles University (CZ))

14:45 → 15:05 Precision measurements at Belle II

Speaker: Tadeas Wilczek

Precision-measurements-at-Belle-II.pdf

15:05 → 15:25 coffee

15:25 → 15:45 The Cherenkov Time-of-Flight detector in ATLAS

Speaker: Libor Nozka (Palacky University (CZ))

LNozka_ToF.pdf

15:45 → 16:05 Analysis of AFP/ToF data from early LHC Run-3

The analysis of the early LHC Run-3 data was performed. Efficiencies for the ATLAS Forward Proton (AFP) Time-of-Flight (ToF) detector were studied. In addition, these performance studies of the ToF data included the proton-proton vertex reconstruction using matching of ToF and central ATLAS vertex position. After a calibration, a preliminary resolution of the vertex reconstruction was determined with a low-mu ATLAS run.

Speaker: Viktoriia Lysenko (Czech Technical University in Prague (CZ))

CZ+SK_22_05_22_ToF_Lysenko.pdf

16:05 → 16:25 Performance of AFP/ToF detector in Run 2

A brief summary will be given accounting on results obtained from a analysis of the very first data recorded by the AFP Time-of-Flight detector in 2017.

Speaker: Karel Cerny (Palacky University (CZ))

ToFCZSK2024.pdf

16:25 → 16:45 Application of Machine Learning Based Top Quark and W Jet Tagging to Hadronic Four-Top States Induced by SM as well as BSM Processes

Speaker: Petr Baron (Palacky University (CZ))

CZSK2024_ML_4top.pptx.pdf

16:45 → 17:05 coffee

19:00 → 23:00 Conference dinner

Thursday 23 May

09:00 → 09:30 coffee

09:30 → 09:45 History of CZ+SK meetings

Speaker: Jiri Kvita (Palacky University (CZ))

Intro_JiriKvita_CZSK_May2024.pdf

09:45 → 10:05 Focus topics for the ECFA study on Higgs / Top / EW factories

I'll try to describe some concrete studies in areas where further work would be beneficial towards fully understanding the physics potential of an e+e− Higgs / Top / Electroweak factory at the FCC as described in the https://arxiv.org/abs/2401.07564

Speaker: Zdenek Hubacek (Czech Technical University in Prague (CZ))

prez_czsk24_focus.pdf

10:05 → 10:25 Neutrinos with Hype-K (and WCTE)

Speakers: Bedrich Roskovec (Charles University (CZ)), Jiri Kvita (Palacky University (CZ))

HyperK_WCTE_CZSK_May2024.pdf

10:25 → 10:45 coffee

10:45 → 11:05 Collisions of light at the LHC

Speaker: Martin Rybar (Charles University (CZ))

CZSK_Olomouc_2024_Rybar.pdf

11:05 → 11:25 Bump hunting in B-physics at ATLAS

Speaker: Pavel Reznicek (Charles University (CZ))

CZSK_4muon_23.5.2024.pdf

11:25 → 11:45 Time calibration of the ATLAS Tile Calorimeter

Speaker: Tomas Davidek (Charles University (CZ))

tile_time_summary.pdf

11:45 → 12:00 Closing remarks

Speakers: Karel Cerny (Palacky University (CZ)), Jiri Kvita (Palacky University (CZ))

12:00 → 13:30 lunch