1. Slovakia at CERN CERN member state from 1993
Branislav Sitár
Bratislava, March 24th 2015

2. Slovak institutions currently active in particle physics
Žilina Žilinská Univerzita
Košice Institute of Exp. Physics SAS
University of P.J.Šafárik
Banská Bystrica Univerzita Mateja Bela
Bratislava
Institute of Physics SAS
Univerzita Komenského
80 CERN users, including 45 students and young physicists
22 long-term positions of Slovaks at CERN

3. Organization of Slovak membership at CERN
Responsible bodies:
Science and Funding agency:
Ministry of education, science, research and sports
Political: Ministry of foreign affairs
Advisory and initiative body:
Committee for co-operation of Slovakia with CERN
22 Slovak permanent or long term positions at CERN
Karel Šafařík – physics co-ordinator on the ALICE experiment
Peter Chochula – ALICE control system
Marian Ivanov- tracking on ALICE TPC
Pavol Stríženec – ATLAS calorimetry and data processing

4. Slovak activities at CERN
Experiments:
Past: Present:
NA34/3 HELIOS ATLAS
DELPHI ALICE
WA ISOLDE
WA NA62
NA57
NA49
Theory
Activities are regulated according long-term concept of Slovak involvement at CERN

5. Atlas: Slovak hardware contribution
Comenius Univ. Bratislava
IEP SAS Košice 5

6. ATLAS hadron calorimeter - TileCal
Preparation/construction of TileCal
Tests of photomultipliers
Test Beam
Testing production modules on particle beams
Reconstruction response of the Tile modules to hadrons and muons to check energy resolution, linearity, EM scale
Commissioning
LVPS (low voltage power supply) installation
Checking functionality and performance of the Tile modules by data quality monitoring
Maintenance
Production and testing new LVPS
Data quality monitoring 6 6

7. Contribution of IEP SAS Košice to ATLAS7

8. Top charge via top decay products’ charges
SM (Qtop = 2/3):
exotics (Q = -4/3):
for top quark determination
- Charge of W via its lepton decay
Determination of b-jet charge
Correct lepton – b-jet pairing
Outcomes of experiment for SM and XM
data
Combined
charge:
<0: SM
>0: Exo
0.7 fb-1: ATLAS-CONF 5 exclusion XM
2fb-1: Draft 2: ATLAS-TOPQ at pubCom (>8) 8 8

9. Bose-Einstein correlation at 7 TeV
BEC effect: a consequence of wave function symmetry  enhancement in two identical boson correlation function when the two particles are near in momentum space
Plane wave approach for Gaussian emission source :
R is the source radius
 is the incoherence factor (0,1) introduced empirically
Q2 = -q2 =(p1-p2)2  two track four momentum difference
2-
Example of C2 function
BEC effect
Free of BEC - a problem!!!
Pairs of unlike-sign tracks
In experiment:
Contains BEC effect
like-sign track pairs
P(p1,p2)  pravdepodobnost dostat pri sucasnom 2-casticovom merani hodnoty hybnosti p1 a p2.
P(pi)  pravdepodobnost pri jedno casicovom merani.
Fitting C2 R inferred (hadronization radius)
Draft 1: ATL-COM-PHYS at EB, in approval process 9 9

10. ALICE Inner Tracking System: Silicon Pixel Detector
Contribution of IEP SAS Kosice
Router for SPD
A system consisting of 20 9U VME boards
provides communication between the SPD
(~10 million channels) and the CTP,
DAQ and DCS.
Logic was implemented in the FPGA's
JTAG controller for SPD
An electronic module used
for configuration and monitoring
of each pixel chip in the SPD.
Logic implemented in FPGA.
24 modules built. Used in pixel
detector testing systems

11. ALICE Trigger TTCit module Abort gap charge measurement
A module for monitoring and
debugging of the trigger
signal traffic between
the CTP detectors.
IEP SAS Kosice
Abort gap charge measurement
Extending functionality of the Luminosity
monitor for the back-up measurement
of the abort gap charge
Luminosity monitor
On-line processing data
from the Central Trigger
Processor provides
independent Luminosity
measurement and
Luminosity for individual LHC
bunches.

12. Study of the Strange Particle Production
ALICE Kosice team
2 PhD Theses defended,
1 PhD Thesis being completed
Results: Λ/K0S increases with the
centrality of the Pb-Pb collisions
Observed increase of baryon-meson
ratio confirms and complements
measurements by Star and Phenix
experiments at RHIC.
Increase of relative baryon production is significant in the
intermediate pT region: 2 GeV/c< pt <6 GeV/c.
Pb-Pb results converge to a pp results with decreasing
collision centrality (sensitivity to the size of the colliding system)
Peter Kalinak Strangeness in Quark Matter 2011, Cracow, Poland, September 18-24

13. ALICE experiment – contribution of FMFI UK group
Winding machine
Production of IROC
in a high precision Assembly system
Production of 26 ALICE TPC IROC detectors
in Detector Lab. at FMFI UK Bratislava

14. Test bench in Bratislava Detector Lab.
for TPC IROC tests.

15. Installation of the Alice TPC
Slovak physicists and engineers took part in the Alice TPC installation at CERN

16. Reconstruction of a Pb-Pb interaction with the energy 2
Reconstruction of a Pb-Pb interaction with the energy 2.67 TeV/nucleon in the Alice detector
Part of the tracks are reconstructed by means of IROC detectors produced in the Detector Laboratory at FMFI UK Bratislava

17. Anti-baryon to baryon ratios in pp, p-Pb and Pb-Pb collisions
at 2.76 TeV and 5.02 TeV energies mesured by ALICE

18. New set-up for ALICE TPC upgrade in Detector laboratory on FMFI UK Bratislava
Electronics and gas mixing panel
High power
UV Nd-YAG laser
Special TPC chamber for ion drift and ion difussion measurements

19. World LHC Computing Grid cluster at FMFI Bratislava
2015 year: nods, 904 cores, 400 TB data storage
3.9 million jobs processed 19

20. World LHC Computing Grid cluster at IEP SAS Košice
2015 year: cores, 760 TB data storage
1.5 million jobs processed in 2015 20

21. ISOLDE@CERN Proton beam RA beam
Most intense radioactive beams in the world of very high purity.
Possible acceleration up to the 3 MeV/u
(after the HIE-ISOLDE upgrade up to the ~10 MeV/u)
Great possibility to study very rare exotic nuclei and processes.
Proton beam
RA beam

22. Shape coexistence in atomic nuclei
IS521: Simultaneous spectroscopy of γ rays and conversion electrons: Systematic study of E0 transitions and intruder states in close vicinity of mid-shell point in odd-Au isotopes
Spokesperson M. Venhart , Institute of Physics, Slovak Academy of Sciences, Bratislava
Shape coexistence in atomic nuclei
Existence of excited states with different deformation in the same nucleus
Illustrative example: 186Pb: Triplet of differently shaped 0+ states was observed at low-energy (< 500 keV)
WITHOUT UNDERSTANDING OF SHAPE COEXISTENCE WE DON’T UNDERSTAND ATOMIC NUCLEI AT ALL
4 days of beam time approved by the INTC 22

23. NA62 Experiment: for Local Trigger Unit (LTU) + TTCex TTC interface
Ultra-rare Kaon Decays as K+→π+νν
Participating Institute: Comenius Univ. Bratislava
First Data to be taken at CERN in Fall 2014
Contributing with:
Complete Software Development and Its Maintenance
for Local Trigger Unit (LTU) + TTCex TTC interface
Contributions towards Software Production
for the Level-0 Trigger and Run Control of the Experiment
In 2012 Slovak Minister of Education signed a contract with Comenius University Bratislava to take part in the NA62 Experiment which wants to study rare kaon decays. The goal is to test the Standard Model predictions and to search, indirectly, for new physics beyond the Standard Model by looking for excess events.
At present, the key Bratislava activity is in development of software for the TTC (trigger, timing and control) to support two main roles of the TTC interface:
distribute properly synchronized time and trigger signals, and
provide emulation of trigger sequences for testing front-end electronics of the subdetectors
Contribution towards Physics Analysis
Decay Amplitude Analysis in Standard Model and Theories that extend it 23

24. for Local Trigger Unit (LTU) + TTCex TTC interface
Software Development
for Local Trigger Unit (LTU) + TTCex TTC interface
COMPLETED beta version
LTU Board for
each subdetector
In 2012 Slovak Minister of Education signed a contract with Comenius University Bratislava to take part in the NA62 Experiment which wants to study rare kaon decays. The goal is to test the Standard Model predictions and to search, indirectly, for new physics beyond the Standard Model by looking for excess events.
At present, the key Bratislava activity is in development of software for the TTC (trigger, timing and control) to support two main roles of the TTC interface:
distribute properly synchronized time and trigger signals, and
provide emulation of trigger sequences for testing front-end electronics of the subdetectors
14 subdetectors
testing setup
LTU goal is to enable two TTC regimes:
global: communication of properly synchronized trigger info to subdetectors
standalone: emulation of trigger to debug communication with frontend electronics 24

25. Education and trainings at CERN
Doctoral Student Program
Technical Student Program
Summer Student Program
In and 2014 worked in Slovakia very successful grant support for students and young physicists, which was used by ~ 20 students per year. It considerably increased the level of PhD thesis in HEP defended in Slovakia
CERN offers courses for physics teachers and talented students in Slovak language lasting usually one week. Slovak physicists at CERN, namely Karel Šafařík, Peter Chochula, Jan Pišút and others are organizing them on a high level

26. Benefits of Slovak membership at CERN
Slovak membership at CERN brings to our physicists possibility to work on the highest level scientific research
It is pushing up not only scientific, but also technological level in the country
It is a great opportunity for Slovak industry to participate on the supply contracts to CERN. SR reached a high return coefficient
The technology transfer form CERN to Slovakia can be attractive, but is not fully used yet
Possibility of using WLCG gives to our institutes practically non-limited CERN oriented computational power
Within 22 years Slovak physicists reached at CERN large experience and also outstanding scientific results