jan p. nassalskirecfa, warsaw, 25.02.20051 polish participation in fixed target experiments at cern...
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![Page 1: Jan P. NassalskiRECFA, Warsaw, 25.02.20051 Polish participation in fixed target experiments at CERN (1999-2004) NA48 & NA48.1 running NA49 NA59 (COMPASS)](https://reader038.vdocuments.net/reader038/viewer/2022110102/56649f155503460f94c2a62b/html5/thumbnails/1.jpg)
Jan P. Nassalski RECFA, Warsaw, 25.02.2005 1
Polish participation in fixed target experiments
at CERN (1999-2004)
NA48 & NA48.1 running NA49 NA59 (COMPASS) NA47 (SMC) running WA98 completed
J.P.Nassalski25.02.2005RECFA, Warsaw
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 2
Sources of funds
Budget of Institutes: - salaries of physicists and PhD students, - all overheads: electricity, heating, phones, faxes… (ex.: average for SINS: 42kzł (10.4kЄ) /year / <person>) It will be not accounted for in experimental budgets.
Funds for „Special Projects and Equipment” (SPUB) from the fundning agency (KBN): - building detectors, - contributions to Common Funds, - travel, - local infrastructure (computers, …), - supplements to salaries.
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 3
Grants from KBN (typically 100kzł /year in total): - can not be used for Common Funds, - used to supplement SPUB for specific items, - there are special grants to support PhD students and young researchers.
Funds from bilateral agreements (PL-D, PL-F, …): used for the exchange of physicists between collaborating Institutes.
Funds from EU.
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 4
NA48
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 5
Soltan Institute for Nuclear Studies:
High Energy Physics Department, Department of Nuclear Detectors and Electronics
Institution
Participants 4 physicists 2 electronics engineers 1 PhD student 1 diploma student
only 1 physicist continued in NA48.1
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 6
Year: 1999 2000 2001 2002
kzł:
(1Є=4zł)
53 113 165 145+32a
40% common funds, 24% travel, 17% overheads, 13% salaries, 5% equipment, …
In addition: 1 PhD grant of 23kzł.
a) Common fund for NA48.1
Budget for experiment(does not include personnel costs covered by Institutes)
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 7
Hardware responsabilities
Design, making a prototype, testing after production and maintenance of:
60 modules of Fastbus Clock Fanout, 65 modules of Fastbus Optoisolated Cluster Interconnect, 30 modules of VME FOL-RIO Interface.
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 8
Contributions to physics analysis Parallel analysis for:• search for light gluino,• 1 PhD,• KS lifetime,•
Contributions to systematics:• 1 diploma,
η and K0 mass.Re(ε /ε) :
+ - + -L,SK π π e e :
± 0L e eK π π e ν (ν ).
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 9
Highlights World data on ε /ε
COMBINED RESULT FROM ALL EXPERIMENTS:
εε’/’/εε = (16.6 = (16.6 ±± 1.6) 1.6) ·· 10 10-4-4
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 10
K0, η masses and K0 lifetime
s
10K ππτ (0.89598 0.00048 0.00051) 10 s
In 2002:
• higher precision than that of PDG2000 and 1.7σ above it,
•
consistent with PDG2000 and with a similar error,
•
2.4 times higher precision than that of PDG2000 and it differs from it by 4.2σ.
0 0LM(K 3π ) 497.625 0.031 MeV
0M(η 3π ) 547.843 0.051 MeV
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 11
0 ± 0L e eK π π e ν (ν )
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 12
Event display:~1200 charged particles
NA49Large Acceptance Hadron Spectrometer for the study
of Heavy Ion Collisions
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 13
Institutions
Soltan Institute for Nuclear Studies (SINS), High Energy Physics Department, Warsaw,
Warsaw University (WU), Institute of Experimental Physics,
Institute of Nuclear Physics, Polish Academy of Science (INP), Kraków,
Świętokrzyska Academy (SA), Kielce (since April 2002).
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 14
Participants (2005)
Institution Physicists PhD students
Diploma students
SINS 2
1
WU 1 1
INP 3 1
SA 5
2 2
Total 11 5 2
10 students obtained diploma in 1998-2005
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 15
Budget for experiment(does not include personnel costs covered by Institutes)
Year:
Institute:
1999 2000 2001 2002 2003 2004
(SINS+
WU+INP)a 51 43 81 201 193 120
SAb - - - 190
In addition:a) 3000Є from PL-D b) 75kЄ from Helmholtz Gemeinschaft (2004-2006)
30% travel, 27% salaries, 16% equipment, 16% overheads, …
kzł
kzł
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 16
Main results
First beam 1996, last 2002, analysis goes on.
Main goal: search for QGP in HI collisions
Main results (whole collaboration):• Strangeness enhancement in central Pb-Pb
collisions,• Collective behaviour (HBT, flow),• Non-monotonic energy dependence of
strangeness production.
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 17
Main results of Cracow & Warsaw groups:
1) Evolution of baryon stopping from
p-p to p-Pb to Pb-Pb,
2) Non-statistical fluctuations in pt,
3) Nuclear modification factor in p-Pb.
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 18
Evolution of net baryon number:
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 19
Nuclear modification factor in p-Pb
pApA
pp bin
σR =
σ <N >
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 20
Kielce group in NA49 collaboration
The group was involved in collecting the data at the SPS and now it participates in the data analysis. It is responsible for the magnetic field calibration via K0 mass reconstruction and the recalibration of the Veto calorimeter. The group performs the analysis to determine:
• fluctuations of multiplicity & pT ;
• collective flow of hyperons;
• production of K0*.
In October 2004 the group organized the International Workshop on Future of Nuclear Collisions at High Energies.
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 21
NA58COMMON MUON and PROTON APPARATUS for STRUCTURE and SPECTROSCOPY
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 22
Soltan Institute for Nuclear Studies (SINS), High Energy Physics Department,
Warsaw University (WU), Institute of Experimental Physics,
Warsaw University of Technology (WUT), Institute of Radioelectronics.
Institutions
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 23
Institution Physicists/Engineers
PhD students
Diploma students
SINS 5
3 1
WU 1 2 1
WUT 2 3
Total 8
8 2
Participants (2005)
One PhD student from SINS graduated in 2004 andleft COMPASS.
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 24
Year:
Institute:
1999 2000 2001 2002 2003 2004
SINS+WU 385 359 518 505 359 649
WTU 197 212 127 150 - 127
32% travel, 22% common funds, 19% overheads, 16% salaries, 6% equipment, …
In addition: 2 PhD grants, 50kzł in total, „Polonium”, Saclay-SINS, 1.7kЄ for travel in 2004.
Budget for experiment(does not include personnel costs covered by Institutes)
kzł
kzł
180kzł shared between COMPASS and SMC.
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 25
Contributions to hardware
Construction of an additional SciFi detector to be used for tracking in the beam region (from 2006).
Contributions to general purpose software
Alternative algorithm of track reconstruction, Alignment of data taken in 2002 – 2004, Implementation of additional scintillator hodoscopes
used to determine beam momentum, Radiative corrections and dilution factor.
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 26
Physics program of COMPASS(as in the Proposal)
Nucleon spin structure, using muon beam:
Gluon polarisation ΔG(x)/G(x), Quark polarisation of different flavours Δq(x), Transverse spin distribution function ΔTq(x), Spin-dependent fragmentation function ΔDq
Λ..
Hadron spectroscopy, using hadron beams:
Primakoff reactions, Polarisability of π and K, Glueballs and hybrids, Semileptonic decays of charmed hadrons, Double-charmed barions.
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 27
Contributions to physics analysis
ΔG(x)/G(x) from events with hadron pairs at large pt,
ΔG(x)/G(x) from events with D*,
Search for Φ(1860) pentaquark (parallel analysis),
A1d at small x and Q2 (parallel analysis),
Spin matrix elements for exclusive ρ0 production (parallel analysis),
A1d for exclusive ρ0 production (parallel analysis),
A1d for identified hadrons.
Warsaw group has experience from previous CERN muon experiments:EMC NMC SMC COMPASS.
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 28
ΔG/G from large pt
ΔG/G = 0.06 ± 0.31stat. ± 0.06syst.2002/03 dataQ2 > 1 GeV2
GSA,B,C: T. Gehrmann and W. Sterling, Z. Phys. C65 (1994) 461.
<xg> = 0.13 ± 0.08
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 29
D0 signal ( ΔG)
D* D0πs (Kπ) πs
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 30
2002/03 dataQ2 > 1 GeV2
x·g1d(x)
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 31
Prospects
The only fixed target experiment considered so far for running in mid-term planning (2006-2010) at CERN.
Possible new item in the future physics program: measurements of GPD (within the EU „Hadron Physics”):
polish group contributes 73kЄ in 2004-2006 to build a prototype of recoil detector
as a joint project of Bonn, Mainz, Saclay and Warsaw.
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 32
NA47(SMC)
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 33
End of data taking: 1996.
Institutions: SINS (5 physicists + 1PhD), WU (1 + 1PhD), WUT (2 engineers),
Experimental budget in the reporting period: in 2000-2003, 180kzł shared between SMC and COMPASS,
5 publications since 1999: 3 technical + 2 on physics: 1999: A1
p,d at small x and Q2 , 2004: ΔG/G from events with hadrons at large pt. In both cases – a major role in the analysis (1 PhD from each activity).
All of physicists are now in COMPASS.
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 34
Low x trigger implemented by Warsaw group
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 35
WA98
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 36
End of data taking: 1996,
Institutions: SINS (3 physicists +1PhD), SA (1 pysicist), WUT (1 engineer); 2 PhDs*)
Experimental budget*): 200kzł.
~20 publications*).
-------------------- *) in 1999-2004
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 37
Interferometry of Direct Photons in Central 208Pb+208Pb Collisions at 158AGeV, Phys. Rev. Lett. 93(2004)022301
Two-particle correlations of direct photons were measured in central 208 Pb+ 208 Pb collisions at 158 AGeV. The invariant interferometric radii were extracted for 100 < KT < 300 MeV/c and compared to radii extracted from charged pion correlations. The yield of soft direct photons, KT < 300 MeV/c, was extracted from the correlation strength and compared to theoretical calculations.
FIG. 4: Yield of direct photons extracted from the strength of the two-photon correlation (closed circles) and by the statistical subtraction method (open circles, or arrows indicating upper limits) [6]. Total statistical plus systematical errors are shown.
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 38
One-, Two- and Three-Particle Distributions from 158A GeV/c
Central Pb+Pb Collisions, Phys. Rev C67(2003)014906
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 39
Thank you
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 40
Large CPV effect seen in ...
KL π+π-e+e- , confirming KTeV result:
AΦ = (14.2 ± 3.6)%
AΦ = (13.6 ± 2.8)%
BR = (3.08 ± 0.20) ·10-7
BR = (3.2 ± 0.7 ) ·10-7
in agreement with predictions.
... but not in KS π+π-e+e- (only NA48 data):
BR = (4.69 ± 0.30) ·10-5AΦ = (0.5 ± 4.3)%
as expected, indicating that AΦ ≠ 0 in KL is genuine effect.
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Jan P. Nassalski RECFA, Warsaw, 25.02.2005 41
Evolution of non-statistical pt fluctuations with centrality: