future experiments with hades at fair
DESCRIPTION
Future Experiments with HADES at FAIR. Pavel Tlustý , NPI Řež. “near future” - experiments on SIS18 in 2010-2015? - upgrade of the HADES spectrometer experiments with HADES on SIS100 at FAIR in 2016-. June 24, 2010. CHIRAL 2010 workshop, Valencia, June 21-24, 2010. - PowerPoint PPT PresentationTRANSCRIPT
Future Experiments with HADES at FAIR
Pavel Tlustý, NPI Řež
• “near future”
- experiments on SIS18 in 2010-2015?
- upgrade of the HADES spectrometer • experiments with HADES on SIS100 at FAIR in 2016-
CHIRAL 2010 workshop, Valencia, June 21-24, 2010 June 24, 2010
2
2.2 GeV (2004)
„Anomalous” excess of e+e- pairsat intermediate masses verify DLS data
NN bremsstrahlungand Dalitz decays
vector mesons / in-medium
p+p
Resonance (,N*) production, formfactors and studies of / Dalitz decays (helicity angles)
C+C
2.0 AGeV (2002)
1.0 AGeV (2004)
1.
p+p
1.25 GeV (2006)
d+p
1.25 GeV (2007)
2.
Ar+KCl
1.76 GeV (2005)
Evolution of e+e- yieldStrangeness: , K±,0,
3.
3.5 GeV (2007)
p+Nb
3.5 GeV (2008)
p+p 4.
Completed physics program
3
Yield/Apart
Ar+KClCa+Ca
Observed systematics of “excess"
Scales with Ebeam like production Scales with Apart stronger than
linear:
≈ <Apart>1.4
“Excess” vs. beam energy and system size
Vector mesons
• larger system – better precision needed for differential studies• reference spectrum (NN)- peripheral reactions, d+p, ?• can one see in-medium effects on vector meson?
5
Ar+KCl data compared to IQMD
K0 - N potential
Data compared to the IQMD. Version with potential preferred.Consistent with KN-potential with a strength of U=39 MeV @ =0
extrapolation from high density to 0 (IQMD)
+A & p+A data (FOPI & ANKE)
consistent with U = 205 MeV at =0 extrapolation from low density to 0 (HSD)
Kaon flow
2cos2cos21 21 vvddN
sideward out-of plane(eliptic)
Y. Shin et. al. (KAOS)PRL 81 (1998) 1576
W. Cassing et al., NPA 727 (2003) 59, E. Bratkovskaya, priv. com.Coupled channel G-Matrix approach (K- spectral functions): L. Tolos et al., NPA 690 (2001) 547
K+
Kaon flow
2cos2cos21 21 vvddN
sideward out-of plane(eliptic)
W. Cassing et al., NPA 727 (2003) 59, E. Bratkovskaya, priv. com.Coupled channel G-Matrix approach (K- spectral functions): L. Tolos et al., NPA 690 (2001) 547
M. Płoskon, PhD Thesis, Univ. Frankfurt 2005
Physics Program on SIS18 – Heavy Ions
combined measurement of dielectron and strangeness production
in heavy systems
• Dielectrons: Studies of properties of the low-mass, i.e. 0.14 < Me+e− < 0.5
GeV/c2 dielectron excess Vector meson (ρ/ω/φ) spectroscopy in the dielectron channel
• Strangeness: φ meson production via the K+K− decay channel K0, K+ and K− production characteristics by means of transverse
momentum, rapidity and flow measurements Studies of strange baryon production: Λ(1115),Σ(1385) and Ξ−(1321) Search for kaonic clusters Studies of HBT correlations
9
Hades Upgrade ProjectAim: heavy systems at SIS18 and SIS100
RPC performance (beam test) Efficiency above 95 % Time res. 50-80ps Negligible crosstalk < 1%
List of HADES upgrade subprojects:
RPC - Resistive Plate Chamber FINISHED Time res. 50-80ps, high granularity
Forward Wall FINISHED range 0.2 – 7 degrees, reaction plane
DAQ-Upgrade (RICH, MDC, FWALL, TOF, SHOWER) goal 20kHz for Au+Au LVL1 ON GOING MDC I rebuild system stability FINISHED
End of 2010: HADES ready for heavier systems
Multipurpose Trigger Readout Board TRB:4 TDC – 128 channels (HPTDC), 4x512Mb SDRAM, FPGA – Virtex4LX40,
ETRAX, FS – 4 processors, 100Mb/s,TCP/IP, 2,5 Gb/s optical link, DSP TigerSharc, DC/DC converters,
10
Simulations – tracking study
Tracking ready to be used in high multiplicity environment
Secondary vertex reconstruction not ready
Tracking optimization on-going
to be verified with HI beam
11
A Large excess (~8) expected from Ar+KCl excess scaling above the NN reference
Differential studies of excess possible: centrality, dN/dmt , angular distributions…
Triggers for peripheral and central reactions. Use peripheral reactions for a
comparison with the NN reference.
(pp+pn)/2
Dalitz
o
baryonic radiation
Collision systems for HI runs:Highest possible energy
high VM and strangeness production
Largest possible colliding systems
increase compression and medium effects
Au(71+) - 1.25 AGeV - similar to pp, np data
Ag(46+) – 1.65 AGeV - comparable with Ar+KCl
(1.75 AGeV)
Medium effects for intermediate masses
12
Sensitivity to medium effects for VM
VM in HI coll. : regeneration and absorption - Ne+e- ~ e+e- Tfireball
HSD + Dropping mass & mass broadenning
AGeVAGeV
AGeV
trigger (25% ot total cross section) with 10 KHz
• Ag+Ag : maximal density VM production rate• direct comparison to Ar+KCl possible
Strangeness : count rate estimates
• counts/day for semicentral LVL1 assuming efficiencies & production rates from ArKcl• 20-100 more than in ArKcl ~ ! ! ! - acc(RPC) x trigger rate (no LVL2 )
Simulations: strangeness K- identification
acceptance purity (no dE/dx used)
• large acceptance: mid rap. coverage• very good K- purity up to pt < 800 MeV/c
Beam/target and Trigger setting, Shift request
• Two beam/target combinations 197Au + 197Au at 1.25 A GeV
107Ag + 107Ag at 1.65 A GeV
• Beam intenisty ~2*107/spill(5s)
• 1% interaction target (12 segments)• LVL1 trigger settings (~20 kHz total): minimum-bias semicentral (25% total cross section) • Shift request:
Au + Au 35 + 5 days (120 shifts)
Ag + Ag 45+ 5 days (150 shifts)
16
FAIR facility at GSISIS100 beam energies: ions up to 14 A GeV (Au79+ – 11.2 AGeV) protons up to 29 GeV
Module Construction time (months)
Ready for installation
0 72 2015 / 16 1 28 2015 / 16 2 60 2016 3 60 2016
B. Sharkov+1 year+1 year
17
HADES/CBM cave design
W. Niebur
18
Di-electrons at SIS100 (2-10 AGeV), motivation
No di-electron data exist in this energy range Extension of the HADES physics program Enhance production of Vector Mesons:
SIS18 SIS 100 subthreshold production above threshold better signal, precise line shape determination reference data for SIIS300
S. Vogel et al.Phys. Rev. C78 044909 (2008)
2AGeV
11AGeV
30AGeV
HADES at SIS100: - running experiment, well understood performance - currently conducted upgrade will improve stability, DAQ and time resolution of the Spectrometer - easy transfer to FAIR, experienced crew - can deliver high quality data
19
Di-electrons at SIS 100 e+e− acceptance
Acceptance for di-electrons from ω->e+e− (2 AGeV and 8 AGeV)
Direct ω decay: PLUTO, ω from thermal model Single leptons filtered with HADES acceptance 90 opening angle cut was applied
Acceptance:2 AGeV 33 %8 AGeV 21 %
Number of 's in acceptance increase by a factor of ~50
20
Di-electrons at SIS 100 – invariant mass
Di-electron invariant mass for various systems:( C+C 2 AGeV and 8 AGeV, Au+Au 1 AGeV and 8 AGeV )
All dilepton sources generated by PLUTO, hadronic and electromagnetic decays Single leptons filtered with HADES acceptance Lepton momentums smeared 90 opening angle cut was applied
1.0 AGeV
Realistic simulationin preparation
21
Hadrons at SIS 100 – acceptanceURQMD and PLUTO events filtered with HADES acceptance
midrapidity covered at both 2.0 and 8.0 AGeV 15 % reduction at 8 AGeV for π 40 % reduction at 8 AGeV for K
8 A GeV
2 A GeV
22
Occupancy estimation at 8 AGeV
Simulated events Central Au+Au at 1.5 AGeV and 8 AGeV, C+C at 2.0 AGeV and 8 AGeV HGeant used for a realistic detector modeling
Main outcome From C+C at 2.0 AGeV Au+Au at 1.5 AGeV (SIS18) - factor of 14 At Au+Au at 1.5 AGeV expected 20% double hit probability !!!
corresponds to Ni+Ni at 8 AGeV - heaviest system at SIS 100
23
Calorimeter project For pair excess determination a precise knowledge of the hadronic cocktail is needed (particle yields at chemical freeze-out)
At 2-40 AGeV mainly dominated by η-Dalitz Normalization to π0 (at SIS18 – TAPS data)
Calorimeter for HADES π0, η measurement improved pion suppression
Side View
START
Electromagnetic calorimeter for HADES (2011- ...) substitute for Pre-Shower (18º<Θ<45º, 8 m2;18 tons) el/ separation, º and η Dalitz, ...
24
Calorimeter project
Millstones achieved: Test at MAMI, lead glass modules from OPAL
energy resolution for photons K. Lapidus, Eliane Epple, simulation the parameterization lookup table almost ready, detailed, fast simulation will be possible Mechanical construction – general concept ready, approved by HADES construction engineer, U. Kopf
5.4% / sqrt(E)
25
Calorimeter projectMillstones achieved: Measure the pion rejection and compare
this to the simulation HADES ECM test in CERN T10 (F.Guber), HADES – NA61 collaboration May 24 - 31.
Millstones to be achieved: FE electronics pi0 reconstruction in beam test
26
Summary and outlook Di-electron radiation from the HI collision at SIS 18 is being investigated in a very systematic, model independent way.
No medium effects observed for light systems (C+C) The "reference spectrum" based on elementary reactions established
for heavier systems (Ar+KCl) First VM signal measured at SIS 18 in Ar+KCl collisions Modification of the meson properties in-medium (p+Nb) under investigation
Interesting physics program for future proposals of HADES at SIS 18( Au+Au, Ag+Ag, − beam )
SIS100 – a natural way of the physics programme extension The device is ready to take high quality data Easy installation at SIS 100 VM produced above the production thresholds High acceptance for direct decays of VM over whole energy
regions of SIS 18 and SIS100 (from 33 % at SIS 18 to 22 % at SIS100) Waiting for FAIR . . . 2016-2017 ....
27
The HADES CollaborationCyprus:Department of Physics, University of Cyprus
Czech Republic:Nuclear Physics Institute, Academy of Sciences of Czech Republic
France:IPN (UMR 8608), Université Paris Sud
Germany:GSI, DarmstadtFZ Dresden-RossendorfIKF, Goethe-Universität FrankfurtII.PI, Justus Liebig Universität GiessenPD E12, Technische Universität München
Italy:Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del SudIstituto Nazionale di Fisica Nucleare, Sezione di Milano
Poland:Smoluchowski Institute of Physics, Jagiellonian University of Cracow
Portugal:LIP-Laboratório de Instrumentação e Física Experimental de Partículas
17 institutions120members
Russia:INR, Russian Academy of ScienceJoint Institute of Nuclear ResearchITEP
Spain:Departamento de Física de Partículas, University of Santiago de CompostelaInstituto de Física Corpuscular, Universidad de Valencia-CSIC
28
Backup slides
Kaonic Nuclear clustersStat. model predictions for cluster formation in Au-Au collisions
promising candidate ?: K- pp system
• predictions from theory : 20-70 MeV binding
energy , hadronic decay into p• experimental evidences : FINUDA K- absorption on nucleus M (p) = 2255±7 MeV/c2 , = 67 ± 14 MeV/c2
M. Agnello et al., PRL 94, 212303 (2005).
DISTO p + p -> K+ + X X-> p
MX = 2265 ± 2 (stat) ± 5 (syst) MeV/c2 X = 118 ± 8 (stat) ± 10 (syst) MeV/c2
RMS radius of (p) < 1.7 fm !
Y. Yamazaki et al..arXiv:1002.3526
• R. Kotte : (p) source in ArKcl
but no sensitivity to p potential and ..no signal in p inv. mass visible
30
Experiments with pion beamsThe GSI secondary pion beam
line
Mom. det. of the beam particles with precision 0.3% for exclusive reconstruction Tracking in the beam line needed: silicon strip detector
31
Pion beam project - beam detectors
Beam tracking Si detectors (TU Munich) Two 10cm x 10 cm sensors (P-Type) arrived,
Radiation hard 1 Megarad level – to be verified !!! Electronics designed by W.Koenig, partially produced,
2 versions will be tested at Munich:- discreet version, TRB based system Robert Münzer - nXyter version: Rafal Lalik
32
Di-electrons from π− induced reactions at SIS18
M.E
ffen
berg
er e
t al.
nucl
-th/9
9010
39
π−+ A – inclusive ω measurement
-p boundn e+e-n;
pe+e-< 300 MeV/c; „at rest”
Exclusive measurement • large cross-section
off-shell ρ/ω coupling to S11(1535) and D13(1550) M.Soyeur et al., nucl-th/0003013
- p (ω/ρ)n e+ e- n − selection of ρ and ω − η-> e+ e-, π0π0, ... suppression by missing mass technique.
Beam particle tracking is essential, in preparation
cGeVpmbnptot /[email protected] =
cGeVpmbXpp ptot /[email protected]
cut on missing mass of e+ e- (nutron ); e+e- suppressed!