1. HADES at FAIR
P. Salabura
Jagiellonian University Kraków

2. HADES at SIS100 + Side View ECAL for SIS100 (E)=6%/E FW
START FW
ECAL for SIS100
arxXiv:
(E)=6%/E +
Spectrometer with M/M - 2% at /
Particle identification e//p/K– combined RICH, dE/dx (MDC) and TOF : tof ~80 ps(RPC)
electrons : RICH (hadron blind), TOF, RPC/Pre-Shower -> to be replaced by lead glass (OPAL) ECAL
new ! : photons (18-450) ECAL
Operates since 2002: Upgrade(2010): new DAQ (20 KHz Au+Au collisions)

3. Study of hadron properties in dense baryonic matter
The case of Large B and moderate T :
interesting region in phase diagram not probed experimentally by means of rare penetrating probes.
SIS100 : Continuation of Physics Programme at SIS18
L. McLerran, R.D. Pisarski 2007
Probes:
dielectrons :
sensitive probe of extended baryon structure medium modifications ?
meson in medium properties
Multistrange baryons: -(1321), 
,  mesons
Strategy:
Systematic measurements
in p +p, p+A and A+A at 2- 8 AGeV
RHIC, BES
Na61
experiment: chemical freeze-out
VDM
CBM
Fair
Begun et. al. arXiv:
HADES

4. Radiation from baryonic matter
Dense matter 2-40 ; baryon resonances + nucleons + (20-30%) pions
Vacumm
RNe+e- q
pion cloud e+ e- e- e+ e+ e- q q q - qq q e- e+ q qq - q q q
How does the radiation from such matter look like?

5. 33 (J=3/2)  N (J=1/2) M1 Transition
Time like region :
M. Pena, G. Ramahlo PRD85 (2012) ?
space like region:
„pion cloud”
I. G. Aznauryan and V. D. Burkert, Prog. Part. Nucl.
Phys. 67, 1 (2012) arXiv:
„quark core”
„dipole fit”
cloud/core ~ 0.44/0.56
large contributions (30% at Q2=0) of pion cloud
Dalitz decay: sensitivity to |GM |2 (q2) in time like region:
„QED”
Mee [GeV/c2]

6.  -meson in hot and dense matter
Data : Na60 acceptance corrected : EPJC 59 (2009) 607
calculations: Hess/Rapp: NPA806(2008)339.
„Baryonic loops ”
pion loop
direct  - N* /
Resonance decays !
 - /N* couplings play big role in „rho” melting observed in UrHIC
-> connection to Baryon Resonance Dalitz decays

7. e+e- from Baryon Resonances in vacuum
eTFF-em. Transition Form Factors
pp->ppe+e- @1.25 GeV
pp->ppe+e- @3.5 GeV
contribution fixed from 1 pion production
BR (Ne+e-)  4*10-5 agrees with model predictions.
G(q2 ) dependence not very essential at this low energy..
Resonances with Mass up to 2 GeV included
calculations with point-like RN* does not describe data
FF(q2 ) dependence very important -> Vector Meson contribution !

8. e+e- from nuclear matter* 
HADES: PRC84 (2011) e- 0
B=1
„excess”
: B= 1
: B= 1
VM: M>0.6
B = 0 0
excess VM
meson cocktail („freeze-out” component)

9. e+e- excess
SIS100?
Reference measurements for Au + Au collisions at FAIR pp vs 3.5 GeV
HADES PLB715 (2012) 304

10. Multistrange baryon production
data: HADES PRL 103 (2009)
AGeV
at SIS18 (1321) production significantly larger than transport model (UrQMD) and statistical model predictions
Excitation function of  , 
(also ) not known below sNN <7 GeV…
640 MeV below NN threshold !

11. Particle rates in Ar+KCl @ 1.75 AGeV
data: HADES:
EPJA 47 (2011) 21
SHM: S. Wheaton, J. Cleymans,
Comp. Phys. Comm. 180 (2009) 84
calculation with Thermus (SHM): strangeness: canonical ensamble with suppression induced via strangeness conservation colume (RC )
enhanced  (2),  (hidden strangeness)
enhanced  (~25)
overal 2/n.d.f ~2.3 !

12. HADES at SIS100: phase space coverage for e+e-
yCM
yCM
yCM
Ebeam = 1 GeV/u
overall acceptance for di- electron pairs Acc ≈ 35%
with nice mid-rapidity coverage
Ebeam = 8 GeV/u
Acc ≈ 20%
shift towards backward rapidity
Ebeam = 11 GeV/u
 Acc ≈ 20%

13.  mass dependence on beam energy
Simple model: pure BW  d/dm (~1/Mee 3)  exp(-M/T)
Higher beam energy enhance  pole region

14. Tracking detector occupancies
GeV/u equivalent to 8 AGeV and factor 2 lower than Au+Au 4 AGeV
Cell size is factor of 2 larger
tracking efficiency

15. PID capabilities at SIS100
RPC
4 AGeV
ToF
K/ ~1.2 GeV/c p/~1.8 GeV/c
K/ ~0.8 GeV/c p/~1.8 GeV/c

16. HADES : expected performance at SIS100
data !: 1.2 AGeV :
track density equivalent to 8 AGeV K-
hadron ID
K0s
First measurement at such low beam energy !
Lepton ID f

17. Count rate estimates, dilepton cocktails..
Au+ 4.0 GeV per 1 hour
K *106
K *105
K0s *104
  K+ K *104
  p
  
 e+e
CB rejection not yet optimimized
(no Ecal matching, close pair identification,..)

18. Summary
SIS100 opens new opportunities : larger beam energy, larger density compressed baryonic matter not studied before by means of penetrating
Results from SIS18 strongly motivate continuation of HADES physics programme at SIS100
HADES detector is in big part ready for new campaigns

19. Reaction plane reconstruction in FW
AGeV
Cut on the Q magnitude:
Q > 6
Q > 3
No cut

4 < b < 8
AGeV
Q > 6
Q > 3
No cut

5 < b < 10

20. Ecal for HADES electron ID:   reconstruction Ni+Ni @ 8 AGeV
8 AGeV
= 6% S/B = 2%
8 AGeV
= 6% S/B = 0.4%

21. HADES @ SIS100 : Phase space covaregeK-  K0
UrQMD:
4 mln events 4 AGeV

22. Kaonic Nuclear clusters
Stat. model predictions for cluster formation in Au-Au collisions
promising candidate ?: K- pp system
predictions from theory : 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, (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:   
R. Kotte : (p) source in ArKcl
but  no sensitivity to p potential and ..no signal in p inv. mass visible