1. NA61/SHINE: status and energy scans with Pb+Pb collisions
András László (for the NA61/SHINE Collaboration)
29 June 2012
HIC Town Meeting

2. Outline NA61/SHINE experiment HI physics with NA61/SHINE
Possible future physics at NA61
NA61 data taking programme with possible extension
Summary
29 June 2012
HIC Town Meeting

3. NA61/SHINE experiment
NA61 is a large acceptance hadron spectrometer experiment at the CERN SPS.
Main physics goals are to measure:
Hadronic spectra and fluctuactions in A+A for studying Onset of Deconfinement and searching for Critical Point in strong interactions, intermediate pT physics in p+p, p+A, A+A
Reference hadron spectra in p+C for T2K experiment
Reference hadron spectra in π-+C for the Pierre Auger Obs.
29 June 2012
HIC Town Meeting

4. HI physics with NA61/SHINE
Change of energy dependence of hadronic observables around SPS energies in A+A.
Compatible explanation: constant temperature and pressure in mixed phase.
(Onset of deconfinement)
Compatible explanation: decrease of strangeness carrier masses, decrease of number of strange to non-strange degrees of freedom.
29 June 2012
HIC Town Meeting

5. Searching for the Critical Point of strongly interacting matter in A+A collisions.
In case of freeze-out close to critical point with large enough system: larger fluctuations, power-law like behavior => hill of fluctuations expected in E—A plane.
Lattice QCD indicates existence of a critical point of strongly interacting matter at freeze-out termperatures forseen to be accessible around SPS energies.
Pb+Pb
Be+Be 13
NA61 is searching for CP and is studying OoD by performing an E—A scan program with moderate statistics.
29 June 2012
HIC Town Meeting

6. Medium effects in A+A: energy dependence of RAA (nucl. mod. fact.)
Strong intermediate / high pT hadron suppression seen at RHIC and LHC energies
Strong energy dependence of this effect toward SPS energies is expected
Phys.Rev. C , C
Strong high pT suppression seen in RAA at RHIC and LHC energies.
Phys.Rev. C
NA49 measured RAA at SPS energies but not to sufficiently high pT. NA49 measured RCP and sees some suppression.
NA61 is completing RAA measurements by the high statistics p+p and p+Pb data.
29 June 2012
HIC Town Meeting

7. The HI physics program previously completed by the NA49 experiment.
NA61 is performing its HI physics study with the below data taking programme.
p+p
Be+Be
Ar+Ca
Xe+La
p+Pb
2012/14
2014
2015
2011 -
2012
2009/10/11
energy (A GeV)
NA61
Pb+Pb
p+p
C+C
Si+Si
energy (A GeV)
NA49 (1996 -
2002)
p+Pb
The HI physics program previously completed by the NA49 experiment.
Colliding system and energy scan program of NA61 and its present status.
29 June 2012
HIC Town Meeting

8. Possible future physics with NA61
Measurement of open charm production in A+A in this interesting energy region.
Precise measurements on production of multi-strange particles in A+A.
Extension of pT reach of particle spectra in A+A.
Completing existing energy scan data in A+A for the largest colliding systems.
29 June 2012
HIC Town Meeting

9. Preferred decay channel: D0 → K- + π+ channel (BR=3.87%)
No detailed measurement of open charm production in A+A is available around SPS energies.
Int.J.Mod.Phys. E
Open charm production measurement possible at NA61 experiment. With 50M 160AGeV Pb+Pb(0-5)%: 5M D0 expected.
Preferred decay channel:
D0 → K- + π+ channel (BR=3.87%)
D0+D0
29 June 2012
HIC Town Meeting

10. D0 meson detection in NA61: standard setup + vertex detector.
VTPC1
VD3
VD2
VD1
target
29 June 2012
HIC Town Meeting

11. Extrapolation of the simulated results to 50 M events :
D0 meson detection in NA61 possible with a 10μm resolution vertex detector.
Simulation for 100k central Pb+Pb collisions at 158 AGeV (by Pawel Staszel, Yasir Ali)
Extrapolation of the simulated results to 50 M events :
i) measurement of about 40k D0 + D0 mesons
ii) S/B=3.1, signal significance (SNR) = 350
29 June 2012
HIC Town Meeting

12. Detailed Ω- production measurement in Pb+Pb possible at NA61 experiment.
EPJ C (WA97)
Existing measurements: low statistics, only for 40A and 158A GeV, only low pT.
NA61 can improve x in statistics, can add further collision energies, can extend pT reach.
PRL (NA49)
29 June 2012
HIC Town Meeting

13. Extension of intermediate pT charged pion spectra in Pb+Pb at SPS energies.
Charged pion pT spectra at midrapidity has been measured by NA49 up to 4.5GeV/c transverse momentum.
Can be potentially extended by NA61 experiment up to about 5.5-6GeV/c, which is close to the phase space boundary.
For protons, even up to 6.5-7GeV/c pT reach possible due to flatter slope.
29 June 2012
HIC Town Meeting

14. Completion of existing energy scan data in A+A for the largest colliding systems:
NA49 published results on basic hadron production properties in central Pb+Pb at 20A, 30A, 40A, 80A, 158A GeV based on moderate statistics of 400k events per reaction. These data are excellent basic reference for NA61 results.
Minimum bias data were only recorded for 40A, 158A GeV. 13A GeV was not recorded at all.
STAR recorded high stat Au+Au collisions at several energies in the SPS range down to 30A GeV.
No 13A, 20A GeV data. Narrow y acceptance, low pT cut, no unbiased centrality selection.
29 June 2012
HIC Town Meeting

15. Pb+Pb collision at 80A GeV/c
NA61 could record valuable Pb+Pb data:
In NA61 E—A scan high statistics (x NA49) and high resolution detectors (PSD, He-beampipe) are used.
Simultanous multiple prescalable triggers (T1-T4), calibration (dE/dx), analysis methods (identity) were developed for NA61. These should significantly decrease systematic errors.
New observables proposed to increase sensitivity to OoD and CP (strongly intensive quantities).
Upgrade by a high resolution vertex detector should allow for high statistics measurements of open charm production.
Pb+Pb collision at 80A GeV/c
NA61/SHINE 2011
29 June 2012
HIC Town Meeting

16. NA61 data taking programme with possible extension
The NA61 HI physics study is in progress with the below data taking programme.
2019
2018
2017
Possible extension with Pb+Pb energy scans.
and its possible extension
Pb+Pb
2016
Xe+La
2015
Ar+Ca
2014
Be+Be
2011 -
2012
p+Pb
2012/14
p+p
2009/10/11
energy (A GeV)
29 June 2012
HIC Town Meeting

17. Summary
NA61 is a uniqe hadron spectrometer facility to study strongly interacting matter in the region of onset of deconfinement and close to the critical point (fixed-target SPS energies).
NA61 proposes extension of its accepted physics program with the following points:
Detailed Pb+Pb energy scan with existing NA61 detector (2016).
Large statistics Pb+Pb data taking at 3 energies with NA61 + new vertex detector ( ).
29 June 2012
HIC Town Meeting

18. Backup slides
29 June 2012
HIC Town Meeting

19. Phase space of the measured D0 mesons (100k central Pb+Pb collisions at 158 AGeV)
29 June 2012
HIC Town Meeting

20. Global plans for data taking on high energy nucleus-nucleus collisions:
2012
2013
2014
2015
2016
2017
2018
2019
LHC:
Alice,Atlas,CMS
LS1
LS2
data taking
experiments
SPS:
NA61/SHINE ?
RHIC:
STAR,PHENIX ?
eRHIC?
NICA:
MPD ? ?
in plans
SIS-100:
HADES, CBM ?
In near future NA61/SHINE may remain
the only large acceptance hadron
spectrometer at the non-LHC energies
29 June 2012
HIC Town Meeting