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

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

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

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

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

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. C69 034910, C74 024904 Strong high pT suppression seen in RAA at RHIC and LHC energies. Phys.Rev. C77 034906 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

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 13 20 30 40 80 160 2012/14 2014 2015 2011 - 2012 2009/10/11 energy (A GeV) NA61 13 20 30 40 80 160 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

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

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. E17 1367 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

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

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

Detailed Ω- production measurement in Pb+Pb possible at NA61 experiment. EPJ C14 633 (WA97) Existing measurements: low statistics, only for 40A and 158A GeV, only low pT. NA61 can improve x10-100 in statistics, can add further collision energies, can extend pT reach. PRL 94 192301 (NA49) 29 June 2012 HIC Town Meeting

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

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

Pb+Pb collision at 80A GeV/c NA61 could record valuable Pb+Pb data: In NA61 E—A scan high statistics (x10-100 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

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 13 20 30 40 80 160 energy (A GeV) 29 June 2012 HIC Town Meeting

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 (2017-19). 29 June 2012 HIC Town Meeting

Backup slides 29 June 2012 HIC Town Meeting

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

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