1. PHENIX results and prospects regarding strangeness and charm David Morrison (Brookhaven National Laboratory) for the PHENIX Collaboration

2. David Morrison s, c, b select strangeness results from first year PHENIX data single electrons, electron pairs from first year PHENIX data showing capabilities for heavy quark measurement expectations for heavy quarks in current run mass

3. David Morrison Acceptance as it will be when PHENIX is fully installed and instrumented PHENIX in its first year

4. David Morrison FeNIX

6. David Morrison First year data set energy  s NN = 130 GeV 5M minimum bias triggers recorded –essentially all data from final 3 weeks of run –simple vertex location and other quality cuts yield 1.6M useful events global observables, hadron spectra, HBT, lepton(s),...

7. David Morrison 0-5% 5-10% 10-15% 15-20% 20-25% 25-30% Normalized BBC energy Normalized ZDC energy 5  60%3.7  60% 80-92% 19  60% 60-80% 76  15%123  15% 30-60% 178  15%383  15% 15-30% 271  15%673  15% 5-15% 347  15%945  15% 0-5% ParticipantsCollisionsCentrality Centrality determination

8. David Morrison Particle identification In first year analyses TOF resolution 120ps. Allows  K separation to ~1.6 GeV/c. For coming analyses, TOF resolution improved to ~96ps. Allows  K separation to better than 2.3 GeV/c.

9. David Morrison p T spectra Julia Velkovska QM01

10. David Morrison  p T  versus centrality

11. David Morrison Inverse slope systematics

12. David Morrison HIJING Comparison of inverse slopes Hijing shows weaker dependence on mass and centrality than seen in data. No surprise here: some aspects of data are better described by prescription including copious reinteraction. The limit in that regard is to look to a hydrodynamic model. Hijing with default parameters

13. David Morrison Hydrodynamic parameterization 1/m t dN/dm t = A  f(  )  d  m T K 1 ( m T /T fo cosh  ) I 0 ( p T /T fo sinh  ) to minimize contributions from hard processes fit m t -m 0 <1 GeV freeze-out temperature T fo surface velocity  t linear velocity profile  t (  ) =  t  surf. velocity  t = 2/3  t boost  (  ) = atanh(  t (  ) ) This is the usual result when integrating Boltzmann over large rapidity  range. With assumption of hyperbolic Bjorken-like freeze-out surface, same result holds for differential yield.

14. David Morrison PHENIX Preliminary 5% most central T fo ~ 104  21 MeV  t ~ 0.7  0.1 ~ 0.5  0.1 Systematic errors: ~8% in T fo ~5% in  t Arrows indicate upper p t in fit PHENIX Preliminary thesis work of Jane Burward-Hoy

15. T fo ~ 125 - 83 MeV ~ 104 MeV  t ~ 0.6 - 0.8 ~ 0.7 ~ 0.4 - 0.6 ~ 0.5 CERN Pb-Pb NA49: T ~ 132 - 108 MeV ~ 120 MeV  t ~ 0.43 - 0.67 ~ 0.55  2 contour overlap Systematic error estimate: ~8% T fo, ~5%  t

16. David Morrison K  /K  ratio at mid-rapidity PHENIX Preliminary K  /K  = 1.08  0.03(stat.)  0.22(sys.)  p/p = 0.64  0.01(stat.)  0.07(sys.) consistent across RHIC experiments

17. David Morrison K  /K + versus participants Weak (or no) dependence on centrality. Major contribution to systematic error is from uncertain decay, acc. corrections. Much improved in current analyses. PHENIX Preliminary Ratio of total yields at AGS energies (E866) also centrality independent Phys. Rev. C 60, 044904 (1999)

18. David Morrison C+C Ni+Ni KaoS E866/E917 Au+Au Si+Au S+S K  /K  NA44 Pb+Pb  s [GeV] K  /K + versus  s near-net baryon free regime associated production of K + off existing baryons and baryon resonances is a large contribution at lower energies PHENIX Preliminary

19. David Morrison K/  versus participants measurements at mid- rapidity rises from values for p+p at  s = 63 GeV at p T = 0.8 GeV/c –Alper et al, NP B87(1975) –K  /   = 0.10, K  /   = 0.14 PHENIX Preliminary

20. K + /  + versus p T PHENIX preliminary NA44 Pb+Pb pT [GeV/c] p+p  s = 20GeV E866 Au+Au K+/+K+/+ p+p  s = 25 GeV ratio rises with p T, as at AGS, SPS low p T pions drive down ratio not enough p T reach in current result to observe trend as in p+p

21. David Morrison further p T dependence X. N. Wang, Phys. Rev C58, 2321 (1998)nucl-ex/0109003, submitted to PRL

22. David Morrison quarks and gluons in medium particles w/o valence quarks mainly by gluon mediated production K, p separation from  from about 6 to 15 GeV/c using RICH (K  +  p)/(K  +  p) sees gluon-quark difference in energy loss possible with 2001 data –high p T 2 nd level trigger to enhance signal pTpT 615 range of possible measurement ?

23. high pT electrons and heavy quarks in p+p at RHIC energies, the signal (from c-quark decay) is expected to be about e/  ~ 3-4x10  4 in Au+Au collisions at RHIC e/  may be as high as 10  3, given the observed suppression of high pT hadrons. charm is principal source around p T = 1-2 GeV/c; b- decay becomes main source above p T = 3-4 GeV/c  e from  0 Dalitz e from c decay e from b decay Y. Akiba, QM’95

24. single electrons Y. Akiba (QM01) RICH and EMCal together with tracking in central arms are used to identify electrons with the statistics from year 200 run, it has been possible to measure the electron spectrum up to 4 GeV/c very detailed subtraction of conversion electrons required in order to obtain useful signal D 0 K -  + D 0 K - e + e D 0 K -  + 

25. electron pairs Y. Akiba (QM’01) extends to J/  region statistics obtained from  s NN = 130 GeV too limited to measure J/  backgrounds small enough that successful measurement in current run looks certain

26. prospects for current run lvl2 trigger tailors event mix 300  b  Au+Au at  s NN = 200 GeV should provide –60M minimum bias events –30K J/    +  - in muon arm –6K J/   e + e - in central arm –15K (charm) e’s with p T > 2 GeV/c (central 10%) p-p comparison data: –same probes as in Au-Au with roughly half the statistical precision from PHENIX design documents

27. was thenis now

28. David Morrison strange so far, charm coming in the moderate p T part of phase space measured so far, K- yields very closely track K+ yields –can test this trend to much higher p T in current run (TOF, RICH) consistency with significant reinteraction, approach to statistical equilibrium –!Hijing slopes, hydro. for singles, rise in  p T , radial and elliptic flow drives interest in more sensitive tests of strangeness production... –multi-strange particles, HBT, balance functions... and in production of heavier quarks –single electron and electron pair measurements demonstrate ability –newly installed muon arm –open charm, J/ 

29. David Morrison

30.  2 contours of  -K-p PHENIX Preliminary 1 2 3  2 /NDF 1 10 2 10

31. K  /K  versus p T weak (or no) dependence on p T within errors differential K- yields track those of K+ throughout phase space

32. pA as baseline for strangeness Participant Scaling N coll E910 preliminary PHENIX Preliminary

33. chemical freeze-out PHENIX preliminary hep-ph/0002267: F.Becattini, et al.

34. Corrections to the Raw Spectra Used MC single particles and track embedding to correct for Tracking inefficiencies and momentum resolution Geometrical acceptance Decays in flight (  ’s and K’s) Correction is p and PID dependent Particle Acceptance 0.2 GeV/c -0.35 <  < 0.35

35. David Morrison m T spectra