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Beam Energy Scan Results. Ron Soltz for PHENIX. Baryon Chemical Potential B (GeV). BES Motivation = CEP. LQCD EoS and behavior of chiral susceptibility. Limited theoretical guidance, need data. ?. Chiral effective models. PHENIX Data and Measurements. QM12 p 0 suppression
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Beam Energy Scan Results Ron Soltz for PHENIX R. Soltz for PHENIX - Quark Matter 2014
Baryon Chemical Potential B (GeV) BES Motivation = CEP LQCD EoS and behavior of chiral susceptibility • Limited theoretical guidance, need data ? Chiral effective models R. Soltz for PHENIX - Quark Matter 2014
PHENIX Data and Measurements • QM12 • p0 suppression • PRL.109.152301 • J/psi • PRC.86.064901 • Flow, Fluctuations • This talk • Multiplicity • HBT Radii • Fluctuations R. Soltz for PHENIX - Quark Matter 2014
Multiplicity (quark) scaling 10.1103/PhysRevC.89.044905 Participant quark scaling works well √sNN= 62-200 GeV R. Soltz for PHENIX - Quark Matter 2014
Nucleon Scaling see poster B-10 by Jeff Mitchel Participant nucleon scaling works well √sNN<= 27 GeV Implications for CEP and associated signatures? R. Soltz for PHENIX - Quark Matter 2014
HBT BES Results see poster I-02 by Alex Mwai • 3D Gaussian fits • Bertsch-Pratt coord. • LCMS (p1z+p2z=0) • Coulomb Corrected R. Soltz for PHENIX - Quark Matter 2014
Ye OldeHBT formulae • Formerly used to understand dynamics before era of multi-stage models, assumptions too restrictive Chapman, Scotto, Heinz, PRL.74.4400 (95) empirical fit just as effective Makhlin, Sinyukov, ZPC.39.69 (88) (R2out-R2side) sensitive to emission duration Anticipate extended emission duration with 1st order transition R. Soltz for PHENIX - Quark Matter 2014
mT scaling Rlong Rout Rside • PHENIX and STAR consistent arxiv:1403.4972 • all radii linear • Ri=a+b/√mT • Used to interpolate to common mT R. Soltz for PHENIX - Quark Matter 2014
Geometric Scaling All radii linear in R, all slopes linear in 1/√mT For 0-5% central R = σx/√2 = σy/√2 R. Soltz for PHENIX - Quark Matter 2014
HBT radii vs. √sNN • PHENIX,STAR,ALICE data • mT=0.26 GeV interpolations • Rlong decreasing with √sNN • Rout,Rlong curvature differ from Rside • construct ratios and differences R. Soltz for PHENIX - Quark Matter 2014
Measures of emission duration • Non-monotonicity in Rout/Rside • Subtract √2R to (over) estimate expansion R. Soltz for PHENIX - Quark Matter 2014
Emission duration and expansion/lifetime • Non-monotonicity magnified with (Rout)2 – (Rside)2 • Rside/Rlong indicative of expansion/lifetime R. Soltz for PHENIX - Quark Matter 2014
Fluctuations in (s)PHENIX • Sensitive to correlation length, ξ [LQCD] Variance : 2 = <(N)2> ~ 2 [x(2)/x(1)] Skewness: S= <(N)3>/2~ 5.5 [x(3)/x(2)] Kurtosis: K2= <(N)4>/2-32~ 9 [x(4)/x(2)] • Quark susc., x, LQCD calculate directly (μ=0) • for μ>0, higher order terms needed • sPHENIX in 2019 (timing is of the essence) strong interest in BES-2 physics large acceptance detectors: VTX, Si, TPC R. Soltz for PHENIX - Quark Matter 2014
BES2 sPHENIX (wishful) projections http://www.phenix.bnl.gov/plans.html - BES2 Whitepaper PRL.105.022302 R. Soltz for PHENIX - Quark Matter 2014
Summary Conclusions • Nucleon Scaling below 27 GeV • implications for other CEP signatures ?! • Non-monotonic behavior in Rout:Rside ratios and differences, Rside:Rlong (expansion/lifetime) • if location at softest EoS, peak height holds key to transition order • consider change to nucleon dominated freeze-out • multi-stage modeling needed for HBT • sPHENIX has strong interest in BES-2 physics R. Soltz for PHENIX - Quark Matter 2014
Backup • Starts here. R. Soltz for PHENIX - Quark Matter 2014
STAR Results R. Soltz for PHENIX - Quark Matter 2014
HBT radii vs. √sNN • STAR arxiv:1403.4972 • evidence for 1st order behavior not readily apparent • construct ratios and differences • interpolate to common mT R. Soltz for PHENIX - Quark Matter 2014
mT = 0.19 GeV R. Soltz for PHENIX - Quark Matter 2014
mT = 0.19 GeV R. Soltz for PHENIX - Quark Matter 2014
mT = 0.33 GeV R. Soltz for PHENIX - Quark Matter 2014
mT = 0.33 GeV R. Soltz for PHENIX - Quark Matter 2014
Net ChargeDistributions Net-charge (Nq = N+ - N- ) Net-charge (Nq = N+ - N- ) • Correlation length related to moments of conserved quantities including net charge • Correlation length should diverge at the critical point in the phase diagram R. Soltz for PHENIX - Quark Matter 2014
Net Charge Moments They scale as correlation length R. Soltz for PHENIX - Quark Matter 2014
UrQMD √sNN Dependence of Net Charge Fluctuations • Neither K nor S vary with centrality at 7.7, 39, 62.4 and 200 GeV • Kurtosis vs energy is flat within errors • Skewness tracks UrQMD prediction • Analysis of data sets from √s = 19.6, 27 GeV still to be completed R. Soltz for PHENIX - Quark Matter 2014