9/10/ E.Kistenev, BNL PHENIX in the next decade Erice, September 17, 2012 Slides contributed by J.Nagle, W.Zajc, D.Morrison, D.Karzeev, V.Pantuev

2002: discovery of high p T suppression at RHIC D.Karzeev, 2004 RHIC II and dedicated program at RHICII are necessary to extend our understanding of collective QCD phenomena discovered at RHIC Suppression of hadrons with large transverse momentum in central Au+Au collisions at √s NN = 130 GeV, PHENIX Collaboration (K. Adcox et al.), Phys.Rev.Lett.88:022301,2002K. Adcox et al.Phys.Rev.Lett.88:022301, citations

Since 2002 the goal was to confirm that the observed high p T suppression is indeed due to the parton energy loss in the media: - Search for fluctuations –> transport coefficients; - Energy scan -> search for critical point; - Studies of the suppression dependence on the quark mass; - Studies of the suppression dependence on collision energy (RHIC vs LHC); CMS, PbPb, Isolated photons, 2.76 TeV

Systematic investigation of variations with  s TeV at LHC very similar to 200 GeV at RHIC!

l Challenge: Solving a multi-scale, highly dynamic transport problem in an intrinsically quantum system. l Rewards:  Possible resolution of quasiparticles  Measurement of shear viscosity to entropy ratio  /s  Measurement of transport coefficients in a fundamental gauge theory The Intellectual Challenges and Rewards W.Zajk, Tribble com. talk

6 Mapping Out Media Coupling with Jet Probes Key is independently measuring both sides of this equation! Scenario #1 (x10) reveals peak in q ! ^ QCD Weak Case RHIC Perfect Fluid A. Majumder, B. Muller, X.N. Wang, PRL (2007). “Small Shear Viscosity Implies Strong Jet Quenching” Liao and Shuryak, PRL (2009) “Jet Quenching is a few times stronger near T c relative to the QGP at T > T c.” In a weakly coupled turbulent plasma

Range of estimates:  (Compilation by A. Tang, R.J. Lacey) Estimated “error band” Indirect “bounding”  /s at RHIC PHENIX, PRL (2010) “Large v 2 is striking in that it exceeds expectations of pQCD models even at 10 GeV/c” J.Liao arXiv: v1 [nucl-th] 5 Sep 2012 “AdS/CFT-motivated model with cubic path-length which enhances the late time quenching that mimics the near-Tc enhancement describes v2 at high pt for RHIC”

Jet or photon Jet/photon tagging for q measurements

9 Fractional momentum loss Measure fractional momentum loss (dp T /p T ) instead of R AA Different dp T /p T for same R AA pTpT LHC RHIC  p T /p T RHIC and LHC give a key lever arm in temperature R AA arXiv: Horowitz and Gyulassy, NPA (2011) “The surprisingly transparent sQGP at the LHC [compared to RHIC]” Analogy: e - energy loss in electrical field

Can RHIC precisely measure key observables Rates are huge. They will allow differential measurements with varying collision geometry (v 2, v 3, A+B, U+U, …) & precision control measurements (d+Au and p+p) !! Au+Au (central 20%) p+pd+Au >20GeV 10 7 jets 10 4 photons 10 6 jets 10 3 photons 10 7 jets 10 4 photons >30GeV 10 6 jets 10 3 photons 10 5 jets 10 2 photons 10 6 jets 10 3 photons >40GeV10 5 jets10 4 jets10 5 jets >50GeV10 4 jets10 3 jets10 4 jets Based on full stochastic cooling, no additional accelerator upgrades

Further Leveling the playing field with LHC Use advantages of RHIC (machine is dedicated to HI physics); Vary the species (shape, isotopic content); Study threshold behavior varying collision energy; Do better measurements LHC comparable or increased coverage; comparable or better resolution; better hermeticity, uniformity

ambitious upgrade to study the sQGP with a new compact, hermetic, large acceptance and high rate calorimetry based detector High statistics Upsilons, large Dijet and  -jet rates with full calorimetry, photon/charm/beauty tagging of jets with PreShower/VTX, low-x jet, , quarkonia, transverse spin probes, staged into ePHENIX detector. sPHENIX Decadal Plan

Specs for NEW sPHENIX Central Detector 13 9/10/2015

sPHENIX MIE Project ( major item of equipment ) 14 9/10/2015 Magnet Solenoid 2 Tesla, R inner = 70 cm Accordion Tungsten-Fiber EMCal Fe-Scintillator HCal Also acts as flux return for magnetic field

15 9/10/ GeV 19GeV 15GeV 6GeV 16GeV truth jets reconstructed jets GeV reconstructed Jets are dominated by real jets (known from HIJING truth) Full HIJING Event Analysis Very good jet finding efficiency even in the most central Au+Au events for E T > 20 GeV Jet Transverse Energy (GeV)

sPHENIX Electromagnetic Calorimeter 16 9/10/2015

sPHENIX Hadron Calorimeter Response ~ 75%/√E Tilt tuneup (mip’s)

First look on HC performance 18

Summary Heavy Ion Collisions produced major discoveries in “Physics in Collisions” in the last 10 years, jet quenching and unexpectedly strong elliptic flow are two examples. In the era of LHC RHIC still offers unique opportunities for detailed studies of matter phase transition on a phase boundary close to critical temperature. We need the lever arm of RHIC and LHC together to find a fundamental explanation for how the perfect fluid emerges at strong coupling near T c from an asymptotically free theory of quarks and gluons. Calorimetry based upgrade to PHENIX will create a tool to explore this opportunity with jets and direct photons being event observables and event tags of choice.