1 EIC EW Meeting, W&M, VA, May 2010 E.C. Aschenauer

Physics Topics E.C. Aschenauer EIC EW Meeting, W&M, VA, May  unpolarised and polarised inclusive physics  detect only the scattered lepton  F 2 and F L for proton and nuclei, g 1 and g 2 for proton / He-3 antishadowing “sweet” spot R=1 shadowing LHC  =0 RHIC  =3 Assumptions:  10GeV x 100GeV/n  √s=63GeV  Ldt = 4/A fb -1  equiv to cm -2 s -1  T=4weeks; DC:50%  Detector: 100% efficient  Q 2 up to kin. limit sx  Statistical errors only  Note: L~1/A  smearing effects can be significant

Physics Topics  unpolarised and polarised inclusive physics  detect only the scattered lepton  F 2 and F L for proton and nuclei, g 1 and g 2 for proton / He-3 EIC EW Meeting, W&M, VA, May Lets get a feeling for systematic uncertainties:  1% energy-to-energy normalization  low detector smearing will be crucial  tracking vs. calorimetry 1 - 2% vs % F L for fixed electron energy (4GeV) and proton energies: 50, 70, 100, 250 GeV Luminosity: 4fb -1 each setting E.C. Aschenauer

Physics Topics  unpolarised and polarised inclusive physics  detect only the scattered lepton  F 2 and F L for proton and nuclei, g 1 and g 2 for proton / He-3 EIC EW Meeting, W&M, VA, May Integrated Lumi: 5fb -1 Same issues with detector resolution as F 2 and F L in addition need to reduce systematics due to polarisation E.C. Aschenauer

Kinematics EIC EW Meeting, W&M, VA, May x Q2Q2  higher hadron energy at the same lepton beam energy allows access to lower x  higher lepton beam energy at the same hadron beam energy allows access to lower x E.C. Aschenauer

e’ Kinematics  Lets concentrate on 4GeV lepton energy  electron beam “replaces” yellow hadron beam EIC EW Meeting, W&M, VA, May Proton Energy 50 GeV 100 GeV 250 GeV 4x50 p e : 0-1 GeV p e : 1-2 GeV p e : 2-3 GeV p e : 3-4 GeV e- p/A 180 o 0 o No dependence on hadron beam energy Q 2 >0.1GeV 2 4GeV  >5 o 10GeV  >2 o 20GeV  >1 o E.C. Aschenauer

Hadron Kinematics EIC EW Meeting, W&M, VA, May x100 4x250 4x100 4x50 E.C. Aschenauer

Diffractive Physics: p’ kinematics EIC EW Meeting, W&M, VA, May x 100 t=(p 4 -p 2 ) 2 = 2[(m p in.m p out )-(E in E out - p z in p z out )] 4 x 50 4 x 250 ? Diffraction: E.C. Aschenauer

EIC EW Meeting, W&M, VA, May Current PHENIX Detector at RHIC MPC 3.1 < |  | < o <  < 5.2 o Muon Arms 1.2 < |  | < 2.4 South: 12 o <  < 37 o North: 10 o <  < 37 o Central Arms |  | < o <  < 110 o e- electrons will not make it to the south muon arm  to much material E.C. Aschenauer

What will the current PheniX see EIC EW Meeting, W&M, VA, May x100 p e : 0-1 GeV p e : 1-2 GeV p e : 2-3 GeV p e : 3-4 GeV 4x100 Current PheniX detector not really useable for DIS acceptance not matched to DIS kinematics E.C. Aschenauer

HCAL EM CAL Preshower The new PheniX Spectrometer  Coverage in |  | =< 4 (2 o <  < 30 o ) 0.1 < Q 2 < 100 (5 o – 175 o )  need an open geometry detector  planes for next decadal plan  replace current central detector with a new one covering |  | =< 1 EIC EW Meeting, W&M, VA, May cm 2T Solenoid EMCAL HCAL Silicon Tracker VTX + 1 layer Silicon Tracker FVTX 1.2 <  < o <  < 37 o North Muon Arm 68cm IP 80cm 145cm 5 2m 17.4 cm  y E.C. Aschenauer

IR-Design E.C. AschenauerEIC EW Meeting, W&M, VA, May m Q5 D5 Q4 90 m 10 mrad m 3.67 mrad 60 m m 18.8 m 16.8 m 6.33 mrad 4 m © D.Trbojevic 30 GeV e GeV p Or 125 GeV/u ions eRHIC - Geometry high-lumi IR with β*=5 cm, l*=4.5 m and 10 mrad crossing angle m

What can new PheniX do  PROs:  large coverage for scattered lepton  can do inclusive ep/eA physics through all stages of eRHIC  can do semi-inclusive and exclusive physics, which needs muon and electron-id (i.e. J/psi)  CONs:  momentum and angular resolution critical for precision inclusive physics  material budget in central detector is on the high side  IPs are better offset to the center of the detector for asymmetric colliders  very difficult because of symmetric design of central detector  NO PID and Muon-arm on forward direction  most of semi- inclusive and exclusive/diffractive physics not possible  High Luminosity IR design does not work with old and new PheniX  need to move focusing quads  lower luminosity  Remarks / Questions:  need to integrate 10mrad bend in design  need to integrate a luminosity measurement E.C. Aschenauer EIC EW Meeting, W&M, VA, May Summary: the new PheniX detector can make important measurements in ep/eA Lets integrate it into the design and the next decadal plan