Some thoughts about the IR-Design and Si-tracking E.C. AschenauerEIC Tracking R&D Meeting, March 20121

eSTAR ePHENIX Coherent e-cooler Newdetector 30 GeV Linac Linac 2.45 GeV 100 m GeV Beamdump Polarizede-gun 0.6 GeV E/Eo Eo Eo Eo Eo Eo Eo Eo Eo Eo Eo Eo Eo 0.02 Eo All energies scale proportionally by adding SRF cavities to the injector All magnets would installed from the day one and we would be cranking power supplies up as energy is increasing Staging of eRHIC: E o : 5 -> 30 GeV 2 E.C. AschenauerEIC Tracking R&D Meeting, March 2012

eRHIC high-luminosity IR with  *=5 cm E.C. AschenauerEIC Tracking R&D Meeting, March  10 mrad crossing angle and crab-crossing  High gradient (200 T/m) large aperture Nb 3 Sn focusing magnets  Arranged free-field electron pass through the hadron triplet magnets  Integration with the detector: efficient separation and registration of low angle collision products  Gentle bending of the electrons to avoid SR impact in the detector Proton beam lattice © D.Trbojevic, B.Parker, S. Tepikian, J. Beebe-Wang e p Nb 3 Sn 200 T/m G.Ambrosio et al., IPAC’10 eRHIC - Geometry high-lumi IR with β*=5 cm, l*=4.5 m and 10 mrad crossing angle  this is required for cm -2 s -1 Question to answer How does this design need to be adapted for eSTAR/ePHENIX? ATTENTION: eRHIC clock will be changing to 75ns

EIC Tracking R&D Meeting, March E.C. Aschenauer IR-Design All optimized for dedicated detector Have +/-4.5m for main-detector  roman pots / ZDC  low Q2-tagger need to be integrated in the IR design

Integration into Machine: IR-Design E.C. AschenauerEIC Tracking R&D Meeting, March space for low-  e-tagger Outgoing electron direction currently under detailed design  detect low Q 2 scattered leptons  want to use the vertical bend to separate very low-  e’ from beam-electrons  can make bend faster for outgoing beam  faster separation  for 0.1 o <  <1 o will add calorimetry after the main detector

Kinematics of Breakup Neutrons E.C. AschenauerEIC Tracking R&D Meeting, March Results from GEMINI++ for 50 GeV Au by Thomas Ullrich +/-5mrad acceptance seems sufficient Results: With an aperture of ±3 mrad we are in relative good shape enough “detection” power for t > GeV 2 enough “detection” power for t > GeV 2 below t ~ 0.02 GeV 2 we have to look into photon detection below t ~ 0.02 GeV 2 we have to look into photon detection ‣ Is it needed? Question: For some physics rejection power for incoherent is needed ~10 4 For some physics rejection power for incoherent is needed ~10 4  How efficient can the ZDCs be made?

Diffractive Physics: p’ kinematics 5x250 5x100 5x50 E.C. Aschenauer 7 EIC Tracking R&D Meeting, March 2012 t=(p 4 -p 2 ) 2 = 2[(m p in.m p out )-(E in E out - p z in p z out )]  “ Roman Pots” acceptance studies see later ? Diffraction: p’ Simulations by J.H Lee

proton distribution in y vs x at s=20 m 25x2505x50 E.C. Aschenauer 8 EIC Tracking R&D Meeting, March 2012 without quadrupole aperture limit 25x250 5x50 with quadrupole aperture limit

Accepted in“Roman Pot”(example) at s=20m 25x2505x50 E.C. Aschenauer 9 EIC Tracking R&D Meeting, March x2505x50 Generated Quad aperture limited RP (at 20m) accepted

Si-Vertex  Detector RD  Si-Vertex Detector  MAPS technology from IPHC concept as STAR-HFT, CBM, Alice, … Barrel: 4 double sided 4 double sided cm 10 sectors in  Rapidity coverage: at least +/- 1 chip 20mm x 30mm  1cm 300 pixel pitch 33 micron dual sided readout, one column 60  s readout time Radiation length 5 permill / layer (50  m Si)  < 5  m Vertex resolution Forward Disks: At least 4 single sided disks spaced in z starting from 20cm Radial extension 3 (19  m pixel) to 12 cm (75  m pixel), dual sided readout  300x200ns = readout time 60micros need a 0.3xm region at each side of the wedge for readout Radiation length 3 permill / layer will explore new technology of stitching E.C. Aschenauer EIC Tracking R&D Meeting, March cm 1.1cm  pi/8  pixel size 75  m  300 pixel  pixel size 19  m

Our Goals  What does the LDRD want to answer  quantify the chip behavior laser test stand at columbia test stand with sources / cosmic at BNL  testbeams, i.e. new more radiation hard mimosa chips  “build” prototype chips / wedge using stitching  answer integrations questions, i.e. is anything else than air cooling needed  answer many questions by MC what is the occupancy for the different layers in the barrel and in the forward direction what is the needed resolution of the TPC / Barrel Gem-tracker to track from inside out what intermediate detector is needed if we have to track outside in synchrotron radiation load do we have heavy fragments in the direction of the disks vertex finding efficiency depending on pt-cut off E.C. Aschenauer EIC Tracking R&D Meeting, March

What was done till now  Laser teststand at columbia working  first results on Si-chips available  start to establish Si-pixel collaboration with STAR, CBM, IPHC  offer made to postdoc to work on this  STAR will install test pixel detector this summer  will most likely get involved in this E.C. Aschenauer EIC Tracking R&D Meeting, March

Simulation well ahead E.C. AschenauerEIC Tracking R&D Meeting, March Pythia-event

Symmetric version with improved detector model 14 All FairRoot simulations done by Yulia Zoulkarneev FairRoot has also a fast smearing generator, which is based on the actual material budget E.C. AschenauerEIC Tracking R&D Meeting, March 2012

ExperimentCentral FieldLengthInner Diameter ZEUS1.8 T2.8 m0.86 m H11.15T3.6 m1.6 m BABAR1.5T3.46 m1.4 m BELLE1.5T3.0 m1.7 m GlueX2.0T3.5 m1.85 m ATLAS2.0T5.3 m2.44 m CMS4.0T13.0 m5.9 m PANDA (*design) 2.0T4.9m1.9 m CLAS12 (*design) 5.0T1.19 m0.96 m Magnetic Field Considerations E.C. Aschenauer 15 EIC Tracking R&D Meeting, March 2012 Solenoid Fields – Overview: Suggest 4-5m long Solenoid with diameter ~3m and B-Field of ~3T particles with very small scattering angle need to be treated separately

“Easier” Solenoid Field – 2T vs. 4T? Intrinsic contribution ~ 1/BIntrinsic contribution ~ 1/B Multiple scattering contribution ~ 1/BMultiple scattering contribution ~ 1/B p = 50 GeV p = 5 GeV B=2T B=4T E.C. Aschenauer 16 EIC Tracking R&D Meeting, March 2012

Multiple scattering contribution p = 50 GeV p = 5 GeV Multiple scattering contribution dominant at small angles (due to B T term in denominator) and small momenta E.C. Aschenauer 17 EIC Tracking R&D Meeting, March 2012

 p/p angular dependence Can improve resolution at forward angles by offsetting IP p = 50 GeV p = 5 GeV E.C. Aschenauer 18 EIC Tracking R&D Meeting, March 2012

Solenoid and Dipole field p = 50 GeV p = 5 GeV As expected, substantially improves resolutions at small angles E.C. Aschenauer 19 EIC Tracking R&D Meeting, March 2012

E.C. AschenauerEIC Tracking R&D Meeting, March BACKUP

Multiple scattering contribution: Intrinsic contribution (first term): B=central field (T) B=central field (T) σ rφ =position resolution (m) σ rφ =position resolution (m) L’=length of transverse path through field (m) L’=length of transverse path through field (m) N=number of measurements N=number of measurements z = charge of particle z = charge of particle L = total track length through detector (m) L = total track length through detector (m) γ= angle of incidence w.r.t. normal of detector plane γ= angle of incidence w.r.t. normal of detector plane n r.l. = number of radiation lengths in detector n r.l. = number of radiation lengths in detector msc intr Assumptions: circular detectors around interaction point circular detectors around interaction point n r.l. = 0.03 (from Hall D CDC) n r.l. = 0.03 (from Hall D CDC) Magnetic Field: Super simple resolution estimates E.C. Aschenauer 21 EIC Tracking R&D Meeting, March 2012

What needs to be covered E.C. AschenauerEIC Tracking R&D Meeting, March e’t (Q 2 ) e L*L*L*L* x+ξ x-ξ H, H, E, E (x,ξ,t) ~ ~  J  p p’ Inclusive Reactions:  Momentum/energy and angular resolution of e’ critical  Very good electron id  Moderate luminosity >10 32 cm -1 s -1  Need low x ~10 -4  high √s (Saturation and spin physics) Semi-inclusive Reactions:  Excellent particle ID ,K,p separation over a wide range in   full  -coverage around  *  Excellent vertex resolution  Charm, bottom identification  high luminosity >10 33 cm -1 s -1 (5d binning (x,Q 2,z, p t,  ))  Need low x ~10 -4  high √s Exclusive Reactions:  Exclusivity  high rapidity coverage  rapidity gap events  high resolution in t  Roman pots  high luminosity >10 33 cm -1 s -1 (4d binning (x,Q 2,t,  ))