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This document discusses the critical detector requirements for inclusive, semi-inclusive, and exclusive reactions in high-energy physics experiments. It highlights the energy variability, large acceptance, and particle identification needed for electron, proton, and other particles across a wide momentum range. The text delves into the importance of excellent secondary vertex resolution, systematic uncertainty reduction, and tagging in exclusive and diffractive reactions. Energy simulations and luminosity numbers for MeRHIC and eRHIC systems are also presented, along with momentum, scattering angles, and momentum vs. angle correlations for various particles. Moreover, ideas for detector concepts, IR design considerations, and detector simulations using Geant-3 are discussed in detail. The text emphasizes the significance of specific detector components, such as solenoids, dipoles, and various tracking and calorimetry technologies, for precise measurements and triggering in high-energy physics experiments. It also outlines backup plans and designs, as well as comparisons between different particle collision facilities like Zeus at HERA I and II, and discusses the challenges and solutions in detector and IR layouts for upcoming experiments.
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Some thoughts to stimulateDiscussion EICC @ Stony Brook, January 2010
Detector Requirements from Physics EICC @ Stony Brook, January 2010 • ep-physics • the same detector needs to cover inclusive (ep -> e’X), semi-inclusive (ep -> e’hadron(s)X) and exclusive (ep -> e’pp) reactions • energy variability p: 50 – 250/325 e: 4 - 20 • large acceptance absolutely crucial (both mid and forward-rapidity) • particle identification is crucial • e, p, K, p, n over wide momentum range and scattering angle • excellent secondary vertex resolution (charm) • particle detection to very low scattering angle • around 1o in e and p/A direction in contradiction to strong focusing quads close to IP • small systematic uncertainty (~1%/~3%) for e/p polarization measurements • very small systematic uncertainty (~1%) for luminosity measurement • eA-physics • requirements very similar to ep • challenge to tag the struck nucleus in exclusive and diffractive reactions. • difference in occupancy must be taken into account
Energies Simulated in RAPGAP EICC @ Stony Brook, January 2010
(M)eRHIC Luminosities Some luminosity numbers: for MeRHIC without CEC 4 x 250: 1x1032 cm-2s-1 for MeRHIC with CEC 4 x 250: 1x1033 cm-2s-1 for eRHIC with CEC: 20 x 325: 2.8x1033 cm-2s-1 30 x 325 with b* of 5cm: 1.4x1034 cm-2s-1 as the the luminosity does not depend on the energy of electron beam you can write it as for eRHIC with CEC: 2.8 1033* Ep/250 cm-2s-1 so you can easily scale it going to 20x100 for example so for MeRHIC assuming 50% operations efficiency one week corresponds to 0.5 * 604800(s in a week) * (1x1032 cm-2s-1) = 3*1037 cm-1 so 30pb-1 for eRHIC with CEC we collect in one week ~1fb anoperations efficiency of 50% is low, but conservative at this moment. For EIC systematic errors will be the limiting factor i.e., g1, FL,Dg, Dq EICC @ Stony Brook, January 2010
The √s vs. minimum luminosity landscape W2-dependence of c.s. neglected Diffraction exclusive DIS (PS & VM) electro-weak exclusive DIS (DVCS) H1/ZEUS: ~1031cm-2s-1 Hermes: 5x1031-1033 semi-inclusive DIS inclusive DIS 20x100 20x250 10x100 4x50 4x100 BNL S&T-Review, July 2009
Momentum vs. theta of scat. electron Proton Energy 50 GeV 100 GeV 250 GeV As more symmetric beam energies as more the scattered lepton goes forward Electron Energy 4 GeV10 GeV 20 GeV EICC @ Stony Brook, January 2010
pe: 0-1 GeV pe: 1-2GeV pe: 3-4GeV pe: 2-3GeV 4x50 Q2>1GeV2 20o after 1m ~35cm away from beam pipe 4x100 4x250 EICC @ Stony Brook, January 2010
Momentum vs. angle of pions • Whatdo we see: • For DIS: distribution is more “smeared” as energy balance becomes more symmetric • For diffractive: majority of pions at easily accessible angles, either forward or backward depending on proton/electron energy Same CM energy (63.3 GeV)
t for exclusive VM vsp’ angle t=(p4-p2)2 = 2[(mpin.mpout)-(EinEout - pzinpzout)] t=(p3–p1)2 = mρ2-Q2- 2(Eγ*Eρ-pxγ*pxρ-pyγ*pyρ-pzγ*pzρ) 4 x 50 4 x 100 • very strong correlation between • t and “recoiling” proton angle • Roman pots need to be very • well integrated in the lattice • resolution on t! 4 x 250 EICC @ Stony Brook, January 2010
IR-Design for MeRHIC IP-2 • no synchrotron shielding included • allows p and heavy ion decay product tagging • IP-2: height beam-pipe floor ~6’ (with digging ~10’) EICC @ Stony Brook, January 2010
First ideas for a detector concept Solenoid (4T) Dipole 3Tm Dipole 3Tm FPD FED // // ZDC • Dipoles needed to have good forward momentum resolution • Solenoid no magnetic field @ r ~ 0 • DIRC, RICH hadron identification p, K, p • high-threshold Cerenkov fast trigger for scattered lepton • radiation length very critical low lepton energies EICC @ Stony Brook, January 2010
MeRHIC Detector in Geant-3 Silicon Strip detector ala Zeus central tracking ala BaBar Drift Chambers Drift Chambers ala HERMES FDC EM-Calorimeter LeadGlas Dual-Radiator RICH ala HERMES High Threshold Cerenkov fast trigger on e’ e/h separation • DIRC: not shown because of cut; modeled following Babar • no hadronic calorimeter in barrel, because of vertical space @ IP-2 EICC @ Stony Brook, January 2010
BACKUP EICC @ Stony Brook, January 2010
ERL-based eRHIC Design 5 mm 5 mm 5 mm 5 mm 20 GeV e-beam 16 GeV e-beam Common vacuum chamber 12 GeV e-beam 8 GeV e-beam 2 x 200 m SRF linac 4 (5) GeV per pass 5 (4) passes (M)eRHIC detector Gap 5 mm total 0.3 T for 30 GeV Polarized e-gun 10-20 GeV e x 325 GeV p 130 GeV/u Au possibility of 30 GeV @ low current operation Beam dump MeRHIC detector Coherent e-cooler PHENIX STAR 4 to 5 vertically separated recirculating passes EICC @ Stony Brook, January 2010
Zeus @ HERA I EICC @ Stony Brook, January 2010
Zeus @ HERA II EICC @ Stony Brook, January 2010
Hera I vs. Hera II Focusing Quads close to IP Problem for forward acceptance EICC @ Stony Brook, January 2010
ELIC Detector/IR Layout by R. Ent solenoid ion FFQs dipole bending scattered protons “up” ions electrons IP with crossing angle electron FFQs Distance from IP to electron FFQ: 6 m to ion FFQ: 9m Modest electron final focusing quad field requirements quads can be made small EICC @ Stony Brook, January 2010
ELIC detector cartoon - Oct. 09 by R. Ent 8 meters (for scale) Offset IP? 140 degrees TOF HCAL ECAL Tracking DIRC HTCC RICH dipole dipole 1st (small) electron FF quad @ 6 m solenoid Additional electron detection (tracking, calorimetry) for low-Q2 physics not on cartoon Ion beam e beam EICC @ Stony Brook, January 2010
Event kinematics produced hadrons (p+) D I S 4x250 4x50 20x250 DIS: small theta important D I F F R A C T I V E without magnetic field EICC @ Stony Brook, January 2010