e.c. aschenauereic ew meeting, w&m, va, may 20101
Post on 01-Apr-2015
215 Views
Preview:
TRANSCRIPT
EIC EW Meeting, W&M, VA, May 2010 1
An IR- and Detector Design for all the Stages of eRHIC
E.C. Aschenauer
EIC EW Meeting, W&M, VA, May 2010 2
eRHIC Scope
e-
e+
p
Unpolarized andpolarized leptons4-20 (30) GeV
Polarized light ions (He3) 215 GeV/u
Light ions (d,Si,Cu)Heavy ions (Au,U)50-100 (130) GeV/u
Polarized protons50-250 (325) GeV
Electron accelerator RHIC
70% e- beam polarization goalpolarized positrons?
Center mass energy range: √s=28-200 GeV; L~100-1000xHera
longitudinal and transverse polarisation for p/He-3 possible
e-
Mission: Studying the Physics of Strong Color Fields
E.C. Aschenauer
EIC EW Meeting, W&M, VA, May 2010 3
The Relativistic Heavy-Ion Collider @ BNL
E.C. Aschenauer
RHICBRAHMSPHOBOS
PHENIXSTAR
AGS
TANDEMS
v = 0.99995⋅c = 186,000 miles/sec
ERL Test Facility
12 o’clock proposed
RF
BOOSTER
LINACEBIS
EIC EW Meeting, W&M, VA, May 2010 4
The 1st/2nd incarnation of a staged eRHIC
E.C. Aschenauer
STAR
PH
EN
IX
3 pass 4 GeV ERL
Polarized
e-gun
Beamdump
MeRHICdetector
2 x 200 m SRF linac4 (5) GeV per pass5 (4) passes
4 to 5 vertically separatedrecirculating passes
Gap 5 mm total0.3 T for 30 GeV
5 mm
5 mm
5 mm
5 mm
20 GeV e-beam
16 GeV e-beam
12 GeV e-beam
8 GeV e-beam
Com
mon
vacu
um
ch
am
ber
10-20 GeV e x 325 GeV p
130 GeV/u Aupossibility of 30 GeV @
low current operation
STAR
PH
EN
IX
Polarized
e-gun
Beamdump
Cohere
nt
e-c
oole
r
eRHICdetector
WHY IP-12? have Experimental Hall @ IP-12 size of STAR
fully staged detector from MeRHIC to eRHIC vertical space much bigger (room for HCal) need to buy magnets only once can stage detector components, i.e. hadronic calorimeter no moving of components (IP2 IP12) systematics reduced same detector for all energies
MeRHICeRHIC with
CeC
p (A) e p (A) e
Energy, GeV250 (100
)4
325 (125)
20 <30
>
Number of bunches
111 166
Bunch intensity (u) , 1011 2.0
0.31
2.0 (3)
0.24
Bunch charge, nC
32 5 32 4
Beam current, mA
320 50 42050 <10
>
Normalized emittance, 1e-6 m, 95% for p / rms for e
15 73 1.2 25
Polarization, % 70 80 70 80
rms bunch length, cm
20 0.2 4.9 0.2
β*, cm 50 50 25 25
Luminosity, x 1033, cm-2s-1
0.1 -> 1 with CeC
2.8
5
STAR
ePH
EN
IX100m
|--------|
6 pass 2.5 GeV ERL C
ohere
nt
e-cooler
22.5 GeV
17.5GeV
12.5 GeV
7.5 GeV
Com
mon
vacu
um
ch
am
ber
27.5 GeV
2.5 GeV
Beam-dump
Polarized e-gun eRHIC
detector
25 GeV
20 GeV
15 GeV
10 GeV
Com
mon
vacu
um
ch
am
ber
30 GeV
5 GeV
0.1 GeV
The latest design of eRHIC
The mostcost
effective design
RHIC: 325 GeV p or 130 GeV/u Au
eRHIC staging all-in tunnel
EIC EW Meeting, W&M, VA, May 2010 6
© V. Litvinenko
LINAC SS and ARC Design
E.C. Aschenauer
1.27 m beam high
30 GeV e+ ring
30 GeV ERL 6 passes
HE ERL passesLE ERL passes
30 GeV 25 GeV20 GeV15 GeV 10 GeV 5 GeV
1.27 m beam highe+ ring
200 m ERL Linac
© V. Litvinenko
EIC EW Meeting, W&M, VA, May 2010 7
IR-Design
0.4
4 m
Q5D5
Q4
90 m
10 mrad 0.3
29 m
3.67 mrad
60 m10 20 30
0.1
88036 m
18.8
m
16.8
m
6.33 mrad
4 m
© D.Trbojevic
30 GeV e-
325 GeV p
125 GeV/u ions
eRHIC - Geometry high-lumi IR with β*=5 cm, l*=4.5 mand 10 mrad crossing angle
E.C. Aschenauer
m
Spin
rotator
EIC EW Meeting, W&M, VA, May 2010 8
eRHIC – Geometry high-lumi IR
1.6 m
1 32 4 5 6
0.85 m
7
10 mrad
5.4
cm
8.4
cm
10.4
cm
1 m
© D.Trbojevic
E.C. Aschenauer
Two designs of the IR exist for both low luminosity (~ 3x1033) and high luminosity (~ 2x1034) depends on distance IR to focusing quads
By using a crossing angle (and crab cavities), one can have energy-independent geometries for the IRs and no synchrotron radiation in the detectors
Big advantage in detecting particles at low angle can go as low as 0.75o at hadron side |h| < 5.5 Beam-p: y ~
6.2
m
eRHIC IR1
p /A e
Energy (max), GeV 325/130 20
Number of bunches 166 74 nsec
Bunch intensity (u) , 1011 2.0 0.24
Bunch charge, nC 32 4
Beam current, mA 420 50
Normalized emittance, 1e-6 m, 95% for p / rms for e
1.2 25
Polarization, % 70 80
rms bunch length, cm 4.9 0.2
β*, cm 5 5
Luminosity, cm-2s-1 1.46 x 1034
(including hour-glass effect h=0.851)
Luminosity for 30 GeV e-beam operation will be at 20% level
EIC EW Meeting, W&M, VA, May 2010 9
(M)eRHIC Luminosities
E.C. Aschenauer
Old Design: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
New Design:for eRHIC with CEC: 20 x 325 with b* of 5cm: 1.4x1034 cm-2s-1
as the the luminosity does not depend on the energy of electron beam youcan write it as for eRHIC (new design): 1.4 1034* Ep/325 cm-2s-1
so you can easily scale it going to 20x100 for example
so for eRHIC assuming 50% operations efficiency one week corresponds to0.5 * 604800(s in a week) * (1.4x1034 cm-2s-1) = 4*1039 cm-1 so 4000pb-1
an operations 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
EIC EW Meeting, W&M, VA, May 2010 10
Questions about QCD
Confinement of color, or why are there no free quarks and gluons at a long distance? A very hard question to answer
What is the quark-gluon structure inside a hadron?Probes to “see” and “locate” the quarks and gluons, withoutdisturbing them or interfering with their dynamics?
How do quarks and gluons form color neutral hadrons?Probes to “monitor” the hadronization process?
How to understand the spin of a hadron? Hadrons are a composite particle of quarks and gluons What is the physics behind the QCD mass scale?
E.C. Aschenauer
It represents the difference between QED and QCD Can’t “see” it directly, but, it is behind the answers to all these questions
The key to the solutionThe Gluon
Lets try to answer: What is the role of gluons and gluon self-interactions in nucleons and nuclei? What is the internal landscape of the nucleons?
What is the nature of the spin of the proton? What is the three-dimensional spatial landscape of nucleons?
What governs the transition of quarks and gluons into pions and nucleons?
EIC EW Meeting, W&M, VA, May 2010 11
The √s vs. minimum luminosity landscape
E.C. Aschenauer
semi-inclusive DIS
inclusive DIS
Diffraction
electro-weak
4x10010x100 20x100 20x250
exclusive DIS (DVCS)
exclusive DIS (PS & VM)
4x50
H1/ZEUS:~1031cm-2s-1
Hermes:5x1031-1033
W2-dependence of c.s. neglected
EIC EW Meeting, W&M, VA, May 2010 12
Detector Requirements from Physics
Detector must be multi-purpose Need the same detector for inclusive (ep -> e’X), semi-
inclusive (ep -> e’hadron(s)X), exclusive (ep -> e’pp) reactions and eA interactions
Able to run for different energies (and ep/A kinematics) to reduce systematic errors Ability to tag the struck nucleus in exclusive and diffractive
eA reactions Needs to have large acceptance
Cover both mid- and forward-rapidity particle detection to very low scattering angle; around 1o in e
and p/A direction particle identification is crucial
e, p, K, p, n over wide momentum range and scattering angle excellent secondary vertex resolution (charm)
small systematic uncertainty for e,p-beam polarization and luminosity measurement
E.C. Aschenauer
EIC EW Meeting, W&M, VA, May 2010 13
Momentum vs. theta of scat. electron
Proton Energy50 GeV 100 GeV 250 GeV
Ele
ctr
on
En
erg
y 4
GeV
1
0 G
eV
2
0 G
eV
E.C. Aschenauer
As more symmetricbeam energies
as more thescattered lepton
goes forward
EIC EW Meeting, W&M, VA, May 2010 14E.C. Aschenauer
4x50
4x100
4x250
pe: 0-1 GeV pe: 1-2 GeV pe: 2-3 GeV pe: 3-4 GeV
No dependence on hadron beam energyQ2>0.1GeV2
4GeV >5o
10GeV >2o
20GeV >1o
EIC EW Meeting, W&M, VA, May 2010 15
Momentum vs. angle of pions
Same CM energy (63.3 GeV)
What do 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
E.C. Aschenauer
16
t for exclusive VM vs p’ angle
E.C. Aschenauer
EIC EW Meeting, W&M, VA, May 2010
4 x 50 4 x 100
4 x 250
very strong correlation between t and “recoiling” proton angle Roman pots need to be very well integrated in the lattice resolution on t!
t=(p4-p2)2 = 2[(mpin.mp
out)-(EinEout - pz
inpzout)] t=(p3–p1)2 = mρ
2-Q2 - 2(Eγ*Eρ-pxγ*px
ρ-pyγ*py
ρ-pz
γ*pzρ)
EIC EW Meeting, W&M, VA, May 2010 17
A detector integrated into IR
E.C. Aschenauer
ZDC
FPD
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
FED
a lot of space for polarimetryand luminositymeasurements
EIC EW Meeting, W&M, VA, May 2010 18
Can we detect DVCS-protons and Au break up p
E.C. Aschenauer
track the protons through solenoid, quads and dipole with hector
proton track Dp=10% proton track Dp=20%
proton track Dp=40%
Equivalent to fragmenting protonsfrom Au in Au optics (197/79:1 ~2.5:1)
DVCS proto
ns are
fine, need m
ore optim
izatio
n for b
reak-u
p proto
ns
EIC EW Meeting, W&M, VA, May 2010 19
eRHIC Detector in Geant-3
E.C. Aschenauer
DIRC: not shown because of cut; modeled following Babar no hadronic calorimeter in barrel yet
investigate ILC technology to combine mID with HCAL
Drift Chambers central tracking
ala BaBar
Silicon Stripdetectorala Zeus
EM-CalorimeterLeadGlas
High ThresholdCerenkov
fast trigger on e’e/h separation
Dual-Radiator RICH
ala HERMES
Drift Chambers ala HERMES FDC
Need to adopt G
eant-3 m
odel to new IR
conce
pt
EIC EW Meeting, W&M, VA, May 2010 20
MeRHIC Detector in Geant-3
E.C. Aschenauer
EIC EW Meeting, W&M, VA, May 2010 21
More Detector Concepts in the same framework
E.C. Aschenauer
Detector optimized fordiffractive physicsby Allen Caldwell
“eSTAR”
EIC EW Meeting, W&M, VA, May 2010 22
STAR @ RHIC
Heavy Flavor Tracker (2013)
Tracking: TPC
Forward Gem Tracker(2011)
Electromagnetic Calorimetry:BEMC+EEMC+FMS(-1 ≤ η ≤ 4)
Particle ID: TOF
Full azimuthal particle identification over a broad range in pseudorapidity
Upgrades:Muon Tracking Detector HLT
E.C. Aschenauer
EIC EW Meeting, W&M, VA, May 2010 23
Kinematics at 4+100
Scattered electron Scattered jet
4x100 open kinematics: scatters the electron and jet to mid-rapidityForward region (FMS): Electron either Q2 < 1 GeV, or very high x and Q2
Jet either very soft or very hardNote: current thinking has hadron in the blue beam: optimized for high x and Q2
E.C. Aschenauer
EIC EW Meeting, W&M, VA, May 2010 24
Current PHENIX Detector at RHIC
MPC 3.1 < | h | < 3.9 2.5o < Q < 5.2o Muon Arms 1.2 < | h | < 2.4 South: 12o < Q < 37o
North: 10o < Q < 37o
Central Arms | h | < 0.35 60o < Q < 110o
e-
electrons will not make it to the south muon arm to much material
would like to have hadrons in blue beam and leptons in yellow beam direction
E.C. Aschenauer
EIC EW Meeting, W&M, VA, May 2010 25
What will the current PheniX see4x100
pe: 0-1 GeV pe: 1-2 GeV pe: 2-3 GeV pe: 3-4 GeV
4x100 4x100
Current PheniX detector not really useable for
DISacceptance not matched to DIS kinematics
BUT ….
E.C. Aschenauer
EIC EW Meeting, W&M, VA, May 2010 26
HCALEMCAL
Preshower
The new PheniX Spectrometer
Coverage in |h| =< 4 (2o < q < 30o) 0.1 < Q2 < 100 (5o – 175o) need an open geometry detector planes for next decadal plan
replace current central detector with a new one covering |h| =< 1replace South muon arm by a endcap spectrometer
60cm
2T SolenoidEMCAL
HCAL
Silicon TrackerVTX + 1 layer
Silicon TrackerFVTX
1.2 < h < 2.7 8o < q < 37o
North Muon Arm
RICH
68cm
IP
80cm
145cm
5o @ 2m 17.4 cm dy
E.C. Aschenauer
Summary:
the new PheniX detector can make
important measurements
in ep/eA
Lets integrate it fully into the design
and the next decadal plan
EIC EW Meeting, W&M, VA, May 2010 27
Summary
A lot of change/progress since the last EIC Collaboration meeting new eRHIC design more elegant and staging is very
naturaly included working on costing of the new version test many detector options eSTAR, ePHENIX and a
dedicated detectoreSTAR & ePHENIX look promising with some restrictions
need to adjust the dedicated detector design fully to the new IR design
will integrate luminosity and e/p-polarisation measurements on the next step
Need input from the EW community what is required for detector, machine and IR design
Submitted first detector LDRD to BNL high resolution vertex detector based on CMOS pixel
E.C. Aschenauer
EIC EW Meeting, W&M, VA, May 2010 28
Quads for β*=5 cm
© B.Parker
E.C. Aschenauer
EIC EW Meeting, W&M, VA, May 2010 29
Luminosities in electron-hadron collisions
ELIC
eRHIC IIeRHIC
e+A facilities© 2010 Plot by A.Accardi
excepteRHIC luminosity by V.
Litvinenko
HERA II
E.C. Aschenauer
EIC EW Meeting, W&M, VA, May 2010 30
Questions about QCD (biased list)
Confinement of color, or why there is no free quarks and gluons at a long distance? A very hard question to answer
What is the quark-gluon structure inside a hadron?Probes to “see” and “locate” the quarks and gluons, withoutdisturbing them or interfering with their dynamics?
How quarks and gluons form color neutral hadrons?Probes to “monitor” the hadronization process?
How to understand the spin of a hadron?A composite particle of quarks and gluons
What is the physics behind the QCD mass scale? …
E.C. Aschenauer
It represents the difference between QED and QCD Can’t “see” it directly, but, it is behind the answers to all these questions
The key to the solutionThe Gluon
EIC EW Meeting, W&M, VA, May 2010 31
Energies Simulated for kinematics
Beam EnergiesEe + Ep [GeV]
Center-of-mass Energy [GeV]
Events Produced
4+50 28.34+100 40.010+50 44.74+250 63.3
10+100 63.3 One million20+50 63.3
20+100 89.410+250 10020+250 141
E.C. Aschenauer
EIC EW Meeting, W&M, VA, May 2010 32E.C. Aschenauer
STAR
PH
EN
IX
2 x 200 m SRF linac4 (5) GeV per pass5 (4) passes
Polarized e-gun
Beamdump
4 to 5 vertically separatedrecirculating passes
Cohere
nt
e-c
oole
r
5 mm
5 mm
5 mm
5 mm
20 GeV e-beam
16 GeV e-beam
12 GeV e-beam
8 GeV e-beam
Com
mon
vacu
um
ch
am
ber
Gap 5 mm total0.3 T for 30 GeV
MeRH
IC
dete
ctor
10-20 GeV e x 325 GeV p 130 GeV/u Au
possibility of 30 GeV @low current operation
The 1st incarnation from a staged eRHIC
EIC EW Meeting, W&M, VA, May 2010 33
IR-Design for MeRHIC IP-2
E.C. Aschenauer
synchrotron shielding omitted allows p and heavy ion decay product tagging IP-2: height beam-pipe floor ~6’ (with digging ~10’)
limits detector design no HCal in central detector
EIC EW Meeting, W&M, VA, May 2010 34
eSTAR
ePH
EN
IX
eRHIC staging all-in tunnel energy of electron beam is increasing from 5 GeV to 30 GeV by building-up the linacs
2 SRF linac1 -> 5 GeV per pass4 (6) passes
Vertically separatedrecirculating passes.# of passes will be chosen to optimize eRHIC cost
Cohere
nt e-co
ole
r
5 mm
5 mm
5 mm
5 mm
20 GeV e-beam
15 GeV e-beam
10 GeV e-beam
5 GeV e-beam
Com
mon
vacu
um
ch
am
ber
Gap 5 mm total0.3 T for 30 GeV
eRHIC detector
inje
ctor
RHIC: 325 GeV p or 130 GeV/u Au
The mostcost
effective design
© V. Litvinenko
The latest design of eRHIC
E.C. Aschenauer
top related