The BoNuS Detector Concept Design Status Howard Fenker March 11, 2005.
Large/Huge Detector Concept
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Transcript of Large/Huge Detector Concept
Large/Huge Detector Concept
9. Nov. 2004
@7th ACFA LCWS in Taipei
Y. Sugimoto
KEK
Background
History of ACFA detector study 1992 Dec. “JLC-I” report (JLC Detector)
2T solenoid, R=4.5m Compensating EM- and H-CAL, 2.5<R<4.0m Small-cell Jet chamber, 0.45<R<2.3m, L=4.6m
2001 Nov. “ACFA report” 2003 Sep. “GLC report” (GLC Detector)
3T solenoid, R=4m: Pair B.G. suppression Compensating EM- and H-CAL, 1.6<R<3.4m Small cell Jet chamber, 0.45<R<1.55m, L=3.1m ( Keep pt
min same as before) Degraded pt res.
2004 Aug. ITRP technology choice Good chance to re-start a new detector optimization study Regional study Inter-regional (world-wide) study Milestone: Detector cost estimation at the end of 2005
Large/Huge detector study so far
Actually, discussion on Large/Huge detector study has started before the ITRP decision Started discussion after LCWS2004 Brief presentation at Victoria US WS (Jul.2004) Presentation at Durham ECFA WS (Sep.2004) Detector full simulator (JUPITER) construction on going
Discussion on the key components has started still earlier TPC R&D for GLC detector started in 2003 R&D for the calorimeter of GLC detector optimized for PFA
(digital calorimeter) has proposed in Aug. 2003
Design Concept
Basic design concept
Performance goal (common to all det. concepts)
Vertex Detector:
Tracking:
Jet energy res.:
Detector optimized for Particle Flow Algorithm (PFA) Large/Huge detector concept
GLC detector as a starting point Move inner surface of ECAL outwards to optimize for PFA Larger tracker to improve pt/pt
2 Re-consider the optimum sub-detector technologies based on th
e recent progresses
EEE
pp
pIP
tt
/3.0/
105/
sin/105)(52
2/3
Optimization for PFA
Jet energy resolution jet
2 = ch2 +
2 + nh2 + confusion
2 + threashold2
Perfect particle separation: Charged-/nh separation
Confusion of /nh shower with charged particles is the source of confusion Separation between charged particle and /nh shower is important
Charged particles should be spread out by B field Lateral size of EM shower of should be as small as po
ssible ( ~ Rmeffective: effective Moliere length)
Tracking capability for shower particles in HCAL is a very attractive option Digital HCAL
EEjet /%15~/
Optimization for PFA
Figure of merit (ECAL): Barrel: B Rin
2/ Rmeffective
Endcap: B Z2/ Rmeffective
Rin : Inner radius of Barrel ECAL Z : Z of EC ECAL front face (Actually, it is not so simple. Even with B=0, photon energy inside a cer
tain distance from a charged track scales as ~Rin2)
Different approaches B Rin
2 : SiD B Rin
2 : TESLA
B Rin2 : Large/Huge Detector
Effective Moliere Length
Absorber W : Rm ~ 9mm Pb : Rm ~ 16mm
Gap : Sensor + R.O. elec + etc.
xa xg
Effective Moliere Length = Rm (1+xg/xa)
Central Tracker
Figure of merit:
samplings ofNumber :
length Tracking :
field Magnetic :
resolution Spatial :
4
7203.3 )(22
n
L
B
nBLtptp
n is proportional to L if sampling pitch is constant
5.22
1
BLp
p
t
t
A possible modification from GLC detector model
Larger Rmax (2.0m) of the tracker and Rin (2.1m) of ECAL TPC would be a natural solution for such a large tracker
Keep solenoid radius same:
Somewhat thinner CAL (but still 6), but does it matter? Use W instead of Pb for ECAL absorber
Effective Rm: 25.5mm 16.2mm (2.5mm W / 2.0mm Gap) Small segmentation by Si pad layers or scintillator-strip layers
Put EC CAL at larger Z (2.05m2.8m) Longer Solenoid Preferable for B-field uniformity if TPC is used
It is preferable Zpole-tip < l* (4.3m?) both for neutron b.g. and QC support (l* :distance between IP and QC1)
Comparison of parametersSiD TESLA JLC GLC GLD [1] LD
Solenoid B(T) 5 4 2 3 3 3
Rin(m) 2.48 3.0 4.25 3.75 3.75 3.7
L(m) 5.8 9.2 9.1 6.8 9.86 9.4
Est(GJ) 1.4 2.3 1.1 1.8 1.7
Main Tracker
Rmin (m) 0.2 0.36 0.45 0.45 0.4 0.5
Rmax(m) 1.25 1.62 2.3 1.55 2.0 2.0
BL2.5 5.7 7.1 9.3 3.8 9.7 8.3
m 7 150 100 85 150 150
Nsample 5 200 100 50 220 144
pt/pt2 3.6e-5 1.5e-4 1.3e-4 2.9e-4 1.2 e-4
1.6e-4
[1] GLD is a tentative name of the Large/Huge detector model. All parameters are tentative.
Comparison of parametersSiD TESLA JLC GLC GLD LD
ECAL Rin (m) 1.27 1.68 2.5 1.6 2.1 2.0
BRin2 8.1 11.3 12.5 7.7 13.2 12.0
Type W/Si W/Si Pb/Sci Pb/Sci (W/Sci) Pb/Sci
Rmeff (mm) 18 24.4 21.3 25.5 16.2 21.3
BRin2/Rm
eff 448 462 588 301 817 565
Z (m) 1.72 2.83 2.9 2.05 2.8 3.0
BZ2/Rmeff 822 1311 792 494 1452 1271
X0 21 24 29 27 27 29
E+H
CAL
5.5 5.2 6.9 7.3 6.0 6.9
t (m) 1.18 1.3 1.5 1.8 1.4 1.7
Detector size
Area of EM CAL
(Barrel + Endcap) SiD: ~40 m2 / layer TESLA: ~80 m2 / layer GLD: ~ 100 m2 / layer (JLC: ~130 m2 / layer)
• EM Calorimeter
Global geometry(All parameters are tentative)
Global geometry
Global geometry
GLD is smaller than CMS “Large” is smaller than “Compact”
Merits and demerits of Large/Huge detector Merits
Advantage for PFA Better pt and dE/dx resolution for the main tracker Higher efficiency for long lived neutral particles (Ks, , and un
known new particles) Demerits
Cost ? – but it can be recovered by Lower B field of 3T (Less stored energy) Inexpensive option for ECAL (e.g. scintillator)
Vertex resolution for low momentum particles Lower B requires larger Rmin of VTX because of beam background
(IP)~5 10/(psin3/2) m is still achievable using wafers of ~50
m thick
Detector Components
Detector components
EM Calorimeter Small Rm
eff W radiator Make gaps as small as possible
Small segmentation : seg < Rmeff
Hadron Calorimeter Options
Absorber: Pb or Fe ? Sensor: Scintillator or GEM ? Digital or not digital ? Tail catcher behind solenoid needed?
Choice of calorimeter options depends on the results of future detector R&D and detector simulation
Detector components
Main tracker TPC is a natural solution for the Large tracker
Positive ion feedback (2- background) ? Study of gas with small diffusion
Small-cell jet chamber as an option (End plate would be much thicker than TPC)
Solenoid magnet Field uniformity in a large tracking volume
mmdzBz
Brz2max
0
(TESLA TDR)
Detector components
Muon system No serious study for GLD so far Design of muon system is indispensable for the solenoid/iron-yok
e design, which takes large fraction of the total cost Si inner/outer(?) tracker
Time stamping capability (separation of bunches)
High resolution Si strip det.
improves momentum resolution Si endcap tracker
Improves momentum resolution
in the end-cap region where main tracker coverage is limited
pt/pt2
TPC only 1.2e-4
TPC+VTX 4.5e-5
TPC+VTX+SIT 2.9e-5
SIT: =7m, 3 layersVTX: =3m, 5 layers
Detector components
Si forward disks / Forward Calorimeter Tracking down to cos=0.99 Luminosity measurement
Beam calorimeter Not considered in GLC detector At ILC, background is 1/200. Need serious consideration Careful design needed not to make back-splash to VTX Minimum veto angle ~5mrad (?) Physics
Si pair monitor Measure beam profile from r-phi distribution of pair
-background Radiation-hard Si detector (Si 3D-pixel)
Detector components Vertex Detector
Relatively low B-field of Large/Huge detector requires larger radius of the innermost layer Rmin (pair background)
Detailed simulation of background (pair b.g. and synchrotron b.g. ) is necessary to determine Rmin and beam pipe radius
R&D for thin wafer is very important to compensate for the degradation of I.P. resolution at low momentum due to large Rmin
TOF (?) K- separation by dE/dx of TPC has a gap in 0.9–2 GeV/c TOF system with =100ps can fill up the gap 1st layer of ECAL or additional detector ? What is the physics case?
Detector components
TOF (Cont.)
K-
Sep
ara
tion
()
Momentum (GeV/c)
Assumptions:TOF)=100psL=2.1mdE/dx)=4.5%
Status of the study
Full Simulator
Installation of a new geometry into a full simulator “JUPITER” is under way
Charged – separation
Simulation by A. Miyamoto Events are generated by Pyt
hia6.2, simulated by Quick Simulator
Particle positions at the entrance of EM-CAL
Advantage of Large/Huge detector is confirmed
Inconsistent with J.C.B’s result need more investigation
( )cutall events
all events
E d d
FE
dcut
F
Charged – separation
Simulation by J.C. Brient (LCWS2004)e+e- ZH jets at Ecm=500GeV
SD (6T)
TESLA (4T)
Magnet
ANSYS calculation by H.Yamaoka Field uniformity in trackin
g region is OK
Geometry of muon detector is tentative. More realistic input is necessary
1 .241187 .72356 1.688 2.171 3.135 3.618 4.583 5.547 6.03 6.994 7.477 8.442 8.924 9.889 10.853 11.336 12.301 12.783 13.748 14.712 15.195 16.16 16.642 17.607 18.089 19.054 20.019 20.501 21.466 21.948 22.913 23.877
1111111111
mmmmdzBz
Brz28.1max
0
Other studies
See presentations in parallel sessions and http://ilcphys.kek.jp/
Summary Optimization study of Large/Huge detector concept has just started GLC detector is the starting point of the Large/Huge detector, but its
geometry and sub-detector technologies will be largely modified A key concept of Large/Huge detector is optimization for PFA A milestone of this study is the detector cost estimation scheduled
at the end of 2005. A firm report backed up with simulation studies and detector R&D should be written
A lot of jobs including clarification of physics requirements, detector full/quick simulation, and detector R&D are awaiting us
Please join the Kick-off meeting:Date: Nov. 10 Time: 17:30 - 19:30 Place: Room 204
Backup slides
Beam Calorimeter is placed in the high background region
Same sign
Opposite sign
by T.AsoGLC Parameter, B=4T
Pair background track density