arnaud lucotte isn-grenoble j/ e + e - selection at d runii arnaud lucotte (isn grenoble)...
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Arnaud Lucotte ISN-GrenobleArnaud Lucotte ISN-Grenoble
J/J/ee++ee-- selection at D selection at DRunIIRunII
Arnaud Lucotte Arnaud Lucotte (ISN Grenoble)(ISN Grenoble)
Introduction
A. J/ production at the TeVatron1. Prompt production: direct and c 2. Production from b decays3. Cross-sections at fnal
B. J/ detection with the upgrade D1. Upgrade detectors for J/Psi 2. Trigger Constraints at Run II 3. Trigger Architecture
C. Triggering on J/e+e- at D1. L1 and L2 Triggers2. Reconstruction 3. J/e+e- yields
Conclusion
Arnaud Lucotte ISN-GrenobleArnaud Lucotte ISN-Grenoble
Introduction: J/Psi at Run IIIntroduction: J/Psi at Run II
B Physics:B Physics:
bbar 50 b (10kHz@1032cm2s-1) w/ bbar<1/1000
dj
Violation CP dans le systeme Bd0 :
BS Oscillations
Bs0 DS (DS ) 2000 evts attendus
(~70 fs time resolution) Other b-topics:
Rare b Decays
Spectroscopy BC
Detector Calibration:Detector Calibration: Calibration:
CC, EC-EC, EC-CC
using Zee, , ee
Arnaud Lucotte ISN-GrenobleArnaud Lucotte ISN-Grenoble
J/J/ Production at TeVatron Production at TeVatron
1. Prompt Production of J/1. Prompt Production of J/ ’s ’s(a) direct production
Color Singlet Model (CSM) (see graphs)
built to describe ISR data
predicts direct processus is dominant
factor 30-50 discrepancy vs fnal data !
(b) production via c states
c states produced by
gluon fragmentation
pp c +X
c J/
Still not enough to
explain fnal data !
(c) modified direct production Color Octet Model (COM)
brings new predictions to direct production
better agreement w/ fnal data
~24% of prompt J/ from c
CDF
Arnaud Lucotte ISN-GrenobleArnaud Lucotte ISN-Grenoble
J/J/ Production at TeVatron Production at TeVatron
(a) Quarkonium Production (CSM)
1S0 3Pj
1S0 3Pj
1S0 3P0,2
1S0 3Pj
1S0 3Pj
1S0 3S1
3Pj
1S0 3Pj
g
g
g
g
gg
g
g g
gg
g
g
g
g
q
qqq
g
O(s3)
O(s3)
Arnaud Lucotte ISN-GrenobleArnaud Lucotte ISN-Grenoble
J/J/ Production at TeVatron Production at TeVatron
2. b-decay production2. b-decay production
(a) b-decays contributionCDF+D0: depends on pT
dp vs pT ,
3. J/3. J/ Production Cross-section Production Cross-sectionCDF central:
p>5GeV,<0.6
D0 all detector:dp vs
1-30% J/ from b-decays
D0
=17.42.6 nb
D0
production ~centrale
Arnaud Lucotte ISN-GrenobleArnaud Lucotte ISN-Grenoble
J/J/ Production at TeVatron Production at TeVatron
3. J/3. J/ signal at the TeVatron signal at the TeVatron
(a) Momentum:
pTJ/pT
B with pTB ~ MB ,
pTl ~ 2.5 GeV/c
lepton even softer for prompt
production
(b) Anglular distribution: J/more central (e+,e-) ã few degrees
Arnaud Lucotte ISN-GrenobleArnaud Lucotte ISN-Grenoble
Sole
noid
e,
Dete
cte
ur
de T
races
Silic
on
Vert
ex,
Pre
sh
ow
ers
Fib
res S
ci.
Bou
cliers
Ch
am
bre
s a
deri
ve
(Min
i-d
rift
) A
rrie
res
Scin
tillate
urs
Arr
iere
sS
cin
tillate
ur
Cen
tral
+ N
ou
velle E
lectr
on
iqu
e,
Tri
g,
DA
Q
DD Upgrade Upgrade
Arnaud Lucotte ISN-GrenobleArnaud Lucotte ISN-Grenoble
Constraints on a J/Constraints on a J/ e e--ee++ Trigger Trigger
Signal Characteristics:Signal Characteristics:
B J/ X : <pT(J/> 0.7 < pTB > w/ < pT
B > ~ MB
C J/ X: <pT(J/> 1.5 GeV/c
Calorimeter threshold as low as: ET 3.0-4.0 GeV
Constraints on J/Constraints on J/ triggering triggeringAgainst Dijet background: ~7 MHz @ 1032cm2s-1
w/ band width: ~1 kHz at L1 , ~100Hz at L2 - Needs:
L1: Combination Track + Preshower + Calorimeter AND CAL/PS coincidence by Quadrant
L2: Inv. Mass reconstruction etc...
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L2FW:Combine objects (e, , j)
L2FW:Combine objects (e, , j)
L1CAL
L2STT
Global L2
L2CFT
L2PS
L2Cal
L1PS /L1FT
L2Muon
L1Muon
Detector L1 Trigger L2 Trigger
7 MHz 8 kHz 1 kHz
CAL
FPSCPS
CFT
SMT
Muon
Trigger Architecture Trigger Architecture
(100 s)(4.2s)
L1FW: CAL towers, tracks, Muons• 128 available combinations (ORs) • Calorimeter vs Preshower + tracks • Calorimeter vs Tracks
L1FW: CAL towers, tracks, Muons• 128 available combinations (ORs) • Calorimeter vs Preshower + tracks • Calorimeter vs Tracks
Arnaud Lucotte ISN-GrenobleArnaud Lucotte ISN-Grenoble
L1-Central EM Triggering L1-Central EM Triggering
Detector-specific:Detector-specific:
EM Calorimeter
#tower (= 0.20.2) & ET > [2.5, 5, 7,
10] GeV
Central PreShower
#cluster = adjacent strips such: Estrip > 2-
5 MIPs Fiber Tracker
# signed trajectories / bin pT [1.5-3], [3-5],[5-10],
[10-] GeV/c counted in each 80 x 4.5o sectors
Global-Level (Framework):Global-Level (Framework):Coincidence by Quadrant: 1 tower EM + (1 CPS-cluster+Track pT /sector)
L1PS
L1CFT
L1FW
L1CAL
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L1-Forward EM Trigger L1-Forward EM Trigger
EM Calorimeter EM EM Calorimeter EM
tower ( = 0.20.2) & ET >[2.5, 5, 7, 10]
GeV
Forward PreShower Forward PreShower
PS cluster = adjacent strips w/ Estrip > 5-10
MIPs
electron = PS cluster (u or v) + MIP (u or v)
Global Trigger (Framework) Global Trigger (Framework) Coincidence by Quadrant
1 tour EM + 1 electron (u et v) FPS
Electron in FPS
Pb
L1CAL
L1PS
L1FW
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L2-Central EM TriggeringL2-Central EM Triggering
EM Calorimeter EM Calorimeter
- L1 calo tower as “seed”
- Total EM cluster Energy:ET
EM = ETSEED + ET
2nd_max
- EM Fraction:EMF = ET
EM/(ETEM+ET
HAD)
- Cluster Isolation:TISO = ET
EM/(ETEM +ET
HAD) (33 including “seed”)
Central Preshower:Central Preshower: - 3D cluster(u,v,x) e- tagged
Fiber TrackerFiber Tracker - convert L1 pT track pT
(Look Up Table) - extrapolate to EM(3)
Vertex Detector Vertex Detector - combine CFT tracks - re-fit tracks :
pT, , impact parameter
L2CAL
L2PS
L2CFT
L2CTT
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Forward-EM Trigger Forward-EM Trigger
Occupation dans le Preshower:Occupation dans le Preshower: Interactions/cros. <#> = 2.1 (Poisson) @ 2. 1032 cm2s-1
MIP detection: T>0.3 MIPocc = 7-10%
cluster detection:T > MIPsocc = 0.5-2.0%
Dijet+6mbias
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Forward EM Triggering Forward EM Triggering
Efficiency: Efficiency:
Background rates (QCD dijets):Background rates (QCD dijets):Pion Rejection
20-25% de conversions de 0 ‘s avant PS (avant/arr.)
PS+CAL: facteur 2-4 (eleve pour faibles pT )
Bkgd rejection: ET ~10 GeV: 700~Hz (CAL) vs 200 Hz
(CAL+PS)
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L1 Trigger J/L1 Trigger J/ e e--ee+ +
Efficiency:Efficiency:- central 25-30%- forward 5-10%
- depends on CAL thresh.ET
CAL 2.75-3.5 GeV
Dijet background:Dijet background:- Rate: 200-1000 Hz - controled with PS/CAL Quadrant Match PS/Track sector Match(4.5o) Threshold EFPS , & ET
CAL
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L2 Trigger J/L2 Trigger J/ e e--ee+ +
Efficiency:Efficiency:- Central 20-25%- Forward 4- 8%- depends on L1 CAL ET thresholds
Dijet Background:Dijet Background:- Rates: 50-100 Hz: region centrale - avant/arriere - Reduced by Mass Window
EM isolation Coincidence TT vs PS- reducible: vertex information (for b-decays)
2 tracks / large impact parameter SB = B/B
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DAQ / Trigger for PSDAQ / Trigger for PS
Signal Readout:Signal Readout:How is it possible to read such signal ?
Two thresholds - calibration: MIP detection (1 MIP 0.9 MeV) - cluster reconstruction (e,) 5 to 60 MIPs
Trigger and Readout: - L1: chips SIFT [0/1] (FPGA) - L2: chips SVX-II [analog] (pre-processors)
SIFT
SIFT
SVX
SVX
SIGNAL MIP
SIGNAL GERBE
Logique Trigger (FPGA’ s)
SIGNAL TRIGGER
VLPC
Scintillateur
Fibres WLS
Q
0.27 Q
0.09 Q
[5-160]fC [0-150]fC
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CP violation with BCP violation with B00dd J/J/KKSS
Projection pour Projection pour sin2sin2 (temps integre) (temps integre)
- efficacite reco des traces: 95%- Dmix 0.47 , Dfond = S(S+B) ~ 0.7
- Tag D2tag ~ 0.05
sin2 13.40 NRECO
Contraintes indirectes:Contraintes indirectes:
Sin2=0.75 0.09CERN-EP/98-133
Arnaud Lucotte ISN-GrenobleArnaud Lucotte ISN-Grenoble
ConclusionConclusion
TeVatron is a phenomenal source of J/ ’s
1. main source is from prompt decays2. most *relevant* source from b-decays3. production models still to be tested
D0 is adapted to select J/ee 1. Detectors are adapted: - Preshowers (high dynamical range) - Calorimeter (4 thresh. sets) -Tracker (tag and sign at L1)2. Triggering is feasible provided: - Preshower-Track info at L1 - Preshower-Calorimeter Match at L1 - L2 is *not* an issue for ee (it is for )
D0 will be able to make use of /ee1. detector calibration (minimize MW )2. B physics like CP violation