D Experiment

1
DØ Experiment

• Physicists
• Susan Blessing
• Sharon Hagopian
• Vasken Hagopian
• Stephan L. Linn
• Harrison B. Prosper
• Horst D. Wahl
• Bill Lee
• Silvia Tentindo-Repond
• Graduate Students
• Brian Connolly
• Russell Gilmartin
• Attila Gonenc
• Craig Group
• Jose Lazoflores
• Yuri Lebedev
• Sinjini Sengupta
• Undergraduate student
• Burnham Stokes

• Research Interests
• Top quarks
• Supersymmetry
• Leptoquarks
• Higgs
• Recent Work
• Measurement of top quark mass
• Search for leptoquarks
• Search for supersymmetric top quarks

2
CMS Experiment

• Physicists
• S. Hagopian
• V. Hagopian
• K. Johnson
• H.B. Prosper
• H.D. Wahl
• Engineers
• Maurizio Bertoldi
• James Thomaston
• Undergraduate student
• Lucas Naveira

• Research Interests
• Supersymmetry
• Higgs
• Recent Work
• RD of a laser-based monitoring system for the
  CMS calorimeter
• RD of devices to scan large scintillating tiles.
• Coordination of test beam experiments at CERN

3
Summary

• Dzero 2000 to 2005
• Will remain the main focus of our research
  program for the next seven years.
• We have a wonderful window of opportunity to make
  major contributions to our field.
• CMS 2005 and beyond
• The LHC will vastly increase our ability to probe
  Nature. We are very confident that CMS will have
  a profound impact on our understanding of
  particle physics.
• Hellaz 2003 (?) and beyond

4
Research Program of FSU HEP group

• DØ Experiment
• To study 2 TeV proton antiproton collisions
• Fermilab, Batavia, Illinois
• Next run begins in April 2001
• CMS Experiment
• To study 14 TeV proton antiproton collisions
• CERN, Geneva, Switzerland
• First run begins in 2005
• Hellaz Experiment
• To study 1 MeV neutrinos from the Sun. When?!!!

5
Collisions at the Tevatron

• pp Collisions Þ qq(g) Interactions

Fermilab
6
Questions at the Tevatron

• The Standard Model
• Electro-Weak (EM Weak Interacts)
• W,Z,g quarks leptons
• Most Accurate Theory ever !(but only for
  fundamental particles)
• Simple Processes Þ Real Tests
• QCD (Strong Force)
• gluons quarks
• High E Þ Accurate PredictionsLow E Þ Not a
  simple Theory
• Range of Es accessible for partons in proton
• Properties of Particles
• All Quarks and Leptons Produced(only place for
  top quark)
• All Gauge Bosons..almost
• What about the Higgs?

7
More Questions

• The SM works great !Why change it ?
• Has 18 arbitrary parametersÞ Where do they come
  from ?
• Is the Higgs really what we think it should be ?
• 2 Strategies
• Look Harder Precision
• Get a Bigger Hammer Energy
• The Tevatron is well suited to both of these
  strategies

8
Fermilab Upgrade
9
DÆ Upgrade
10
DÆ Upgrade Tracking

• Silicon Tracker
• Four layer barrels (double/single sided)
• Interspersed double sided disks
• 793,000 channels
• Fiber Tracker
• Eight layers sci-fi ribbon doublets (z-u-v, or z)
• 74,000 830 mm fibers w/ VLPC readout

1.1
cryostat

• Preshowers
• Central
• Scintillator strips
• 6,000 channels
• Forward
• Scintillator strips
• 16,000 channels
• Solenoid
• 2T superconducting

1.7
11
Silicon Tracker

1/2 of detector
50 cm
3
8 DisksH
12 Disks F
7 barrels
1/7 of the detector (large-z disks
not shown)
387k ch in 4-layer double sided Si barrel
(stereo)
405k ch in interspersed disks (double sided
stereo) and large-z disks
12
Silicon Tracker -Detectors

• Disks
• F disks wedge (small diameter)
• 144 double sided detectors, 12 wedges 1disk
• 50mm pitch, /-15 stereo
• 7.5cm long, from r2.5 to 10cm, at
  z6,19,32,45,50,55 cm
• H disk (large diameter)
• 384 single sided detectors
• 50 mm pitch
• from r9.5-20 cm, z 94, 126 cm
• Barrels
• 7 modular, 4 layer barrel segments
• single sided
• layers 1 , 3 in two outermost barrels.
• double sided
• layers 1, 3 have 90o stereo (mpxd 31)
• 50 100mm pitch, 2.1 cm wide
• layers 2,4 have small angle stereo (2o)
• 50 62.5mm pitch, 3.4 cm wide

12cm
two detectors wire bonded
13
Trigger Configuration
Detector
L1 Trigger
L2 Trigger
1 kHz
7 MHz
10 kHz
L2Cal
CAL
FPS CPS
L1PS
L2PS
Global L2
L2CFT
CFT
L2STT
SMT
L2 Muon
L1 Muon
Muon
L1FPD
FPD
L2 Combined objects (e, m, j)
L1 towers, tracks
14
Feynman Diagrams
15
Questions at the Tevatron

• The Standard Model
• Electro-Weak (EM Weak Interactions)
• W,Z,g quarks leptons
• Most Accurate Theory ever !(but only for
  fundamental particles)
• Simple Processes Þ Real Tests
• QCD (Strong Force)
• gluons quarks
• High E Þ Accurate PredictionsLow E Þ Not a
  simple Theory
• Range of Es accessible for partons in proton
• Properties of Particles
• All Quarks and Leptons Produced(only place for
  top quark)
• All Gauge Bosons..almost
• What about the Higgs?

16
More Questions

• The SM works great !Why change it ?
• Has 18 arbitrary parametersÞ Where do they come
  from ?
• Is the Higgs really what we think it should be ?
• 2 Strategies
• Look Harder Precision
• Get a Bigger Hammer Energy
• The Tevatron is well suited to both of these
  strategies

17
Illustrious History of DÆ

• DÆ Roll-In February 1992
• Run I 92-93 94-95 96Þ 125 pb-1 at 1.8 TeV
• gt450 Physicists (70 Grad Students)
• 50 Instititutions (10 countries)
• Approx 100 Publications..so far
• EW Physics
• Top Physics
• New Phenomena
• B Physics
• QCD
• Top co-Discovered March 95
• Mt 172.1 5.2 4.9 GeV/c2
• st 5.6 1.8 pb
• Ncand 57 Nbgd 20.6 2.4

18
(not so) Illustrious Hist.

• Higgs only Limits
• LEP Þ MH gt 89.3 GeV/c2
• No Physics Beyond SM found yet
• But there is Hope..

19
Our Friend the b-Quark

• Tag Top Decays
• tbW 100
• Tag Higgs (Hbb)
• G(Hff) µ mf2
• New Particles bs
• New Physics couples to mass
• CP Violation
• Matter / Antimatter Asymmetry
• Should be Large in B systems
• QCD
• perturb non-perturb boundary

20
Our EnemyRates

• Too Much Physics
• Collision Rate 10 MHz
• Data to Tape 20 Hz
• Trigger
• ID interesting events as quickly as possible
• 132 ns between collisions !
• 3 Level System in DÆ

21
Silicon Track Trigger

• Goals
• Sharpen PT Measurement
• Identify b-events
• B Event Properties
• Impact Param / Vertex Triggers

B Decay Products
B-Hadron Flight Length mms
Decay Vertex
Collision
Impact Parameter
22
Using Silicon Information

• Include Si hits on CFT Track in L2 trigger
• STT Preprocessor

SMTDetector
CFT Tracks(L1 Trig)
Cluster Finder
Associate Clustersto Tracks
50 ms Time Budget
Re-Fit Trackw/ Si Clusters
Global L2 Trigger