# Presentation: 089359

## D.Glenzinski
Wilson Fellow/Fermilab-CDF

(on behalf of the CDF and D0 Collaborations)

- Wilson Fellow/Fermilab-CDF
- (on behalf of the CDF and D0 Collaborations)

- Electroweak Prospects for TeVatron RunII

- ICHEP02, Amsterdam, Netherlands, 24-31 July 2002

## Data Sets for RunII EWK Physics:

-  100 pb-1/exp in RunI
-  2 fb-1/exp in RunIIa
-  l = e or 

-  RunI produced breadth of Electroweak physics results
-   and provided world’s only sample of top quarks
-  RunII physics EWK “program” basically the same
-  RunII Upgrades ought yield many precision (<1%) results

- D.Glenzinski, ICHEP02

## RunII TeVatron Upgrades:

-  RunIIa Luminosity Goals
-  5-8 E31 cm-2/sec (w/o Recycler)
-  10-20 E31 cm-2/sec (w/ Recycler)
-  integrated: 2-5 fb-1 (2004)
-  RunIIb Luminosity Goals
-  40-50 E31 cm-2/sec
-  integrated: 15 fb-1 (2007)
- (W), (Z) ~10% higher
- (tt) ~35% higher

_**RunII TeVatron Upgrades:**_

- D.Glenzinski, ICHEP02

## RunII Detector Upgrades:

-  CDF
-  8 layers of silicon (rmax=30 cm)
-  new drift chamber (COT)
-  extended lepton-ID (||>1)
-  displaced track trigger
-  D0
-  4 layers plus disks of silicon
-  new fiber tracker (CFT)
-  solenoid (2 Tesla)
-  extended lepton-ID (||>1)

- _Projections assume:_
- E and P resolutions
-    same/better RunI
- B-jet and lepton ID
-    extended to ||>1
- improved triggering

- D.Glenzinski, ICHEP02

## TeVatron RunII

- Steady collisions
- > Jun-01

- commissioning

- physics

- Results so far:
- 10-20 pb-1/exp

- At this early stage, it’s interesting to ask whether or not the detector performance looks consistent with those expectations.

-  Discuss present detector performance in the context of some   of RunII Electroweak measurements of particular importance.

- D.Glenzinski, ICHEP02

## Electroweak Physics at the TeVatron

_**Electroweak Physics at the TeVatron**_

- _Precision M__w__, M__top__:_
-  CDF/D0 direct  measurements compliment e+e- results
-  provide consistency checks
-  will improve indirect  constraints on MH w/i SM
- _Search for SM Higgs:_
-  Light Higgs discovery possible
-  Observation or not, SM will be
-     tested by comparison of MH to
-     indirect limits from EWK fit

-  discuss detector performance in the context of these measurements

- (status summer ’00)

- TeV RunI

- D.Glenzinski, ICHEP02

## Measuring Mw at the TeVatron

- understand E and _**P**_ scales and resolutions
- Calculate missing transverse momentum
- must model *U*nderlying event and recoil distributions, etc.
- From MT distribution extract measure of Mw
- sensitive to PDFs (use forward calorimeters)

_**Measuring Mw at the TeVatron**_

- which looks like this
- in the detectors:

- W production
- at the TeV:

- D.Glenzinski, ICHEP02

## Run1 W Mass

-                _From RunI_
-   CDF: 80.433 +/- 0.079 GeV
-      D0: 80.483 +/- 0.084 GeV
- Comb: 80.456 +/- 0.059 GeV
- After 2 fb-1 at RunII, expect
-     Mw=+/-30 MeV/exp
-  Mw(Wrld)=+/-15-20 MeV

** ****RunII projections assume detectors will perform similarly**
**     ****to RunI so that, M uncertainty to ~scale w/ statistics**
** ****How will P****t******** resolution scale with inst. Luminosity?**

- D.Glenzinski, ICHEP02

## Momentum Scales & Resolutions in RunII

- Use low lying resonances to get P scale/resolution

_**Momentum Scales & Resolutions in RunII**_

- =15 MeV

- 53k
- “golden”
- J/’

- CDF RunII
- Preliminary
- ~11 pb-1

-  already large statistics samples
- available to study tracking

- ~8 pb-1

- D.Glenzinski, ICHEP02

## D0’s Central Fiber Tracker Performance:

- Per layer hit efficiencies:
- (axial layers) = 99%
- (stereo layers) = 98%
-   (expect high tracking efficiency)

- Very different from RunI:
-    - fiber tracker
-    - r = 0.20-0.51 m
-    - 8 axial hits
-    - 8 stereo hits
-    - in 2T field
-    - (Pt)/Pt2(design) = 0.14%/GeV

- Alignment well underway, significant improvements expected.

- D.Glenzinski, ICHEP02

## CDF’s Central Outer Tracker Performance:

- “out of box”:
- hit) = 175 m
-    (TDR said 180 m)
- (Pt)/Pt2 < 0.13% GeV-1
-     (RunI = 0.10%)

- From W’ e events:
- (COT *tracking*) = 99 +/- 1%

-  expect further improvements
-           as alignment matures

- D.Glenzinski, ICHEP02

## Energy Scales & Resolutions in RunII

- Nominally, use E/P distributions to set absolute scale and resolution
- assumes P-scale/resolution thoroughly understood

_**Energy Scales & Resolutions in RunII**_

-  at this early stage, use Z’ee to estimate E resolution

- D.Glenzinski, ICHEP02

## D0’s ECAL Performance:

_**D0’s ECAL Performance:**_

- one electron ||<1.0
-  N(Z’ee) = 495

- _For central & forward:_
-  partial corrections included
-  (data)/(mc) < 1.30
-  w/ inclusion of full corrections
-   expect to meet expectations

- D.Glenzinski, ICHEP02

## CDF’s ECAL Performance:

_**CDF’s ECAL Performance:**_

- _For central & forward:_
-  includes dominant
-   corrections
-  (data)/(mc) < 1.05
-  ECAL resolution as
-   expected

- both electrons ||<1.0
-  N(Z’ee) = 247

- one electron ||>1.0
-  N(Z’ee) = 391

- D.Glenzinski, ICHEP02

## Extending lepton-ID:

_**Extending lepton-ID:**_

- extending Mw and asymmetry measurements to large ||
- reduces Mw PDF uncertainties (which are CDF/D0 correlated)

- both electrons ||>1.2
-  N(Z’ee) = 160

- Starting to collect control samples &
- performing first pass analyses to
- demonstrate thorough understanding
- of forward detectors.

- D.Glenzinski, ICHEP02

## Measuring Mtop at the TeVatron

_**Measuring M**__**top**__** at the TeVatron**_

- _Final states (2 B-jets + Ws)_:
-  - dilepton (2 W’l)
-  - lepton+jets (W’l,W’qq)
-  - all hadronic (2 W’qq)

- most important channel

- D.Glenzinski, ICHEP02

## Run1 Top Mass

-                From Run1
-   CDF: 176.1 +/- 6.6 GeV
-      D0: 172.1 +/- 7.1 GeV
- Comb: 174.3 +/- 5.1 GeV
- After 2 fb-1 at Run2, expect
-     Mtop=+/- 2-3 GeV/exp

-       Statistical: 5 GeV
-      Systematic
-         scale: 4 GeV
-  modeling: 2 GeV *
-         other: 2 GeV
- Sys Total: 5 GeV
-      *correlated among experiments

- _“__Typical” M__top__ Uncertainties/exp_

-  increased acceptance and tt gives factor of 50 in statistics
-   (RunIIa will have ~800 lepton+jet evts in mass sample, RunI ~20)
-   so expected RunIIa stat uncertainty: less than +/- 1GeV
-  reducing total systematic to 2 GeV level requires use of special
-     control samples (Z+jets, Z’bb, W’qq) too small to be of use in RunI

- D.Glenzinski, ICHEP02

## Top Mass: Combinatorics

_**Top Mass: **__**Combinatorics**_

- Combinatoric background a function of
- # of B-jet tags in events:
- 2, 6 or 12 jet-jet combos vs N(B-tag)
- For events with >= 1 b-tag:
**30%**** **correct jet assignment (black)
**20%**** **correct jets but wrong combination (yellow)
**50%**** **mismatch between parton and its jet (red)
- ie. extra jets from gluon radiation
- Increased B-tagging acceptance most important factor in improving Mtop
- increases statistics
- improves purity
- reduces combinatorics

- CDF RunI Simulation
- for Mtop=175 GeV

- improved Mtop sensitivity

- D.Glenzinski, ICHEP02

## D0’s Silicon Microstrip Tracker Performance:

-  Performing as expected
-  95% working channels (and regularly taking data)
-  precision alignment of “z”-strips underway

- w/ first pass alignment,
- for (beam)=30 m:
- (d0) = 20m

- D.Glenzinski, ICHEP02

## CDF’s Silicon VerteX Detector Performance:

- before alignment

- m

- after alignment

- m

- r

- r

- S/NHit efficiency >99% , (intrinsic 2strip r) =11m
-  Performing as expected
-  92% working channels (presently, 85% regularly taking data)
-  precision alignment of “z”-strips underway

- Ladder #

- D.Glenzinski, ICHEP02

## SM Higgs Search at the TeVatron

- Need to use H’bb
- and H’WW to
- maintain sensitivity
- over wide mass range

- D.Glenzinski, ICHEP02

## SM Higgs Search at the TeVatron

_**SM Higgs Search at the TeVatron**_

**LEP**

- Observation possible with >2 fb-1 of integrated luminosity
-  assumes good B-jet and lepton ID to full acceptance
-  assumes detector resolutions at least as good as RunI
-  assumes triggers efficient at large inst. luminosities

- D.Glenzinski, ICHEP02

## Triggers

_**Triggers**_

- _CDF rates_
-  now (L~1031):
-      L1/L2/L3 = 6000/240/30 Hz
-  goal (L~1032):
-      L1/L2/L3 = 50000/300/50 Hz

- _D0 rates_
-  now (L~1031):
-      L1/L2/L3 = 200/140/50 Hz
-  goal (L~1032):
-      L1/L2/L3 = 7000/1500/50 Hz

-  lepton triggers operating at high ... important to maintain
- at high instantaneous luminosities!

- D0 RunII Preliminary

- L3/L1 electron efficiency

- Pt(GeV)

- D.Glenzinski, ICHEP02

## SM Higgs Background Studies

_**SM Higgs Background Studies**_

-  continue to develop analyses which build confidence
- in background modeling/expectations for larger data sets

- H’WW’eein 9 pb-1 of data
-  do we understand our backgrounds?

- D0 RunII Preliminary

- D.Glenzinski, ICHEP02

## RunIIa: Electroweak Physics

_**RunIIa: Electroweak Physics**_

- With 2 fb-1:
-  Mw = 30 MeV/exp
-  Mtop = 3 GeV/exp
-  start having sensitivity
-   to SM MH>115 GeV

- Tevatron upgrades:
-  luminosities of 2x1032
-                    in 2 years
-  (W), (Z) ~10% higher
-  (tt) ~ 35% higher

- 2 fb-1 of RunII
- (per experiment)

- Detector upgrades:

-  increased B-jet and lepton ID   acceptance and triggering
-  performance on track to meet expectations

- EWK Prospects are good!

- D.Glenzinski, ICHEP02