Tom Diehl

1
Report From the Physics Groups Status, Plans
Concerns

• Tom Diehl
• July 8, 2002
• Norman, Oklahoma

2
Preparation for this talk

• Workshop Goal To form a plan so that we are
  capable of steady-state high-quality physics by
  the end of October shutdown.
• Detector/Computing Systems
• Trigger/Operations/Certifications
• I asked the Physics Group Convenors (present
  incoming) some questions
• What datasets are you using?
• What results and what have you learned about the
  process?
• What concerns vis-à-vis the workshop goals?
• What plans?

3
Contents

• Replies from the Physics Groups
• B-Physics
• Higgs
• NewPhy
• QCD
• Top
• WZ
• Common Elements in Plans Concerns
• Summary

4
B-Physics

• B-physics group is interested in b-quark
  production and decay, CKM-matrix, and
  CP-violation.
• 17 Thesis Students Enlisted.
• Group Datasets
• A MuonJet certification sample of 100,000
  events in Runs 145089 to 149932.
• 100,000 Picked medium dimuons
• 40,000 have M(mm)lt10 GeV/c2.
• 60,000 more have this cut removed.
• All reprocessed with a special version of Reco
  p11 focusing on Tracking (HTF tracking is used).
• ROOT-TUPLES are available on clue-d0.

5
B-Physics Accomplishments

• Observed the J/Psi(mm), Ks(pp-), L(pp-), and
  Y(mm) resonances.
• Using the J/Psi sample, have measured the average
  B-quark lifetime. Its consistent with PDG
  average.
• Updated the MC generator from QQ to EvtGen which
  has better modeling of b-quark angular
  distributions. Also have an event-stripper which
  runs in the MC.
• Analyses for ICHEP (3?)
• Inclusive b cross section
• J/y cross section

6
B-Physics Group J/y sample
early June 2002
Very Recently B to J/Y(mm) K
7
B-Physics Worries

• Tracking and Reconstruction
• B-physics requires very high tracking efficiency
  for high- and low-pT tracks (in jets -htd).
• Standard Reco pT track cutoff is 500 MeV
• Sooo they would like to tag selected events in
  Standard Reco for special processing or
  reprocessing (for scale, see their group
  data-samples -htd).
• The optimal technical solution is to be
  determined.
• SAM Stability (coupled to above?)

8
B-Physics Worries

• Difficulty generating MC samples. Complaints
  about priority for his groups small jobs on the
  farms.
• Physicist power dedicated to the software effort.
• This will comes up again and again. I suspect you
  have already heard it today.

9
B-Physics Plans

• Work on Mass-constrained kinematic fits to
  improve the proper time resolution.
• The group is oriented towards muons and would
  like to get into B-tagging using electrons.
• Interested in lowering the pT cut for leptons in
  the trigger to 1.5 GeV/c
• Doing so will allow D0 somewhere between 10 and
  25 TIMES more J/psi to dimuons and to be more
  than competitive with CDF.
• Requires tracking in the trigger for unprescaled
  samples.

10
Higgs

• Goal is to find the Higgs
• 14 thesis students
• Data Samples are root-tuples on Clued0
• EMjets, mjets, mm, DIEM, multijet
• Reco version p10.15.01 p10.15.02
• Details available at http//www-d0.fnal.gov/suyon
  g/d0_private/Higgs_Streaming.html.
• These are very well documented datasets (htd).

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Higgs Accomplishments

• Higgs Workshops
• May 6th 2 days evenly split between
  fundamentals, such as object ID and triggering,
  and physics talks.
• June 28th 1 day concentrated on analyses in
  progress.
• Many Analyses in progress most advanced go to

12
Higgs Accomplishments

• ICHEP
• bbbarH to all bs (DPF)
• Fermiphobic Higgs to gg (DPF).
• New Higgs to WW to dileptons

13
Higgs Wants/Worries

• Monte Carlo
• Ability for routine rereco on the farms (maybe OK
  now but a long time in coming).
• Routine trigsim on the farms
• Want all of the trigger objects available so they
  can study thresholds.
• A large QCD sample for use with above. A detailed
  request will be forthcoming once trigsim is
  available on the farms.

14
Higgs Wants/Worries

• Data Handling
• How will the group deal with expected large data
  sample (Bs) that they will collect for signal,
  QCD background, B ID development.
• They expect to make heavy use of pick-events to
  form their data samples. But Pick-events is a
  bit of a kludge (This comes up several times).
• Many re-recos of medium-sized data samples.
• B-ID critical for Higgs to bbbar
• the group traded Meena to B ID.

15
Higgs Plans

• Improve on Higgs workshop investigations using D0
  Geant, trigger, Reco
• Inject reality into the MC
• is it that the experts are busy and plan to
  return to this when we reach the nominal
  capability? -htd
• Update the Higgs luminosity reach plot.
• Concentrate on analyses that can be done in Run
  2a with available tools.
• Long Term
• Prepare tools for the main SM channels WH, ZH -gt
  leptonsbbbar

16
New Phenomena

• Susy, Non-SM
• 25 thesis students
• Group Datasets?
• ICHEP results (5?)
• Search for 1st Gen. Leptoquarks
• Large Extra Dimensions
• Gauge Mediated SUSY (ggMET)

M(mm)
MET
ggMET events
egMET events
17
New Phenomena Wants/Worries

• Luminosity Database
• Theyd like it to be easier to use run and
  trigger should be enough (so naïve htd).
• Monte Carlo
• Recod GEANT resolution doesnt match real data.
  Retune OR produce the Run_II generalized analog
  of Run_Is MU_SMEAR. OR
• Rely heavily on FMC.
• Oddities in the Data
• Need to be hunted down by end of October shutdown
  so that fixes can be implemented at the detector
  level (More on this later).

18
New Phenomena Wants/Worries

• Better coordination of the software tools
• Note that the probability of a Root macro working
  on a tuple different from that in which it was
  developed is smaller than desired.

19
New Phenomena Plans

• Revisit the trigger list.
• Changes in capability have outstripped the groups
  efforts at optimization (true for many groups).
• Start to use thumbnails.
• Organize better.
• Large size compels them to form two subgroups in
  order to hear frequently about each analysis.
• New subgroups are SUSY Exotics

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Top

• Interests top production, decay properties,
  mass, non-sm top
• 30 thesis students
• Data Sets
• Root-tuples of
• EMjets, mjets, mm, DIEM, EMm
• Reco version p10.15
• Luminosity tools are provided
• Centralized Activities
• Top group Data samples
• Data quality monitoring
• Triggers for Top
• Monte Carlo for Top
• Analysis Tools (under way)

21
Top Accomplishments

• Data Quality Monitoring
• Produces Good runs for Analysis
• Uses histos generated from roottuples
• Provides feedback to detector/object ID/Farm
  groups reco wrecked the muons recently and the
  top group discovered it.
• Monte Carlo Samples Available
• Trigger Studies
• Large effort on Trigsim of data and M.C.
• The WZ group has, on occasion, borrowed top group
  experts.

22
Top Accomplishments

• Analysis
• concentrated on mjets, ejets, em focusing on
  the W reconstruction.
• Non-W background estimates
• Techniques for isolating top
• Showing _at_ ICHEP
• W(en) jets, Z(mm)jets updates

23
Top Wants/Worries

• Monitoring
• Would like more.
• Would like Trigsim on the Farms as part of
  standard MC chain
• Data Samples
• Would like to remove obsolete/unusable (MC)
  samples in SAM
• Need ability to quickly re-reco samples and
  without losing the luminosity information
• Pick_events loses the luminosity information. Can
  this be changed?
• B-tagging needs help
• Trying for a bigger effort within their group

24
Top Plans

• Continue to provide standard data samples for top
  (e.g. streamed root-tuples, thumbnails,
  top_analyze package)
• Trigger Studies
• Widen scope by looking at more trigger and by
  using trigger info in the data
• Catch up with the new trigger list
• Monte Carlo
• Study generators
• Form subgroups soon in anticipation of stable
  physics running

25
QCD

• Interests Jets Photons
• 4 thesis students
• Datasets 6.3M jet events
• Accomplishments
• Tuple-stripping code
• Contributions to Jet Energy Scale
• Adapting to triggering without large tiles (so
  far) shows

Region was 0 lt h lt 0.8
Jet cross section when2 jets in trigger region
1 jet in trigger region
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QCD Accomplishments

• New for ICHEP
• Low Et Multijets (comparison to Pythia Herwig)
  Run I
• Diffractive W Z Production
• Run II Cross Sections in 5.8 pb-1 for 60 lt
  ET(jet) lt410 GeV and 150 lt M(jj) lt 750
  GeV/c2.

27
QCD Plans Concerns

• Large Tiles when?
• Adopt to the new trigger capability and to the
  changes in the calor. including use of L2 and
  vertex in L3 jet algorithm.
• A new version of jet algorithm the midpoint
  algorithm.
• Adopt to thumbnails will require
• replacing the jet code that was constructed for
  root-tuples.
• They support the idea that root-tuple
  thumbnail.

28
WZ

• Studies properties of the W and Z bosons,
  production and decay measurements, trilinear and
  quadrilinear couplings, some cross-over topics
• 6 thesis students
• Datasets
• Root-tuples produced from WZ Groups Reco-S stream
  containing sorted samples of Isolated m,
  non-isolated m, mm, EMMET, EMEM
• See http//www-d0.fnal.gov/Run2Physics/wz/Public/d
  atabase.html
• Re-SAMED Pick_Events raw data.

29
WZ Accomplishments

• Concentrating on contributing to object ID
  groups
• Muon ID
• Scintillator timing cuts
• Track-matching algorithm
• Isolation studies ( p(fake) gtRun I ).
• Co-rediscovery of Y, U, Z
• Electron ID
• Non-linearity corrections
• Hadronic energy scale
• MET
• Tau ID
• Jet width (all jets skinny like ts)
• Luminosity
• The temporary loan of Marco V. becomes past due
  in just a couple days.

30
WZ Accomplishments

• Lepton ID studies resulted in reduction in
  calorimeter zero suppression from 2.5s to 1.5s
  from pedestal starting with Run 158062. Silke
  Nirmalya.
• ICHEP
• New W mass and W width results from Run I data.
• Combined Run I results with CDF and the world
• W(en) Z(ee) Cross sections and Cross section
  ratio at sqrt(s)1.96 TeV. EB Tuesday 0930

31
WZ Wants/Worries

• The WZ groups ambitions (and potential) doesnt
  match its size
• Expect better documentation
• of physics objects and physics procedures
• Internal description of the data (which
  corrections is it any good?)
• Real Streaming is a
• concern of everybody.
• Theres a session on it here.
• We dont know if we will have the computer
  resources to carry out our plans for creating W
  and Z signal and background samples we need to do
  physics.

32
WZ Plans

• We think its about time to rediscover the W(mn).
• Replace some technical aspects of La Maccina so
  that SAM will do the bookkeeping
• We are abandoning the reco-generated root-tuples
  in favor of Thumbnails for p11
• Need to develop the expertise
• Need to ensure the Thumbnails contain all the
  chunks we require.
• WZ group CVS C code
• Algorithms perform analysis in D0framework on
  thumbnails
• produces WZ_tuple
• W Z objects for monitoring.

33
Common Elements in Plans

• Trigger
• All groups sense they have fallen behind in
  understanding the triggers and making the most of
  the capability
• Data Samples
• Groups plan to migrate to thumbnails ASAP
• Groups will continue to produce their own
  independent data samples
• User-level analysis packages that are CVS
  released official things
• Root-tuples have lead to inefficient progress in
  code development.

34
Common Elements in Concerns Data

• Data Integrity
• Raw Data Quality
• Implement the connection between Significant
  Event Server Coor
• Recorded Data Quality
• Sometimes the readout screws up
• One could imagine a chunk that could contain a
  summary of the summaries from all detectors which
  allows
• user to make a cut on data-integrity in
  thumbnail and root-tuples
• Shpakov will make a proposal in the muon
  detector/algorithm meeting
• Can Lum database info mark the events as they are
  processed in the Farm?
• Good Runs Lists for ALL detectors from respective
  Object ID groups

35
Common Elements in Concerns Computing

• Concern about streaming, data-handling,
  data-set construction
• aggravated by poor communication between the
  physics groups and the computing experts (in CPB?
  Anal. Tools Gp?)
• computing people dont know what we want to do
  and we dont know what is planned or possible
• Not just in streaming and SAM, also in all
  aspects of the D0 analysis chain
• Better Communication

36
Common Elements in Concerns Computing

• A simulation of D0 computing would include models
  of
• Central analysis systems, data handling
  storage, CPU usage, network capability, etc
• Level of sophistication depends on the role of
  the system and its load
• This would help physics groups
• Decide how analyses would be structured and plan
  for time, manpower, and resources
• This would help the computing experts
• Determine where resources would be needed and how
  to adjust priorities for spending
• Build a strong argument in case more resources
  are needed.

37
Summary

• In light of the Workshop Goal
• I reported the Physics Group Conveners (present
  incoming) answers to
• What datasets are you using?
• What results and what have you learned?
• What concerns vis-à-vis the workshop goals?
• What plans?
• I Highlighted some common plans and concerns (and
  some ideas) connected with doing analysis
• Data quality, software effort, computing
  techniques and resources