Overall Goals for the Experiment: the
Next Six Months
Introduction
Our aim is to set physics-based goals for D0 that will push our performance significantly beyond current levels in time for the winter conferences. Our general goals are to collect a dataset of at least 50pb-1 by the end of 2002 exploiting the new features of our detector, and to use the data to generate physics results for the March 2003 Moriond conference. We will use this “50pb-1” sample to advance analyses in all the physics groups. These overall goals will drive the priorities for data collection and detector operation, triggering, reconstruction, and software development and will improve the coordination between efforts.
Detector Operations
Beginning
October 15, 2002 our target is to operate at 75% average or greater efficiency
(i.e. physics luminosity/delivered luminosity > 0.75) with steady
improvement thereafter. This efficiency should be monitored and reported
weekly. No major changes in hardware, electronics, and firmware will be allowed
unless explicitly authorized by the Run Coordinator. All E823 detector and trigger elements shall be included in the
run and the configuration of the detectors and their operating parameters shall
be stable.
Trigger
The Trigger Board will modify the trigger list and improve the trigger tools to ensure there are no prescales at any luminosity on the triggers we need for the high priority analyses as defined by the Physics Coordinator.
At the same time, the Trigger Board will keep the rate to tape low enough that we can reconstruct in a timely fashion (and re-reconstruct if necessary) all the data taken. Rate guidance will be provided, taking into account the current and future reconstruction capabilities of the Fermilab farm, the requirements of the reconstruction program, and the need to eliminate data backlog by early January 2003.
Reconstruction
We need to ensure that the "50pb-1" sample is processed expeditiously. By mid-October the Fermilab reconstruction farm will have significantly increased capacity. After the new farm nodes are operational, new data should be reconstructed no later than two weeks after collection. Beforehand, current data sets will be processed preferentially to allow for timely evaluation of the data quality. Any data backlog will be eliminated by early January 2003.
Given the current reconstruction program release schedule, p13 will be available for farm processing in November, hence most of the "50pb-1" sample will be processed with p11. We plan to reprocess a streamed subset of the "50pb-1" sample with p13. This requires having L3 streaming available in October, a streaming model with a “reprocessing” or “express” stream defined, a reliable/stable p13 version of reconstruction by the end of November, and enough extra CPU cycles for re-processing (in addition to processing new data as they are being collected).
Analysis
We will use the “50pb-1” sample to advance analyses on all physics topics. Specific goals for each physics group for Moriond 2003 will evolve over the next month. They should aim to emphasize improvement of calibration, reconstruction, analysis tools, and push our capabilities. We currently envision the following:
Top group:
- Demonstrate the existence of top quark in e, m channels, including those with displaced vertex b-tagging of jets, and measure t-tbar production cross section at 1.96 TeV. (Recall that in 1995 we discovered the top quark with a similar amount of data. The production cross section is 35% higher now at 1.96 TeV, and we have much better b-tagging capabilities).
· Show that we can model the data with a combination of top signal, W+jets and QCD background
- Measure the top quark mass
W/Z group:
- Measure the W and Z production cross section in e, m channels
- Demonstrate production of Ws decaying to t
NP group:
- Determine limits on the production of particles generated by a variety of physics beyond the SM (SUSY, LQ, ED…)
Higgs group:
- Measure the W+jets and Z+ jets production cross sections in e, m channels.
QCD group:
· Measure inclusive jet production cross section
- Demonstrate diffractive physics
B group:
- Measure b quark lifetime and the b production cross section
- Demonstrate observation of different B meson exclusive decay modes
Other Considerations
An important outcome of this exercise should be a listing of those areas of detector and software performance requiring improvement.
This document outlines an overall strategy or goal. The specific tactics required to obtain them require development, cooperation, and negotiation.
During this period to prepare for the next extension of D0 capabilities STT commissioning and development of remote farm reconstruction facilities (in order to increase future processing options and capacity), the Monte Carlo, and reconstruction version P14 should continue.
Timeline
|
Week of: |
Action |
|
Sept 23 |
First version of core trigger list (version 9.0) Tracking algorithm recommendations (go into p13) |
|
Sept 30 |
L3 farm expansion online p13 reconstruction is cut |
|
Oct 7 |
Frozen core trigger list in place (version 9.x) Certified IDs for p11 Streaming available at L3 |
|
Oct 14 |
Establish data logging efficiency of 75% Reco farm expansion comes online Initial calorimeter threshold recommendation (goes into p13) |
|
Oct 21 |
Certify jet energy scale for p11 |
|
Oct 28 |
p13 reconstruction available the farm Tracking triggers available |
|
Nov 4 |
|
|
Nov 11 |
|
|
Nov 18 |
|
|
Nov 25 |
Start reprocessing a subset of older data with p13 Thanksgiving |
|
Dec 2 |
|
|
Dec 9 |
|
|
Dec 16 |
|
|
Dec 23 |
Christmas |
|
Dec 30 |
Current scheduled shutdown (Jan 1) End data taking period (Jan 1) |
|
Jan 6 |
Certified IDs for p13 |
|
Jan 13 |
End data processing and reprocessing for sample |
|
Jan 20 |
|
|
Jan 27 |
Physics groups approval of Results for Moriond 2003 |
|
Feb 3 |
|
|
Feb 10 |
|
|
Feb 17 |
EBs approval of Results for Moriond 2003 |
|
Feb 24 |
|
|
Mar 3 |
|