computing

First Calibration using CuCu data

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Runs used: 6013134 (13 Jan) - 6081062 (22 Mar)

The procedure for performing the relative calibration can be divided into 3 steps:

  1. Create a histogram of the pedestal-subtracted ADC values for minimum-ionizing particles in each tower
  2. Identify the working towers (those with a clearly identifiable MIP-peak)
  3. Use the peak of each histogram together with the location of the tower in eta to calculate a new gain
  4. Create new gain tables and rerun the data, this time looking for electrons
  5. Use the electrons to establish an absolute energy scale for each eta-ring

Using Mike's code from the calibration of the 2004 data, an executable was created to run over the 62GeV CuCu data from Run 5, produce the 2400 histograms, and calculate a new gain for each tower. It was necessary to check these histograms by hand to identify the working towers. The output of the executable is available as a 200 page PDF file:

Recalibration Using pp data

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Originally posted 26 September 2005

Catalog query:
input URL="catalog:star.bnl.gov?production=P05if,tpc=1,emc=1,trgsetupname=ppProduction,filename~st_physics,filetype=daq_reco_mudst,storage=NFS" nFiles="all"

note: 3915/4240 = 92.3% of the available towers were able to be used in the calibration. Lists of bad/weird towers in the pp run are available by tower id:
bad_towers_20050914.txt
weirdtowers_20050914.txt

The relative calibration procedure for pp data is identical to the procedure we used to calibrate the barrel with CuCu data (described below). The difference between pp and CuCu lies in the electron calibration. In the pp data we were able to collect enough electrons on the west side to get an absolute calibration. On the east side we used the procedure that we had done for the west side in CuCu. We used a function that goes like 1/sin(theta) to fit the first 17 eta rings, extrapolated this function to the last three eta rings, and calculated the scale factors that we should get in that region. Here is a summary plot comparing the cucu and pp calibrations for the 2005 run:

(2005_comparison.pdf)

Implementation of Tower Isolation Cut

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Originally posted 11 October 2005

Previously we had calibrated the BEMC using data from all triggers. We now have enough data to restrict ourselves to minimum-bias triggers. Additionally, we have implemented a cut that requires the pedestal-subtracted ADC value of neighboring towers to be less than twice the width of the pedestal. This cut does an excellent job of removing background, especially in the high-eta region:

StEmcAssociationMaker

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Introduction

To treat many-particle events (pp and AuAu), we need to know which particle generated which cluster/point before evaluating the reconstructed clusters and points.  StEmcAssoc

Transfers to/from Birmingham

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Introduction
Transfers where either the source or target are on the Birmingham cluster. I am keeping a log of these as they come up. I don't do them too often so it will take a while to accumulate enough data points to discern any patterns…

Embedding

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Update:  New B/EEMC embedding framework from Wei-Ming Zhang currently in peer review

Calibrations Database

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All calibration information is stored in the STAR database.  We have the following tables for BEMC calibrations:
  • For the BTOW and BPRS detectors:
    • St_emcCalib - this table contains absolute gain information for each channel
    • St_emcPed - this table contains pedestal values for each channel
    • St_emcGain - this table contains a gain correction factor vs. time for each channel (not currently used)

Trigger Database

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This database stores all BEMC trigger information such as trigger status, masks and pedestals used to obtain the high tower and patch sum information.  The database is updated online while taking data.  We have the following table formats:

Database

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These pages describe how to use the BEMC database.  There is a browser-based tool that you can use to view any and all BEMC tables available at:

Run 4 BTOW Calibration

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Introduction:

The recalibration of the BEMC towers for Run 4 includes the following improvements:

Run 5 BTOW Calibration

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Introduction

The final BTOW calibration for Run 5 offers the following improvements over previous database calibrations:

Single Spin Asymmetries by Fill

Away-side only

BJP1 (hardware & software & geometric) requirement, only use pions with dR > 1.5

Action Items

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Immediate action items:

Data Management

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The data management section will have information on data transfer and development/consolidation of tools used in STAR for Grid data transfer.

 

Run 6 BTOW Calibration

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Introduction

This is not the final calibration for the 2006 data, but it's a big improvement over what's currently in the DB.  It uses MIPs to set relative gains for the towers in an

Using your Grid CERT to sign or encrypt Emails

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Apart from allowing you to access the Grid, an SSL Client Certificate is imported into the Web browser from which you requested your Grid certificate. This certificate could be used to digtially sign or encrypt Email. For the second, you will need te certificate from the correspondign partner in order to encrypt Emails. To make use of it, folow the below guidance.

GridLeak: Gain Study

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In February 2005, Blair took some special runs with altered TPC gains so we could study the effect on the GridLeak distortion.

GridLeak Studies

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Datasets

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Here we present information about our datasets.

Adding a New Detector to STAR

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The STAR Geometry Model