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Slow Control Archive

Updated on Thu, 2008-04-24 15:08. Originally created by jcs on 2008-04-24 15:06.

FTPC Slow Control Archives

 

Pythia estimates of gamma-jet yields

Updated on Mon, 2010-03-15 15:38. Originally created by sowinski on 2008-04-08 11:10.

Comparison of yields for gamma jet

STAR/RCF resource plans

Updated on Fri, 2008-08-22 10:28 by testadmin. Originally created by jeromel on 2008-04-03 11:42.

 

EEmc Gammas via conversion method, improving yield extraction using postshower information

Updated on Fri, 2008-06-06 15:23. Originally created by jwebb on 2008-03-28 14:56.
Abstract:  We have EEmc Gammas via conversion method, relaxing the hadronic veto cut identified a background contribution which appears consistent with neutral hadrons (or charged hadrons which slip through our cuts) initiating a hadronic shower w/in the calorimeter stack.  Such a neutral background is not accounted for in our estimate of the background efficiency.  Thus, the extraction method breaks down.  For this study, we use the postshower response to estimate the fraction of hadron-like vs photon-like backgrounds, and extract a more reliable single photon yield.
 
1.0 Description of the Method
 
Begin by applying the following cuts to the event sample

Cuts:

1. Require candidate to be w/in the EEMC with pT > 5.0 GeV.
2. Isolation cut -- ET / ETR<0.3 > 0.9
3. Charged particle veto -- require sum of all preshower-1 tiles w/in R < 0.3 to be == 0
4. Analyzing cut -- sum preshower-2 tiles w/in R < 0.3 is greater than zero (i.e. at least one tile w/ ADC > 3 sigma + ped
 
Plot the postshower-to-SMD energy ratio of these events.  We see a broad gaussian on top of a much broader background.  The gaussian "photonic" region occurs for relatively little energy in the postshower detector for relatively large SMD energy deposits.  This is the type of signature we expect for electromagetic showers.  It rides on top of a modest background of events, with a tail which extends to large energy deposits in the postshower with little energy showing up in the SMD.  The events in this "hadronic" region are consistent with hadronic showers occuring w/in the endcap.  We fit the distribution to the sum of two gaussians to estimate their relative contributions.
 
For the rest of this discussion, we define D = log(Epost/(Eu+Ev+delta)).
 
n.b. log is ln, i.e. natural logarithm.  As in TMath::Log() ... which of course is undocumented in the root reference guide, and one has to look at the code to find out.  Sheesh.
 
Figure 1 -- Fit to log(Epost/(Eu+Ev+delta)).  The fit is to the sum of two gaussians.  The fit chi2 (conviently left off of the plot) is somewhat poor... 79.47 per 29 dof.  However, this gives us a starting point to estimate the relative fractions of (a) single photons, (b) photonic backgrounds, and (c) hadronic backgrounds.
 

Proposed STAR HBT BUR for energy scan

Updated on Thu, 2008-03-20 14:09. Originally created by lisa on 2008-03-19 23:50.

Attached find a proposed BUR from STAR-HBT for the energy scan runs.  It is focused on azimuthally-sensitive HBT.  It has been updated 20 March 2008.

Low energy run first look

Updated on Wed, 2008-03-19 13:00 by testadmin. Originally created by jeromel on 2008-03-19 11:54.

Reference

Speaker : Lokesh Kumar ( Panjab )


Talk time : 12:35, Duration : 00:15

Discussion post-meeting

Common

Updated on Sat, 2023-07-29 14:16 by marr. Originally created by lbarnby on 2008-03-18 07:00.

STAR Physics Pages of Common Interest

Approval arrangement

Beam Use Request 2009

Updated on Wed, 2008-05-07 15:09. Originally created by dunlop on 2008-03-18 06:15.

Purpose

A collection of documents and guidance for the team writing five-year the Beam Use Request (BUR) begining Run 9.

eta distributions

Updated on Mon, 2008-03-17 11:54. Originally created by jwebb on 2008-03-17 11:54.
eta distributions

isolation distributions

Updated on Mon, 2008-03-17 11:50. Originally created by jwebb on 2008-03-17 11:50.
isolation distributions

pT distribution vs gamma cuts

Updated on Mon, 2008-03-17 11:30. Originally created by jwebb on 2008-03-17 11:30.
pT distribution vs gamma cuts

ntotal-eqn-1

Updated on Fri, 2008-03-14 15:26. Originally created by jwebb on 2008-03-14 15:26.
ntotal-eqn-1

cdev-code-2008

Updated on Mon, 2008-03-17 09:47. Originally created by sowinski on 2008-03-14 11:32.

CDEV is a system from CAD that broadcasts all sorts of information about the beam includeing fill patterns, spin patterns, beam currents and much more.  Jan developed a system to poll this dat

Talks Committee Criteria and Protocols

Updated on Tue, 2020-04-07 10:24 by salur. Originally created by sowinski on 2008-03-11 17:56.

STAR Talks Committee Overview and Advice to Speakers

(Last updated August 2012)

Nessus false positives and errors

Updated on Fri, 2021-08-27 15:44 by mpoat. Originally created by wbetts on 2008-03-11 16:25.

Here are the list of Nessus scan results that are marked as False Positives, Operational Need, Acceptable Risk, etc. 

Pion Peak

Updated on Wed, 2008-03-05 14:33. Originally created by staruser on 2008-03-05 13:40.

To study the pion peak section of the invariant mass distribution I looked at single pion simulations.  The pions were thrown with pt from 2 - 25 GeV/c flat and were reconstructed using the cu

Cuts and Parameters

Updated on Wed, 2008-03-05 08:54. Originally created by staruser on 2008-03-04 14:15.

Here I will detail the some general information about my analysis; topics that aren't substantial enough to warrant their own page but need to be documented.

Invariant Mass Distribution

Updated on Mon, 2008-03-17 15:30. Originally created by staruser on 2008-03-04 13:53.

The two-photon invariant mass distribution can be roughly broken up into four pieces, seen below*.

Fig. 1

QA for AuAuY7 (splitting & merging for id-pion correlations)

Updated on Fri, 2008-03-14 11:18. Originally created by chajecki on 2008-02-28 23:29.

     

Relative Luminosity

Updated on Thu, 2008-02-28 13:48. Originally created by staruser on 2008-02-28 13:48.