The STAR experiment

In my azimuthal sDCA studies, I observed static and dynamic azimuthal asymmetries in the CuCu200 data. One suggested possible way to avoid this in upcoming heavy ion runs is to see if there are any online scalers which could be used to give feedback to C-AD as to whether backgrounds at STAR are acceptable in terms of TPC ionization distortions. Towards this end, I have begun a study of whether the BBC scalers might be useful in this regard.

It is important to understand some things about the BBC geometry. Ideally, the large outer tiles are closer to the TPC and more likely represent information relevant to what is happening in the TPC. We would most likely want to implement scalers for these in an upcoming heavy ion run. Unfortunately, in the past we have only taken scaler data for the smaller inner tiles, which are at much smaller radii than the TPC. I show below a schematic I have made of the BBC geometry and PMT layout with respect to a view from the west side of the IR (looking east).

I have arranged the following plots similarly to my azimuthal sDCA studies. First, some terminology. I define NRate (normalized rate) to be the rate of a given PMT's scaler divided by the sum of all 16 inner tile PMT scalers. If I did not normalize the rates in this manner, we would primarily see the simple effect that the rates fluctuate with the luminosity, falling off methodically as the fills progress and lose their luminosity. Secondly, because of the arrangement of PMTs in the BBCs, I have excluded those PMTs which cover two tiles. This means I have 8 useful PMTs on the outer ring of small tiles, and 6 in the inner ring.

In the plots below, the first row shows the <NRate> (mean normalized rate) value for each phi bin. In the subsequent rows, I plot NRate-< NRate> versus day (with each phi bin offset) to see what's happening on sub-day time scales, and versus day in a colored 2D graph to see what's happening on larger time scales. There are two sets of plots: the first is all the CuCu200 BBC scaler data I have, and the second is only for days 37-44 (runs 6037039-6044001) to provide more direct comparison with the CuCu200 data in the sDCA studies.

Additional comments below the plots.

CuCu200 (all days I have)

I have data primarily for the RFF running, and just a couple days into the FF running.

 

2005 CuCu 200	Small outer tiles east	Small outer tiles west	Small inner tiles east	Small inner tiles west
<NRate>
NRate - <NRate> vs. day
NRate - <NRate> vs. day

 

CuCu200 (days37-44)

Runs 6037039-6044001.

 

days 37-44	Small outer tiles east	Small outer tiles west	Small inner tiles east	Small inner tiles west
<NRate>
NRate - <NRate> vs. day
NRate - <NRate> vs. day

The outer small east tile scalers show a very strong signal at phi just below pi. This corresponds to the same azimuthal region for which we have seen other signatures of backgrounds. Additionally, visible dynamic fluctuations appear at the same region in phi for the same outer small east tile scalers. Interestingly, the signs are not as strong on the west side. Also, the inner small tile scalers show a smaller static signature, and almost no noticeable dynamic signatures. Another perhaps interesting note is that the <NRate> values are almost identical for the full dataset and for the days 37-44 subset.

The preliminary conclusion is that there is useful information in the BBC scalers, even the small tile scalers, on backgrounds which may affect ionization within the TPC.

 

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Gene Van Buren

This is intended as a practical introduction to mapfiles for admins of new sites to help get the *basics* working and avoid some common problems with grid user management and accounting.

It should be stressed that manually maintaining mapfiles is the most primitive user management technique.  It is not scalable and it has been nearly obsoleted by two factors:

IF

• Your SSH connections are closed from home
• You get disconnected from any nodes without any reasons?
• ... and you are a PuTTY user
• ... or an Uglix SSH client user

This page is for you. If you are another user, use different clients and so on, this page may still be informative and help you stabalize your connection (the same principles apply).

PuTTY users

PuTTY to connect to gateway (from a home connection), you have to

How to generate keys for about every platform ...

A selection of tips on how to log to the RCF
facility. We hope to augment those pages and add
information as user request or need.

The FNAL_FERMIGRID site policy and some documentation can be found here:

http://fermigrid.fnal.gov/policy.html

You must use VOMS proxies (rather than grid certificate proxies) to run at this site.  A brief intro to voms proxies is here:  Introduction to voms proxies for grid cert users

All users with STAR VOMS proxies are mapped to a single user account ("star").

The information in a voms proxy is a superset of the information in a grid certificate proxy. This additional information includes details about the VO of the user. For users, the potential benefit is the possibility to work as a member of multiple VOs with a single DN and have your jobs accounted accordingly. Obtaining a voms-proxy (if all is well configured) is as simple as “voms-proxy-init -voms star” (This is of course for a member of the STAR VO).

Here is an example to illustrate the difference between grid proxies and voms proxies (note that the WARNING and Error lines at the top don’t seem to preclude the use of the voms proxy – the fact is that I don’t know why those appear or what practical implications there are from the underlying cause – I hope to update this info as I learn more):

OFFLINE QA ISSUES

* Subsytem leaders have been asked to reassess QA needs/expectations
-> No responses yet

* Some question as to whether TPC+SVT tracks are separated from TPC-only tracks
 

• Remaining purchases
  • Web server
  • Tape purchase
• AIDE news
• IRMIS progress
  
• QA & other tool interaction with RunLog

Time	Talk	Presenter
14:00	Follow-ups ( 00:20 ) 0 files	All (All)
14:30	SDAS, requirements, current model, path forward ( 00:20 ) 0 files	All (All)
14:50	AOB ( 00:10 ) 0 files	All (All)
15:00	Offline and online QA ( 00:10 ) 0 files	Gene Van Buren & Jerome Lauret (BNL, BNL)