Spill-On Gate Parameters

To allow for the best separation between cosmics and beam related events one needs distinguish between Spill-On and Spill-Off. This can be achieved with a cut on the first event scaler (ECH_01). This scaler counted a 100 kHz clock and allows to determine the time of each event relative to the `begin of extraction' signal of SIS.

The extraction profile varied during the experiment, both the delay between `begin of extraction' and the first extracted particles as well as the duration of the spill. Thus, the Spill-On Gate cut will be run dependent.

The Spill-On gate values were determined run-by-run from the spill time distribution of the recorded events. This distribution shows a constant background due to cosmics triggers and a beam related component. The Spill-On time interval was defined as the time where the trigger rate was more than 10% above the cosmics level.

All Spill-On gate values are stored in a single file with the format 

 URN       begin         end
which reads like 
4013           0  2147483647
4014           0  2147483647
...
1036           0  2147483647
4036           0  2147483647
4037       76500      287500
4038       77500      290500
4039       74500      297500
4040       86500      281500
An interval of (0,2147483647) denotes either a non-physics, and empty or an otherwise bad run.

Notes:

  1. this dataset has been determined by J. Lukasik
  2. File created in 95% by /u/lukasik/tape/ech/set_thr.C ROOT macro.
  3. 58 runs needed manual correction (by IBR).
  4. Runs 4045-4047 (Au+Au @ 15 MeV/n) have "strange" spills.

Web access

The data is available under spillgate.dat.

GSI local access

The file is accessible from the Linux system under 
    /d/kp3/bck/s185/spillgate/spillgate.dat

INDRA Calibration data

Data by J. Lukasik, Web by Walter F.J. Müller
Last modified: Thu Jun 17 18:02:11 CEST 1999