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Brief description of the L2W Barrel trigger monitoring plots (thanks to Justin Stevens)

Updated on Sun, 2013-05-19 16:56. Originally created by diruzzab on 2013-05-19 16:56.
The L2W algorithms are basically used as a filter to reduce the event yields getting into the st_W data stream from the raw L0 hardware BHT3 and EHT1 triggers.

Here is a brief description of the plots in the L2btowW and L2etowW monitoring pdf that are available at the location:
http://online.star.bnl.gov/L2algo/
these plots are created once the BHT3*L2BW or EHT1*L2EW are included in the trigger mix.

L2 Barrel W Ecal Trigger
The L2btowW algo is very simple, just
1) find a seed tower with ET > 5 GeV and
2) form a 2x2 cluster of towers with ET > 12 GeV around that seed tower.

Description of the L2btowW plots:
Page 2:

upper left is the seed tower ET,
upper right 2x2 cluster ET and lower right ratio of seedET/clusterET *100 (all plots for events accepted by the trigger).
Page 3:
distribution of seed towers with ET > 5 GeV (phi vs eta where each bin is a single tower).
This plot is useful to see "dead" regions with no triggers or identify hot regions where triggers are too frequent.  Ideally this plot is completely uniform.

Page 4-9:
the same as page 3 but binned in barrel tower softID (unique identifier for each tower).  this plot is useful to identify specific towers which are firing much more often than their neighboors.
Page 10:
the same as page 3 but each plot has a different threshold in ET required t increment it, from ET=[10,15] GeV in the upper left to ET=[45,inf] in the lower right.


L2 EndCap W Ecal Trigger
For L2etowW the trigger is much simpler:  just look for a single tower with ET > 10 GeV.

Description of the L2etowW plots:
For the monitoring we have just 2 plots:
top: ET of the most energetic endcap tower in the event for all events
bottom: distribution of most energetic endcap tower in events which satisified the trigger vs tower RDO (unique identifier).

Last update 05/19/2013.

 
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