Possibilities for Splitter Data

Updated: 23-Mar-04, H.Evans

Background

We are planning to test the L1Cal in situ using real data from the BLS cards with the help of signal Splitters. Saclay has produced four of these cards, which split the EM and H outputs of four TTs each. These cards have been demonstrated to cause no (or at least very small) perturbions to the main BLS. However, the cards are physically large and may not be able to be used to split data from large contiguous regions of the detector.

This split data could be useful for a number of studies, including:

  1. Gaining experience running the system regularly, including readout to L3.
  2. Characterization of noise on the input signals.
  3. Determination of optimal digital filter coefficients using real data.
  4. Studies of the performance of the sliding windows algorithms under realistic conditions.
Some of these studies require many more TTs than we currently have access to with our four splitter cards. We need to decide quickly whether it will be worthwhile to build more of these cards, and, if so, whether a newly designed card would be appropriate.

Possible Options

Data requirements for some of the possible studies we would like to perform are given below.

Unit BLS Channels Required
(eta x phi x EM/H)		 No. ADFs Required No. Local Max
Current Splitter
o 4 of these have been fabricated 		4 x 1 x 2
(= 8)		 1 0
Enough data to find a single local maximum using the jet algorithm 6 x 6 x 2
(= 72)		 4
(unused inputs)		 1
Data for a single SW chip on a TAB
o except for ICR data
o minimal version 		9 x 9 x 2
(= 162)		 9
(unused inputs)		 4 x 4
Data for a single SW chip on a TAB
o except for ICR data
o all ADF chan's populated 		12 x 12 x 2
(= 288)		 9
(all inputs used)		 4 x 4
Single SW chip including ICR data
o minimal version 		9 x 9 x 2
+ 2 x 9 x 2
(= 198)		 12
(unused inputs)		 4 x 4