P. Klabbers, Tower Grouping for Finding e/gamma Candidates , April 21, 2023 1

Grouping of Towers for finding e/Grouping of Towers for finding e/ Candidates Candidates

Grouping of Towers for finding e/Grouping of Towers for finding e/ Candidates Candidates

Grouping the towers to do the electron algorithm in EGWithShare.cc and CableShareRecv.cc

• The towers for each region are placed in an array that is 6x6.

• I use indexes m and k for eta and phi respectively.• Central towers are assigned to indices 1 to 4.

• These are filled with random data with about 25% occupancy. Of these, 6.375% of the time, the veto bit is set.

• The veto bit is set for about 1% of towers with no energy

• Shared data is then copied into the arrays of the neighboring towers, indices are 0 and 5

• To apply the algorithm, I loop over all central towers, looking for maximum ET of the central tower + highest energy neighbor, including the adjacent shared towers

• while applying the TP_LF bit’s preference for the central tower in the case of equal towers

• Also applying isolation criteria (includes corner shared towers)

• The top energy isolated and non-isolated for each region are kept for later sorting

, m

k 00

1

1 2

2

3

3 4

4

5

5

Adjacent shared tower

Corner shared tower

P. Klabbers, Tower Grouping for Finding e/gamma Candidates , April 21, 2023 2

CMS Calorimeter GeometryCMS Calorimeter GeometryCMS Calorimeter GeometryCMS Calorimeter Geometry

EB, EE, HB, HE map to 18 RCT crates

Provide e/ and jet, ET triggers

P. Klabbers, Tower Grouping for Finding e/gamma Candidates , April 21, 2023 3

Trigger MappingTrigger MappingTrigger MappingTrigger Mapping

P. Klabbers, Tower Grouping for Finding e/gamma Candidates , April 21, 2023 4

= 0º is in the direction of the center of the LHC

P. Klabbers, Tower Grouping for Finding e/gamma Candidates , April 21, 2023 5