SLB: Developments towards JuneTS

Description

Improve HLT2 throughput and signal purity by working on selections for "worst" combiners (those that make the most combinations) identified in the SLB trigger.

• Add GEC requirement on nFTClusters < 14000 (limit on the number of SciFi clusters) for hadronic tau lines to reduce combinatorics
• Increase MaxCandidates in Sprucing to avoid reaching the combination limit when doing the isolation
• Change 0.2<OWNPVFDRHO<5.0 to 0.3<OWNPVFDRHO<8.0 (radial flight distance cut from PV) for hadronic tau builder to reduce the multiple candidates without losing efficiency from MC simulation
• Add p_T>1GeV OR ghostprob(\pi_{1})+ghostprob(\pi_{2})+ghostprob(\pi_{3})<0.2 requirement for hadronic tau builder from this study from @amathad
• Add requirement to remove multiple tau candidates from the region close to the z axis: NOT(\eta > 3.8 && p_T < 2500 MeV)
• Add requirement on parent particle for hadronic tau decay OWNPVFDRHO>0.4
• Set proton momentum cut larger than 10 GeV when the PID requirement is applied.
• Apply @mrudolph suggestions to tune baryonic charm builders: Kaons PID_K>2 (before was PID_K>0), protons PID_P>5, (PID_P - PID_K) > 2.0 (before was PID_P>5, (PID_P - PID_K) > 2.0), tightening children MINIPCHI2>6 (before was MINIPCHI2>4), tighten VTXCHI2<4 (before was VTXCHI2<6)
• Further prescale HLT2 MuonDecayInFlight lines from 4% to 2% (Spruce prescale will still be 50%)
• Remove downstream B\to l\gamma lines and retune the LL lines
• Tune B_s\to Ke\nu lines and further prescale background lines
• Add radial distance cut as default to charm builders OWNPVFDRHO>0.3

Expected BW improvement

Measured on 2025 data locally, wrt SPRUCE full stream

Changes	BW	rate	COMMENTS
Central branch (ci-test results)	-5.27%	-8.33%	NOT RELIABLE (BUG ON RADIAL FD CUT)
With !4994 (merged) and !5023 (merged)	-9.3%)	-6.5%	RELIABLE