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Draft: Charm changes for start of 2025 data-taking

Carlos Eduardo Cocha Toapaxi requested to merge charm_2025_reopt into master

Goals

MR collecting all modifications to HLT2 lines aiming to reduce the bandwidth/rate consumption detailed in #876

Current status

Commit Bandwidth [GB/s] Reduction
Master 1.18590 -
c5b515a1 1.08415 8.5%

Contributing

If you want to contribute to this MR, please open a new MR and target the charm_2025_reopt branch and explain your goals.

All the additions need to be tested locally, including:

  • Impact on the bandwidth and rate: previous and new rates and bandwidths, respectively. This must be tested using the HLT1 filtered (1.3 MHz) mdfs available at /eos/lhcb/wg/rta/WP3/mdfs_hlt1filtered_307586. To do so, it is recommended to use this snippet.
  • In case of the usage of PersistReco, it has to be well justified.
  • (optional) Impact on the throughput: comparing the time with the execution of master with no extra modifications.
  • (optional) Determine efficiencies: if there is simulation already available, it will be interesting to know the efficiencies so we ensure that there is no bug in the selections.

For lines with exclusive retention rate of 0 would be worth it to check the overlap with other lines.

Do not rebase or force-push to this branch without the consent of the liaisons @lpica @aanelli and @cacochat, since this might lead to losses on the changes

Changes

hexaquarks @ipolyako !4302 (merged)

  • replace PID cuts with PROBNN
  • split all lines into RS and WS, put additional prescale of 0.5 of those WS lines with more than 1 decay mode
  • tighten LTIME and removed prescale in Ps/Hs/Hss lines
  • tighten PROBNN and (sum)PT cuts for PsToPpPimPim line (probably 20% of BW)
  • tighten selection on PT and VCHI2 for Ks and Lambda on top of those in standart_particles
  • tighten cuts on (sum)PT and IPCHI2 on all exclusive Hq lines
  • for detached pp and LamP lines: replace full PersistReco with saving only Long(Downstream)Protos and Long(Downstream)Tracks, relax IPCHI2 < 100 cut given that's its only partially reconstructed thing

d0_to_hh mu-tagged modes (and related D0 builders) @fbetti !4456 (merged)

  • increase PID_K cut of kaons from 0 to 2
  • increase MINIPCHI2CUT cut on D0 children from 9 to 20
  • tighten the mass window of D0 from 1715-2015 to 1780-1950 MeV (and similar in CombinationCut)
  • tighten D_END_VZ - B_END_VZ from -3 to -1.2 mm

ccbaryon_to_hyperon_dh @ziyiw @msaur !4490 (merged)

  • Tighten the PT for proton and D-meson
  • Apply lifetime and VDRHO cut on D-meson
  • Add Xim_END_VZ - Omcc/Xicc_END_VZ cut
  • Enlarge the right mass windows of cc-baryons

hyperonTT @sjaimese @ziyiw !4487 (merged)

  • Tighten the cuts for pion from Xi and lambda_tt
  • Tighten the CHI2DOF and DIRA for xicp_to_ximpipi decays
  • Disable three lines for Xim(TTD) with downstream pions/kaons(Xic0ToXimPip_TTD_D, XicpToXimPipPip_TTD_DD, Xic0ToXimPimPipPip_TTD_DDD)

charm_toh0x module @thadaviz !4362 (merged)

  • Add Hlt1 filter
  • Add neutral isolation particles
Edited by Carlos Eduardo Cocha Toapaxi

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