Add new rare charm lines for Lambda_c -> p gamma (->ee)
New HLT2 rare charm decay line Hlt2Charm_LcpToPpG_EmEp for the study of Lambda_c -> p gamma (->ee). It is inspired by the line Hlt2Charm_LcpToPpEmEp.
The Hlt2Charm_LcpToPpG_EmEp line selects a converted photon dielectron pair:
- Ideally: Lower PID_E requirement on the electron to PID_E > 1.0 instead of 3.0, as misidentified gamma -> ee is not very frequent. For now to have a bandwidth test with the strictest selection, cut is: PID_E > 3.0.
- Adds downstream electrons.
- Cut on m(ee) to select converted photons at 50 MeV for LL and 100 MeV for DD.
A new lambda_c maker is created (make_rarecharm_lambdacs2pee_looselambdamass) to have a looser mass range of m(Lambda_c) \pm 150 MeV instead of 50 MeV. This allows for the modelling of the Lambda_c -> p pi0 in data which is distributed bellow the lambda_c mass when it is reconstructed as lambda_c -> p gamma.
The following HLT1 filters have been added:
Hlt1TrackMVADecisionHlt1TwoTrackMVADecisionHlt1TrackElectronMVADecisionHlt1DiElectronLowMass_DisplacedDecisionHlt1DownstreamGammaToEEDecision
On top of htl1 filtering I have also tightened the following cuts in the make_rarecharm_lambdacs2pee_looselambdamass : bpvdira_min=0.99998 (instead of 0.99996) bpvipchi2_max=10 (instead of 25)
I ran test with also a cut on _PAIR_DOCA_MAX_EE following what will be implemented by this MR . I get the following bandwidth estimation with 100000 events (test following the charm hlt2 bandwidth test snippet:
- pid_e > 1: 0.0035604
- pid_e > 2: 0.0027735
- pid_e > 3: 0.0022446.