Add algorithms to filter charged or brem calo clusters
Use existing CaloDigit-Track matching and Brem recovery information to filter calo clusters. First attempt at addressing #484.
With the current implementation, a veto for track-matched clusters is applied when constructing the NeutralBasicParticle
objects, while a veto for Bremsstrahlung-matched clusters is applied in the TwoCaloClusters
selection algorithm (which is the underlying algorithm of Hlt1Pi02GammaGamma
).
Some preliminary results based on the Hlt1Pi02GammaGamma
monitoring line can be found below.
The line is run with no prescaling and without the nPV cut on the upgrade_mc_minbias_scifi_v5_retinacluster_000_v1_newLHCbID.mdf
sample (10k events).
Mass fits are performed on the diphoton mass distrubution using a Gaussian to describe the \pi^0
signal and a power law to describe background.
With the default requirements, 16652
cadidate diphotons are selected, out of which 980 \pm 68
are signal (see fit below).
Removing diclusters for which at least one seed cell has been matched to a track, the number of selected candidates falls to 13140
, out of which 945 \pm 114
are signal (see fit below).
Removing diclusters for which at least one seed cell has been matched to Bremsstrahlung, the number of selected candidates is 14445
, out of which 910 \pm 134
are signal (see fit below).
Finally, applying both vetoes we get 11351
candiates and 922 \pm 59
signal events (see fit below).
Below you can alse find the distribution of vetoed diphotons fitted with background only.
In summary,
Candidates | Variation | S/B | |
---|---|---|---|
Default | 16652 |
- |
(5.9 \pm 0.4)\% |
TM-only | 13140 |
-21.1\% |
(7.2 \pm 0.9)\% |
BM-only | 14445 |
-13.3\% |
(6.3 \pm 0.9)\% |
BM+TM | 11351 |
-31.2\% |
(8.1 \pm 0.5)\% |