MC Samples¶
Identifying MC Samples¶
MC samples are identified according to serveral criteria:
Data type: typically corresponding to a year of data-taking (e.g.
2018)Simulation conditions: encapsulates the beam conditions and event generator (e.g.
Beam6500GeV-2018-MagUp-Nu1.6-25ns-Pythia8)Processing pass: information about the applications used to produce the sample (e.g.
Sim09l/Trig0x617d18a4/Reco18/Turbo05-WithTurcal/Stripping34NoPrescalingFlagged)Event type: an identifier of the simulated physics processes (e.g.
11296029)File type: the format of the data (e.g.
ALLSTREAMS.DST)
All of these are found in the bookkeeping path of the sample.
Finding MC Samples¶
To find existing simulation samples, look in the LHCb bookkeeping. See also the Starterkit lesson on finding data.
Alternatively, the dirac-bookkeeping-decays-path command from LHCbDIRAC will list all samples for a given event type, along with the DB tags, number of files, number of events and prod ID.
$ lb-dirac dirac-bookkeeping-decays-path 11296029
/MC/2018/Beam6500GeV-2018-MagUp-Nu1.6-25ns-Pythia8/Sim09l/Trig0x617d18a4/Reco18/Turbo05-WithTurcal/Stripping34NoPrescalingFlagged/11296029/ALLSTREAMS.DST dddb-20170721-3 sim-20190430-vc-mu100 406 1007097 184085
/MC/2018/Beam6500GeV-2018-MagDown-Nu1.6-25ns-Pythia8/Sim09l/Trig0x617d18a4/Reco18/Turbo05-WithTurcal/Stripping34NoPrescalingFlagged/11296029/ALLSTREAMS.DST dddb-20170721-3 sim-20190430-vc-md100 398 1001502 184087
/MC/2017/Beam6500GeV-2017-MagUp-Nu1.6-25ns-Pythia8/Sim09l/Trig0x62661709/Reco17/Turbo04a-WithTurcal/Stripping29r2NoPrescalingFlagged/11296029/ALLSTREAMS.DST dddb-20170721-3 sim-20190430-1-vc-mu100 405 1009519 185186
/MC/2017/Beam6500GeV-2017-MagDown-Nu1.6-25ns-Pythia8/Sim09l/Trig0x62661709/Reco17/Turbo04a-WithTurcal/Stripping29r2NoPrescalingFlagged/11296029/ALLSTREAMS.DST dddb-20170721-3 sim-20190430-1-vc-md100 403 1006692 185194
/MC/2016/Beam6500GeV-2016-MagUp-Nu1.6-25ns-Pythia8/Sim09l/Trig0x6139160F/Reco16/Turbo03a/Stripping28r2NoPrescalingFlagged/11296029/ALLSTREAMS.DST dddb-20170721-3 sim-20170721-2-vc-mu100 399 1001775 185242
/MC/2016/Beam6500GeV-2016-MagDown-Nu1.6-25ns-Pythia8/Sim09l/Trig0x6139160F/Reco16/Turbo03a/Stripping28r2NoPrescalingFlagged/11296029/ALLSTREAMS.DST dddb-20170721-3 sim-20170721-2-vc-md100 401 1001213 185246
/MC/2012/Beam4000GeV-2012-MagUp-Nu2.5-Pythia8/Sim09l/Trig0x409f0045/Reco14c/Stripping21r0p1NoPrescalingFlagged/11296029/ALLSTREAMS.DST dddb-20170721-2 sim-20160321-2-vc-mu100 379 1000751 185394
/MC/2012/Beam4000GeV-2012-MagDown-Nu2.5-Pythia8/Sim09l/Trig0x409f0045/Reco14c/Stripping21r0p1NoPrescalingFlagged/11296029/ALLSTREAMS.DST dddb-20170721-2 sim-20160321-2-vc-md100 379 1005074 185402
/MC/2011/Beam3500GeV-2011-MagUp-Nu2-Pythia8/Sim09l/Trig0x40760037/Reco14c/Stripping21r1p1NoPrescalingFlagged/11296029/ALLSTREAMS.DST dddb-20170721-1 sim-20160614-1-vc-mu100 171 504206 185652
/MC/2011/Beam3500GeV-2011-MagDown-Nu2-Pythia8/Sim09l/Trig0x40760037/Reco14c/Stripping21r1p1NoPrescalingFlagged/11296029/ALLSTREAMS.DST dddb-20170721-1 sim-20160614-1-vc-md100 184 549397 185660
/MC/2015/Beam6500GeV-2015-MagUp-Nu1.6-25ns-Pythia8/Sim09m/Trig0x411400a2/Reco15a/Turbo02/Stripping24r2NoPrescalingFlagged/11296029/ALLSTREAMS.DST dddb-20170721-3 sim-20161124-vc-mu100 211 521899 193984
/MC/2015/Beam6500GeV-2015-MagDown-Nu1.6-25ns-Pythia8/Sim09m/Trig0x411400a2/Reco15a/Turbo02/Stripping24r2NoPrescalingFlagged/11296029/ALLSTREAMS.DST dddb-20170721-3 sim-20161124-vc-md100 208 525549 193992
Requesting new MC Samples¶
Contact the MC liaison of your Physics Working Group to request a new sample. The necessary information to make a request includes:
Event type(s)
Event generator, collision type and (if applicable) fast simulation technique (e.g. Pythia8 proton-proton ReDecay)
Number of events per magnet polarity per year
Output format: usually either MDST or DST
Any changes to the default processing pass (e.g. a different Stripping version, different TCK, or filtering script)
Each request must be approved by the convenors of your Physics Working Group before production can start. If the number of events is above certain limits, approval must also come from the Physics Planning Group (PPG). For particularly large requests, they may ask for measures to be taken to reduce CPU or disk usage, such as fast simulation or filtering.
Finding the right event type¶
You can browse the dkfiles/ directory in the DecFiles repository to find the right Decay File for your desired physics process.
The filenames generally describe particle decays and extra options related to the generator.
At the top of the file will be a line starting with # EventType: that specifies the 8-digit number needed when making a request.
Adding a new event type¶
A new event type can be added by writing an EvtGen Decay File and adding it to the DecFiles package.
See the contribution guide in CONTRIBUTING.md in the DecFiles repository.
Creating a request¶
Note
For more detailed information see Instructions for liaisons
The overall procedure is similar to that of Analysis Productions: requests are specified in YAML and committed to a branch in the submission repository on GitLab. Automatic test productions are submitted by the CI, and once the branch is merged, the full requests are submitted.
For straightforward requests that don’t require expert options:
create a new branch in the submission repository,
add a new directory containing your Stage 0 YAML file(s),
commit and push your changes,
create a Merge Request (MR) targeting the
mainbranch,once the pipeline succeeds and approval is given from the MC liaison for the WG, the MR can be merged, which will trigger the submission of the full request.
More advanced requests can require different kinds of YAML file and approval from Simulation experts before merging. For filtered requests, the filtering options files must exist in the appropriate WGConfig data package (see FilteredSimulationProduction) and while support for stripping-filtering exists in the Stage0 format, the WG liaison can clone the Template for Filtered MC Requests on Jira to ask for the request to be set up.