SLAC PEP-II
BABAR
SLAC<->RAL
Babar logo
HEPIC E,S & H Databases PDG HEP preprints
Organization Detector Computing Physics Documentation
Personnel Glossary Sitemap Search Hypernews
Workbook Home Introduction Account Setup QuickTour Packages Modules Unwrap page!
Event Information Tcl Commands Editing Compile and Link Run the Job Debugging
Check this page with the
W3C Validator
(More checks...)
Parameters Tcl Files Find Data Batch Analysis ROOT Tutorial

Tag (Nano)-Level Information: Event Parameters

The Tag ("Nano") level of the database contains variables useful for high-level event selection. These variables describe the event as a whole. They do not contain details of the individual candidates (clusters, tracks), except special ones like the highest-energy or highest-momentum candidates.

The variables are calculated by the following 5 modules in the EventTagTools package:

TagStoreCalorInfo Calorimeter Information
TagStoreTrackInfo Track Information
TagStoreEventShape Event Shape variables
TagStorePrimaryVtx Primary Vertex Variables
TagStoreSemileptonic Variables helpful in semi-leptonic analyses

The calculated variables are below in tabular form, with their C++ type, a short description, what frame of reference they are calculated in, and the selection applied to tracks in the calculation.

For information stored in the Nano database regarding particular physics channels, refer to the AWG pages.

At the bottom of this page, you can find examples of the code you can use to access these variables.

TagStoreCalorInfo

Nano-Database
Variable Name
Type Description CMS or LAB Frame Candidate Selection
(see here for a description of the lists used)
eTotal Float Total visible LAB energy of tracks and neutrals in the event (uses the energy() method for both tracks and neutrals; see Kinematic Variables for discussion.) LAB TaggingList and CalorNeutral
eCharShow Float Total LAB energy of Charged Candidates, by using the time-compenent of the associated Emc cluster's four-momentum. LAB TaggingList
eNeutralMag Float Magnitude of the sum of the 3-momentum vectors. The magnitude of the 3-momenta is just the energy (implying zero mass - the photon), with the direction as that from the origin to the center of the cluster. LAB CalorNeutral not overlapping with any candidates in TaggingList
eNeutralCosTh Float Cosine of the polar angle of the sum of the 3-momentum. See eNeutralMag for 3-momentum description. LAB Same as eNeutralMag
eNeutralPhi Float Azimuthal angle of the sum of the 3-momentum. See eNeutralMag for 3-momentum description. LAB Same as eNeutralMag
e1Mag Float Calibrated EMC energy. CMS Highest energy CalorNeutral item not overlapping with any candidate in TaggingList
e1CosTheta Float Cosine of the polar angle of the candidate's 3-momentum. CMS Same as e1Mag
e1Phi Float Azimuthal angle of the candidate's 3-momentum. CMS Same as e1Mag
e2Mag Float Calibrated EMC energy. CMS 2nd highest energy CalorNeutral item not overlapping with any candidate in TaggingList
e2CosTheta Float Cosine of the polar angle of the candidate's 3-momentum. CMS Same as e2Mag
e2Phi Float Azimuthal angle of the candidate's 3-momentum. CMS Same as e2Mag

TagStoreTrackInfo

Quantity Type Description CMS or LAB Frame Candidate Selection
(see here for a description of the lists used)
pTotalMag Float Magnitude of the sum of the 3-momentum vectors LAB TaggingList
pTotalCosTh Float Cosine of the polar angle of the sum of the 3-momentum vectors. LAB TaggingList
pTotalPhi Float Azimuthal angle of the sum of the 3-momentum vectors. LAB TaggingList
pTotalMass Float Magnitude of the sum of the
4-momentum vectors
LAB TaggingList
pTotalScalar Float LAB
p1Mag Float Magnitude of the candidate's 3-momentum. CMS TaggingList, highest momentum candidate
p1CosTheta Float Cosine of the polar angle of the candidate's 3-momentum. CMS same as p1Mag
p1Phi Float Azimuthal angle of the candidate's 3-momentum. CMS same as p1Mag
p1EmcCandEnergy Float Calibrated calorimeter energy associated with the highest momentum charged track. CMS same as p1Mag
p2Mag Float Magnitude of the candidate's 3-momentum. CMS TaggingList, 2nd highest momentum candidate
p2CosTheta Float Cosine of the polar angle of the candidate's 3-momentum. CMS same as p2Mag
p2Phi Float Azimuthal angle of the candidate's 3-momentum. CMS same as p2Mag
p2EmcCandEnergy Float Calibrated calorimeter energy associated with the highest momentum charged track. CMS same as p2Mag
nTracks Int number of entries in the TaggingList list N/A TaggingList
nGoodTrkLoose Int number of entries in the GoodTracksLoose list N/A GoodTracksLoose
nGoodTrkTight Int number of entries in the GoodTracksTight list N/A GoodTracksTight
p1PidHypo Int particle hypothesis:
-1= none
0= electron
1= muon
2= pion
3= kaon
4= proton
N/A same as p1Mag
p2PidHypo Int same as p1PidHypo N/A same as p2Mag
totChargeLoose Int Sum of the candidates charges N/A GoodTracksLoose
totChargeTight Int Sum of the candidates charges N/A GoodTracksTight

TagStoreEventShape

Quantity Type Description CMS or LAB Frame Candidate Selection
(see here for a description of the lists used)
thrustMag
thrustMagAll
Float Magnitude of the Event's Thrust 3-Vector CMS ChargedTracks are used for non-'All';
ChargedTracksAcc and GoodNeutralLooseAcc for 'All'
thrustCosTh
thrustCosThAll
Float Cosine of the polar angle of the Event's Thrust 3-Vector CMS Same as above
thrustPhi
thrustPhiAll
Float Azimuthal angle of the Event's Thrust 3-Vector CMS Same as above
R2
R2All
Float 2nd Fox-Wolfram Moment (divided by the 0th Fox-Wolfram Moment) CMS Same as above
sphericityAll Float Sphericity of the Event CMS ChargedTracksAcc and GoodNeutralLooseAcc

TagStorePrimaryVtx

Quantity Type Description CMS or LAB Frame Candidate Selection
(see here for a description of the lists used)
xPrimaryVtx Float x-coordinate of the event's primary vertex LAB N/A
yPrimaryVtx Float y-coordinate of the event's primary vertex LAB N/A
zPrimaryVtx Float z-coordinate of the event's primary vertex LAB N/A
probPrimaryVtx Float Significance Level of the Chi-Square for the
Primary Vertex Fit
LAB N/A

TagStoreSemileptonic

Quantity Type Description CMS or LAB Frame Candidate Selection
(see here for a description of the lists used)
    The following tags give signed (corresponding to the particles charge) momentum of the named particle. Naming convention is [lepton name] [selection criteria] [1st or 2nd highest momentum particle satisfying criteria] [cms/lab frame]. A value of 0 indicates no track existed in the list.   The lists used are tag versions of the real lists found on the lists page. These are meant to be simpler, more robust selections very similar to the actual selectors.
elecLoose1cm Float See above CMS tagElectronsLoose
elecLoose2cm Float See above CMS tagElectronsLoose
elecTight1cm Float See above CMS tagElectronsTight
elecTight2cm Float See above CMS tagElectronsTight
muonLoose1cm Float See above CMS tagMuonsLoose
muonLoose2cm Float See above CMS tagMuonsLoose
muonTight1cm Float See above CMS tagMuonsTight
muonTight2cm Float See above CMS tagMuonsTight
elecLoose1l Float See above LAB tagElectronsLoose
elecLoose2l Float See above LAB tagElectronsLoose
elecTight1l Float See above LAB tagElectronsTight
elecTight2l Float See above LAB tagElectronsTight
muonLoose1l Float See above LAB tagMuonsLoose
muonLoose2l Float See above LAB tagMuonsLoose
muonTight1l Float See above LAB tagMuonsTight
muonTight2l Float See above LAB tagMuonsTight

Example Code

Here is the code that is needed to get one of these quantities. First, you get the tag of the event. Then, you access a particular type of variable with the member function tag->getXXX(), which takes 2 arguments - first, your variable name, and second, the stored variable's name in quotes.

In your module's event(AbsEvent *anEvent) function:

AbsEventTag* tag = Ifd<AbsEventTag>::get( anEvent );

// boolean example
bool didItPass;

if(tag->getBool(didItPass,"leptLoose1PassedTight") ){ 
  if (didItPass) {
    ...
  }
}

// floating point examples
float totalEnergy;

if(tag->getFloat(totalEnergy,"eTotal") ){ 
  if (totalEnergy > 9.5) {
    ...
  }
}

// integer example
int numTracks;

if(tag->getInt(numTracks,"nTracks") ){ 
  if (numTracks > 4) {
    ...
  }
}



Back to Event Information Page

Send comments to Workbook Team.