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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) {
    ...
  }
}

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