GMC Output¶

Data Format¶

The data for the e906 experiment, both simulated and real, is stored in a MySQL database. Currently, the GMC output is stored on the seaquel.physics.illinois.edu server. This server can be accessed with MySQL workbench, which can be installed on Windows, Mac, or Linux. You can also find other MySQL interfaces on the internet if you find workbench unsuitable for your needs. There are also libraries for interfacing with MySQL for almost any programming language.

All values have units of GeV, cm, or radians where appropriate.

Output Tables¶

mRun¶

The mRun table includes all the relevant settings for the run.

Name	Variable type	Description
runID	INT	The run number
gitHash	STRING	This string can be cross referenced with the git hashes in the repository to know the version used. However, using the GMC Versions page and the M### part of the production name is simpler.
seed	INT	The random number seed.
eventsThrown	INT	Attempted number of events in the run. This includes attempts at generating dimuons that fail at the generator level due to physical impossibility
eventsThrownPhysical	INT	Dimuon generator only. Number of events in the run. This includes dimuons that fail the acceptance cut but not dimuons that fail due to physical impossibility
beamMomentum	DOUBLE	Beam momentum
beamCurrent	DOUBLE	Protons/sec of the incoming beam
APA	DOUBLE	Output for debugging, will likely be removed
asciiFieldMap	BOOL	1 means the magnetic field was loaded from ascii files, 0 if loaded from MySQL
generator	STRING	dimuon or gun. What type of particle generator was used
dimuonSource	STRING	Dimuon generator only. If a dimuon generator, gives what type of dimuons were generated. Drell-Yan, JPsi, or Psi'
eventPos	STRING	Dimuon generator only. target, dump, upstream, or all. Gives the location dimuons were generated
dimuonRepeat	INT	Dimuon generator only. If more than one, multiple dimuons are generated with the exact same starting kinematics.
x1Min	DOUBLE	Dimuon generator only. Minimum value of x for the beam
x1Min	DOUBLE	Dimuon generator only. Maximum value of x for the beam
x2Min	DOUBLE	Dimuon generator only. Minimum value of x for the target
x2Min	DOUBLE	Dimuon generator only. Miaximum value of x for the target
xFMin	DOUBLE	Dimuon generator only. Minimum value of Feynmann x
xFMin	DOUBLE	Dimuon generator only. Miaximum value of Feynmann x
massMin	DOUBLE	Dimuon generator only. Minimum value of x for the dimuon mass
massMin	DOUBLE	Dimuon generator only. Maximum value of x for the dimuon mass
cosThetaMin	DOUBLE	Dimuon generator only. Minimum value of cos(theta_mu)
cosThetaMax	DOUBLE	Dimuon generator only. Maximum value of cos(theta_mu)
recordMethod	STRING	hits means events without hits are not recorded, energy means all particles above a certain energy are recorded, all means everything is recorded, and dimuonFull means only dimuons where both muons make it to the back are recorded.
fmagStrength	DOUBLE	A number that multiplies the values in the magnetic field map for fmag
kmagStrength	DOUBLE	A number that multiplies the values in the magnetic field map for kmag
pythiaShower	BOOL	Toggle for Pythia generator. Turns QCD shower simulation on/off. Field not included for non pythia generators
geometrySchema	STRING	The name of the MySQL schema used for the shape, material, and position of objects in the experiment
magnetSchema	STRING	The name of the MySQL schema where one gets the magnetic field map, IF magFromAscii is false
target	INT	The same integer used in data to identify targets
timeStart	STRING	Date and time the run started
timeStop	STRING	Date and time the run finished

Spill¶

Intended to mimic the Spill table in data. Most of the entries don't correspond to anything in the Monte Carlo, they are just there in case a program that runs on both data and Monte Carlo reads in those numbers.

Event¶

Name	Variable type	Description
eventID	INT	Index for events. Incremented by one each event
codaEventID	INT	Included to mimic data
runID	INT	The run number
spillID	INT	Index for spills. Incremented by one each spill
MATRIX1	BOOL	1 if the hits matched a pattern for the matrix 1 trigger
MATRIX1	BOOL	1 if the hits matched a pattern for the matrix 2 trigger
MATRIX1	BOOL	1 if the hits matched a pattern for the matrix 3 trigger
MATRIX1	BOOL	1 if the hits matched a pattern for the matrix 4 trigger
MATRIX1	BOOL	1 if the hits matched a pattern for the matrix 5 trigger
NIM1	BOOL	1 if the hits matched a pattern for the nim 1 trigger
NIM2	BOOL	1 if the hits matched a pattern for the nim 2 trigger
NIM3	BOOL	1 if the hits matched a pattern for the nim 3 trigger
NIM4	BOOL	1 if the hits matched a pattern for the nim 4 trigger
NIM5	BOOL	1 if the hits matched a pattern for the nim 5 trigger
dataQuality	INT	Not currently filled, included to match data table
vmeTime	INT	Not currently filled, included to match data table

mDimuon¶

Only available in dimuon productions.

Name	Variable type	Description
runID	INT	The run number
spillID	INT	Index for spills. Incremented by one each spill
eventID	INT	Index for events. Incremented by one each event
mTrackID1	INT	Track index for the positive muon. Used to be trackID1 before version 1012
mTrackID2	INT	Track index for the negative muon. Used to be trackID1 before version 1012
mass	DOUBLE	Invariant mass of the dimuon
xF	DOUBLE	Feynmann x for the collision
xB	DOUBLE	Bjorken x for the incident parton
xT	DOUBLE	Bjorken x for the target parton
dx	DOUBLE	x coordinate of dimuon origin
dy	DOUBLE	y coordinate of dimuon origin
dz	DOUBLE	z coordinate of dimuon origin
dpx	DOUBLE	Initial x momentum of the dimuon
dpy	DOUBLE	Initial y momentum of the dimuon
dpz	DOUBLE	Initial z momentum of the dimuon
phi_gam	DOUBLE	Phi of virtual photon, in xy plane
phi_mu	DOUBLE	Phi of mu+, Collins-Soper frame
theta_mu	DOUBLE	Theta of mu+, Collins-Soper frame
sigWeight	DOUBLE	How likely this event is, according to the cross-section
acceptDriftAll	BOOL	1 if both muons hit drift chambers in all 4 stations. This includes prop tubes
acceptHodoAll	BOOL	1 if both muons hit the trigger hodoscopes in all 4 stations

mGun¶

Only available in gun productions.

Name	Variable type	Description
runID	INT	The run number. Equal to the random number seed for Monte Carlo runs
spillID	INT	Index for spills. Incremented by one each spill
eventID	INT	Index for events. Incremented by one each event
bucketSize	INT	How many protons were generated for this event

mTrack¶

Name	Variable type	Description
mTrackID	INT	Index for tracks. Incremented by one for each new track. Used to be trackID before version 1012
runID	INT	The run number. Equal to the random number seed for Monte Carlo runs
spillID	INT	Index for spills. Incremented by one each spill
eventID	INT	Index for events. Incremented by one each event
parentID	INT	Index of the parent track for this particle
particleID	INT	LUND particle code
parentParticleID	INT	LUND particle code for the parent particle
x0	DOUBLE	x coordinate of track origin
y0	DOUBLE	y coordinate of track origin
z0	DOUBLE	z coordinate of track origin
xf	DOUBLE	x coordinate of track end
yf	DOUBLE	y coordinate of track end
zf	DOUBLE	z coordinate of track end
px0	DOUBLE	initial x momentum
py0	DOUBLE	initial y momentum
pz0	DOUBLE	initial z momentum
pxf	DOUBLE	final x momentum
pyf	DOUBLE	final y momentum
pzf	DOUBLE	final z momentum
x3	DOUBLE	x coordinate of track near station 3
y3	DOUBLE	y coordinate of track near station 3
z3	DOUBLE	z coordinate of track near station 3
px3	DOUBLE	x momentum of track near station 3
py3	DOUBLE	y momentum of track near station 3
pz3	DOUBLE	z momentum of track near station 3
x1	DOUBLE	x coordinate of track near station 1
y1	DOUBLE	y coordinate of track near station 1
z1	DOUBLE	z coordinate of track near station 1
px1	DOUBLE	x momentum of track near station 1
py1	DOUBLE	y momentum of track near station 1
pz1	DOUBLE	z momentum of track near station 1
charge	INT	Charge of particle
creationProcess	STRING	How particle was created, i.e. e+ e- annihilation, etc.
hitHodo1	BOOL	true if the track hit H1x
hitHodo2	BOOL	true if the track hit H2x
hitHodo3	BOOL	true if the track hit H3x
hitHodo4	BOOL	true if the track hit H4x
hitDrift1	BOOL	true if the track hit D1
hitDrift2	BOOL	true if the track hit D2
hitDrift3	BOOL	true if the track hit D3
hitDrift4	BOOL	true if the track hit the prop tubes
protonID	INT	trackID of the initial proton that generated this particle. Gun generator only

mHit¶

Column Name	Variable Type	Description
mHitID	INT	Index for digitized hits
hitID	INT	reference to the hit in the Hit table that results from this hit. May be NULL with detector inefficiencies.
runID	INT	The run number
spillID	INT	Index for spills. Incremented by one each spill
eventID	INT	reference to the event in Event table this wire hit was calculated from
mTrackID	INT	reference to the track in mTrack table this wire hit was calculated from
detectorName	STRING	Name of the detector that was hit
elementID	INT	wire number or hodoscope paddle hit
rocID	INT	rocID the detectorName, elementID maps to
boardID	INT	boardID the detectorName, elementID maps to
channelID	INT	channelID the detectorName, elementID maps to
particleID	INT	LUND particle code
driftDistance	DOUBLE	Drift distance
driftTime	DOUBLE	Estimated drift time in microseconds, derived from drift distance according to our RT curves
tdcTime	DOUBLE	Estimate of the tdcTime such a hit would generate in our electronics
hx	DOUBLE	x position of hit
hy	DOUBLE	y position of hit
hz	DOUBLE	z position of hit
hpx	DOUBLE	x momentum of hit
hpy	DOUBLE	y momentum of hit
hpz	DOUBLE	z momentum of hit

Hit¶

This table is supposed to mimic the Hit table from data. The Hit table is produced from the mHit table, tossing out hits that miss the sensitive area of the detector, or randomly according to the inefficieny value in the Planes table. Extra hits might also be added if a source of noise is added to GMC.

mNoiseHit¶

This table links the mHit table and the Hit table.

Column Name	Variable Type	Description
mHitID	INT	reference to an entry in the mHit table
hitID	INT	reference to an entry in the Hit table
type	STRING	Explains the origin of the Hit in the Hit table, or why a Hit entry was not produced from an mHit entry

Proper Weighting¶

This section describes the methods of normalizing a set of GMC events to get the rate in Hz unit. Written by Kenichi, confirmed by BZ, as of June 15, 2013.

Gun Mode¶

First add up all hits to get a yield in a certain condition (like detector area, mass range, pT range, etc). Then multiply the yield by

[N of protons per second] / [N of protons fired]

N of protons per second is the beamCurrent field in mRun, and is usually 2e12. N of protons fired is the sum of the bucketSize field for all entries in the mGun table. This returns the rate in Hz of all hits meeting this condition.

Dimuon Mode¶

First sum up the sigWeight in the mDimuon table for all the entries that match the kinematics you are looking at. Then divide the weighted yield by the number of generated events, which is the sum of the eventsThrown field in the mRun table. This will return a a rate in Hz, dimuons per second. Note that you must divide by the number of generated events, not accepted events. Even without acceptance cuts the number of rows in the mDimuon table will fall short of the number of events thrown due to physically impossible dimuons. This rate in Hz depends on the beamCurrent setting in the mRun table which affects the weights of the dimuons. To get it from dimuons per second to dimuons per proton you can divide the dimuons per second number by the beamCurrent entry in the mRun table. The beamCurrent entry should be the same for every run unless someone produced a really weird Monte Carlo.