Difference between revisions of "Constants to Review"
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In DBCALUnifiedHit_factory::brun():34-119 - Need to revisit timewalk corrections. | In DBCALUnifiedHit_factory::brun():34-119 - Need to revisit timewalk corrections. | ||
| + | |||
| + | Various clusterizing parameters/calculations: | ||
| + | <pre> | ||
| + | DBCALCluster.cc: | ||
| + | |||
| + | // The method below for determining sig_theta works better than the one | ||
| + | // above. sigma_z is determined using errors when reconstructing MC data. | ||
| + | double sigma_z = sqrt(1.394*1.394/m_E + 0.859*0.859); | ||
| + | m_sig_theta = sigma_z*sin(m_theta)*sin(m_theta)/DBCALGeometry::BCALINNERRAD; | ||
| + | |||
| + | DBCALCluster_factory.cc: | ||
| + | |||
| + | In DBCALCluster_factory::evnt(), energy threshold is 5*k_MeV | ||
| + | |||
| + | In DBCALCluster_factory::clusterize() | ||
| + | float seedThresh = 1*k_GeV; | ||
| + | float minSeed = 10*k_MeV; | ||
| + | |||
| + | In DBCALCluster_factory::overlap( const DBCALCluster& highEClust, | ||
| + | const DBCALCluster& lowEClust ) | ||
| + | //deltaPhi_force_merge and delta_z_force_merge were determined by looking | ||
| + | //at the separation of decay photons from pi0's from a pythia sample. | ||
| + | //There are no events where the decay photons have separation | ||
| + | //(delta_phi < 0.2 && delta_z < 25 cm), so in most cases it should be safe | ||
| + | //to merge clusters together if they are so close. | ||
| + | const double deltaPhi_force_merge = 0.1; //radians | ||
| + | const double delta_z_force_merge = 15.0*k_cm; | ||
| + | |||
| + | //A major cause of extra clusters are lower energy hits, which have poor | ||
| + | //z-resolution and so are not properly merged. Treat low energy | ||
| + | //clusters (< 40 MeV) as a special case. Again, hopefully this is only | ||
| + | //a temporary fix until we have a more comprehensive solution. | ||
| + | const double delta_z_force_merge_low_E = 40.0*k_cm; | ||
| + | const double low_E = .04*k_GeV; | ||
| + | |||
| + | </pre> | ||
== TOF == | == TOF == | ||
Revision as of 18:04, 3 June 2014
These are constants whose values need to be revisited
FCAL
| Description | Variable | Value | File | Line/Function |
|---|---|---|---|---|
| fADC counts -> physical units | a_scale | 1.0E6/1.3E5 | DFCALHit_factory.cc | 53 |
| shower profile parameters? | DFCALCluster | shower_profile() | ||
| mcsmear gaussian time resolution (ps) | 200. | mcsmear/smear.cc | 869 |
CDC
| Description | Variable | Value | File | Line | Action to take |
|---|---|---|---|---|---|
| fADC counts -> physical units | a_scale | 1.0E6/1.3E5 | DCDCHit_factory.cc | ||
| Energy conversion factor for dE calc. | w_eff | 29.5E-9 | DCDCTrackHit_factory.cc | 109 | |
| Gain factor for dE calc. | gas_gain | 1.0E5 | DCDCTrackHit_factory.cc | 110 | |
| initial time -> drift conversion | 55.0E-4 | DCDCTrackHit_factory.cc | 113 | Remove |
FDC
| Description | Variable | Value | File | Line |
|---|---|---|---|---|
| fADC counts -> physical units | a_scale | 2.4E4/1.3E5 | DFDCHit_factory.cc | |
| Time range used to cluster cathode hits (ns) | TIME_SLICE | 10 | DFDCCathodeCluster_factory.cc | 10 |
| Energy conversion factor for dE calc. | W_EFF | 30.2e-9 | DFDCPseudo_factory.cc | 26 |
| Gain factor for dE calc. | GAS_GAIN | 8e4 | DFDCPseudo_factory.cc | 27 |
BCAL
| Description | Variable | Value | File | Line |
|---|---|---|---|---|
| fADC counts -> physical units, 100 keV/count (?) | a_scale | 0.0001 | DBCALHit_factory.cc | 38 |
| non-linear shower energy corrections | DBCALShower_factory_IU.cc | 23-46 | ||
| sigma(z) estimation, cm (with TDC info, from NIM article) | m_sig_z | 1.1 / sqrt(E) | DBCALPoint.cc | 96 |
| sigma(z) estimation, cm (without TDC info, from NIM article) | m_sig_z | 30. | DBCALPoint.cc | 104 |
In DBCALUnifiedHit_factory::brun():34-119 - Need to revisit timewalk corrections.
Various clusterizing parameters/calculations:
DBCALCluster.cc:
// The method below for determining sig_theta works better than the one
// above. sigma_z is determined using errors when reconstructing MC data.
double sigma_z = sqrt(1.394*1.394/m_E + 0.859*0.859);
m_sig_theta = sigma_z*sin(m_theta)*sin(m_theta)/DBCALGeometry::BCALINNERRAD;
DBCALCluster_factory.cc:
In DBCALCluster_factory::evnt(), energy threshold is 5*k_MeV
In DBCALCluster_factory::clusterize()
float seedThresh = 1*k_GeV;
float minSeed = 10*k_MeV;
In DBCALCluster_factory::overlap( const DBCALCluster& highEClust,
const DBCALCluster& lowEClust )
//deltaPhi_force_merge and delta_z_force_merge were determined by looking
//at the separation of decay photons from pi0's from a pythia sample.
//There are no events where the decay photons have separation
//(delta_phi < 0.2 && delta_z < 25 cm), so in most cases it should be safe
//to merge clusters together if they are so close.
const double deltaPhi_force_merge = 0.1; //radians
const double delta_z_force_merge = 15.0*k_cm;
//A major cause of extra clusters are lower energy hits, which have poor
//z-resolution and so are not properly merged. Treat low energy
//clusters (< 40 MeV) as a special case. Again, hopefully this is only
//a temporary fix until we have a more comprehensive solution.
const double delta_z_force_merge_low_E = 40.0*k_cm;
const double low_E = .04*k_GeV;
TOF
| Description | Variable | Value | File | Line |
|---|---|---|---|---|
| fADC counts -> physical units | a_scale | 0.2/5.2E5 | DTOFHit_factory.cc | |
| fADC time resolution (ns) | hit->sigma_t | 4.0 | DTOFHit_factory.cc | |
| TDC time resolution (ns) | hit->sigma_t | 0.160 | DTOFHit_factory.cc |
t0 offset for fADC?
Start Counter
| Description | Variable | Value | File | Line |
|---|---|---|---|---|
| fADC counts -> physical units | a_scale | 2.0E-2/5.2E-5 | DSCHit_factory.cc | 36 |
| fADC time resolution (ns) | hit->sigma_t | 4.0 | DSCHit_factory.cc | 37 |
| TDC time resolution (ns) | hit->sigma_t | 0.160 | DSCHit_factory.cc | 38 |
Geometry constants
FDC
FDC/DFDCGeometry.h has a bunch of constants that need to be reconciled with HDGeant/hitFDC.c Note that HDGeant/hitFDC.c actually reads these out of the CCDB (!)
//----- These were cut from HDGeant/hitFDC.c ----- #define DRIFT_SPEED .0055 #define CATHODE_ROT_ANGLE 1.309 // 75 degrees //#define CATHODE_ROT_ANGLE 0.7854 // 45 degrees #define WIRE_DEAD_ZONE_RADIUS 3.2 #define ANODE_CATHODE_SPACING 0.5 #define TWO_HIT_RESOL 250. #define WIRES_PER_PLANE 96 #define WIRE_SPACING 1.0 #define U_OF_WIRE_ZERO (-((WIRES_PER_PLANE-1)*WIRE_SPACING)/2) #define STRIPS_PER_PLANE 192 #define STRIP_SPACING 0.5 #define U_OF_STRIP_ZERO (-((STRIPS_PER_PLANE-1)*STRIP_SPACING)/2) #define STRIP_GAP 0.1 #define MAX_HITS 100 //#define K2 1.15 #define STRIP_NODES 3 #define THRESH_KEV 1. #define THRESH_STRIPS 5. /* mV */ #define ELECTRON_CHARGE 1.6022e-4 /* fC */ //------------------------------------------------
