Difference between revisions of "Constants to Review"

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These are constants whose values need to be revisited
 
These are constants whose values need to be revisited
  
−
=== Digitization-level constants ===
+
=== FCAL ===
  
 
{| class="wikitable"
 
{| class="wikitable"
−
! Det.
 
 
! Description
 
! Description
 
! Variable
 
! Variable
Line 11: Line 10:
 
! Line
 
! Line
 
|-
 
|-
−
| FCAL
 
 
| fADC counts -> physical units  
 
| fADC counts -> physical units  
 
| a_scale
 
| a_scale
Line 18: Line 16:
 
| 53
 
| 53
 
|-
 
|-
−
| FCAL
 
 
| shower profile parameters?
 
| shower profile parameters?
 
|  
 
|  
Line 26: Line 23:
 
|}
 
|}
  
−
'''CDC'''
+
<pre>
 +
void SmearFCAL(s_HDDM_t *hddm_s):
 +
    double t=fcaltruthhit->t + SampleGaussian(200.0E-3); // smear by 200 ps fixed for now 7/2/2009 DL
  
−
a_scale    = 1.0E6/1.3E5
 
  
−
'''FDC'''
+
</pre>
  
−
a_scale      = 2.4E4/1.3E5;  // for cathodes, what about wires?
+
=== CDC ===
  
−
'''FCAL'''
 
  
−
a_scale    = 4.0E1/2.5E5
+
{| class="wikitable"
 +
! Description
 +
! Variable
 +
! Value
 +
! File
 +
! Line
 +
|-
 +
| fADC counts -> physical units
 +
| a_scale
 +
| 1.0E6/1.3E5
 +
| DCDCHit_factory.cc
 +
|
 +
|}
  
−
'''BCAL'''
+
=== FDC ===
  
−
a_scale    = 0.0001; // 100 keV/count (?)
 
  
−
'''TOF'''
+
{| class="wikitable"
 +
! Description
 +
! Variable
 +
! Value
 +
! File
 +
! Line
 +
|-
 +
| fADC counts -> physical units
 +
| a_scale
 +
| 2.4E4/1.3E5
 +
| DFDCHit_factory.cc
 +
|
 +
|}
  
−
a_scale    = 0.2/5.2E5
 
  
−
ADC: hit->sigma_t = 4.0;    // ns (what is the fADC time resolution?) <br />
+
=== BCAL ===
−
TDC: hit->sigma_t = 0.160;    // ns (what is the TOF TDC time resolution?) <br />
+
 
 +
 
 +
{| class="wikitable"
 +
! Description
 +
! Variable
 +
! Value
 +
! File
 +
! Line
 +
|-
 +
| fADC counts -> physical units, 100 keV/count (?)
 +
| a_scale
 +
| 0.0001
 +
| DBCALHit_factory.cc
 +
|
 +
|}
 +
 
 +
=== TOF ===
 +
 
 +
 
 +
{| class="wikitable"
 +
! 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?
 
t0 offset for fADC?
  
−
'''Start Counter'''
+
=== Start Counter ===
  
−
a_scale    = 2.0E-2/5.2E-5
 
  
−
ADC: hit->sigma_t = 4.0;    // ns (what is the fADC time resolution?) <br />
+
{| class="wikitable"
−
TDC: hit->sigma_t = 0.160;    // ns (what is the TOF TDC time resolution?) <br />
+
! Description
 +
! Variable
 +
! Value
 +
! File
 +
! Line
 +
|-
 +
| fADC counts -> physical units
 +
| a_scale
 +
| 2.0E-2/5.2E-5
 +
| DSCHit_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?
 
t0 offset for fADC?
 +
 +
  
 
=== Reconstruction constants ===
 
=== Reconstruction constants ===
Line 95: Line 183:
 
</pre>
 
</pre>
  
−
 
−
'''FCAL'''
 
−
 
−
Various constants in DFCALCluster::shower_profile()
 
  
 
'''BCAL'''
 
'''BCAL'''
Line 144: Line 228:
 
   loading timewalk parameters from CCDB
 
   loading timewalk parameters from CCDB
 
   
 
   
−
</pre>
 
−
 
−
===mcsmear===
 
−
 
−
<pre>
 
−
void SmearFCAL(s_HDDM_t *hddm_s):
 
−
    double t=fcaltruthhit->t + SampleGaussian(200.0E-3); // smear by 200 ps fixed for now 7/2/2009 DL
 
−
 
−
 
 
</pre>
 
</pre>

Revision as of 18:38, 2 June 2014

These are constants whose values need to be revisited

FCAL

Description Variable Value File Line
fADC counts -> physical units a_scale 1.0E6/1.3E5 DFCALHit_factory.cc 53
shower profile parameters? DFCALCluster shower_profile() 
void SmearFCAL(s_HDDM_t *hddm_s):
    double t=fcaltruthhit->t + SampleGaussian(200.0E-3); // smear by 200 ps fixed for now 7/2/2009 DL

CDC

Description Variable Value File Line
fADC counts -> physical units a_scale 1.0E6/1.3E5 DCDCHit_factory.cc

FDC

Description Variable Value File Line
fADC counts -> physical units a_scale 2.4E4/1.3E5 DFDCHit_factory.cc


BCAL

Description Variable Value File Line
fADC counts -> physical units, 100 keV/count (?) a_scale 0.0001 DBCALHit_factory.cc

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
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?


Reconstruction constants

CDC/DCDCTrackHit_factory.h

w_eff=29.5e-9; gas_gain=1e5; hit->dist = hit->tdrift*55.0E-4; // Use number hardwired in simulation for now 

ring/straw counting starts at 1

FDC

FDC/DFDCGeometry.h has a bunch of constants that need to be reconciled with HDGeant/hitFDC.c 

//----- 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 */
//------------------------------------------------


BCAL 

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;

In DBCALPoint::DBCALPoint()
  estimates of m_sig_z

In DBCALShower_factory_IU::DBCALShower_factory_IU()
  energy calibration parameters

In DBCALUnifiedHit_factory::brun()
  loading timewalk parameters from CCDB
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