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Empty events (again)
Hi Richard,
This problem with events occasionally showing up with no hits seems
to still be present, albeit at a much lower level. I reported on this a
few weeks ago and promised I'd send you the details needed to reproduce
it. I'm now finally getting around to it.
I have attached a control.in file that exhibits the problem in
events 84, 464, 493, and 532 when run with release-2009-05-27. (Note
that this is release-2009-05-27 as of todays patch, not the original
release-2009-05-27).
I should note that these events show the problem when running it on
Linux. I see the same problem when running on Mac OS X, but for
different run numbers. This behavior is different than when I ran across
this problem originally where the same event seemed to show the problem
on both platforms. I don't know if this is because I'm making a mistake
or something has changed with the random number generators used on the 2
systems. If you don't see the problem for the event numbers I indicated,
just let me know and I'll look a little deeper.
Regards,
-David
--
------------------------------------------------------------------------
David Lawrence Ph.D.
Staff Scientist Office: (757)269-5567 [[[ [ [ [
Jefferson Lab Pager: (757)584-5567 [ [ [ [ [ [
http://www.jlab.org/~davidl davidl@jlab.org [[[ [[ [[ [[[
------------------------------------------------------------------------
c This is the control file for the GEANT simulation. Parameters defined
c in this file control the kind and extent of simulation that is performed.
c The full list of options is given in section BASE-40 of the GEANT manual.
c
c In addition, some new cards have been defined to set up the input source
c for the simulation. Three kinds of simulation runs are available, selected
c by which of the following three "cards" are present below.
c 1. Input from Monte Carlo generator (card INFILE)
c 2. Built-in coherent bremsstrahlung source (card BEAM)
c 3. Built-in single-track event generator (card KINE)
c The order of the list is significant, that is if INFILE is present then the
c BEAM and KINE cards are ignored, otherwise if BEAM is present then KINE is
c ignored. For example, the 3-card sequence:
c INFILE 'phi-1680.hddm'
c SKIP 25
c TRIG 100
c instructs HDGeant to open ./phi-1680.hddm, skip the first 25 events and then
c process the following 100 input events and stop. If the end of the file is
c reached before the event count specified in card TRIG is exhausted then the
c processing will stop at the end of file.
TRIG 1000
cINFILE 'dummy_inputXXX.hddm'
cBEAM 12. 9.
RUNG 9999
c Commenting out the following line will disable simulated hits output.
OUTFILE 'hdgeant.hddm'
c The following card enables single-track generation (for testing).
c For a single-particle gun, set the momentum (GeV/c), direction
c theta,phi (degrees) and vertex position (cm), and for the particle
c type insert the Geant particle type code plus 100 (eg. 101=gamma,
c 103=electron, 107=pi0, 108=pi+, 109=pi-, 114=proton). If you use
c the particle code but do not add 100 then theta,phi are ignored
c and the particle direction is generated randomly over 4pi sr.
c For a listing of the Geant particle types, see the following URL.
c http://wwwasdoc.web.cern.ch/wwwasdoc/geant_html3/node72.html
c The meaning of the arguments to KINE are as follows.
c - particle = GEANT particle type of primary track + 100
c - momentum = initial track momentum, central value (GeV/c)
c - theta = initial track polar angle, central value (degrees)
c - phi = initial track azimuthal angle, central value (degrees)
c - delta_momentum = spread in initial track momentum, full width (GeV/c)
c - delta_theta = spread in initial track polar angle, full width (degrees)
c - delta_phi = spread in initial track azimuthal angle, full width (degrees)
c
c particle momentum theta phi delta_momentum delta_theta delta_phi
KINE 108 0.6 35.0 0. 0.0 0. 360.
c The SCAP card determines the vertex position for the particle gun. It
c supports the following three arguments, all of which default to 0.
c
c vertex_x vertex_y vertex_z
SCAP 0. 0. 65.
c If you specify a non-zero value for vertex_x and/or vertex_y above then
c all tracks will emerge from the given point. If you leave them at zero,
c you have the option of specifying the HALO card which causes the simulation
c to generate events with a transverse profile modeled after the 12 GeV
c electron beam. The argument only argument to HALO is fhalo, the fraction
c of the beam that lies in the halo region surrounding the core gaussian.
c The nominal value taken from CASA technical note JLAB-TN-06-048 is 5e-5.
c This card is only effective for electron beam simulations with gxtwist.
c
c fhalo
HALO 5e-5
c The following lines control the rate (GHz) of background beam photons
c that are overlayed on each event in the simulation, in addition to the
c particles produced by the standard generation mechanism. A value of
c 1.10 corresponds to nominal GlueX running conditions at an intensity of
c 10^7 tagged photons on target per second. To disable the generation of
c random beam background, comment this line out or set the value of BGRATE
c to zero. Background beam photons are generated during the time interval
c given by the BGGATE card, whose two arguments specify the earliest and
c latest times (ns relative to the time of the original photon that caused
c the event) that a random beam photon could produce background hits
c somewhere in the detector. Note that for this to work, the BEAM card
c must be present (see above). This means that background generation is
c disabled when the simulation operates in particle gun mode.
BGRATE 1.10
BGGATE -100. 900.
c The following card seeds the random number generator so it must be unique
c for each run. There are two ways to specify the random see for a run.
c 1. One argument, must be an integer in the range [1,215]
c 2. Two arguments, must be a pair of positive Integer*4 numbers
c In the first case, one of a limited set of prepared starting seeds is
c chosen from a list. These seeds have been certified to produce random
c sequences that do not repeat within the first 10^9 or so random numbers.
c For cases where more choices are needed, the two-argument form gives
c access to a total of 2^62 choices, with no guarantees about closed loops.
RNDM 3 1
c The following line controls the cutoffs for tracking of particles.
c CUTS cutgam cutele cutneu cuthad cutmuo bcute bcutm dcute dcutm ppcutm tofmax
c - cutgam = Cut for gammas (0.001 GeV)
c - cutele = Cut for electrons (0.001 GeV)
c - cutneu = Cut for neutral hadrons (0.01 GeV)
c - cuthad = Cut for charged hadrons (0.01 GeV)
c - cutmuo = Cut for muons (0.01 GeV)
c - bcute = Cut for electron brems. (CUTGAM)
c - bcutm = Cut for muon brems. (CUTGAM)
c - dcute = Cut for electron delta-rays. (10 TeV)
c - dcutm = Cut for muon delta-rays. (10 TeV)
c - ppcutm = Cut for e+e- pairs by muons. (0.01 GeV)
c - tofmax = Time of flight cut (1.E+10 sec)
c - gcuts = 5 user words (0.)
CUTS 1e-4 1e-4 1e-3 1e-3 1e-4
c The following line controls a set of generic flags that are used to
c control aspects of the simulation generally related to debugging.
c For normal debugging runs these should be left at zero (or omitted).
c At present the following functionality is defined (assumes debug on).
c SWIT(2) = 0 turns off trajectory tracing
c = 2 turns on step-by-step trace during tracking (verbose!)
c = 3 turns on trajectory plotting after tracking is done
c = 4 turns on step-by-step plotting during tracking
c SWIT(3) = 1 stores track trajectories for plotting after tracking is done
c SWIT(4) = 0 trace trajectories of all particle types
c = 3 trace only charged particle trajectories
SWIT 0 0 0 0 0 0 0 0 0 0
c The following card enables the GelHad package (from BaBar)
c on/off ecut scale mode thresh
GELH 1 0.2 1.0 4 0.160
c The following card selects the hadronic physics package
c HADR 0 no hadronic interactions
c HADR 1 GHEISHA only (default)
c HADR 2 GHEISHA only, with no generation of secondaries
c HADR 3 FLUKA (with GHEISHA for neutrons below 20MeV)
c HADR 4 FLUKA (with MICAP for neutrons below 20MeV)
HADR 0
c The following cards are needed if optical photons are being
c being generated and tracked in the simulation. The CKOV directive
c enables Cerenkov generation in materials for which the refractive
c index table has been specified. The LABS card enables absorption
c of optical photons. The ABAN directive controls a special feature
c of Geant which allows it to "abandon" tracking of charged particles
c once their remaining range drops below the distance to the next
c discrete interaction or geometric boundary. Particles abandoned
c during tracking are stopped immediately and dump all remaining energy
c where they lie. The remaining energy is dumped in the correct volume
c so this is OK in most cases, but it can cut into the yield of
c Cerenkov photons (eg. in a lead glass calorimeter) at the end of
c a particle track. If this might be important, set ABAN to 0.
MULS 1
LOSS 1
DCAY 0
PAIR 0
COMP 0
PHOT 0
BREM 0
DRAY 0
ANNI 0
ECOH 0
EVAP 0
FISS 0
ABSO 0
ANNH 0
CAPT 0
EINC 0
INHE 0
MUNU 0
PFIS 0
RAYL 0
LABS 0
LREF 0
CKOV 0
REFL 0
REFR 0
SYNC 0
c The following card prevents GEANT tracking code from abandoning the
c tracking of particles near the end of their range, once it determines
c that their fate is just to stop (i.e. electrons and protons). This
c behaviour is normal in most cases, but in the case of Cerenkov light
c generation it leads to an underestimate for the yields.
c ABAN 1 abandon stopping tracks (default)
c ABAN 0 do not abandon stopping tracks
ABAN 0
c The following card sets up the simulation to perform debugging on
c a subset of the simulated events.
c DEBUG first last step
c - first (int) = event number of first event to debug
c - last (int) = event number of last event to debug
c - step (int) = only debug one event every step events
c DEBUG 1 10 1000
c The following card can be used to turn off generation of secondary
c particles in the simulation, ordinarily it should be 0 (or omitted).
NOSECONDARIES 1
c The following card tells the simulation to store particle trajectories
c in the event output stream. This output can be verbose, use with caution.
c The value set here determines the amount of output recorded:
c
c TRAJECTORIES = 0 don't store trajectory info
c TRAJECTORIES = 1 store birth and death points of primary tracks
c TRAJECTORIES = 2 store birth and death points of all particles
c TRAJECTORIES = 3 store full trajectory of primary tracks
c TRAJECTORIES = 4 store full trajectory of primary tracks and birth/death points of secondaries
c TRAJECTORIES = 5 store full trajectory for all particles
c
TRAJECTORIES 3
c The following tracking parameters are defined for each tracking medium
c TMAXFD (REAL) maximum angular deviation due to the magnetic field
c permitted in one step (degrees)
c DEEMAX (REAL) maximum fractional energy loss in one step (0< DEEMAX <=0.1)
c STEMAX (REAL) maximum step permitted (cm)
c STMIN (REAL) minimum value for the maximum step imposed by energy loss,
c multiple scattering, Cerenkov or magnetic field effects (cm)
c Normally they are assigned appropriate values calculated automatically by
c Geant when the geometry is defined, overwriting the values declared by
c the user code in the GSTMED() call. Users who know what they are doing can
c force Geant to instead use the values passed in the arguments to GSTMED()
c by removing the comment in front of the following card. Any parameters with
c zero values are still assigned automatic values even when AUTO is turned off.
cAUTO 0
END