>
> I think one of the missing parameters of PART is a t_0 time, or "time
> calculated back to the vertex origin." Adding this would allow the
> simulation of out of time tracks.
> Additionally we could consider uncertainties on the x,y,z,px,py,pz,t_0
> quantities.
>
> - Maurik
Regarding the 2 points above, it was my belief that the PART bank would
get information from other banks, like the error matrix for the track,
which could be used in a kinematic fitter, for example. Also,
'time-at-vertex' can come from, say, the HBID bank.
That is why the 'trkid' field is there:
typedef struct {
int pid; /* particle id (GEANT) */
float x; /* x, Vertex position {x,y,z} */
float y; /* y */
float z; /* z */
float e; /* Energy */
float px; /* momentum {x,y,z} */
float py; /* py */
float pz; /* pz */
float q; /* charge */
int trkid; /* track pointer */
float qpid; /* quality factor for the pid */
float qtrk; /* quality factor for the trk */
int flags; /* set of flags defining track (ie, BEAM) */
} part_t;
to provide the pointer back to other banks.
One question I have is why the charge is always defined as a float?
It's the same in HBTR!!!!
--
Regards,
D. P. Weygand
Thomas Jefferson National Accelerator Facility
Phone: (757) 269-5926
FAX: (757) 269-5800
weygand@cebaf.gov
http://www.sura.org/~weygand