[G8b_run] g8b question

[Eugene Pasyuk]

Hi Brian,
That's odd. You see a track with no TOF? Time base tracking requires 
TOF. If TOF is missing track won't be reconstructed.
I don't remember if anything like this ever came up when we discussed 
g8b analyses.
I CC: this message to g8b mailing list.

Folks, did anyone noticed anything like this? Particularly, Patrick and 
Chuck, you select the same topologies, with proton and pions.

-Eugene



On 7/19/2011 5:46 PM, Brian Vernarsky wrote:
> Eugene,
>
> I have been looking into the g8b dataset and have come up with an
> interesting problem.  I'm not sure how much you know about g8b, but
> since my normal contacts, Michael Duggar and Phil Cole, are out of
> town I thought I'd see if you had any idea about it.  The problem is
> that a ton of otherwise very good events seem to have no information
> from the TOF scintillators for either the proton or the pi+ and very
> often not for either.  They show normal momenta and photons energies
> and everything is fine except they show that they don't hit any TOF
> paddle, thus they have no pathlength, though they do show an sctime.
> I had worried that it was a problem in my compression scheme, but I
> went back and looked at the original BOS files and the problem is
> there as well, in fact if you look at the EVNT bank at the scstatus it
> shows 0 for the affected particles.  Since this manifested itself in
> looking for omegas I have been worries about p:pi+:pi- events and as I
> said a fair amount of the time both the p and pi+ have scstatus = 0,
> I'm not sure if it is problem that also affects the pi- or other
> particles as I haven't looked into it that far yet.  This is
> particularly worrisome for me because about half of the potential
> omegas that I am looking for have this problem, thus they should be
> thrown out.  But that amounts to about 2+ million omegas being thrown
> away.  I'm not sure if anyone else has seen this, or if it has been a
> problem elsewhere.  I also don't know if there's anything to be done
> about it, perhaps recooking could help.  Thanks for any help.  Hope
> you have been well!
>
> Cheers,
>
> Brian