sPHENIX tracking discussion

[Gunther M Roland <rolandg AT mit.edu>]

> 
> * Some of the current momentum resolution / upsilon resolution plots look 
> like that program is lost (or never was).    It is possible to produce a 
> figure of (1) charged particle momentum resolution versus p up to 50 GeV, 
> and (2) upsilon 3-state mass resolution for the following equivalent rates: 
> 1 kHz, 10 kHz, 25 kHz, 50 kHz.     At what rate do the effects of degraded 
> resolution  really kick in?

Hi Jamie,

To keep this discussion from going in circles, it would be good to make sure 
we have a common understanding of the "current momentum resolution/upsilon 
resolution". At least from the plots shown at the January collaboration 
meeting by Tony and Hugo the prospects for the Upsilon measurement look 
reasonable (at least for 1S and 2S). Obviously one can't declare victory 
until the TPC calibration chain for static and time-dependent distortions is 
fully developed and validated. But I think we need to be careful about 
understanding what the basis for strong statements like the one in your mail 
are.

Best,

Gunther