[d2n-analysis-talk] (fwd) Re: THaHRS Class

[Brad Sawatzky]

Thought this info might be useful to others.

-- Brad

----- Forwarded message from Vincent Sulkosky <vasulk at jlab.org> -----

From: Vincent Sulkosky <vasulk at jlab.org>
Subject: Re: THaHRS Class
To: David Flay <flay at jlab.org>
cc: Brad Sawatzky <brads at jlab.org>


Hi David,

No, the reference plane for timing purposes is S1.  The spectrometer
beta is calculated based on the time-of-flight between S1 and S2 (for
d2n S2 was S2m).

Cheers,
Vince

On Wed, 21 Oct 2009, David Flay wrote:

> Hi Vince,
> 
> I'm going through the analyzer source code to understand how beta is
> constructed, and I came across this comment:
> 
>  // linear regression to:  t = t0 + pathl/(beta*c)
>  //   where t0 is the time of the track at the reference plane (sc_ref).
>  //   t0 and beta are solved for.
> 
> What do they mean by 'reference plane' -- is this the focal plane?
> 
> Thanks,
> 
> Dave

----- End forwarded message -----

-- 
Brad Sawatzky, PhD <brads at jlab.org>  -<>-  Jefferson Lab / Hall C / C111
  Ph: 757-269-5947 -<>- Pager: 757-584-5947 -<>- Fax: 757-269-7848
The most exciting phrase to hear in science, the one that heralds new
  discoveries, is not "Eureka!" but "That's funny..."   -- Isaac Asimov