[Olympus] Acceptance Simulations

[Michael Kohl]

Hi Axel,
thank you.
Now these double ratios look like they were done with the white generator?
However, the latest plot file "tof_gaps.pdf" in my possession for the 
single-polarity ratios still has the large errors at large angles. Could 
you update them, too?
And add a plot for the yields themselves (from which the ratios are 
formed, maybe all four with different colors in one panel, i.e. three 
panels for 0, 1, and 2cm gaps).

Also it would be good for any of the ratios to zoom into the y range to 
1.0 +-10% in order to see the deviations from one in more detail.

So it looks like there are some good washout effects at work, in 
particular if the efficiency structures are smaller than the "washout 
scale", which could likely be of order of the extended target length. What 
would be interesting next is to study along the lines of Stanislav's 
proposal to see what happens when entire TOF bars or combinations of TOF 
bars are less efficient than others. Here, the benefit 
from washing out structures may be less so, because the localized 
efficiency structures would be of similar order like the "washout scale". 
Similarly, this could be the case for inefficient cells in the WC. How 
much bigger are the corrections for single ratios than for the fourfold 
ratios?

The list of things to look at can obviously be extended for many aspects. 
What we shall think about is, and this was requested by J. Mnich, what is 
the best set of measurements other than B+ running that should be done 
toward the end of the OLYMPUS run that can eventually help us verifying 
and tuning the MC, in order to achieve better than 1% systematics 
everywhere.

Thank you,
   Michael



On Tue, 20 Nov 2012, Axel Schmidt wrote:

> Hi Michael,
> 	I'm attaching the plot of the acceptance double ratio with all four configurations as was initially proposed.  One can see that even with gaps in the ToFs, the ratio remains very close to 1.
>
> 	I have done some studies with different magnetic field strengths (all with positive polarity).  None of the results were so different than those at 5000 A, so I did not find them so intriguing.
>
> Cheers,
> Axel
>
>

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