[b1_ana] draft proposal v02

[Dustin Keller]

ok thanks, I agree, just not sure what to put in for charge stability yet
it maybe the leading component.

dustin

On Sun, 5 May 2013, Jian-ping Chen wrote:

> Dustin,
>
> For the study of asymmetry changes due to drift in charge measurement and
> detector efficiency, the transversity experience can only be used for
> detectors, not for charge, since the conditions for charge/current 
> measurement
> are completely different (10 uA vs 100 nA). So we need information from 
> g2p/GEp
> to say anything about charge/current.
>
> For HRS detector drift during transversity , we measured detector response
> (normalized yield for same condition) over long period and see little change 
> (<1%).
> The measurements were usually limited to about 1% precision.
> Not worrying about fluctuations (which does not contribute to overall drift), 
> this
> means that for short time (20 minutes period when we did target spin flip),
> the detector drift should be less than 1%*20minte/3 months and significantly
> less than 10^-3. We just took it as 10^-3 to be conservative.The total 
> contribution to
> our false asymmetry is 10^-3/sqrt(N_pairs)  < 10^-4 (since we have more than 
> 100 pairs).
> This is also confirmed from checking false asymmetries.
>
> To translate to our proposal, if we can keep detector response to be stable
> at 1% in 3 months, then in 12 hours, stability should again be better than 
> 10^-3,
> the total contribution to the systematic should be 10^-3/sqrt(N_pair)=3*10^-4 
> (for 10 pairs).
> (Probably not use conservative number, we can reach 1*10^-4).
>
> For the charge, if we can measure to 1% in 1s, in a typical run of 1 hour, we
> should have more than enough statistics for 10^3. Need to check stability 
> from
> data (g2p/GEP) to see if data stays at that level of stability and also to 
> check at
> 12 hours time scale. If it stays at 10^-3, then we have the same
> systematic uncertainty of 3*10-4. If it is better, then we can do better.
>
> I believe reaching the combined uncertainty (both charge and detector) of 
> 3*10-4 is
> reasonable. But better to have data to support it
>
> Cheers.
>
> Jian-ping
>
>
>
> On 5/5/2013 3:03 AM, Dustin Keller wrote:
>> here is what i was thinking, let me know if we want to add something
>> like this and we can clean it up a bit and add some details.
>> 
>> dustin
>> 
>> On Sun, 5 May 2013, Karl Slifer wrote:
>> 
>>> Hi Oscar,
>>> 
>>> I modified this eq as you suggested to show the explicit dependence on Q
>>> and e.
>>> 
>>> -Karl
>>> 
>>> 
>>> [image: Inline image 3]
>>> 
>>> ---
>>> Karl J. Slifer
>>> Assistant Professor
>>> University of New Hampshire
>>> Telephone : 603-722-0695
>>> 
>>> 
>>> On Fri, May 3, 2013 at 9:38 PM, Oscar Rondon-Aramayo <
>>> or at cms.mail.virginia.edu> wrote:
>>> 
>>>> Hi,
>>>> 
>>>> To further remove any confusion about our method and its errors, I 
>>>> suggest
>>>> that instead of writing eq. (19) in terms of charge normalized, 
>>>> efficiency
>>>> corrected counts, we display the charges and efficiencies explicitly, and
>>>> use raw counts. Although we stated the kind of counts we are using in 
>>>> that
>>>> eq. just above it, it seems Steve missed it.
>>>> 
>>>> Per eqs. (32) and (33) in the appendix 2.2.3, this means just moving Q's
>>>> and
>>>> epsilons to the l.h.sides, since N1 and N are indeed raw counts there, 
>>>> and
>>>> don't make any approximations, like Q1 ~ Q, etc.
>>>> 
>>>> Then, the l.h.s. of eq. (34) would be
>>>> 
>>>> (Q/Q1)*(e/e1)*(N1/N) and
>>>> 
>>>> eq. (19) becomes
>>>>
>>>>   Azz =  2/(f*Pzz)*[(Q/Q1)*(e/e1)*(N1/N) - 1]
>>>> 
>>>> where it's evident that Q's and e's are normalizations or scale factors,
>>>> just like f and Pzz, and change the text above the equation to say raw
>>>> counts, not normalized and corrected ones.
>>>> 
>>>> I don't see any other way to make it any clearer.
>>>> 
>>>> And, of course, we need to emphasize somewhere that the statistical error
>>>> is
>>>> always based on the RAW counts.
>>>> 
>>>> Cheers,
>>>> 
>>>> Oscar
>>>> 
>>>> 
>>>> 
>>>> On Fri, 3 May 2013 17:43:55 -0400
>>>>   Karl Slifer <karl.slifer at unh.edu> wrote:
>>>>> Hi all,
>>>>> 
>>>>> I got a ton of comments, and I think I've implemented them all.  I think
>>>>> the most substantial pertain to the following: (equation numbers refer 
>>>>> to
>>>>> the attached draft)
>>>>> 
>>>>> Eq 17 and 19: Azz expressed as ratio - 1 as suggested by Oscar
>>>>> 
>>>>> Eq 22 : Total time expressed in terms of R_T as noted by Patricia and
>>>>> concurred by Ellie and Oscar.
>>>>> 
>>>>> Page 23 Charge determination systematic : modified to reflect Oscar and
>>>>> JP's suggestions
>>>>> 
>>>>> There were a lot more, so please double check that your suggestions have
>>>>> been satisfactorily included.
>>>>> 
>>>>> The overhead and target sections are still in progress. Anyone have time
>>>>> to help with that?
>>>>> 
>>>>> thanks,
>>>>> 
>>>>> Karl
>>>>> 
>>>>> 
>>>>> ---
>>>>> Karl J. Slifer
>>>>> Assistant Professor
>>>>> University of New Hampshire
>>>>> Telephone : 603-722-0695
>>>> 
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>>> 
>> 
>> 
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