[b1_ana] draft V3

[Dustin Keller]

We are still using the best possible approach with Azz, I will try to
write up an additional appendix to explain away the drift the best i
can.

dustin

On Sat, 4 May 2013, Karl Slifer wrote:

> Hi Dustin,
>
> Lets put aside the actual method for a moment, and discuss the technique
> later, if this is fruitful....
>
> My basic question is : if we flipped 10 times a day and ran each point for
> 10 days, that gives 100 "buckets" or "slugs" of data.  So I think a 1% (or
> 10^-2) drift over this 10 days would be suppresed to a 10^(-3) effect.
> This is difficult, but I think doable.  Or do we need to have a 1000 slugs
> in order to reduce to 10^-4?
>
> -Karl
>
>
>
>
> On Sat, May 4, 2013 at 8:19 PM, Dustin Keller <dustin at jlab.org> wrote:
>
>> Hi,
>>
>> It is possible to use an additional loop to annihilate polarization, it is
>> similar to AFP, but different, not needing to go to negative polarization.
>> This would require an additional loop most likely on the outside of the
>> cup.
>>
>> dustin
>>
>> On Sat, 4 May 2013, Karl Slifer wrote:
>>
>>> PPS : please note that in the overhead I assumed we would switch
>>> polarization states twice per day and I assumed 2 hours each time.  I
>> think
>>> this would imply about 10 "buckets" of polarized counts and 10 "buckets"
>> of
>>> unpolarized counts for each of our 3 x-points.   It is our dominant
>>> overhead at 5 days total.
>>>
>>> I think we may have a little room to move here.  Please see the attached
>>> plot from g2p data, where we depolarized the (proton) target by pumping
>>> with microwaves in less than 4 minutes.  The pump up is also very fast
>> with
>>> the new fridge and blasting the wattage of the new microwave cavity the
>>> pump up is about 30 mins to the negative state.  I think polarizing in
>> the
>>> positive state is usually a little faster.
>>>
>>> So, perhaps we can be a little more aggressive in our overhead estimate
>> :5
>>> or 10 mins for depolarizing and 30 mins to polarize.  That would give us
>>> the flexibility to increase the number of "buckets" to say 10 or 12 total
>>> per day.  It will be a large overhead (about 12 days just for this), but
>> oh
>>> well.  Would this be sufficient to control the known drifts?
>>>
>>> A little more radical would be to explore the idea of flipping from
>>> positive to negative tensor polarization rapidly with an AFP type flip,
>>> which I believe is near instantaneous.  This is essentially what happens
>>> with hole burning anyway I think.
>>>
>>> -Karl
>>>
>>>
>>>
>>> ---
>>> Karl J. Slifer
>>> Assistant Professor
>>> University of New Hampshire
>>> Telephone : 603-722-0695
>>>
>>>
>>> On Sat, May 4, 2013 at 6:47 PM, Karl Slifer <karl.slifer at unh.edu> wrote:
>>>
>>>>
>>>> Hi All,
>>>>
>>>> I've posted the updated draft at
>>>>
>>>> https://dl.dropboxusercontent.com/u/59933793/tensor_b1_v03.pdf
>>>>
>>>> There is some lagtime for implementation, but I think this reflects
>> pretty
>>>> well where our discussion was about 24 hours ago.  However, we still
>> need:
>>>>
>>>> -updated rates/kin plots from Ellie or Patricia and values for the table
>>>>
>>>> -some consensus on how to address Steve's comments.
>>>>
>>>> It seems we have three options with time running short.
>>>>
>>>> 1) List all possible factors that drift with time and atleast sketch a
>>>> plan to deal with them.
>>>>
>>>> 2) go back to difference of counts.
>>>>
>>>> 3) Cancel submission and work on this for next PAC.
>>>>
>>>> I lean to the first, Oscar leans to the second.  I'd very much like to
>>>> find some consensus on this.  Am I the only one still nerding it up in
>>>> front of my computer on this beautiful spring day?
>>>>
>>>> -Karl
>>>>
>>>> PS : If anyone makes suggestions for changes I would very much
>> appreciate
>>>> that they be in a form that I can put into the document quickly.
>>>>
>>>> ---
>>>> Karl J. Slifer
>>>> Assistant Professor
>>>> University of New Hampshire
>>>> Telephone : 603-722-0695
>>>>
>>>
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>