[b1_ana] LiD, Tensor Workshop Discussions, and Moving Forward

Mon Apr 14 18:55:44 EDT 2014

 Hi Karl et al,

 I agree with Dustin that I thought that Li6D had been put on the backburner.

 I have  appended a graph which shows the 6LiD polarization as a function of magnetic field (Stefan Goertz, Bonn/Bochum): 6Li and D have the same polarization.
The lowest graph is the one we are concerned with (1 K) where , at 5 T , the polarization is ~22% In subsequent. In subsequent measurements we got to 25%. In the beam the polarization grows to ~30% before turning over and falling. The good news is that the rad damage resistance is 3X that of ND3. The bad news is that I have only done two anneals at 180K, one successful, one marginally so. 
Polarizing times are long (see slide in my talk at the workshop), that means thermalizing times are long making it difficult to do a TE measurement, irradiations are more difficult having to be done at ~180K etc. None of these are show stoppers as we did two experiments at SLAC  with 6LiD. But I don't see how we  can show Vector polarizations of 60%., even with the 'extra deuteron' .even if we go to a field of 7.5 T.
And we don't have an  EIO at 213 GHz.

 An issue with ND3 is that it needs cold irradiation to get to P=50% so at NIST we will have to do the regular warm irradiation followed by a cold irradiation at 4 K.
 All this implies a lot of work in the case of either material so let's choose wisely.

   Just to confirm, the meeting is Thursday at 2 pm, right. I have a conflict which I'll try and resolve.

     Don

On Mon, 14 Apr 2014 11:00:30 -0400
 Karl Slifer <karl.slifer at unh.edu> wrote:
>Hi Dustin,
>
>I'm very glad that you'll be looking into the high field response for ND3;
>I agree that this is the logical place to start.  I also believe it is
>reasonable and logical to keep LiD as an option considering the extended
>discussions of pros and cons we had at the workshop.  Going back quite a
>few years, we initially vetoed LiD for two main reasons (as I recall):
>
>-The long time to thermalize and the issue of whether we can really treat
>6Li as 4He+D
>
>The first point is just one consideration in calculating the overall FOM,
>which we can (and should) compare to ND3.  This takes no new cool downs.
>And the theorists at the workshop were open to point 2, at least for DIS
>experiments like b1, although we would clearly need further theory support
>if we chose LiD.   So there is no "shift to LiD" as I see it: LiD is an
>option, like ND3 is an option, like solenoid or open geometry magnet is an
>option.  The pros and cons need to be evaluated, and most of the bigger
>issues can be considered to see if they justify the substantial resources
>needed for a cool down.
>
>best,
>
>-Karl
>
>
>
>
>On Mon, Apr 14, 2014 at 10:28 AM, <dustin at jlab.org> wrote:
>
>>
>>
>> Hi,
>>
>> I am not totally sure why the shift to LiD considering what we already
>> know and understand about it.  There was some concern about what can be
>> achieve with ND3 during the meeting but unless I missed something its
>> based on lack of research and data on ND3 and nothing else.  LiD posses a
>> lot of problems which is why we vetoed it to start with.  Not to say that
>> these problems don't have solutions but there maybe better places to put
>> the time and focus for now.  I will not be looking at LiD in the lab for a
>> while.  I am interested in what can be done with d-butenal (cause its easy
>> and hold a lot of test potential) and ND3 (cause it hold the best
>> experimental potential).
>>
>> >From what I recall the only reason LiD was even brought up was because we
>> are not sure what ND3 will do under higher field.  Given the right dose
>> under warm irradiation there is good reason to believe it will perform
>> quite nicely.  This has yet to be shown, but its an easy test.  Until we
>> have these results there are probably better things to focus on than LiD.
>> For example simulations and magnet field configuration.  This is a large
>> task but if there is the opportunity to buy a new magnet it will be an
>> essential task.  Results of systematics have a strong dependence on the
>> configuration and understanding of acceptance for each configuration.  I
>> will not take this task on alone I'm very busy in the lab, but I am
>> willing to help with tosca, design and communication with Oxford etc.
>>
>>
>> dustin
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> > Hi
>> >
>> > In advance of our meeting,
>> > here<https://www.slac.stanford.edu/exp/e161/target/cdrslacr3.pdf>is
>> > the conceptual design report for the E159 solenoidal target using LiD.
>> >  I think this is a good reference to start with for considering some of
>> > the
>> > suggestions that emerged from the tensor workshop. In particular,
>> >
>> > - Fig 1 gives LiD spin up times at 5T and 6.5T which is on the order of
>> > 30-40 hours. I think that with LiD, the polarization just keeps growing
>> > when you put beam on it, so data taking does not necessarily need to wait
>> > until max polarization is reached. T.E.s become a big time investment,
>> and
>> > we would probably need to seriously consider AFP to kill the
>> polarization,
>> > and maybe Josh's suggestion to simultaneously polarize the unused cell
>> > (which is just outside the uniform region) by use of an extra
>> compensating
>> > coil.
>> >
>> > -Max polarizations look to be about Pz=62% and Pz=72%, which corresponds
>> > to
>> > about Pzz=30% and Pzz=40% respectively.  I assume this curve is for 1K,
>> > but
>> > I can't access the original article (V. Bouffard et al J. Physique, 41,
>> > 1447 (1981)).
>> >
>> > -the paper discusses using a transverse solenoid dipole for adiabatic
>> > field
>> > reversals
>> >
>> > -The proposed solenoid would have accomadated a 1cm diameter target, with
>> > 5cm length in a 10E-4 uniform field, with a 20 cm (8 inch) diameter bore.
>> >  The price tag in 2001 was 230K. Inflation adjustment puts that at about
>> > $320K today.  The EIO tube ($95K) and Roots pumps(93K) in 2001 dollars
>> > inflates to about another $250K today.  These are not the only expenses,
>> > but they would be the main ones summing to 570K.  There's plenty of other
>> > smaller expenses, so maybe 800-900K for a complete solenoid system?
>> >
>> > (For reference our UNH solenoid is 7T with 10E-4 uniformity over a 5 cm
>> > DSV, with a clear bore of 4 inches,and is about 14inches long.)
>> >
>> >
>> > -Karl
>> >
>> >
>> >
>> >
>> >
>> >
>> > On Fri, Apr 4, 2014 at 1:06 PM, Elena Long <ellie at jlab.org> wrote:
>> >
>> >> Good afternoon,
>> >>
>> >> Thank you all for filling out the poll. Based on it, let's have our
>> >> next meeting on Thursday, April 17 at 2pm.
>> >>
>> >> The things that I would like to discuss are new rates calculations
>> >> using LiD and He2D (where Li is assumed to be HeD), I want to make sure
>> >> that we take the time close enough to the Tensor Workshop to hash out
>> >> any remaining discussions left over from the Workshop before they slip
>> >> from our minds, and to revisit our plan for achieving our condition
>> >> particularly given the pessimistic viewpoints that were raised during
>> >> the target session. I welcome any other agenda topics as well.
>> >>
>> >> Take care,
>> >> Ellie
>> >>
>> >> Elena Long, Ph.D.
>> >> Post Doctoral Research Associate
>> >> University of New Hampshire
>> >> elena.long at unh.edu
>> >> ellie at jlab.org
>> >> http://nuclear.unh.edu/~elong
>> >> (603) 862-5312
>> >>
>> >> On Fri 04 Apr 2014 11:57:55 AM EDT, Oscar Rondon-Aramayo wrote:
>> >> > Hi Ellie and all b1 people,
>> >> >
>> >> > I filled the poll, but I'm not sure about the reason for the meeting.
>> >> > Is there something time sensitive that we should discuss, such as
>> >> > communications with the PAC or the like? It would be a good idea to
>> >> > circulate a tentative agenda of the items that would be covered.
>> >> >
>> >> > Otherwise, it may be more effective to just share ideas and proposals
>> >> > by email, which also serves to document the process.
>> >> >
>> >> > Cheers,
>> >> >
>> >> > Oscar
>> >> >
>> >> > On Thu, 3 Apr 2014 17:14:10 -0400
>> >> >  Elena Long <ellie at jlab.org> wrote:
>> >> >> Good evening,
>> >> >>
>> >> >> Please take a moment to fill out the scheduling poll below by
>> >> >> tomorrow at 1pm so that we can schedule the next b1 meeting.
>> >> >>> http://doodle.com/4ytu2b3b5gqqaz7d
>> >> >>
>> >> >>
>> >> >> Take care,
>> >> >> Ellie
>> >> >>
>> >> >>
>> >> >>> On Apr 2, 2014, at 1:45 PM, "Elena Long" <ellie at jlab.org> wrote:
>> >> >>>
>> >> >>> Good afternoon,
>> >> >>>
>> >> >>> Since it looks like a number of people aren't able to make it next
>> >> >>> week, let's postpone to the following week. Since I imagine our
>> >> >>> schedules have changed a bit since our last meeting, please fill out
>> >> >>> the Doodle poll below by Friday afternoon so that we can schedule
>> >> >>> the next b1 meeting.
>> >> >>>
>> >> >>> http://doodle.com/4ytu2b3b5gqqaz7d
>> >> >>>
>> >> >>> Thank you,
>> >> >>> Ellie
>> >> >>>
>> >> >>> Elena Long, Ph.D.
>> >> >>> Post Doctoral Research Associate
>> >> >>> University of New Hampshire
>> >> >>> elena.long at unh.edu
>> >> >>> ellie at jlab.org
>> >> >>> http://nuclear.unh.edu/~elong
>> >> >>> (603) 862-5312
>> >> >>>
>> >> >>>> On 04/01/2014 11:07 AM, Long, Elena wrote:
>> >> >>>> Good morning,
>> >> >>>>
>> >> >>>> Since we last had a b1 meeting, a lot has happened. I was wondering
>> >> if
>> >> >>>> we could schedule a meeting to re-group and plan a path forward,
>> >> >>>> particularly given the target discussions that happened during the
>> >> >>>> Tensor Workshop. Would next Thursday (4/10) at 1:30pm work for
>> >> >>>> everyone?
>> >> >>>>
>> >> >>>> Take care,
>> >> >>>> Ellie
>> >> >>>
>> >> >>> _______________________________________________
>> >> >>> b1_ana mailing list
>> >> >>> b1_ana at jlab.org
>> >> >>> https://mailman.jlab.org/mailman/listinfo/b1_ana
>> >> >>
>> >> >> _______________________________________________
>> >> >> b1_ana mailing list
>> >> >> b1_ana at jlab.org
>> >> >> https://mailman.jlab.org/mailman/listinfo/b1_ana
>> >> _______________________________________________
>> >> b1_ana mailing list
>> >> b1_ana at jlab.org
>> >> https://mailman.jlab.org/mailman/listinfo/b1_ana
>> >>
>> > _______________________________________________
>> > b1_ana mailing list
>> > b1_ana at jlab.org
>> > https://mailman.jlab.org/mailman/listinfo/b1_ana
>> >
>>
>>
>> _______________________________________________
>> b1_ana mailing list
>> b1_ana at jlab.org
>> https://mailman.jlab.org/mailman/listinfo/b1_ana
>>

-------------------------------------------------------------
D. G. Crabb
Research Professor of Physics
University of Virginia
382 McCormick Rd.
Charlottesville
VA 22903
USA
Phone: 434-924-6790
Fax:    434-924-4576
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Li6D-polvs _B.pdf
Type: application/x-octet-stream
Size: 22374 bytes
Desc: not available
Url : https://mailman.jlab.org/pipermail/b1_ana/attachments/20140414/6e2cf1b0/attachment-0001.bin 