[Frost] target pol issue: runs 62677-62690

[Franz Klein]

Mike and Natalie!
thanks for digging that out: it seems that epics did not get the holding field for these runs (=0.00) and my simple script took this as nonnegative (i.e. did not change the sign of the NMR field).

I corrected the wiki page (https://clasweb.jlab.org/rungroups/g9/wiki/index.php/62609_-_62704)
and the txt files in userweb.jlab.org/~fklein and /home/fklein/rootbeer2.1/dat/g9b_p1v1RunTable.dat

My apologies,
Franz

----- Original Message -----
From: "Michael Dugger" <dugger at jlab.org>
To: "Steffen Strauch" <strauch at sc.edu>
Cc: natalie at jlab.org, "Ross Tucker" <rjtucke at gmail.com>, "Franz Klein" <fklein at jlab.org>, "Hao Jiang" <jiang24 at email.sc.edu>
Sent: Thursday, December 5, 2013 2:38:06 PM
Subject: Re: target pol issue


Hi,

In the run table we have zero magnetic field current for runs 62677 
through 62689. Since the sign of zero is positive and the runs that are 
previous and after the group 62677-62689, then the sign of the 
polarization will flip.

Take care,
Michael

On Thu, 5 Dec 2013, Steffen Strauch wrote:

> Dear Natalie,
>
> I am forwarding the message to Hao (Hao Jiang <jiang24 at email.sc.edu>).
> We will continue the study of run-dependent systematics.
>
> All the best,
> Steffen
>
>
>
> On Dec 5, 2013, at 11:32 AM, <natalie at jlab.org> wrote:
>
>> Hello,
>> I was looking into some issues to try to figure out before and after
>> quench issues. In the run set from 62609-62704, I noticed that one of my
>> histograms that show whether it is negative or positive target
>> polarization was not all positive (as it should be since its minus minus
>> according to wiki). So I started looking to my polarization table and then
>> the wiki.
>>
>> https://clasweb.jlab.org/rungroups/g9/wiki/index.php/62609_-_62704
>>
>> So here I looked and noticed that runs 62677-62690 are all of a sudden
>> negative. Should they be negative or they are really positive? Or was the
>> target flipped in between? Has anyone else noticed this issue?
>>
>> Just another thing I came across.....sometimes too many small things!! I
>> know this isn't going to solve a major issue but for sure an asymmetry
>> could be slightly off with a few wrong target polarization directions.
>>
>> Natalie
>>
>> PS Steffen, I am not sure of Hao's email, but wondered if you guys came
>> across this since you are looking into F now...
>>
>

-- 
===============================================================
                  Franz J. Klein, Associate Professor 
                  CUA, Department of Physics
                  Washington, DC 20064
  office: Hannan Hall 206          phone: 202-319-6190 
  or: Jefferson Lab,CC F-243       phone: 757-269-6672 
---------------------------------------------------------------