[G13] dodgy set of runs in g13b -- beware

[Daria Sokhan]

Hi everyone,

Just a note for anyone analysing g13b data, the dataset where the coherent
edge was supposed to be set at 1.5 GeV contains a freak batch of runs where
it had obviously been accidentally set at 1.7GeV (see plot attached, shows
coh edge for both PARA and PERP summed, in spite of what the title says).
There is nothing about that in the log book as far as I could find, and it's
labelled as 1.5 in the run data table and on the wiki.

These are in the Ee = 4065MeV batch, run numbers 55048 - 55082 inclusive.

I would treat that data with caution, in terms of applying polarisation
values to it, as I saw some significant systematics between asymmetries
calculated from it and the rest of the data at the same energies. Anywhere
up to 40% or so.

Thanks,
Daria




-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Ms Daria Sokhan
PhD Student
Physics Department
James Clerk Maxwell Building                     Phone:  +44 131 650 5284
King's Buildings                                             Fax:    +44 131
650 7003
University of Edinburgh                               E-mail:
daria.sokhan at ed.ac.uk
Edinburgh EH9 3JZ
UK
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The University of Edinburgh is a charitable body, registered in
Scotland, with registration number SC005336.




-- 
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Ms Daria Sokhan
PhD Student
Physics Department
James Clerk Maxwell Building                     Phone:  +44 131 650 5284
King's Buildings                                             Fax:    +44 131
650 7003
University of Edinburgh                               E-mail:
daria.sokhan at ed.ac.uk
Edinburgh EH9 3JZ
UK
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The University of Edinburgh is a charitable body, registered in
Scotland, with registration number SC005336.
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