Re: VSMAC1 RUNs in December 1998

Christopher Orth (corth@budoe.bu.edu)
Thu, 17 Dec 1998 17:54:24 -0500 (EST)

Hi All,

It is important that people realize that the current version of
the ZEBRA Rare DST copying is likely to fail for these runs. Why? All
ID=2 buffers will be linked to the first ID=1 buffer of the same event
number. The ID=1 buffer that is chosen will be the first one in the list
of buffers - sort of random.

Anyone analyzing these runs should expect that the WFDs will
sometimes be attached to the "other event".

I don't think fixing the software for these runs is an easy task;
probably the only way to handle this is with the UT time in the header
(?). It is probably more work than is justifiable for a couple runs.

-Chris

On Thu, 17 Dec 1998, Erik Katsavounidis wrote:

> Hi all,
>
> Notice that during the gain reset period, while main (VXMACA) acquisition
> was kept for the 2/3 of the detector, backup (VSMAC1) RUNs were taken
> in parallel for the microvaxes that had their gains just reset.
> Starting with RUN 91245 and on until now, such RUNs collect good data
> for most analyses with the exception maybe of ERP GC.
>
> The only problem with these VSMAC1 is that occasionally the EVENT NUMBER
> got STUCK (due to sync conflicts with the main acquisition?). As a result,
> most of the RARE DSTs produced for these VSMAC1 have actually MORE events
> that they should. If one of the "stuck" events were fulfilling the RARE
> requirements, then ALL such events were eventually selected, i.e., the
> RARE DSTs for these runs are superset of the true RARE DST.
>
> I expect at least 1-2 such VSMAC1 RUNs to be taken until the gain reset
> job is completed.
>
> --Erik
>