Edited on 5/1 to reflecte new status bit assigments for bits 3 and 4.

The current BSMD status bits are as follows:

Bit 2: Bad pedestal peak/multiple pedestal peaks. This is described in more detail here. Examples can be found in crate2_ped.pdf pp 207 and 314 and crate4_ped.pdf p 133.

Bit 3: Pedestal peak has bad sigma, sigma<1 or sigma >15

Bit 4: Chi squared value from gaussian fit is greater than 1000 (i.e., pedestal has a funny shape)

Bit 5: Strip is exactly identical to the previous strip

Bit 6: The ratio of the integral of channels 300-500 to the total integral does not fall between .0001 and .02

Bit 7: The ratio of the integral of channels 500-800 to the total integral does not fall between .00004 and .02

Bit 8: The ratio of the integral of channels greater than 800 to the total integral does not fall between .00005 and .02

Note that this means that dead channels have status 111xxxx0->448 (or greater).

The attached pdfs crate2 and crate4.pdf have the pedestal distributions, taken from NZS data, and the overall distributions, taken from ZS L2W data, overlayed; crate2_ped and crate4_ped.pdf have only the pedestal distributions. The NZS data used was taken from my monitoring for fills 10415-10489. The L2W data came from fills 10383-10507. Additionally, at the beginning of each module is a summary page that has plotted the distributions for the ratios used to determine bad status bits 6, 7, and 8, and the overal distribution of status vs. strip for eta and phi.

Finally, there are a couple of possible new problems. Page 18 in crate4_ped.pdf has several examples of pedestal distributions that have shoulders. Page 20 has a few examples of pedestal distributions with a small, skinny peak perched on top of a large, broad distribution. At the moment I have no bad status bit for either of these, and any peak with either of these features would almost certainly not be marked bad (even though I did manage to catch one of the ones on page 20).

Edit: Scott suggested during the phone meeting today that perhaps the problem of a small peak on a broad distribution was due to time variation of the pedestal width, and in the plot below you can see that he was correct: the strip initially has an extremely wide pedestal which then shrinks down suddenly. Futhermore, looking at one of the strips that had a sort of shoulder to it, you can see that this is just a less-pronounced version of the double peak problem seen before: the pedestal goes up by 10 for a much shorter time frame, thus producing a shoulder rather than a second peak. This suggests that, as Scott said, these channels should still be usable, and that once we begin breaking status down by time these funny shapes should be less of a problem.