Print

Print


Hello,

I wanted to bring up a few things that I intended to discuss in the meeting
today, but was unable to due to an unexpected issue to which I had to
attend.

The first issue I wanted to discuss concerns truth information in
clustering. I found that all of the truth information is lost from
clustering Monte Carlo at the digitization stage. I think it would be
useful to retain this. However, I see that we create "RawCalorimeterHit"
and "RawTrackerHit" objects, which do not support storing this information.
Does anyone have any suggestions on what the correct way to store truth
information would be in this case?

The second issue is that currently, our readout code is a bit messy. I
think that it would be improved by separating out the 2014 functionality,
which is currently mixed in with the regular behavior in a bunch of if/else
blocks. This makes the code much harder to maintain and also increases the
risk that any changes to it will break the old functionality. I think it
would be better to lock the old 2014 code in its current state in separate
drivers explicitly for that purpose.

Lastly, I wanted to see if anyone had advice concerning the best way to
handle an LCSim issue. As we move forward with the hodoscope trigger, it
will become necessary to trigger on both the hodoscope and the calorimeter
simultaneously. Currently, this is actually somewhat challenging. The
reason for this is that many LCIO objects in the data stream are
"time-displaced" in the readout stage. This occurs because, for things like
pulse emulation and clustering, we have to wait extra events passed where
an object actually occurs, to create the simulated object. This is easiest
to see for clustering. A cluster can only be formed by looking over a +/-T
ns window. Since events are 2 ns beam bunches in readout, this means we
need to wait at least T/2 events before performing clustering. However,
when we then create clusters, they must be inserted into the current event,
which is T/2 events in front of the seed hit's original event. This creates
an issue when the hodoscope hit is now in a totally separate event from the
clusters and depends in a complicated fashion on both the "displacement"
induced by the digitization/hit formation drivers and clustering drivers.
(These in turn depend on their own settings.) Can anyone suggest a way to
handling this to ensure that the correct hodoscope hits and clusters are
compared, short of maintaining a large buffer?

Thanks,

Kyle

########################################################################
Use REPLY-ALL to reply to list

To unsubscribe from the HPS-SOFTWARE list, click the following link:
https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=HPS-SOFTWARE&A=1