[Halld-offline] Minutes, Offline Software Meeting, January 25, 2012

[Mark M. Ito]

Folks,

Find the minutes at 
https://halldweb1.jlab.org/wiki/index.php/GlueX_Offline_Meeting,_January_25,_2012 
and below as plain text.

-- Mark
_____

GlueX Offline Meeting, January 25, 2012
Minutes

Present:
* CMU: Will Levine, Paul Mattione
* FSU: Nathan Sparks
* IU: Ryan Mitchel, Kei Moriya
* JLab: Eugene Chudakov, Mark Ito (chair), David Lawrence, John
Leckey, Sascha Somov, Simon Taylor, Ivan Tolstukhin, Elliott Wolin,
Beni Zihlmann
* Regina: Andrei Semenov
* UConn: Richard Jones

Announcements

* Simon announced that the memory explosion (a.k.a. memory leak
problem) should not occur anymore. He implemented changes suggested
by Richard. Other related issues with track finding raised in
earlier meetings are still being addressed.
* David announced that the nightly builds are completing successfully
now. There was an issue with interaction of the make system and the
new C++ API for HDDM. Multiple files differing only in their suffix
cause problems. Base names were changed to fix the problem. Also
certain C++ compilations require a search of a new directory and
now this is done.

Review of minutes from the last meeting

We reviewed [38]minutes of the December 14th meeting.
* The 1-2-3-4 scheme for BCAL read-out the default. Thanks to Will
and David.
* David made a clarification. The EVIO input to JANA code has been
made into special version to support the FCAL beam test in Hall B,
in particular support for Flash-250 data has been added. This
capability will serve as a base for future flash support.
* David remarked that the features of the HDF5-based DST data scheme
presented by Gagik Gavalian might be useful in addressing the issue
long-term preservation of data. Richard pointed out that the design
of HDDM was motivated by this concern in the first place. Mark
reminded us that Gagik's scheme can naturally store auxilliary
information, such as calibration constants, so that systems which
serve that information do not have to be preserved. Mark also
thought that this scheme is something to keep in mind, but is
probably not a front-burner issue for us now.
* Although Dmitry Romanov installed the CCDB system on the CUE before
leaving the USA, none of us have played with it much since. We need
to organize active testing of the system.
* Richard asked about deployment of the calibration database on
off-site institutions. In particular, he hoped that the use case
where calibration sets are being generated and tested repeatedly,
as is often the case, was adequately support. David noted that
using local files for constants was in the orignal JANA scheme.
Mark told us that local files would be supported for the CCDB as
well, but the implementation is not there yet.

Reconstruction sub-group reports

Calorimeters

Will reported on his recent work in understanding spurious clusters in
the BCAL reconstruction. He believes that many of these come from
random dark noise hits pulling the time of legitimate photon shower
hits such that they are identified as separate clusters. See [41]his
wiki page for details. We had an extended discussion about how to deal
with this; overlapping issues include:
* Should the dark hits be introduced in HDGeant or in mcsmear?
* Should HDGeant generate waveform information to allow realistic
inclusion of dark noise?
* Do we need to revisit the method of dark noise injection in mcsmear
to add realism?

David agreed to summarize the situation with respect to dark noise
simulation and present it at a future meeting.

Tracking

* Simon reviewed recent changes to the tracking code. See his slides
for details. They addressed:
+ Recent changes to tracking code
+ Charge from fit
+ Recent changes to Kalman filter
+ Effects of hit pruning in filter
* Paul presented studies of π^+'s with momentum of 150 MeV/c, at 90°
in polar angle. These generally curl around back to the target and
may do so multiple times. See [43]his wiki page for details of his
study. The track multiplicity distributions for the various stages
of tracking vary quite a bit from stage to stage and have very wide
distributions considering that only a single track was generated.
Mark remarked that Paul had chosen a difficult corner of phase
space that would likely require special code to deal with, code
that is nowhere present in the repository at present. He also
mentioned that the identification of these "curlers" was more
easily done with global information; depending on local hit-to-hit,
step-to-step information could be unreliable. Paul said that he has
some ideas on how to address these tracks and that he would pursue
them.

HDDM's C++ API

Richard started leading us through his [45]notes on the new API. The
code was recently checked into the repository.

Unfortunately we had to end the presentation early due to over-running
our reserved time in the meeting room at JLab. The Chair promised
Richard another shot at a future meeting; in the mean time those
interested can look at his notes. Luckily, they are done in a
pedagogical style.

New Action Items

1. Organize active testing of the CCDB. -> Mark
2. Present a summary of dark noise generation in the BCAL. -> David

Retrieved from 
"https://halldweb1.jlab.org/wiki/index.php/GlueX_Offline_Meeting,_January_25,_2012"

References

38. 
https://halldweb1.jlab.org/wiki/index.php/GlueX_Offline_Meeting,_December_14,_2011#Minutes
41. https://halldweb1.jlab.org/wiki/index.php/BCAL_reconstruction_01/16/2012
43. https://halldweb1.jlab.org/wiki/index.php/Mattione_Update_01252012
45. 
https://docs.google.com/document/d/1qOKJLlk7KJVRkuDUm3OnmTU3ZJyx8N3_F7qeVUgTi2M/edit#heading=h.hl7n0xfy00ld