Margret
just returned from the Geant4 workshop and reported that it
was very useful and informative. Lots of talks were given, covering
a wide variety of aspects of Geant4: Physics, geometry, and
details of how the program runs. The level of knowledge among the
participants of the tutorial ranged from beginners to experts, and
in fact, it was noted by the organizers that some people were
taking the tutorial for a second time. Margret hopes that she can soon
try out some of the thing that were mentioned during the lectures.
Tayfun
Tayfun showed latest plots from his position analysis.
He plotted the EMEC energy vs beam(mwpc) x position extrapolated to
the centre of EMEC layer 2 for an x-scan with 119 GeV positrons.
He finds a distinctive dip in the response in the region of
x = -25cm to -30cm. It is unclear at the moment, what the
cause of this dip is.
He also plotted the EMEC energy as a function of cell phi, where
cell phi spans one EMEC cell in phi (2*pi/256). The 16 cells that
were hit in the position x-scan where all included in the same
plot (i.e. overlaid) and the variation of the response due to the
absorber plates and readout boards shows up very clearly.
Finally he showed plots of the EMEC energy vs. global cubic time.
the distribution looks essentially flat, and a look at the
normalized energy reveals a remaining variation of about 0.5%.
Tamara
has, for the moment, shelved looking at the timing problem (Michel
is currently investigating this more expert problem).
She is is now working on reproducing the HEC asymmetry plots,
based on the information that this plots is really the results of
a division of two histograms from 2 separate runs by each other.
Now that she knows what actually went into this plot, she was able to
generate a first asymmetry distribution, which looks similar
to the one generated by the MPI group. She will have to figure out
next, whether this plot will turn out the same for other energies too,
and, if so, whether a correction based on this plots will actually improve
the resolution.
Michel
is now now back at doing analysis with Athena and TBRootAna. He has
managed to use ASK to as an interface to Athena, and found bugs in it
that resulted in the experts having to fix things. he also relearned
how to run batch jobs and, thanks to Tayfun and Ashok's help, how to
use bbftp to transfer files from castor to UVic: the command to be
issued on the fates, is, for example,
bbftp -V -p 5 -e 'setoption remoterfio; get /castor/cern.ch/user/l/lefebvre/mydir/file.root file.root' -u lefebvre wacdr.cern.ch
where the 5 means 5 parallel streams.
The aim of his analysis is to document how the response of the EMEC
and HEC depends on the global cubic time. He has looked at runs with
good TDC information and he compared the response of the EMEC, HEC and
(EMEC+HEC) as a function of TDC and global cubic time obtained from
either EMEC, HEC or (EMEC+HEC). This resulted in a good number of
plots. One of the interesting features that appeared was a difference
of 1-2 ns between the cubic time obtained from the HEC and the cubic
time obtained from the EMEC. Work is progressing. Michel also found
that the dependence of the Cubic time as a function of TDC is not a
straight line. This is probably due to biases caused by the cubic
method itself and may have been reported elsewhere before.