[Rivet] Summary of today's Rivet meeting

[Andy Buckley]

Hi y'all, here's a summary of the issues arising from today's phone meeting:

* Next week's meeting will be at 2pm on Monday 6th Oct. *

1. We want to make sure that the W+jets analysis is in a suitable state
for use in future tutorials: we will want to have a dependable
demonstration tarball for the YETI meeting at Durham in January. The
remaining issue seems to be the normalisation. The impression was that
this is NOT a cross-section issue, but related to the implementation of
isolation cuts, possibly in the VetoedFinalState projection.
 * EMILY: can you let us know the current state of your work on this
analysis?

2. There are problems with the pT distribution shape in the D0_2001_
analysis, particularly for the W pT, which falls off far too rapidly and
screws up the Z/W pT ratio histogram. There are also normalisation
issues, "prossibly" related to the LO vs. NLO cross-section.
 * LARS: commit improved W reconstruction and investigate reasons for
anomalous W pT shape. Check the cross-section vs. normalisation issue.

3. We need to make the generator run conditions for each analysis
clearer. In the long term this should be done via extended Analysis
metadata functionality, but in the short term we'll add Doxygen comments.
 * HENDRIK: add run condition metadata comments for Professor UE tune
analyses
 * ANDY: add the metadata for the other analyses.
Andy has to start first ;)

4. Frank will be starting work on a new validation tool for Rivet
analyses and generators in the next few weeks. If you want to get
involved, mail him and Andy.
 * FRANK and ANDY: get things started, hack first version
 * ANYONE ELSE: implement a Projection unit testing suite if you feel
you have the time!

5. We have more issues with the Genser bootstrapping script, including
failing generator builds and a general animosity for its habit of
downloading 800 MB of utilities before even beginning to get any generators.
 * ANDY: email Alberto to get this discussed in the Wednesday Genser meeting
 * ANDY, JON, LARS, JAMES: attend the Genser meeting on Wednesday,
preferably having tested the script so you can say something intelligent
about it ;)
http://lcgapp.cern.ch/project/simu/generator/genser-bootstrap.html

6. Problem of HepMC not storing any cross-section information.
 * ANDY: Implement an extra rivetgun switch to explicitly pass a nominal
cross-section for analyses that need it, if a HepMC file is being read.
 * ALL: Keep pressing HepMC to provide a GenEvent data member /
IO_GenEvent format element for storing cross-sections.

7. James reported problems that users of Atlas kits had in using Rivet_i
in Athena, since the kits don't include Rivet.
 * JAMES: Find out if this is a Genser or Atlas problem, maybe Sebastian
Boeser is a good first person to ask. Raise the issue at the Genser
meeting if it is a Genser problem.

8. For validation, Professor tunes and general goodness, we want to have
a documented procedure for using Rivet on the Grid.
 * JAMES: Test Rivet using non-Athena Ganga or/and native LCG subission
+ hand-made tarball of built libs. Provide a pre-built tarball when it
works.

Best wishes,
Andy

-- 
Dr Andy Buckley
Institute for Particle Physics Phenomenology
Durham University
0191 3343798 | 0191 3732613 | www.insectnation.org