[Rivet] HepMC units in AGILe

[Andy Buckley]

On 22/04/10 09:47, Frank Siegert wrote:
> Andy Buckley, Wednesday 21 April 2010:
>> On 21/04/10 17:29, Frank Siegert wrote:
>>> I have the bad suspicion that AGILe doesn't respect the default HepMC
>>> units when filling HepMC events. When using AGILe compiled with
>>> HepMC from GENSER it produces events that claim to have MEV/MM units,
>>> but the numbers are still GEV numbers (e.g. E=900 for a Tev-I beam).
>>>
>>> Am I wrong in my diagnosis (and have just killed 230 jobs in vain) or
>>> is this indeed a relatively serious problem because the bootstrap
>>> script uses HepMC 2.05 from GENSER by default?
>>
>> Could be a serious problem... I can't remember if AGILe is specifying
>> the HepMC units properly, since the experiment version was always a
>> blocker on what was done. I think that Rivet should handle the incoming
>> HepMC units properly, but AGILe quite possibly doesn't write them.
> 
> Well, the problem is not that it doesn't write them. Quite the opposite:
> It does write them (simply because HepMC::IO_GenEvent writes them) but the
> numbers don't correspond to them.
> So when I feed such a generated file into Rivet, it assumes all numbers are
> MeV, even though they were meant to be GeV by AGILe. And of course
> everything will be wrong from there.
> The problem might be that the HepMC::IO_HEPEVT converter doesn't respect
> the default units? I know that at least FPythia in AGILe is affected.

I've added this to AGILe and applied it in all the fillEvt methods:

http://projects.hepforge.org/agile/code/dev/namespaceAGILe.html#a9b2d56290861db0e04bce8342bede11

Hope it does the right thing... could you give it a quick try to see if
I got it right? Thanks.

We'll make this into a new release, soon. I hadn't realised it was so
long since the last one.

Andy

-- 
Dr Andy Buckley
SUPA Advanced Research Fellow
Particle Physics Experiment Group, University of Edinburgh