[EvtGen] S-wave with EvtGen

[John Back]

Hi Giacomo, Alberto,

On 26/07/18 15:08, Alberto Sanchez-Hernandez wrote:
> The current production version of EvtGen at CMS is 1.6.0
>

OK, thanks for letting us know. The EvtGen version with the new features 
will probably be called version 1.8.0.

We'll announce it when its available via our usual mailing list
evtgen-announce at projects.hepforge.org.

Regards,
	John.

> On Thu, Jul 26, 2018 at 9:03 AM Giacomo Fedi <giacomo.fedi at cern.ch
> <mailto:giacomo.fedi at cern.ch>> wrote:
>
>     Hi John,
>
>     thank you for your answer. I'm looking forward to see the S-wave and
>     the other "extra" models in the HepForge repository.
>
>     @Alberto, is the CMS version on the same page of the mentioned
>     repository?
>
>     Best,
>     Giacomo.
>
>     On Wed, Jul 25, 2018 at 2:04 PM John Back <J.J.Back at warwick.ac.uk
>     <mailto:J.J.Back at warwick.ac.uk>> wrote:
>
>         Hi Giacomo,
>
>          > On 16/07/18 10:12, Giacomo Fedi wrote:
>          > Hi EvtGen authors,
>          >
>          > I was wondering if it is now possible to produce samples of
>         P+S wave
>          > in the JpsiPhi decay. In principle we would need an improved
>         PVV_CPLH
>          > model which right now is simulating only the P-wave.
>          >
>
>         After carefully rechecking the LHCb EvtGen repository, we have
>         found
>         that there is in fact a model that generates Bs -> J/psi (mu mu)
>         K K
>         decays which includes the phi and f0 resonances as well as a
>         non-resonant S-wave component, with decay time dependence.
>
>         It it called EvtBsMuMuKK and uses the amplitude formulae from
>         PRD 87,
>         072004 (2013), although the model imposes an ad-hoc K+K-
>         kinematic upper
>         mass limit of 1.2 GeV (specified via a decay file parameter)
>         since there
>         are issues extending it up to 2.3 GeV or so.
>
>         We will try to make this model available, along with the useful
>         ones
>         currently in the LHCb EvtGenExtras package, in our HepForge
>         repository
>         and release it around the timescale of September/October, owing
>         to the
>         summer holiday period.
>
>         Regards,
>                  John.
>