[Pythia8-announce] Pythia 8.170 now available

[Torbjorn Sjostrand]

Dear All,

Pythia 8.170 has now been released, and can be downloaded from

http://home.thep.lu.se/~torbjorn/Pythia.html

as usual. The list of news and improvements include:

* Reading of ALPGEN parameter and event files now available.

* MLM matching is implemented, currently for ALPGEN events.

* The CKKW-L merging machinery has been upgraded.

* Central diffraction now available for all the different Pomeron
   fluxes, and some previous kinematics choices have been improved.

* The tau decay machinery has been augmented by matrix elements
   for several production and decay modes.

* Flavour violating decays have been added for sparticles.
   R-parity violating decays of R-hadrons allowed.
   Some bug fixes for SUSY processes and SLHA input.

* Resonance decays can be performed standalone, i.e without being
   part of a process.

* Further ATLAS tunes included.

* Angular correlations in decay chain H -> gamma Z0 -> gamma f fbar.

* Possibility of separate prefactors to the renormalization and
   factorization default pT2 scale for showers.

* Built-in possibility to reweight 2 -> 2 events by a power of pT.

* SlowJet can tell which jet a particle has been assigned to.

* The Info class can give generation statistics for subprocesses.

* Particle masses and widths have been updated to agree with the
   2012 RPP values.

* Several new methods have been added to the UserHooks machinery,
   offering further functionality.

* Improved HepMC interface.

* Extended Les Houches event file handling.

* The configure script and makefile have been expanded to allow
   automatic installation in reqested location.

* New check that version number of the code matches that of the
   xmldoc/ data files. If not, program will not run.

* Automatic check that mother and daughter indices give a
   consistent event history.

* Minor improvements in the hadronization machinery, especially
   for junctions, leading to fewer error messages.

* Fewer warning messagess, notably by tolerating weights just
   barely above unity.

* Several bug fixes.

For a more extensive listing, see the "Update History" in the
online html/php manual.

We encourage you to upgrade to this new version and, as always,
look forward to constructive feedback. (Although our limited
manpower means that not all suggestions/requests can be met.)
A follow-up version is foreseen in a near future.

The Pythia 8 Collaboration
(Torbjörn Sjöstrand, Richard Corke, Stephen Mrenna,
Stefan Prestel, Peter Skands)