PGS is a simulation of a generic high-energy physics collider detector with a tracking system, electromagnetic and hadronic calorimetry, and muon system. It is designed to take events generated with popular event generators like PYTHIA and HERWIG and produce semi-realistic reconstructed physics objects such as photons, electrons, muons, hadronically decaying taus, and hadronic jets (including b- and charm-tagging). Many basic detector parameters are configurable using a detector parameter file, which includes calorimeter segmentation and resolution, tracking coverage and resolution, and other configurable parameters.

PGS is very simple: for every final state generated particle, a calorimeter energy deposit is simulated, and a track is simulated in the case of long-lived charged particles. From this information, the "high-level" physics objects (photons, electrons, ...) are reconstructed just as in most modern high energy physics experiments.

PGS is designed to be fast. And, that having been said, there are many things that are not simultaed in PGS, including secondary interactions, multiple interactions, z-vertex spread, bremsstrahlung, pair production, decays in flight, magnetic field effects, detector material, and probably other things as well. But it's fast.

PGS is, well, pretty good. Most collider detector analyses suffer most from geometric acceptance and resolution issues, and PGS gets those mostly right. For many analyses you will find (we hope!) that the answer from PGS agrees within a factor of two of the answer you might obtain with a full-fleged detector simulation. In many cases the agreement is much better, of the order of 20%. But, as with any detector simulation, you should always be aware of the limitations and avoid drawing physics conclusions which might depend too much on absolute accuracy. PGS is an excellent tool for prototyping analyses and techniques, but it only goes so far.


PGS is the product of many people: John Conway (UC Davis), Ray Culbertson (FNAL), Regina Demina (U. Rochester), Ben Kilminster (Ohio State), Mark Kruse (Duke), Steve Mrenna (FNAL), Jason Nielsen (LBNL), Maria Roco (now at Lucent), Aaron Pierce and Jesse Thaler (Harvard), and Tommer Wizansky. Special thanks to Matt Strassler, Nima Arkani-Hamed and Liantao Wang, for furthering the use and development of the package.

John Conway, Univ. of California, Davis
Problems with this page? Send email. (Last update April 2012.)