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Prospino2

Prospino2 is a computer program which computes next-to-leading order cross sections for the production of supersymmetric particles at hadron colliders. The processes currently included are squark, gluino, stop, neutralino/chargino, and slepton pair production. We have also included the associated production of squarks with gluinos and of neutralinos/charginos with gluinos or squarks and most recently leptoquark pair production. This list is likely to be expanded, please come back and check. If you are interested in our so-called propaganda plots showing a sample of Prospino results, there are an LHC version, a 7 TeV LHC version, a 8 TeV LHC version, and a Tevatron version available.

This computer code is based on different projects with work done by many people over a long time - credits go to Wim Beenakker, Roland Höpker, Michael Krämer, Michael Spira and Peter Zerwas (in alphabetical order). The physics results are usually published, so you can cross check the results you get. As far as referencing goes, we will not publish a complete Prospino2 manual, because there are physics papers available for all processes. Instead, we would like you to reference the published papers for the respective processes. You can find a list of these papers below.

There has been a Fortran77 version of Prospino availabe for several years. The increased number of processes and the more complex set of input parameters have made it more convenient to migrate to Fortran90. The new code should run with any F90 compiler - for example the free gfortran, which even runs on your Macs. I have also tested the code with the F90 or F95 compilers by Intel, DEC, Portland Group and most recently NAG, where the latter was a serious pain.

Prospino2 can easily be linked to C++ programs, reads the Les Houches SUSY spectrum files and includes a set of easily accessible interfaces. Here you can see how a simple Prospino2 call looks. And this is the output for example for the SPS1a parameter point. For those of you who do not only want to produce supersymmetric particles, but also decay them again: you might be interested in the public code Sdecay, which can talk to Prospino2 through the Les Houches Accord.

Because of several requests let me sketch how Prospino2 approximately accounts for not mass-degenerate squarks in the final state. For historical reasons and to save CPU time mass degenerate squarks are hard-coded into the NLO code.
1- First, we compute the LO rates summing over the 5+5 light squark flavors, provided you set isquark1_in = isquark2_in = 0. If you want to only sum over the light 4+4 squark flavors you can easily change this in the code. The result is given as LO_ms in the output.
2- Then, we compute the LO and the NLO rates with an average squark mass. These numbers are given as LO and as NLO. The K factor in this output should be in an unspectacular range.
3- For the approximate NLO result with non-degenerate squarks we multiply the LO_ms rate with this K factor and give it out as NLO_ms. This is the best we can do in Prospino2, and we have checked that the result is fine within the theoretical uncertainties. For the completely general approach you can look at the MadGolem study.
4- The same approach we use in the case that the NLO calculation limits the differences in masses for example because of the on-shell subtraction. The K factor computed with limited mass splittings is used to scale the general leading order results LO_ms, giving NLO_ms. The executive summary of this is: unless you have a good reason to do it differently, use the NLO_ms prediction.

For the third generation Prospino2.1. allows you to treat the sbottom and stop channels differently. In this version there are also switches to compute the combined renormalization/factorization scale varation and allow for non-mass-genenerate light-flavor squarks.

Good luck, enjoy working with our program, please give me some feedback, and - hey - do us the favor and discover supersymmetry some time, if it is not too much trouble

Prospino2 news:
10/17/14	some issues with decoupling squarks and gluinos fixed (thanks to Stephan Lammel)
9/23/12	some old bugs which re-appeared fixed again (thanks to Andrea Ferroglia and Jay Chen)
3/26/12	bug for squarks and gluinos at 8 TeV fixed
11/20/11	version for Sanjay
11/3/11	scale variation for stops and sbottoms fixed (i.e. reduced)
	small bug in neutralino-gluino channel removed (thanks to Ahmed Ismail)
9/8/11	flavor choice in squark-gluino channels working (thanks to Alexander Mann)
3/16/11	recently introduced bug in stau pairs removed again (thanks to Sudeshna Banerjee and Mike Eads)
11/3/10	decoupling of gluino pairs corrected (thanks to Morten Dam Jorgensen)
10/4/10	errand line changed for light sbottoms (thanks to Sinan Kuday)
6/26/10	small problems/bugs removed, including light stops
	(thanks to Borge Gjelsten, Sezen Sekmen and Philippe Gris)
9/2/09	just cosmetics
8/24/09	more problems/bugs removed, including heavy masses
	(thanks to Michael Manhart, Are Raklev, Ingo Reisinger)
5/10/09	Prospino2.1 with some first bugs removed
	(thanks to Tom Rizzo and Sascha Caron)
10/13/08	Prospino2.1 complete version with many new features
	(thank you to Albert Villanova del Moral for checking the flavor sums)
4/16/08	Prospino2.1 beta version with independent sbottoms
1/2/06	associated leptoquark production included
9/1/05	numerically invisible typo in Prospino1 removed
7/21/05	problem with random numbers in ifort solved
10/22/04	neutralinos/charginos in Split-SUSY, leptoquark pairs, comments improved
7/17/04	parametrized Cteq5 linked, SLHA interface improved
5/18/04	all channels checked with SMadGraph at LO
5/10/04	Prospino2.0 beta version available, try it
Prospino references:
	squarks and gluinos stop pairs sbottom pairs (adapted from stops) neutralino and chargino pairs slepton pairs neutralino/chargino plus gluino neutralino/chargino plus squark or gluino
Other processes included:
	leptoquark pairs at Tevatron and LHC
	leptoquark plus lepton (adapt LQ charge via ifla_le!)
	charged Higgs plus top (private code, email before use)
	charged Higgs plairs (private code, email before use)

archive (of all the old and/or buggy versions),