SPheno is the abreviation of Supersymetric Phenomenology. The code from Werner Porod, which is available at http://spheno.hepforge.org/ calculates any SUSY spectrum using low energy data and a user supplied high scale model as input.

Installing SPheno

Note: the information below refers to the SPheno version from 2010 (or even earlier?), but the basic procedure to install and run it is the same today.

The current version (SPheno3.0.beta) can be downloaded as zipped tarball from Werner Porod's home page. If you intend to create a GMSB spectrum it will fail to decay the neutralinos. In this case you can download the attached, moified version: SPheno3.0.beta.tar.gz Just create a new directory and unpack the tarball

$ mkdir SPheno
$ tar -xvzf SPheno.3.0.beta.tar.gz

This will create the directory SPheno3.0.beta. The documentation of SPheno is in the /doc subdirectory.

To install the package just type

$ cd SPheno3.0.beta
$ gmake

and you will get an executable that can be run with

$ ./bin/SPheno

This will create a SPheno.out and a SPheno.spc in SUSY Les Houche Accord format which can be passed to any event generator, e.g. Whizard.

Creating a Les Houche Accord File

To create your SUSY point, adopt the LesHouche.in file you find in the SPheno3.0.beta directory accordingly. Here you can chose the SUSY breaking scenario you prefer

Block MODSEL                 # Select model
#1    1                      # mSugra   
 1    2                      # mGMSB
#1    3                      # AMSB

The next block contains standardmodel parameters I would rather not touch:

Block SMINPUTS               # Standard Model inputs
 2   1.166390E-05       # G_F, Fermi constant
 3   1.172000E-01       # alpha_s(MZ) SM MSbar
 4   9.118760E+01       # Z-boson pole mass
 5   4.200000E+00       # m_b(mb) SM MSbar
 6   1.743000E+02       # m_top(pole)
 7   1.777000E+00       # m_tau(pole)

But the third block will define your specific parameter point and thus has to be adopted:

# for GMSB:
Block MINPAR            # Input parameters
 1   1.100000E+05       # Lambda in GeV
 2   2.400000E+05       # M_mess in GeV
 3   3.000000E+00       # tanb 
 4   -1                 # sign(mu)
 5   1                  # n_5
 6   24                 # c_grav

# for mSugra:
Block MINPAR                 # Input parameters
 1   7.000000E+01       # m0
 2   2.500000E+02       # m12
 3   1.000000E+01       # tanb
 4   1                  # sign(mu)
 5  -3.000000E+02       # A0

Once you have set all values properly, just run ./bin/SPheno and check wether the masses and branching ratios in the output files are as expected.

SPheno (last edited 2015-02-20 18:39:13 by AnnikaVauth)