The PHOX Family

This site aims to make available NLO FORTRAN codes allowing users to compute single and double inclusive large pt cross sections for reactions involving photons, hadrons and jets. The production of massive heavy quarks is not described by these codes in which a massless approximation is used.

These codes are event generators at the parton level and they are all built according to the same scheme. Please read the technical presentation page for a description of the method. This approach is flexible and allows the users to impose almost any experimental cuts, jet definitions, cross section definition via a histogram package. However, please read also the warnings about the limitations of the codes.

The program packages contain the MRST99, MRST01, CTEQ5 and CTEQ6 parton distributions for the proton. The photoproduction programs also include the AFG and the new AFG04 parton distributions for the photon. The option to link any parton distribution from the PDFLIB is also provided, but note that using the local grids is faster.

The fragmentation functions provided are

• Bourhis et al. for photons (Eur. Phys. J. C2 (1998) 529 )
• Bourhis et al. for charged hadrons (Eur. Phys. J. C19 (2001) 89 )
• Kniehl, Kramer, Pötter for hadrons (Nucl. Phys. B582 (2000) 514 )
• Binnewies, Kniehl, Kramer for hadrons ( Phys.Rev. D52 (1995) 4947; Phys.Rev. D53 (1996) 3573 )
• Kretzer for hadrons (Phys. Rev. D 62 (2000) 054001)

More information about the fragmentation functions can be found at the FF database page.
Simple interfaces are provided to allow the users to update distributions or to introduce new parametrizations.

It has been tried to make the input/output interface as user-friendly as possible. There is one general parameter-input file and a second optional one to define histograms.   (note that to create histograms, the PHOX codes use the PAW (HBOOK) histogram package of the CERNLIB. It is very likely that this tool is already installed on your system. If not, it can be downloaded from the CERN program library ). A perl script then automatically generates all necessary FORTRAN and executable files as well as directories for the output files. (For more details see the "README" of a particular program.)

Four families of codes are available on this site. By clicking on the relevant reaction you have access to the reaction's topical page (containing the corresponding README and useful references) and to the code to be downloaded.

• DIPHOX (acronym for DI-PHOton/hadron X sections, h_i denotes hadrons)
• h₁    h₂ ->       +  X

 
• h₁    h₂ ->      h₃   +  X

 
• h₁    h₂ ->   h₃    h₄   +  X

 
• JETPHOX (acronym for JET-PHOton/hadron X sections)
• h₁    h₂ ->     jet   +  X     and     h₁    h₂ ->    +  X  (see below)

 
• h₁    h₂ ->   h₃   jet   +  X     and     h₁    h₂ ->   h₃   +  X  (see below)

 
• h₁    h₂ ->   jet  jet    (under construction)

 
• EPHOX (acronym for Electron-Proton-initiated PHOton/hadron X sections, h₁ is typically a proton)
•   h₁ ->     jet   +  X     and       h₁ ->    +  X

 
•   h₁ ->   h₂    jet   +  X     and       h₁ ->   h₂   +  X

 
•   h₁ ->  jet   jet   +  X    (under construction)

 
• TWINPHOX (acronym for TWo-photon-INitiated PHOton/hadron X sections)
•   ->      jet    +  X    and   ->    +  X    (only with Frixione's isolation criterium)
•   ->   jet   jet    +  X    (under construction)

Enjoy the PHOX Family of Programs !

If one wants to compute inclusive cross section for photon/hadron production in hadronic collisions, one can use older programs INCNLO. These programs are faster than JETPHOX but they are purely inclusive, i. e. some experimental cuts, such as isolation cuts, cannot be taken into account.

• P. Aurenche
• T. Binoth
• M. Fontannaz
• J. Ph. Guillet
• G. Heinrich
• E. Pilon
• M. Werlen