Likelihoods for indirect dark matter searches with gamma rays

  Author: Christoph Weniger <>
  Created: Jul 2014
  Major updates: Jan 2016, Sep 2016
  Version: 1.0.0 (May 2017)


gamLike has been tested with GNU C and C++ compilers (5.2.1), and requires gsl
libraries for some of the integration routines.  Adjust the flags in the
Makefile, run


and the static and shared gamLike libraries are generated in the ./lib folder.


The relevant interface is defined in include/gamLike.hpp (with another Fortran
friendly version in include/gamLike_C.hpp).  Tests and examples in Python can
be found in scripts/

List of implemented likelihoods

- FermiLAT_dSph_2013: Combined Fermi pass7 dSph limits (2013)
  Ackermann, M. et al. 2014, Phys. Rev. D, 89, 042001 (arXiv:1310.0828)
  (15 dwarfs, profiling over J-value uncertainties)

- FermiLAT_dSph_2015: Combined Fermi pass8 dSph limits (2015)
  Ackermann, M. et al. 2015, Phys. Rev. Lett. 115 (2015) 23, 231301 (arXiv:1503.02641)
  (15 dwarfs, profiling over J-value uncertainties)

- Fermi GeV excess likelihood
  based on Calore, Cholis and CW, JCAP 1503 (2015) 038 (arXiv:1409.0042)
  (including estimate for covariance of foreground systematics)
  - FermiLAT_GC_CaloreA_2014: without J-value uncertainties (as in JCAP 1503 (2015) 038)
  - FermiLAT_GC_CaloreB_2014: marginalized J-value uncertainites (as in Phys.Rev. D91 (2015) 6, 063003)
  - FermiLAT_GC_Achterberg_2015: marginalized J-value uncertainties & 10% HEP systematics (as in JCAP 1508 (2015) 08, 006)
  - FermiLAT_GC_CaloreExt_2014: with J-value calculated for input profile.

- CTA projections
  based on Silverwood et al., JCAP 1503 (2015) 03, 055 (arXiv:1408.4131)
  (including 1% instr. systematics, for 100h observations, no J-value

- HESS-I Halo analysis
  based on Abramowski+ 2011, Phys. Rev. Lett. 106 (2011) 161301 (arXiv:1103.3266)
  - HESS_Abramowski_integrated: Reproduces PRL results (just one energy bin)
  - HESS_Abramowski_binned: Takes into account energy bins as shown in PRL
    (is more accurate for spectra with features)

- The dark matter profiles adopted for the individual likelihoods are the ones
  that were used in the original publications.
- The Milky Way profile can be set externally for some of the likelihoods.
- The effects of energy dispersion are currently not implemented for any of the
  experiments.  This is approximately OK for spectra like bb or mu+ mu-, but
  miserably fails for gamma-ray lines or virtual internal Bremsstrahlung.

How to cite

When using this package, please cite the relevant original experimental papers
as well as the GAMBIT DarkBit paper (arXiv:1705.xxxxx), which is the release
paper for this package.