QCD Uncertainties in Particle Spectra from Dark Matter Annihilation

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QCD Uncertainties on Particle Spectra from Dark Matter Annihilation

Authors: Simone Amoroso, Sascha Caron, Adil Jueid, Roberto Ruiz de Austri, and Peter Skands

If you use these tables, please cite:

S. Amoroso et al. arXiv: 1812.07424 [hep-ph], JCAP05(2019)007

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We provide the spectra of stable particles in dark matter annihilation, in the galactic region or beyond, in a tabulated form using PYTHIA8 version 8235. In addition to the central prediction, we estimate for the first time the QCD uncertainties both due to hadronization as well as to showering. The uncertainties on the spectra are provided in separate tables. A wide range of dark matter masses from 10 GeV to 100 TeV is covered. We consider 11 primary annihilation channels:

DM DM -> e+e-, mu+ mu-, tau tau, qq  (q=u,d,s), cc, bb, tt, WW, gg, ZZ, and hh.

Each file contains 13 columns: the dark matter mass, the fraction x (defined as the kinetic energy of the particle divided by the DM mass), and dN/dx for 11 primary channels. The provided tables correspond to the dN/dx of Standard Model stable particles, i.e. of photons, electron anti-neutrinos, muon anti-neutrinos and tau anti-neutrinos.

The work on the spectra of anti-protons is ongoing (please come back soon). We found a bug on the spectra of the positrons which we are working on it.

For each particle species, we provide twelve tables which can be found in zip format. The notation of the different tables is given below:

     1) The table corresponding to the central prediction for the spectra is denoted by 'AtProduction-Hadronization1-$TYPE.dat' with $TYPE=Nuel, Numu, Nuta, Ga which refers to the three flavours of neutrinos, and photons respectively.

     2) There are nine tables corresponding to the different variations of the light quark fragmentation function's parameters. These tables are denoted by 'AtProduction-Hadronization$h-$TYPE.dat' with h=2,..,10.

     3) The particle spectra corresponding to the variations of the shower evolution scale (mu_R) are denoted by 'AtProduction-Shower-Var$s-$TYPE.dat' with s=1,2  corresponds to 1/2 mu_R and 2 mu_R. 

IMPORTANT:

     i)    Uncertainty on the spectra, from hadronization, is obtained from the envelope of all the variations (including the central prediction).

     ii)   In the variations of the parton shower evolution scale, the parameters of the hadronization function are fixed to their central value.

     iii)  In principle, showering uncertainties are uncorrelated to hadronization uncertainties. To obtain the full uncertainty, one might combine those uncertainties in quadrature.

If you use the data on the site, please cite:

Simone Amoroso, Sascha Caron, Adil Jueid, Roberto Ruiz de Austri, Peter Skands, "Estimating QCD uncertainties in Monte Carlo event generators for gamma-ray dark matter searches," JCAP 05 (2019) 007, arXiv: 1812.07424.

In addition, if you use the data corresponding to shower uncertainties, please cite:

S. Mrenna and P. Skands, "Automated Parton-Shower Variations in Pythia 8,'' Phys. Rev. D 94 (2016) no.7, 074005, arXiv:1605.08352 [hep-ph].

Finally, please cite the paper of M. Cirelli et al. if you use their data for comparison or other tasks:

M.Cirelli, G.Corcella, A.Hektor, G.Hütsi, M.Kadastik, P.Panci, M.Raidal, F.Sala, A.Strumia, "PPPC 4 DM ID: A Poor Particle Physicist Cookbook for Dark Matter Indirect Detection'', JCAP 1103 (2011) 051, arXiv 1012.4515, Erratum: JCAP 1210 (2012) E01.

Contact: Adil Jueid <adil.hep@gmail.com>