Luca Maccione

CRPropa 2.0 -- a Public Framework for Propagating High Energy Nuclei, Secondary Gamma Rays and Neutrinos

Version 2.0 of CRPropa 1 is public software to model the extra-galactic propagation of ultra-high energy nuclei of atomic number Z 26 through structured magnetic fields and ambient photon backgrounds taking into account all relevant particle interactions. CRPropa covers the energy range 6 10 16 < E=eV < A 10 22 where A is the nuclear mass number. CRPropa can also be used to track secondary -rays and neutrinos which allows the study of their link with the charged primary nuclei ‐ the so called multi-messenger connection. After a general introduction we present several sample applications of current interest concerning the physics of extragalactic ultra-high energy radiation.

Constraints on particle dark matter from cosmic-ray antiprotons

Cosmic-ray antiprotons represent an important channel for dark matter indirect-detection studies. Current measurements of the antiproton flux at the top of the atmosphere and theoretical determinations of the secondary antiproton production in the Galaxy are in good agreement, with no manifest deviation which could point to an exotic contribution in this channel. Therefore, antiprotons can be used as a powerful tool for constraining particle dark matter properties. By using the spectrum of PAMELA data from 50 MV to 180 GV in rigidity, we derive bounds on the dark matter annihilation cross section (or decay rate, for decaying dark matter) for the whole spectrum of dark matter annihilation (decay) channels and under different hypotheses of cosmic-rays transport in the Galaxy and in the heliosphere. For typical models of galactic propagation, the constraints are strong, setting a lower bound on the dark matter mass of a thermal relic at about 40–80 GeV for hadronic annihilation channels. These bounds are enhanced to about 150 GeV on the dark matter mass, when large cosmic-rays confinement volumes in the Galaxy are considered, and are reduced to 3–4 GeV for annihilation to light quarks (no bound for heavy-quark production) when the confinement volume is small. Boundsmorexa0» for dark matter lighter than few tens of GeV are due to the low energy part of the PAMELA spectrum, an energy region where solar modulation is relevant: to this aim, we have implemented a detailed solution of the transport equation in the heliosphere, which allowed us not only to extend bounds to light dark matter, but also to determine the uncertainty on the constraints arising from solar modulation modelling. Finally, we estimate the impact of soon-to-come AMS-02 data on the antiproton constraints.«xa0less

Cosmic ray electrons, positrons and the synchrotron emission of the Galaxy: consistent analysis and implications

A multichannel analysis of cosmic ray electron and positron spectra and of the diffuse synchrotron emission of the Galaxy is performed by using the DRAGON code. This study is aimed at probing the interstellar electron source spectrum down to E 1GeV and at constraining several propagation parameters. We find that above 4GeV the e− source spectrum is compatible with a power-law of index ~ 2.5. Below 4GeV instead it must be significantly suppressed and the total lepton spectrum is dominated by secondary particles. The positron spectrum and fraction measured below a few GeV are consistently reproduced only within low reacceleration models. We also constrain the scale-height zt of the cosmic-ray distribution using three independent (and, in two cases, original) arguments, showing that values of zt 2kpc are excluded. This result may have strong implications for particle dark matter searches.

PAMELA and AMS-02

The PAMELA collaboration recently released the

e^+

{e}^{+}

and

absolute spectrum between 1 and 300 GeV in addition to the positron fraction and the

e^-

{e}^{ensuremath{-}}

spectra are reproduced by three-dimensional cosmic-ray modeling

spectrum previously measured in the same period. We use the newly developed three-dimensional upgrade of the dragon package to model those data. This code allows us to consider a realistic spiral-arm source distribution in the Galaxy, which impacts the high-energy shape of the propagated spectra. At low energy we treat solar modulation with the HelioProp code and compare its results with those obtained using the usual force-field approximation. We show that all PAMELA data sets can be consistently, and accurately, described in terms of a standard background on top of which a charge symmetric

Violations of Lorentz invariance in the neutrino sector: an improved analysis of anomalous threshold constraints

{e}^{+}+{e}^{ensuremath{-}}

Dark matter searches with cosmic antideuterons: status and perspectives

extra component with harder injection spectrum is added; this extra contribution is peaked at