CRAFT - Cosmic Ray Analytical Fast Tool

CRAFT is a set of routines and subroutines that calculate particle acceleration at non-relativistic collisionless shocks, and is based on the fast semi-analytical approach developed by Amato & Blasi (2005), Caprioli, Amato & Blasi (2009a,b; 2010), Caprioli (2012), and Diesing and Caprioli (2021).

The solution of the cosmic ray diffusion-convection equation is completed with constantly updated microphysical prescriptions from kinetic simulations (Caprioli & Spitkovsky, 2014a,b,c; Caprioli, Pop, Spitkovsky 2015, Haggerty & Caprioli 2020, Caprioli et al. 2020).

Users have two ways of exploiting the potential of CRAFT:

  1. by using the routines that calculate CR spectra (slope, normalization and maximum energy) for given shock parameters;
  2. by running the full code that also integrates a supernova remnant (SNR) expansion in the uniform interstellar medium or in more complex environments.

The first choice allows, for instance, to embed refined CR physics in hydro/MHD simulations, also for astrophysical objects other than SNRs (e.g., interplanetary shocks, AGN lobes, galaxy clusters);
the second possibility will provide an out-of-the-box tool for an easy interpretation of broadband observations in the light of modern shock acceleration theory.

CRAFT is now getting an user-friendly python interface and is currently being augmented with more refined models for the expansion of shocks into different media.