An open-source, massively parallel code for non-LTE synthesis and inversion of spectral lines and Zeeman-induced Stokes profiles^⋆

¹ Instituto de Astrofísica de Canarias, Avda vía Láctea S/N, 38205 La Laguna, Tenerife Spain
e-mail: hsocas@iac.es
² Departamento de Astrofísica, Universidad de La Laguna 38205, La Laguna, Tenerife, Spain
³ Institute for Solar Physics, Dept. of Astronomy, Stockholm University, Albanova University Center, 10691 Stockholm, Sweden
⁴ Consejo Superior de Investigaciones Científicas, 28006 Madrid, Spain

Received: 26 August 2014
Accepted: 16 January 2015

Abstract

With the advent of a new generation of solar telescopes and instrumentation, interpreting chromospheric observations (in particular, spectropolarimetry) requires new, suitable diagnostic tools. This paper describes a new code, NICOLE, that has been designed for Stokes non-LTE radiative transfer, for synthesis and inversion of spectral lines and Zeeman-induced polarization profiles, spanning a wide range of atmospheric heights from the photosphere to the chromosphere. The code features a number of unique features and capabilities and has been built from scratch with a powerful parallelization scheme that makes it suitable for application on massive datasets using large supercomputers. The source code is written entirely in Fortran 90/2003 and complies strictly with the ANSI standards to ensure maximum compatibility and portability. It is being publicly released, with the idea of facilitating future branching by other groups to augment its capabilities.