Space-VLBI with RadioAstron: new correlator capabilities at MPIfR

TL;DR

This paper discusses the development of a new version of the DiFX correlator, called dra, at MPIfR, enabling space-based VLBI data correlation for RadioAstron and supporting ongoing AGN imaging projects.

Contribution

The paper introduces the dra version of DiFX, optimized for space-based antenna correlation in RadioAstron VLBI, and details its implementation on HPC at MPIfR.

Findings

Successfully managed correlation of space-based and ground-based antennas.

Enabled ongoing AGN imaging RadioAstron projects.

Demonstrated capabilities of the new correlator at MPIfR.

Abstract

DiFX is a correlator for VLBI data based on the FX architecture (first Fourier transform and then cross-multiply). DiFX is a free licensed software written in C++, developed and maintened by an international group of programmers. A new DiFX version (dra) has been developed at Max-Planck-Institut f\"ur Radioastronomie (MPIfR), in order to manage the correlation of a space-based antenna with ground stations. The dra version is running on the High Performance Computer cluster (HPC) in Bonn, and it is used for the data processing of the three AGN imaging RadioAstron Key Science Projects ongoing, based at the MPIfR.