Comparison of Hinode/XRT and RHESSI detection of hot plasma in the non-flaring solar corona

TL;DR

This study compares Hinode/XRT and RHESSI observations of the non-flaring solar corona, finding consistent evidence of a minor hot plasma component around 6.8-6.9 log T, with acceptable discrepancies.

Contribution

It provides a direct comparison of XRT and RHESSI data for the same active region, demonstrating their compatibility in detecting hot plasma components.

Findings

Both instruments detect a minor hot plasma component at log T ~ 6.8-6.9.

Discrepancies between XRT and RHESSI are within a factor of a few.

Cross-consistency supports the reliability of multi-instrument plasma diagnostics.

Abstract

We compare observations of the non-flaring solar corona made simultaneously with Hinode/XRT and with RHESSI. The analyzed corona is dominated by a single active region on 12 November 2006. The comparison is made on emission measures. We derive emission measure distributions vs temperature of the entire active region from multifilter XRT data. We check the compatibility with the total emission measure values estimated from the flux measured with RHESSI if the emission come from isothermal plasma. We find that RHESSI and XRT data analyses consistently point to the presence of a minor emission measure component peaking at log T ~ 6.8-6.9. The discrepancy between XRT and RHESSI results is within a factor of a few and indicates an acceptable level of cross-consistency.