The SLED project and the dynamics of coronal flux ropes

TL;DR

This paper introduces the SLED instrument designed for high-precision imaging spectroscopy of coronal plasma dynamics, demonstrated through simulations of siphon flows in coronal flux ropes to enhance understanding of solar phenomena.

Contribution

The paper presents the design and capabilities of the new SLED instrument, including its innovative MSDP technique and its application to observing coronal flux rope dynamics.

Findings

Simulated observations of siphon flows demonstrate SLED's potential for high-precision Doppler measurements.

SLED can measure Doppler shifts up to 150 km/s with 50 m/s accuracy.

The instrument is optimized for studying fast solar events like flares and CMEs.

Abstract

Investigations of the dynamics of the hot coronal plasma are crucial for understanding various space weather phenomena and making in-depth analyzes of the global heating of the solar corona. We present here numerical simulations of observations of siphon flows along loops (simple semi-circular flux ropes) to demonstrate the capabilities of the Solar Line Emission Dopplerometer (SLED), a new instrument under construction for imaging spectroscopy. It is based on the Multi-channel Subtractive Double Pass (MSDP) technique, which combines the advantages of filters and slit spectrographs. SLED will observe coronal structures in the forbidden lines of FeX 637.4 nm and FeXIV 530.3 nm, and will measure Doppler shifts up to 150 km/s at high precision (50 m/s) and cadence (1 Hz). It is optimized for studies of the dynamics of fast evolving events such as flares or Coronal Mass Ejections (CMEs), as well as for the detection of high-frequency waves. Observations will be performed with the coronagraph at Lomnicky Stit Observatory (LSO), and will also occur during total solar eclipses as SLED is a portable instrument.