资源环境科技发展态势分析平台

We present direct and scaled comparisons between laboratory and in situ space observations of magnetic reconnection with a guide field, comparing results from the Magnetospheric Multiscale Mission and the Magnetic Reconnection eXperiment (MRX). While Magnetospheric Multiscale Mission observations obtain high-resolution and fully kinetic data, MRX observations fully cover the 2-D reconnection plane near the current sheet, removing uncertainties in situating the measurements compared to the reconnection region. Through scaling transformations, we show a quantitative agreement in magnetic field and current density profiles, which agree within a factor of 2 from each other. The introduction of the guide field causes the energy conversion J . E in the current sheet to be dominated by J(vertical bar vertical bar)E(vertical bar vertical bar) in both cases. However, parallel electric fields reported by recent spacecraft crossings are significantly (5-10 times) larger than values obtained on MRX, highlighting an important issue for understanding energy conversion by reconnection.