Fan-shaped jets above the light bridge of a sunspot driven by reconnection

Abstract

We report on a fan-shaped set of high-speed jets above a strongly magnetized light bridge (LB) of a sunspot observed in the H$\alpha$ line. We study the origin, dynamics and thermal properties of the jets using high-resolution imaging spectroscopy in H$\alpha$ from the Swedish 1-m Solar Telescope and data from the Solar Dynamics Observatory and Hinode. The H$\alpha$ jets have lengths of 7-38 Mm, are impulsively accelerated to a speed of $\sim 100$ km/s close to photospheric footpoints in the LB, and exhibit a constant deceleration consistent with solar effective gravity. They are predominantly launched from one edge of the light bridge, and their footpoints appear bright in the H$\alpha$ wings. AIA data indicates elongated brightenings that are nearly co-spatial with the H$\alpha$ jets. We interpret them as jets of at least transition region temperatures. The magnetic field in the light bridge has a strength of $0.8-2$ kG and it is nearly horizontal. All jet properties are consistent with magnetic reconnection as the driver.

Accepted for publication in A&A

References in corpus (14)

• The Solar Optical Telescope for the Hinode Mission: An Overview
• CRISP Spectropolarimetric Imaging of Penumbral Fine Structure
• Hot Explosions in the Cool Atmosphere of the Sun
• Dynamic Fibrils are driven by Magnetoacoustic Shocks
• High Resolution Observations and Modeling of Dynamic Fibrils
• CRISPRED: A data pipeline for the CRISP imaging spectropolarimeter
• Jets in coronal holes: Hinode observations and 3D computer modelling
• Ellerman bombs at high resolution III. Simultaneous observations with IRIS and SST
• Vigorous convection in a sunspot granular light bridge
• Light Bridge in a Developing Active Region. I. Observation of Light Bridge and its Dynamic Activity Phenomena
• Light Bridge in a Developing Active Region. II. Numerical Simulation of Flux Emergence and Light Bridge Formation
• UV spectra, bombs, and the solar atmosphere
• Small-scale chromospheric jets above a sunspot light bridge
• Detection of opposite polarities in a sunspot light bridge: evidence of low-altitude magnetic reconnection

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• Three-minute Sunspot Oscillations Driven by Magnetic Reconnection in a Light Bridge
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