Magnetic flux cancellation associated with a recurring solar jet observed with Hinode, RHESSI, and STEREO/EUVI^*

¹ Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, Wilberforce Road, Cambridge CB3 0WA, UK e-mail: c.chifor@damtp.cam.ac.uk

² Kwasan and Hida Observatory, Kyoto University, Yamashina, Kyoto 607-8471, Japan
³ Department of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK
⁴ STFC Rutherford Appleton Laboratory, Chilton, Didcot, Oxfordshire OX11 0QX, UK
⁵ Mullard Space Science Laboratory, University College London, Holmbury St. Mary, Dorking, Surrey RH5 6NT, UK 

⁶ Space Science Laboratory, University of California at Berkeley, Berkeley, CA 94720-7450, USA 

⁷ Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshindai, Sagamihara, Kanagawa, 229-8510, Japan
⁸ Department of Earth and Planetary Science, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan


Received: 26 May 2008
Accepted: 26 August 2008

Abstract

Aims. We study the physical properties of a recurring solar active region jet observed in X-rays and extreme-ultraviolet (EUV).

Methods. Multi-wavelength data from all three instruments on board Hinode were analysed. X-ray imaging and spectroscopy of the microflaring emission associated with the jets was performed with the Reuven Ramaty High Energy Spectroscopic Imager (RHESSI). Associated EUV jets were observed with the Sun Earth Connection Coronal and Heliospheric Investigation (SECCHI)/Extreme Ultraviolet Imager (EUVI) on board STEREO.

Results. We found a correlation between recurring magnetic flux cancellation close to a pore, the X-ray jet emission, and associated Ca II H ribbon brightenings. We estimated the lower limit for the decrease in magnetic energy associated with the X-ray jet emission at 3 10²⁹ erg. The recurring plasma ejection was observed simultaneously at EUV and X-ray temperatures, associated with type III radio bursts and microflaring activity at the jet footpoint.

Conclusions. The recurring jet (EUV and X-ray) emissions can be attributed to chromospheric evaporation flows due to recurring coronal magnetic reconnection. In this process, the estimated minimum loss in the magnetic energy is sufficient to account for the total energy required to launch the jet.