HOP list   Monthly Events

HINODE Operation Plan (HOP)

accepted on


 HOP No.

 HOP title

HOP 0212

Dynamic events in the chromosphere of the Quiet Sun: RBEfs and Swirls

plan term


@ @


 name : Scullion, Erdelyi, Fedun @  e-mail : eamonms[at]astro.uio.no

contact person in HINODE team

 name : Culhane @  e-mail : jlc[at]mssl.ucl.ac.uk

 abstract of observational proposal
The connection of the coronal magnetic field with the solar surface through the chromosphere leads to interesting dynamics in the chromospheric structure. It is highly likely that the origin of the fast wind/stream of outflowing plasma lies within small-scale dynamic processes which appear continuously and frequently in the chromosphere of coronal holes and the quiet Sun, namely, spicules and swirls.

Over the past decade there has been a resurgence in the study of spicules. Recent observations have lead us to conclude that there are two distinct varieties of spicule, namely, slower type-I (i.e. mottles, dynamic fibrils, Halpha spicules etc.) and faster type-II (RBEs: Rapid Blue-shift Excursions on-disk). RBEs are observed in both Halpha 6563 A and Ca ii 8542 A wavelength channels. Such events dominate the dynamics of the chromosphere in coronal holes and quiet Sun. Joint SDO (Solar Dynamics Observatory: 2010) and Hinode observations have revealed that fast spicules are the source of hot plasma channelling into the corona. Understanding these small-scale jet-like structures of the chromosphere allows us to address the heating of the corona and the acceleration of the fast solar wind in coronal holes. A statistical approach to RBE studies can tell how much much energy they contribute to coronal heating which remains an open question. With a statistical approach to RBEs we can place constraints upon the mass outflow rate with respect to their contribution to the fast solar wind.

Recently, vortex-driven swirl structures have been discovered in the solar chromosphere. Chromospheric swirls are believed to be formed by rapidly rotating magnetic flux structures whichform as a direct result of the vortex flows in the photosphere. We consider that these structures may, also, be efficiently channelling energy from the photosphere through to the solar corona. These swirl structures may have a corresponding response in the atmospheric layers above. Not
a lot is currently known about swirls in the scientific literature. More statistics concerning disk centre swirls (i.e. avoiding any projection issues) in the Quiet Sun (i.e. ideal for observing swirls and to minimize any line blending issues with Hinode/EIS) are required.

 request to SOT
No request

 request to XRT
No request

 request to EIS
The study is intended to be run exactly on the disk centre in Quiet Sun, plage or equatorial Coronal hole conditions to search for rapidly evolving, cool events such as swirls and spicules.

Run DRW001_HI_BRT_V3 (ID # 487) with 12 repeats for one hour of observing. Precede and follow with context study IUU_SLOT_488x512 (ID # 378).

The prime one hour slot each day is from 09:00 UT to 10:00 UT.

 other participating instruments

Time period of proposed observations:

Our time request is based upon our (accepted) coordinated observational campaign with the CRISP (CRisp Imaging Spectro-Polarimeter) instrument at the 1-m Swedish Solar Telescope (SST) on La Palma, Canary Isl. We have 14 days of awarded time on this instrument in the period 20th June 2012 until 3rd July 2012. We would like to request coordinated Hinode/EIS data for as much of this period as possible. It will be most convenient to have Hinode/EIS support between the hours of 08:00 UT and 11:00 UT. Short interruptions will be allowed over the observing period.

With the continuous support of full-disk, space-based observations such as with SDO at our disposal the alignment between CRISP/SST in the chromosphere and hotter channels is certainly achievable. Ideally, we would like to incorporate into this campaign the Hinode/EIS instrument which can provide the necessary spectroscopic information in order to bridge the connections between the chromospheric structure and the corona. As a result, we could very precisely diagnose the dynamics of the quiet Sun atmosphere across a very broad range of the EM spectrum and in height from the solar surface.

HOP list   Monthly Events