HOP 0016

HINODE Operation Plan (HOP)

accepted on

24-May-07

HOP No.

HOP title

HOP 0016

Sac Peak campaign； Dunn Solar Telescope: morphological and dynamical behavior of the magnetic field in the QS chromosphere

plan term

2007/05/24-2007/05/30

proposer

name :

T. Berger

e-mail :

berger[at]lmsal.com

contact person in HINODE team

name :

T. Berger

e-mail :

berger[at]lmsal.com

abstract of observational proposal

The primary goal of our observation campaign is a detailed investigation of the morphological and dynamical behavior of the magnetic field in the quiet Sun chromosphere. The variation on short timescales (a few 10 s) and small spatial scales (down to 100 km) is of particular interest. The resulting data will be compared with synthetic data from numerical 3D simulations. These simulations, which have been produced with the state-of-the-art radiation magnetohydrodynamics
code CO5BOLD, exhibit two dynamically distinct regimes in the atmosphere. In the photosphere magnetic fields are advected with the fluid flow towards intergranular lanes. Consequently they form field concentrations in the lanes (e.g. visible in the G-band) and voids in/above the granule centres. In contrast to the highly structured lower layers, the chromospheric field is much more homogeneous but varies much faster – on time scales of less than one minute. Waves are excited as a result of convective overshooting and oscillations in the low/middle photosphere and propagate upwards into the chromosphere. The properties of such waves are of crucial importance for the ongoing controversy about the relevant heating mechanism for the quiet Sun’s chromosphere. Our secondary objective is thus the detection of such waves and their photospheric excitation sources. The comparison between models and observations is not only helpful for the interpretation of the latter but also serves as necessary validation check of the models.

pointing: disk center; no AR in FOV

request to SOT

SOT/SP:Dynamicsmode,　3scans　of　adjacent　strips　in　the　inter-network,　quiet　Sun　(FOV:31.6”32”=4.8”32”,　cadence:318s=56s)　
SOT/BFI:　430nm(Gband),　needed　for　the　co-alignment　with　the　DST　data　(cadence:20s)
SOT/NFI:　630nm,　measurements　of　the　photospheric　magnetic　field　(cadence:20s)

other participating instruments

Dunn Solar Telescope (DST) at the National Solar Observatory, Sacramento Peak, USA. We plan to use the Interferometric Bidimensional Spectrometer (IBIS) in the vector polarimetric mode (Ca II IR line/Halpha) in combination with simultaneous
filtergrams (G-band, Halpha).

remarks

Observing hours: 15:00-22:00UT