Search Publications

Speckle interferometry with adaptive optics corrected solar data
DOI: 10.1051/0004-6361:200809894 Bibcode: 2008A&A...488..375W

Reardon, K.; von der Lühe, O.; Wöger, F.

Context: Adaptive optics systems are used on several advanced solar telescopes to enhance the spatial resolution of the recorded data. In all cases, the correction remains only partial, requiring post-facto image reconstruction techniques such as speckle interferometry to achieve consistent, near-diffraction limited resolution.
Aims: This stud…

2008 Astronomy and Astrophysics
Hinode 171
Flows in active region loops observed by Hinode EIS
DOI: 10.1051/0004-6361:20079087 Bibcode: 2008A&A...481L..49D

Del Zanna, G.

We aim to investigate the overall characteristics of coronal active region loops and their evolution. The Hinode database was searched for observations of active regions as they crossed the Sun centre. NOAA 10926 was selected. The morphology of this young active region did not significantly change over the course of a few days. Persistent redshift…

2008 Astronomy and Astrophysics
Hinode SOHO 151
Hinode observations of transverse waves with flows in coronal loops
DOI: 10.1051/0004-6361:20079340 Bibcode: 2008A&A...482L...9O

Wang, T. J.; Ofman, L.

Aims: We report the first evidence for transverse waves in coronal multithreaded loops with cool plasma ejected from the chromosphere flowing along the threads. These observations are good candidates for coronal seismology.
Methods: We analyzed observations made with Solar Optical Telescope (SOT) on board the Hinode satellite in the Ca II H li…

2008 Astronomy and Astrophysics
Hinode SOHO 133
Strong horizontal photospheric magnetic field in a surface dynamo simulation
DOI: 10.1051/0004-6361:20078998 Bibcode: 2008A&A...481L...5S

Schüssler, M.; Vögler, A.

Context: Observations with the Hinode spectro-polarimeter have revealed strong horizontal internetwork magnetic fields in the quiet solar photosphere.
Aims: We aim to interpret the observations with results from numerical simulations.
Methods: Radiative MHD simulations of dynamo action by near-surface convection are analyzed with respect t…

2008 Astronomy and Astrophysics
Hinode 115
Transient horizontal magnetic fields in solar plage regions
DOI: 10.1051/0004-6361:20079022 Bibcode: 2008A&A...481L..25I

Lites, B. W.; Ichimoto, K.; Ishikawa, R. +9 more

Aims:We report the discovery of isolated, small-scale emerging magnetic fields in a plage region with the Solar Optical Telescope aboard Hinode.
Methods: Spectro-polarimetric observations were carried out with a cadence of 34 s for the plage region located near disc center. The vector magnetic fields are inferred by Milne-Eddington inversion. …

2008 Astronomy and Astrophysics
Hinode 113
The intensity contrast of solar granulation: comparing Hinode SP results with MHD simulations
DOI: 10.1051/0004-6361:200809857 Bibcode: 2008A&A...484L..17D

Solanki, S. K.; Lagg, A.; Tsuneta, S. +5 more

Context: The contrast of granulation is an important quantity characterizing solar surface convection.
Aims: We compare the intensity contrast at 630 nm, observed using the Spectro-Polarimeter (SP) aboard the Hinode satellite, with the 3D radiative MHD simulations of Vögler & Schüssler (2007, A&A, 465, L43).
Methods: A synthetic im…

2008 Astronomy and Astrophysics
Hinode 110
Coronal magnetic field measurement using loop oscillations observed by Hinode/EIS
DOI: 10.1051/0004-6361:200810186 Bibcode: 2008A&A...487L..17V

Young, P. R.; Nakariakov, V. M.; Verwichte, E. +1 more

We report the first spectroscopic detection of a kink MHD oscillation of a solar coronal structure by the Extreme-Ultraviolet Imaging Spectrometer (EIS) on the Japanese Hinode satellite. The detected oscillation has an amplitude of 1 km s-1 in the Doppler shift of the FeXII 195 Å spectral line (1.3~MK), and a period of 296~s. The unique…

2008 Astronomy and Astrophysics
Hinode 101
Hinode EUV spectroscopic observations of coronal oscillations
DOI: 10.1051/0004-6361:200810263 Bibcode: 2008A&A...489L..49E

Erdélyi, R.; Taroyan, Y.

Context: Waves offer a unique opportunity to understand and diagnose the properties of the solar coronal plasma.
Aims: Hinode/EIS observations are analysed to detect wave and oscillatory motions in the solar corona.
Methods: The EIS observations were carried out using a selection of EUV lines. Hinode/XRT images are taken concurrently.

2008 Astronomy and Astrophysics
Hinode 95
Hinode XRT observations of a long-lasting coronal sigmoid
DOI: 10.1051/0004-6361:20079035 Bibcode: 2008A&A...481L..65M

Canfield, R. C.; McKenzie, D. E.

Aims:Coronal sigmoids are important sources of eruptions into interplanetary space, and a handful of models have been proposed to explain their characteristic S shape. However, the coronal X-ray images available to date have generally not had sufficient resolution to distinguish between these models. The goal of the present investigation is to det…

2008 Astronomy and Astrophysics
Hinode SOHO 89
Magnetic flux cancellation associated with a recurring solar jet observed with Hinode, RHESSI, and STEREO/EUVI
DOI: 10.1051/0004-6361:200810265 Bibcode: 2008A&A...491..279C

Young, P. R.; Mason, H. E.; Krucker, S. +7 more

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 E…

2008 Astronomy and Astrophysics
Hinode 88