HINODE/EIS SPECTROSCOPIC VALIDATION OF VERY HOT PLASMA IMAGED WITH THE SOLAR DYNAMICS OBSERVATORY IN NON-FLARING ACTIVE REGION CORES

Journal Article · Tue May 01 04:00:00 EDT 2012 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/750/1/L10· OSTI ID:22047865

Testa, Paola ^[1]; Reale, Fabio ^[2]

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1. Smithsonian Astrophysical Observatory, 60 Garden street, MS 58, Cambridge, MA 02138 (United States)
2. Dipartimento di Fisica, Universita di Palermo, Piazza del Parlamento 1, 90134 Palermo (Italy)

We use coronal imaging observations with the Solar Dynamics Observatory/Atmospheric Imaging Assembly (AIA), and Hinode/Extreme-ultraviolet Imaging Spectrometer (EIS) spectral data to explore the potential of narrowband EUV imaging data for diagnosing the presence of hot (T {approx}> 5 MK) coronal plasma in active regions. We analyze observations of two active regions (AR 11281, AR 11289) with simultaneous AIA imaging and EIS spectral data, including the Ca XVII line (at 192.8 A), which is one of the few lines in the EIS spectral bands sensitive to hot coronal plasma even outside flares. After careful co-alignment of the imaging and spectral data, we compare the morphology in a three-color image combining the 171, 335, and 94 A AIA spectral bands, with the image obtained for Ca XVII emission from the analysis of EIS spectra. We find that in the selected active regions the Ca XVII emission is strong only in very limited areas, showing striking similarities with the features bright in the 94 A (and 335 A) AIA channels and weak in the 171 A band. We conclude that AIA imaging observations of the solar corona can be used to track hot plasma (6-8 MK), and so to study its spatial variability and temporal evolution at high spatial and temporal resolution.

• OSTI ID: 22047865
• Journal Information: Astrophysical Journal Letters, Journal Name: Astrophysical Journal Letters Journal Issue: 1 Vol. 750; ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ASTRONOMY
ASTROPHYSICS
CALCIUM IONS
COLOR
COMPARATIVE EVALUATIONS
EMISSION SPECTROSCOPY
EXTREME ULTRAVIOLET RADIATION
EXTREME ULTRAVIOLET SPECTRA
GAMMA RADIATION
HOT PLASMA
MORPHOLOGY
RESOLUTION
SOLAR CORONA
SUN
VALIDATION
X RADIATION