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The Interface Region Imaging Spectrograph (IRIS)
Weber, M.; Scherrer, P. H.; Larsen, S. +85 more
The Interface Region Imaging Spectrograph (IRIS) small explorer spacecraft provides simultaneous spectra and images of the photosphere, chromosphere, transition region, and corona with 0.33 - 0.4 arcsec spatial resolution, two-second temporal resolution, and 1 km s−1 velocity resolution over a field-of-view of up to 175 arcsec × 175 arc…
The Helioseismic and Magnetic Imager (HMI) Vector Magnetic Field Pipeline: Overview and Performance
Liu, Yang; Leka, K. D.; Hayashi, Keiji +9 more
The Helioseismic and Magnetic Imager (HMI) began near-continuous full-disk solar measurements on 1 May 2010 from the Solar Dynamics Observatory (SDO). An automated processing pipeline keeps pace with observations to produce observable quantities, including the photospheric vector magnetic field, from sequences of filtergrams. The basic vector-fiel…
> 25 MeV Proton Events Observed by the High Energy Telescopes on the STEREO A and B Spacecraft and/or at Earth During the First ∼ Seven Years of the STEREO Mission
Christian, E. R.; Leske, R. A.; Labrador, A. W. +7 more
Using observations from the High Energy Telescopes (HETs) on the STEREO A and B spacecraft and similar observations from near-Earth spacecraft, we summarize the properties of more than 200 individual > 25 MeV solar proton events, some detected by multiple spacecraft, that occurred from the beginning of the STEREO mission in October 2006 to Dece…
Multi-Scale Gaussian Normalization for Solar Image Processing
Morgan, Huw; Druckmüller, Miloslav
Extreme ultra-violet images of the corona contain information over a wide range of spatial scales, and different structures such as active regions, quiet Sun, and filament channels contain information at very different brightness regimes. Processing of these images is important to reveal information, often hidden within the data, without introduci…
A Multi-Observatory Inter-Comparison of Line-of-Sight Synoptic Solar Magnetograms
Liu, Y.; Riley, P.; Hoeksema, T. +7 more
The observed photospheric magnetic field is a crucial parameter for understanding a range of fundamental solar and heliospheric phenomena. Synoptic maps, in particular, which are derived from the observed line-of-sight photospheric magnetic field and built up over a period of 27 days, are the main driver for global numerical models of the solar co…
Three-Dimensional Evolution of Flux-Rope CMEs and Its Relation to the Local Orientation of the Heliospheric Current Sheet
Kilpua, E. K. J.; Vourlidas, A.; Isavnin, A.
Flux ropes ejected from the Sun may change their geometrical orientation during their evolution, which directly affects their geoeffectiveness. Therefore, it is crucial to understand how solar flux ropes evolve in the heliosphere to improve our space-weather forecasting tools. We present a follow-up study of the concepts described by Isavnin, Vour…
Photometric and Thermal Cross-calibration of Solar EUV Instruments
Schrijver, C. J.; Testa, P.; Warren, H. +2 more
We present an assessment of the accuracy of the calibration measurements and atomic physics models that go into calculating the SDO/AIA response as a function of wavelength and temperature. The wavelength response is tested by convolving SDO/EVE and Hinode/EIS spectral data with the AIA effective area functions and by comparing the predictions wit…
Solar Dynamics Observatory and Hinode Observations of a Blowout Jet in a Coronal Hole
Young, P. R.; Muglach, K.
A blowout jet occurred within the south coronal hole on 9 February 2011 at 09:00 UT and was observed by the Atmospheric Imaging Assembly (AIA) and Helioseismic and Magnetic Imager (HMI) onboard the Solar Dynamics Observatory, and by the EUV Imaging Spectrometer (EIS) and X-Ray Telescope (XRT) onboard the Hinode spacecraft during coronal-hole monit…
Coronal Mass Ejections and Non-recurrent Forbush Decreases
Gopalswamy, N.; Mavromichalaki, H.; Papaioannou, A. +7 more
Coronal mass ejections (CMEs) and their interplanetary counterparts (interplanetary coronal mass ejections, ICMEs) are responsible for large solar energetic particle events and severe geomagnetic storms. They can modulate the intensity of Galactic cosmic rays, resulting in non-recurrent Forbush decreases (FDs). We investigate the connection betwee…
Comparative Study of MHD Modeling of the Background Solar Wind
Temmer, M.; Veronig, A. M.; Riley, P. +4 more
Knowledge about the background solar wind plays a crucial role in the framework of space-weather forecasting. In-situ measurements of the background solar wind are only available for a few points in the heliosphere where spacecraft are located, therefore we have to rely on heliospheric models to derive the distribution of solar-wind parameters in …