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An Investigation of the CME of 3 November 2011 and Its Associated Widespread Solar Energetic Particle Event
Long, D. M.; Harra, L. K.; Matthews, S. A. +2 more
Multi-spacecraft observations are used to study the in-situ effects of a large coronal mass ejection (CME) erupting from the farside of the Sun on 3 November 2011, with particular emphasis on the associated solar energetic particle (SEP) event. At that time both Solar Terrestrial Relations Observatory (STEREO) spacecraft were located more than 90 …
Bridging EUV and White-Light Observations to Inspect the Initiation Phase of a "Two-Stage" Solar Eruptive Event
Seaton, D. B.; Habbal, S. R.; Bain, H. M. +2 more
The initiation phase of coronal mass ejections (CMEs) is a very important aspect of solar physics, as these phenomena ultimately drive space weather in the heliosphere. This phase is known to occur between the photosphere and low corona, where many models introduce an instability and/or magnetic reconnection that triggers a CME, often with associa…
Calibrating Data from the Hinode/X-Ray Telescope and Associated Uncertainties
Reeves, Katharine K.; McKenzie, David E.; Saar, Steven H. +2 more
The X-Ray Telescope (XRT) onboard the Hinode satellite, launched 23 September 2006 by the Japan Aerospace Exploration Agency (JAXA), is a joint mission of Japan, the United States, and the United Kingdom to study the solar corona. In particular, XRT was designed to study solar plasmas with temperatures between 1 and 10 MK with ≈ 1″ pixels (≈ 2″ re…
Areas of Polar Coronal Holes from 1996 Through 2010
Karna, N.; Hess Webber, S. A.; Pesnell, W. D. +1 more
Polar coronal holes (PCHs) trace the magnetic variability of the Sun throughout the solar cycle. Their size and evolution have been studied as proxies for the global magnetic field. We present measurements of the PCH areas from 1996 through 2010, derived from an updated perimeter-tracing method and two synoptic-map methods. The perimeter-tracing m…
Coronal-Temperature-Diagnostic Capability of the Hinode/ X-Ray Telescope Based on Self-consistent Calibration. II. Calibration with On-Orbit Data
Weber, M.; Winebarger, A.; Kano, R. +4 more
The X-Ray Telescope (XRT) onboard the Hinode satellite is an X-ray imager that observes the solar corona with the capability of diagnosing coronal temperatures from less than 1 MK to more than 10 MK. To make full use of this capability, Narukage et al. (Solar Phys.269, 169, 2011) determined the thickness of each of the X-ray focal-plane analysis f…
Characterization of the Turbulent Magnetic Integral Length in the Solar Wind: From 0.3 to 5 Astronomical Units
Dasso, S.; Matthaeus, W. H.; Weygand, J. M. +1 more
The solar wind is a structured and complex system, in which the fields vary strongly over a wide range of spatial and temporal scales. As an example, the turbulent activity in the wind affects the evolution in the heliosphere of the integral turbulent scale or correlation length [λ], usually associated with the breakpoint in the turbulent-energy s…
Imaging Observations of X-Ray Quasi-periodic Oscillations at 3 - 6 keV in the 26 December 2002 Solar Flare
Ning, Zongjun
Quasi-periodic oscillations in soft X-rays (SXR) are not well known due to the instrument limitations, especially the absence of imaging observations of SXR oscillations. We explore the quasi-periodic oscillations of SXR at 3 - 6 keV in a solar flare observed by the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) on 26 December 2002.…
Resolving Differences in Absolute Irradiance Measurements Between the SOHO/CELIAS/SEM and the SDO/EVE
Judge, D. L.; Didkovsky, L. V.; Wieman, S. R.
The Solar EUV Monitor (SEM) onboard SOHO has measured absolute extreme ultraviolet (EUV) and soft X-ray solar irradiance nearly continuously since January 1996. The EUV Variability Experiment (EVE) on SDO, in operation since April of 2010, measures solar irradiance in a wide spectral range that encompasses the band passes (26 - 34 nm and 0.1 - 50 …
The Association of Solar Flares with Coronal Mass Ejections During the Extended Solar Minimum
Lemen, J. R.; Aschwanden, M. J.; Nitta, N. V. +3 more
We study the association of solar flares with coronal mass ejections (CMEs) during the deep, extended solar minimum of 2007 - 2009, using extreme-ultraviolet (EUV) and white-light (coronagraph) images from the Solar Terrestrial Relations Observatory (STEREO). Although all of the fast (v>900 km s−1), wide (θ>100∘) CMEs a…
How Can Active Region Plasma Escape into the Solar Wind from Below a Closed Helmet Streamer?
Pick, M.; Mandrini, C. H.; van Driel-Gesztelyi, L. +6 more
Recent studies show that active-region (AR) upflowing plasma, observed by the EUV-Imaging Spectrometer (EIS) onboard Hinode, can gain access to open-field lines and be released into the solar wind (SW) via magnetic-interchange reconnection at magnetic null-points in pseudo-streamer configurations. When only one bipolar AR is present on the Sun and…