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Applying an Automatic Image-Processing Method to Synoptic Observations
Tlatov, Andrey G.; Vasil'eva, Valeria V.; Makarova, Valentina V. +1 more
We used an automatic image-processing method to detect solar-activity features observed in white light at the Kislovodsk Solar Station. This technique was applied to automatically or semi-automatically detect sunspots and active regions. The results of this automated recognition were verified with statistical data available from other observatorie…
A New Sigmoid Catalog from Hinode and the Solar Dynamics Observatory: Statistical Properties and Evolutionary Histories
DeLuca, E. E.; Savcheva, A. S.; McKillop, S. C. +2 more
We present a new sigmoid catalog covering the duration of the Hinode mission and the Solar Dynamics Observatory (SDO) until the end of 2012. The catalog consists of 72 mostly long-lasting sigmoids. We collect and make available all X-ray and EUV data from Hinode, SDO, and the Solar TErrestrial RElations Observatory (STEREO), and we determine the s…
Coronal Holes in Solar Cycles 21 to 23
Tlatov, A.; Tavastsherna, K.; Vasil'eva, V.
We present identifications of coronal holes (CHs) from observations in the He I 10 830 Å line made at Kitt Peak Observatory (from 1975 to 2003) and in the EUV 195 Å wavelength with SOHO/EIT (from 1996 to 2012). To determine whether a feature is a CH we have developed semi-automatic techniques for delineating CH borders on synoptic charts and for s…
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.…