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Time-Series Analysis of Supergranule Characteristics at Solar Minimum
Williams, Peter E.; Pesnell, W. Dean
Sixty days of Doppler images from the Solar and Heliospheric Observatory (SOHO) / Michelson Doppler Imager (MDI) investigation during the 1996 and 2008 solar minima have been analyzed to show that certain supergranule characteristics (size, size range, and horizontal velocity) exhibit fluctuations of three to five days. Cross-correlating parameter…
Velocities and Linewidths in the Network and Cell Interiors of a Polar Coronal Hole Compared with the Quiet Sun
Raju, K. P.; Bromage, B. J. I.
The relative Doppler velocities and linewidths in a polar coronal hole and the nearby quiet-Sun region have been obtained from the Solar and Heliospheric Observatory (SOHO)/Coronal Diagnostic Spectrometer (CDS) observations using emission lines originating at different heights in the solar atmosphere from the lower transition region (TR) to the lo…
How Many CMEs Have Flux Ropes? Deciphering the Signatures of Shocks, Flux Ropes, and Prominences in Coronagraph Observations of CMEs
Li, Y.; Lynch, B. J.; Howard, R. A. +1 more
We intend to provide a comprehensive answer to the question on whether all Coronal Mass Ejections (CMEs) have flux rope structure. To achieve this, we present a synthesis of the LASCO CME observations over the last 16 years, assisted by 3D MHD simulations of the breakout model, EUV and coronagraphic observations from STEREO and SDO, and statistics…
Propagation of Interplanetary Coronal Mass Ejections: The Drag-Based Model
Möstl, C.; Temmer, M.; Rollett, T. +9 more
We present the "Drag-Based Model" (DBM) of heliospheric propagation of interplanetary coronal mass ejections (ICMEs). The DBM is based on the hypothesis that the driving Lorentz force, which launches a CME, ceases in the upper corona and that beyond a certain distance the dynamics becomes governed solely by the interaction of the ICME and the ambi…
The Hinode Spectro-Polarimeter
Kubo, M.; Lites, B. W.; Ichimoto, K. +16 more
The joint Japan/US/UK Hinode mission includes the first large-aperture visible-light solar telescope flown in space. One component of the Focal Plane Package of that telescope is a precision spectro-polarimeter designed to measure full Stokes spectra with the intent of using those spectra to infer the magnetic-field vector at high precision in the…
The SWAP EUV Imaging Telescope Part I: Instrument Overview and Pre-Flight Testing
Berghmans, D.; Auchère, F.; Seaton, D. B. +17 more
The Sun Watcher with Active Pixels and Image Processing (SWAP) is an EUV solar telescope onboard ESA's Project for Onboard Autonomy 2 (PROBA2) mission launched on 2 November 2009. SWAP has a spectral bandpass centered on 17.4 nm and provides images of the low solar corona over a 54×54 arcmin field-of-view with 3.2 arcsec pixels and an imaging cade…
Solar Flare Prediction Using Advanced Feature Extraction, Machine Learning, and Feature Selection
Gallagher, Peter T.; Bloomfield, D. Shaun; Colak, Tufan +3 more
Novel machine-learning and feature-selection algorithms have been developed to study: i) the flare-prediction-capability of magnetic feature (MF) properties generated by the recently developed Solar Monitor Active Region Tracker (SMART); ii) SMART's MF properties that are most significantly related to flare occurrence. Spatiotemporal association a…
Heliolatitude and Time Variations of Solar Wind Structure from in situ Measurements and Interplanetary Scintillation Observations
McComas, D. J.; Bzowski, M.; Tokumaru, M. +2 more
The 3D structure of the solar wind and its evolution in time are needed for heliospheric modeling and interpretation of energetic neutral atoms observations. We present a model to retrieve the solar wind structure in heliolatitude and time using all available and complementary data sources. We determine the heliolatitude structure of solar wind sp…
The SP_PREP Data Preparation Package for the Hinode Spectro-Polarimeter
Lites, B. W.; Ichimoto, K.
The Hinode/Spectro-Polarimeter (SP) is the first space-borne precision spectro-polarimeter for the study of solar phenomena. It is primarily intended for measuring the solar photospheric vector magnetic field at high spatial and spectral resolution. This objective requires that the data are calibrated and conditioned to a high degree of precision.…
On-Orbit Degradation of Solar Instruments
Schmutz, W.; Berghmans, D.; Auchère, F. +38 more
We present the lessons learned about the degradation observed in several space solar missions, based on contributions at the Workshop about On-Orbit Degradation of Solar and Space Weather Instruments that took place at the Solar Terrestrial Centre of Excellence (Royal Observatory of Belgium) in Brussels on 3 May 2012. The aim of this workshop was …