@Article{BalmacedaVourStenDalL:2018:HoReAr,
author = "Balmaceda, Laura A. and Vourlidas, Angelos and Stenborg, Guillermo
and Dal Lago, Alisson",
affiliation = "{George Mason University} and {The Johns Hopkins University
Applied Physics Laboratory} and {US Naval Research Laboratory} and
{Instituto Nacional de Pesquisas Espaciais (INPE)}",
title = "How Reliable Are the Properties of Coronal Mass Ejections Measured
from a Single Viewpoint?",
journal = "Astrophysical Journal",
year = "2018",
volume = "863",
number = "1",
pages = "e57",
month = "Aug.",
keywords = "catalogs, miscellaneous, Sun: coronal mass ejections (CMEs),
surveys.",
abstract = "We present an analysis of widths and kinematic properties of
coronal mass ejections (CMEs) obtained via a supervised image
segmentation algorithm, the CORonal SEgmentation Technique
(CORSET), on simultaneous observations from the two COR2
telescopes on the Solar Terrestrial Relations Observatory (STEREO)
mission, from 2007 May to 2014 September. The sample of 460 events
with measurements from two vantage points offers the opportunity
to test the accuracy and constraints of single-viewpoint
properties that underlie the bulk of CME research to date. In
addition, we examine the dependence of the properties on the
morphology of the events. The main findings are as follows. (1)
The radial speeds derived from different perspectives are in good
agreement with a relatively low intrinsic uncertainty of 39%. (2)
Projection effects are more important for determination of CME
width rather than for speed. (3) The expansion speeds depend on
CME morphology, with loop-type CMEs expanding twice as fast as
flux-rope CMEs, possibly underpinning the more explosive nature.
(4) Triangulations of CME speed and propagation direction are
optimal from viewpoints separated by 60°90°; e.g., between the
Lagrangian points L1 and L5 (or L4). (5) The projected speeds are
underestimated, on average, by at least 20% when compared to their
deprojected (triangulated) values. We also discuss in detail the
lessons learned from the application of the CORSET algorithm to
event tracking. Our findings should hopefully be a useful guide in
the use of (semi)automated algorithms for extraction of CME
physical parameters and in the interpretation of singleviewpoint
observations (likely to be the norm after the end of the STEREO
mission).",
doi = "10.3847/1538-4357/aacff8",
url = "http://dx.doi.org/10.3847/1538-4357/aacff8",
issn = "0004-637X and 1538-4357",
language = "en",
targetfile = "balmaceda-how.pdf",
urlaccessdate = "27 abr. 2024"
}