Skip to content
Home
About Us
Resources
Profiles Metrics
Authors Directory
Institutions Directory
Top Authors
Top Institutions
Top Sponsors
AI Digest
Contact Us
Menu
Home
About Us
Resources
Profiles Metrics
Authors Directory
Institutions Directory
Top Authors
Top Institutions
Top Sponsors
AI Digest
Contact Us
Home
About Us
Resources
Profiles Metrics
Authors Directory
Institutions Directory
Top Authors
Top Institutions
Top Sponsors
AI Digest
Contact Us
Menu
Home
About Us
Resources
Profiles Metrics
Authors Directory
Institutions Directory
Top Authors
Top Institutions
Top Sponsors
AI Digest
Contact Us
Publication Details
AFRICAN RESEARCH NEXUS
SHINING A SPOTLIGHT ON AFRICAN RESEARCH
earth and planetary sciences
The growth, polarization, and motion of the radio afterglow from the giant flare from SGR 1806-20
Astrophysical Journal, Volume 634, No. 1 II, Year 2005
Notification
URL copied to clipboard!
Description
The extraordinary giant flare (GF) of 2004 December 27 from the soft gamma repeater SGR 1806-20 was followed by a bright radio afterglow. We present an analysis of VLA observations of this radio afterglow from SGR 1806-20, consisting of previously reported 8.5 GHz data covering days 7-20 after the GF, plus new observations at 8.5 and 22 GHz from day 24 to 81. We detect motion in the flux centroid of the afterglow, at an average velocity of (0.26 ± 0.03)c (assuming a distance of 15 kpc) at a position angle of -45°. This motion, in combination with the growth and polarization measurements, suggests an asymmetric outflow, mainly from one side of the magnetar. We find a deceleration in the expansion, from ∼9 to <5 mas day-1. The time of deceleration is roughly coincident with the rebrightening in the radio light curve, as expected to result when the ejecta from the GF sweeps up enough of the external medium and transitions from a coasting phase to the Sedov-Taylor regime. The radio afterglow is elongated and maintains a 2 : 1 axis ratio with an average position angle of -40° (north through east), oriented perpendicular to the average intrinsic linear polarization angle. © 2005. The American Astronomical Society. All rights reserved.
Authors & Co-Authors
Taylor, Gregory B.
United States, Stanford
Kavli Institute for Particle Astrophysics and Cosmology
United States, Socorro
National Radio Astronomy Observatory Socorro
Gelfand, Joseph D.
United States, Cambridge
Harvard-smithsonian Center for Astrophysics
Gaensler, B. M.
United States, Cambridge
Harvard-smithsonian Center for Astrophysics
Granot, Jonathan
United States, Stanford
Kavli Institute for Particle Astrophysics and Cosmology
Kouveliotou, Chryssa K.
United States, Huntsville
Nasa Marshall Space Flight Center
Fender, Robert P.
United Kingdom, Southampton
University of Southampton
Ramírez-Ruiz, Enrico
United States, Princeton
Institute for Advanced Study
Garrett, Michael A.
Netherlands, Dwingeloo
Joint Institute for Vlbi in Europe
Wijers, Ralph A.M.J.
Netherlands, Amsterdam
Universiteit Van Amsterdam
Statistics
Citations: 39
Authors: 9
Affiliations: 9
Identifiers
Doi:
10.1086/491648
ISSN:
0004637X