Expansion of SN 1993J
J. M. Marcaide (1),
A. Alberdi,
E. Ros,
P. Diamond,
I. I. Shapiro,
J. C. Guirado,
D. L. Jones,
T. P. Krichbaum,
F. Mantovani,
R. A. Preston,
A. Rius,
R. T. Schilizzi,
C. Trigilio,
A. R. Whitney,
A. Witzel
A sequence of images from very long baseline interferometry shows
that the young radio supernova SN 1993J is expanding with circular
symmetry. However, the circularly symmetric images show emission
asymmetries. A scenario in which freely expanding supernova ejecta
shock mostly isotropic circumstellar material is strongly favored. The
sequence of images constitutes the first ``movie'' of
a radio
supernova.
J. M. Marcaide and E. Ros, Departamento de Astronomía,
Universitat de València, E-46100 Burjassot, València,
Spain.
A. Alberdi, Laboratorio de Astrofísica Espacial y
Física Fundamental, Instituto Nacional de Técnica
Aeroespacial (INTA), E-28080 Madrid, Spain, and Instituto de
Astrofísica de Andalucía-Consejo Superior de
Investigaciones Cientificas (CSIC), Apdo. Correos 3004, E-18080
Granada, Spain.
P. Diamond, National Radio Astronomy Observatory, Socorro, NM 87801,
USA.
I. I. Shapiro, Harvard-Smithsonian Center for Astrophysics, Cambridge,
MA 02138, USA.
J. C. Guirado, D. L. Jones, R. A. Preston, Jet Propulsion Laboratory,
California Institute of Technology, Pasadena, CA 91109, USA.
T. P. Krichbaum and A. Witzel, Max-Planck Institut für
Radioastronomie, Auf dem Hügel 69, D-50131 Bonn, Germany.
F. Mantovani, Istituto di Radioastronomia, Consiglio Nazionale delle
Ricerche (CNR), I-Bologna 40129, Italy.
A. Rius, Laboratorio de Astrofísica Espacial y Física
Fundamental, INTA, E-28080 Madrid, Spain, and Centre d'Estudis
Avançats-C.S.I.C., Camí de Santa Barbara s/n, E-17300
Blanes, Girona, Spain.
R. T. Schilizzi, Joint Institute for VLBI in Europe, Postbus 2, 7990 AA
Dwingeloo, Netherlands, and Leiden Observatory, Postbus 9513, 2300 RA
Leiden, Netherlands.
C. Trigilio, Istituto di Radioastronomia, CNR, Noto, Italy.
A. R. Whitney, Massachusetts Institute of Technology-Haystack
Observatory, Westford, MA 01886, USA.
(1) To whom correspondence should be addressed.
