Binary orbits as the driver of gamma-ray emission and mass ejection in classical novae
Artikel i vetenskaplig tidskrift, 2014

Classical novae are the most common astrophysical thermonuclear explosions, occurring on the surfaces of white dwarf stars accreting gas from companions in binary star systems(1). Novae typically expel about 10(-4) solar masses of material at velocities exceeding 1,000 kilometres per second. However, the mechanism of mass ejection in novae is poorly understood, and could be dominated by the impulsive flash of thermonuclear energy(2), prolonged optically thick winds(3) or binary interaction with the nova envelope(4). Classical novae are now routinely detected at gigaelectronvolt gamma-ray wavelengths(5), suggesting that relativistic particles are accelerated by strong shocks in the ejecta. Here we report high-resolution radio imaging of the gamma-ray-emitting nova V959 Mon. We find that its ejecta were shaped by the motion of the binary system: some gas was expelled rapidly along the poles as a wind from the white dwarf, while denser material drifted out along the equatorial plane, propelled by orbital motion(6,7). At the interface between the equatorial and polar regions, we observe synchrotron emission indicative of shocks and relativistic particle acceleration, thereby pinpointing the location of gamma-ray production. Binary shaping of the nova ejecta and associated internal shocks are expected to be widespread among novae(8), explaining why many novae are gamma-ray emitters(5).


L. Chomiuk

Michigan State University

Justin D. Linford

Michigan State University

Jun Yang

Chalmers, Rymd- och geovetenskap, Onsala rymdobservatorium

T. J. O'Brien

University of Manchester

Z. Paragi

Joint Institute for VLBI in Europe

A. J. Mioduszewski

National Radio Astronomy Observatory

R. J. Beswick

University of Manchester

C. C. Cheung

Naval Research Laboratory

K. Mukai

University of Maryland, Baltimore County

NASA Goddard Space Flight Center

T. Nelson

University of Minnesota System

Varm Ribeiro

University of Cape Town

M. P. Rupen

National Radio Astronomy Observatory

National Research Council Canada

J. L. Sokoloski

Columbia University in the City of New York

J. Weston

Columbia University in the City of New York

Y. Zheng

Columbia University in the City of New York

M. F. Bode

Liverpool John Moores University

S. Eyres

University of Central Lancashire

N. Roy

Max Planck-institutet

G. Taylor

University of New Mexico


0028-0836 (ISSN) 1476-4687 (eISSN)

Vol. 514 339-+


Astronomi, astrofysik och kosmologi