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A transient radio jet in an erupting dwarf nova

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 نشر من قبل Elmar K\\\"ording
 تاريخ النشر 2008
  مجال البحث فيزياء
والبحث باللغة English
 تأليف Elmar Koerding




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Astrophysical jets seem to occur in nearly all types of accreting objects: from supermassive black holes to young stellar objects. Based on X-ray binaries, a unified scenario describing the disc/jet coupling has evolved and extended to many accreting objects. The only major exceptions are thought to be cataclysmic variables: Dwarf novae, weakly accreting white dwarfs, show similar outburst behaviour as X-ray binaries but no jet has yet been detected. Here we present radio observations of a dwarf nova in outburst showing variable flat-spectrum radio emission that is best explained as synchrotron emission originating in a transient jet. Both the inferred jet power and the relation to the outburst cycle are analogous to those seen in X-ray binaries, suggesting that the disc/jet coupling mechanism is ubiquitous.

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