Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Are Delayed Radio Flares Common in Tidal Disruption Events? The Case of
  the TDE iPTF16fnl   Radio emission from tidal disruption events (TDEs) originates from an
interaction of an outflow with the super-massive black hole (SMBH) circum
nuclear material (CNM). In turn, this radio emission can be used to probe
properties of both the outflow launched at the event and the CNM. Until
recently, radio emission was detected only for a relatively small number of
events. While the observed radio emission pointed to either relativistic or
sub-relativistic outflows of different nature, it also indicated that the
outflow has been launched shortly after the stellar disruption. Recently,
however, delayed radio flares, several months and years after stellar
disruption, were reported in the case of the TDE ASASSN-15oi. These delayed
flares suggest a delay in the launching of outflows and thus may provide new
insights into SMBH accretion physics. Here, we present a new radio dataset of
another TDE, iPTF16fnl, and discuss the possibility that a delayed radio flare
has been observed also in this case, ~ 5 months after optical discovery,
suggesting that this phenomenon may be common in TDEs. Unlike ASASSN-15oi, the
data for iPTF16fnl is sparse and the delayed radio flare can be explained by
several alternative models: among them are a complex varying CNM density
structure and a delayed outflow ejection.

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The categories of this paper are: mtrl-th
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The categories of this paper are: q-fin
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The categories of this paper are: nucl-th
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The categories of this paper are: nlin
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The categories of this paper are: eess
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The categories of this paper are: quant-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: cond-mat
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The categories of this paper are: physics
5
The categories of this paper are: gr-qc
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The categories of this paper are: hep-ex
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The categories of this paper are: stat
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The categories of this paper are: dg-ga
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The categories of this paper are: hep-lat
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The categories of this paper are: q-bio
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The categories of this paper are: math-ph