Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: iPTF16asu: A Luminous, Rapidly-Evolving, and High-Velocity Supernova   Wide-field surveys are discovering a growing number of rare transients whose
physical origin is not yet well understood. Here, we present optical and UV
data and analysis of iPTF16asu, a luminous, rapidly-evolving, high velocity,
stripped-envelope supernova. With a rest-frame rise-time of just 4 days and a
peak absolute magnitude of $M_{\rm g}=-20.4$ mag, the light curve of iPTF16asu
is faster and more luminous than previous rapid transients. The spectra of
iPTF16asu show a featureless, blue continuum near peak that develops into a
Type Ic-BL spectrum on the decline. We show that while the late-time light
curve could plausibly be powered by $^{56}$Ni decay, the early emission
requires a different energy source. Non-detections in the X-ray and radio
strongly constrain any associated gamma-ray burst to be low-luminosity. We
suggest that the early emission may have been powered by either a rapidly
spinning-down magnetar, or by shock breakout in an extended envelope of a very
energetic explosion. In either scenario a central engine is required, making
iPTF16asu an intriguing transition object between superluminous supernovae,
Type Ic-BL supernovae, and low-energy gamma-ray bursts.

26
The categories of this paper are: bayes-an
31
The categories of this paper are: ao-sci
15
The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
14
The categories of this paper are: math-ph
2
The categories of this paper are: math
10
The categories of this paper are: q-bio
8
The categories of this paper are: hep-ex
13
The categories of this paper are: quant-ph
28
The categories of this paper are: alg-geom
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The categories of this paper are: patt-sol
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The categories of this paper are: comp-gas
0
The categories of this paper are: hep-ph
3
The categories of this paper are: physics
30
The categories of this paper are: q-alg
9
The categories of this paper are: nlin