Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: XMM-Newton Campaign On Ultraluminous X-ray Source NGC 1313 X-1: Wind vs.
  State Variability   Most ultraluminous X-ray sources (ULXs) are thought to be powered by neutron
stars and black holes accreting beyond the Eddington limit. If the compact
object is a black hole or a neutron star with a magnetic field
$\lesssim10^{12}$ G, the accretion disc is expected to thicken and launch
powerful winds driven by radiation pressure. Evidence of such winds has been
found in ULXs through the high-resolution spectrometers onboard XMM-Newton, but
several unknowns remain, such as the geometry and launching mechanism of these
winds. In order to better understand ULX winds and their link to the accretion
regime, we have undertaken a major campaign with XMM-Newton to study the ULX
NGC 1313 X-1, which is known to exhibit strong emission and absorption features
from a mildly-relativistic wind. The new observations show clear changes in the
wind with a significantly weakened fast component (0.2c) and the rise of a new
wind phase which is cooler and slower (0.06-0.08c). We also detect for the
first time variability in the emission lines which indicates an origin within
the accretion disc or in the wind. We describe the variability of the wind in
the framework of variable super-Eddington accretion rate and discuss a possible
geometry for the accretion disc.

24
The categories of this paper are: dg-ga
11
The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
10
The categories of this paper are: q-bio
21
The categories of this paper are: adap-org
27
The categories of this paper are: comp-gas
20
The categories of this paper are: acc-phys
19
The categories of this paper are: eess
8
The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom
26
The categories of this paper are: bayes-an
15
The categories of this paper are: nucl-ex
1
The categories of this paper are: cs
30
The categories of this paper are: q-alg
12
The categories of this paper are: nucl-th
22
The categories of this paper are: chao-dyn