Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Simulating X-ray bursts during a transient accretion event   Modelling of thermonuclear X-ray bursts on accreting neutron stars has to
date focused on stable accretion rates. However, bursts are also observed
during episodes of transient accretion. During such events, the accretion rate
can evolve significantly between bursts, and this regime provides a unique test
for burst models. The accretion-powered millisecond pulsar SAX J1808.4-3658
exhibits accretion outbursts every 2-3 years. During the well-sampled
month-long outburst of 2002 October, four helium-rich X-ray bursts were
observed. Using this event as a test case, we present the first multi-zone
simulations of X-ray bursts under a time-dependent accretion rate. We
investigate the effect of using a time-dependent accretion rate in comparison
to constant, averaged rates. Initial results suggest that using a constant,
average accretion rate between bursts may underestimate the recurrence time
when the accretion rate is decreasing, and overestimate it when the accretion
rate is increasing. Our model, with an accreted hydrogen fraction of $X=0.44$
and a CNO metallicity of $Z_\mathrm{CNO}=0.02$, reproduces the observed burst
arrival times and fluences with root mean square (RMS) errors of
$2.8\,\mathrm{h}$, and $0.11\times 10^{-6}\,\mathrm{erg\, cm^{-2}}$,
respectively. Our results support previous modelling that predicted two
unobserved bursts, and indicate that additional bursts were also missed by
observations.

24
The categories of this paper are: dg-ga
30
The categories of this paper are: q-alg
15
The categories of this paper are: nucl-ex
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph
4
The categories of this paper are: cond-mat
14
The categories of this paper are: math-ph
18
The categories of this paper are: econ
31
The categories of this paper are: ao-sci
3
The categories of this paper are: physics
16
The categories of this paper are: stat
10
The categories of this paper are: q-bio
35
The categories of this paper are: mtrl-th
1
The categories of this paper are: cs
28
The categories of this paper are: alg-geom
0
The categories of this paper are: hep-ph