Fast orbital shrinkage of black hole X-ray binaries driven by circumbinary disks. (arXiv:1904.09753v1 [astro-ph.HE])
<a href="http://arxiv.org/find/astro-ph/1/au:+Chen_W/0/1/0/all/0/1">Wen-Cong Chen</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Podsiadlowski_P/0/1/0/all/0/1">Philipp Podsiadlowski</a>
Recently, the black hole X-ray binary (BHXB) Nova Muscae 1991 has been
reported to be experiencing an extremely rapid orbital decay. So far, three
BHXBs have anomalously high orbital period derivatives, which can not be
interpreted by the standard stellar evolution theory. In this work, we
investigate whether the resonant interaction between the binary and a
surrounding circumbinary (CB) disk could produce the observed orbital period
derivatives. Analytical calculations indicate that the observed orbital period
derivatives of XTE J1118+480 and A0620-00 can originate from the tidal torque
between the binary and a CB disk with a mass of $10^{-9}~rm M_{odot}$, which
is approximately in agreement with the dust disk mass detected in these two
sources. However, Nova Muscae 1991 was probably surrounded by a heavy CB disk
with a mass of $10^{-7}~rm M_{odot}$. Based on the CB disk model and the
anomalous magnetic braking theory, we simulate the evolution of the three BHXBs
with intermediate-mass donor stars by using the MESA code. Our simulated
results are approximately consistent with the observed donor star masses,
orbital periods, and orbital-period derivatives. However, the calculated
effective temperatures of the donor stars are higher than indicated by the
observed spectral types of two sources.
Recently, the black hole X-ray binary (BHXB) Nova Muscae 1991 has been
reported to be experiencing an extremely rapid orbital decay. So far, three
BHXBs have anomalously high orbital period derivatives, which can not be
interpreted by the standard stellar evolution theory. In this work, we
investigate whether the resonant interaction between the binary and a
surrounding circumbinary (CB) disk could produce the observed orbital period
derivatives. Analytical calculations indicate that the observed orbital period
derivatives of XTE J1118+480 and A0620-00 can originate from the tidal torque
between the binary and a CB disk with a mass of $10^{-9}~rm M_{odot}$, which
is approximately in agreement with the dust disk mass detected in these two
sources. However, Nova Muscae 1991 was probably surrounded by a heavy CB disk
with a mass of $10^{-7}~rm M_{odot}$. Based on the CB disk model and the
anomalous magnetic braking theory, we simulate the evolution of the three BHXBs
with intermediate-mass donor stars by using the MESA code. Our simulated
results are approximately consistent with the observed donor star masses,
orbital periods, and orbital-period derivatives. However, the calculated
effective temperatures of the donor stars are higher than indicated by the
observed spectral types of two sources.
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