The puzzling orbital period evolution of the low mass X-ray binary AX J1745.6-2901

Abstract

The orbital period evolution of X-ray binaries provides fundamental clues to understanding mechanisms of angular momentum loss from these systems. We present an X-ray eclipse timing analysis of the transient low mass X-ray binary AX J1745.6-2901. This system shows full eclipses and thus is one of the few objects for which accurate orbital evolution studies using this method can be carried out. We report on XMM-Newton and ASCA observations covering 30 complete X-ray eclipses spanning an interval of more than 20 years. We improve the determination of the orbital period to a relative precision of $2\times 10^{-8}$, two orders of magnitudes better than previous estimates. We determine, for the first time, a highly significant rate of decrease of the orbital period ${\dot{P}}_{orb}=-4.03\pm 0.32\times 10^{-11}$~s/s. This is at least one order of magnitude larger than expected from conservative mass transfer and angular momentum losses due to gravitational waves and magnetic breaking, and might result from non-conservative mass transfer. Imprinted on the long term evolution of the orbit, we observe highly significant eclipse leads-delays of ~10-20 s, characterised by a clear state dependence in which, on average, eclipses occur earlier during the hard state.

Submitted to MNRAS

References in corpus (14)

• Modelling the behaviour of accretion flows in X-ray binaries
• Black hole-like hysteresis and accretion states in neutron star low mass X-ray binaries
• Regulation of black-hole accretion by a disk wind during a violent outburst of V404 Cygni
• Orbital Evolution of an Accreting Millisecond Pulsar: Witnessing the Banquet of a Hidden Black Widow?
• A decade of timing an accretion-powered millisecond pulsar: The continuing spin down and orbital evolution of SAX J1808.4-3658
• Analysing the atolls: X-ray spectral transitions of accreting neutron stars
• A connection between accretion state and $\text{Fe K absorption}$ in an accreting neutron star: black hole-like soft state winds?
• New ephemeris of the ADC source 2A 1822-371: a stable orbital-period derivative over 30 years
• Eclipse Timings of the Transient Low Mass X-ray Binary EXO0748-676. IV. The Rossi X-Ray Timing Explorer Eclipses
• On the Fe K absorption - accretion state connection in the Galactic center neutron star X-ray binary AX J1745.6-2901
• High ionisation absorption in low mass X-ray binaries
• Parameterization studies of the properties of the X-ray dips for Low Mass X-ray binary X1916-053
• Measuring the orbital periods of low mass X-ray binaries in the X-ray band
• Possible Magnetic Activity in the Low Mass X-ray Binary EXO 0748-676

Cited by in corpus (20)

• Low-Mass X-ray Binaries
• Radio pulse search and X-Ray monitoring of SAX J1808.4-3658: What Causes its Orbital Evolution?
• Probing the Interstellar Dust towards the Galactic Centre: Dust Scattering Halo around AX J1745.6-2901
• The X-ray binary population in the Galactic Center revealed through multi-decade observations
• Photoionization instability of the Fe K absorbing plasma in the neutron star transient AX J1745.6-2901
• A possible solution of the puzzling variation of the orbital period of MXB 1659-298
• NuSTAR + XMM-Newton monitoring of the neutron star transient AX J1745.6-2901
• The Galactic LMXB Population and the Galactic Centre Region
• Indication of a massive circumbinary planet orbiting the Low Mass X-ray Binary MXB 1658-298
• Searching for Exoplanets Around X-Ray Binaries with Accreting White Dwarfs, Neutron Stars, and Black Holes
• A Circumbinary Disk Model for the Rapid Orbital Shrinkage in Black Hole Low-Mass X-ray Binaries
• Neutron Stars in X-ray Binaries and their Environments
• Eclipse Timings of the LMXB XTE J1710-281 : Discovery of a third orbital period glitch
• A Spectroscopic Angle on Central Engine Size Scales in Accreting Neutron Stars
• Evolution of the disc atmosphere in the X-ray binary MXB 1659-298, during its 2015-2017 outburst
• Accretion disc winds in X-ray binaries
• Population synthesis of AX J1745.6-2901 X-ray nova type binaries with rapidly decreasing orbital periods
• The puzzling orbital residuals of XTE J1710-281: is a Jovian planet orbiting around the binary system?
• Impact on orbital period of X-ray Binary system attached to a cosmic string
• Updated Orbital Ephemeris and Detection of Superhump Modulation in X-ray Band for the Ultra-Compact Low Mass X-ray Binary 4U 1820-30