# A Hard Look at the Neutron Stars and Accretion Disks in 4U 1636-53, GX 17+2, and 4U 1705-44 with NuStar

@article{Ludlam2017AHL,
title={A Hard Look at the Neutron Stars and Accretion Disks in 4U 1636-53, GX 17+2, and 4U 1705-44 with NuStar},
author={Renee M. Ludlam and Jonathan M. Miller and Matteo Bachetti and Didier Barret and Allison Bostrom and Edward M. Cackett and Nathalie Degenaar and Tiziana di Salvo and Lorenzo Natalucci and John A. Tomsick and Frits B. S. Paerels and Michael L. Parker},
journal={The Astrophysical Journal},
year={2017},
volume={836},
pages={140}
}
We present NuSTAR observations of neutron star (NS) low-mass X-ray binaries: 4U 1636-53, GX 17+2, and 4U 1705-44. We observed 4U 1636-53 in the hard state, with an Eddington fraction, {F}{Edd}, of 0.01; GX 17+2 and 4U 1705-44 were in the soft state with fractions of 0.57 and 0.10, respectively. Each spectrum shows evidence for a relativistically broadened Fe K α line. Through accretion disk reflection modeling, we constrain the radius of the inner disk in 4U 1636-53 to be {R}{in}=1.03+/- 0.03… Expand

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