SIMBAD references

2010A&A...509A..79M - Astronomy and Astrophysics, volume 509, A79-79 (2010/1-1)

Preliminary determinations of the masses of the neutron star and mass donor in the high mass X-ray binary system EXO 1722-363.


Abstract (from CDS):

We intended to measure the radial velocity curve of the supergiant companion to the eclipsing high mass X-ray binary pulsar EXO 1722-363 and hence determine the stellar masses of the components. We used a set of archival Ks-band infrared spectra of the counterpart to EXO 1722-363 obtained using ISAAC on the VLT, and cross-correlated them in order to measure the radial velocity of the star. The resulting radial velocity curve has a semi-amplitude of 24.5 ±5.0km/s. When combined with other measured parameters of the system, this yields masses in the range 1.5±0.4-1.6±0.4M for the neutron star and 13.6±1.6-15.2±1.9M for the B0-1 Ia supergiant companion. These lower and upper limits were obtained under the assumption that the system is viewed edge-on (i=90°) for the lower limit and the supergiant fills its Roche lobe (β=1) for the upper limit respectively. The system inclination is constrained to i>75° and the Roche lobe-filling factor of the supergiant is β>0.9. Additionally we were able to further constrain our distance determination to be 7.1≤d≤7.9kpc for EXO 1722-363. The X-ray luminosity for this distance range is 4.7x1035≤LX≤9.2x1036erg/s. EXO 1722-363 therefore becomes the seventh of the ten known eclipsing X-ray binary pulsars for which a dynamical neutron star mass solution has been determined. Additionally EXO 1722-363 is the first such system to have a neutron star mass measurement made utilising near-infrared spectroscopy.

Abstract Copyright:

Journal keyword(s): pulsars: general - binaries: eclipsing - binaries: general - X-rays: binaries - stars: individual: EXO 1722-363 - stars: neutron

Simbad objects: 12

goto Full paper

goto View the reference in ADS

To bookmark this query, right click on this link: simbad:2010A&A...509A..79M and select 'bookmark this link' or equivalent in the popup menu


© Université de Strasbourg/CNRS

    • Contact