English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Based on high-resolution ultraviolet spectroscopy obtained with FUSE and COS,we present new detections of O VI and N V emission from the black-hole X-raybinary (XRB) system LMC X-3. We also update the ephemeris of the XRB usingrecent radial velocity measurements obtained with the echelle spectrograph onthe Magellan-Clay telescope. We observe significant velocity variability of theUV emission, and we find that the O VI and N V emission velocities follow theoptical velocity curve of the XRB. Moreover, the O VI and N V intensitiesregularly decrease between binary phase = 0.5 and 1.0, which suggests that thesource of the UV emission is increasingly occulted as the B star in the XRBmoves from superior to inferior conjunction. These trends suggest thatillumination of the B-star atmosphere by the intense X-ray emission from theaccreting black hole creates a hot spot on one side of the B star, and this hotspot is the origin of the O VI and N V emission. However, the velocitysemiamplitude of the ultraviolet emission, K_{UV}~180 km/s, is lower than theoptical semiamplitude; this difference could be due to rotation of the B star.If our hypothesis about the origin of the highly ionized emission is correct,then careful analysis of the emission occultation could, in principle,constrain the inclination of the XRB and the mass of the black hole.

Variable O VI and N V Emission from the X-ray Binary LMC X-3: Heating of the Black Hole Companion