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

RX J0513.1+0851 and RX J0539.9+0956 were previously identified as young,low-mass, single-lined spectroscopic binary systems and classified asweak-lined T Tauri stars at visible wavelengths. Here we present radialvelocities, spectral types, vsini values, and flux ratios for the components inthese systems resulting from two-dimensional cross-correlation analysis. Theseresults are based on high-resolution, near-infrared spectroscopy taken with theKeck II telescope to provide a first characterization of these systems asdouble-lined rather than single-lined. It applies the power of infraredspectroscopy to the detection of cool secondaries; the flux scales as a lesssteep function of mass in the infrared than in the visible, thus enabling anidentification of low-mass secondaries. We found that the RX J0513.1+0851 andRX J0539.9+0956 primary stars are fast rotators, 60 km/s and 80 km/srespectively; this introduces extra difficulty in the detection of thesecondary component as a result of the quite broad absorption lines. To date,these are the highest rotational velocities measured for a pre-main sequencespectroscopic binary. The orbital parameters and mass ratios were determined bycombining new visible light spectroscopy with our infrared data for bothsystems. For RX J0513.1+0851, we derived a period of ~4 days and a mass ratioof q = 0.46 +/- 0.01 and for RX J0539.9+0956, a period of ~1117 days and a massratio of q = 0.66 +/- 0.01. Based on our derived properties for the stellarcomponents, we estimate the luminosities and hence distances to these binariesat 220 pc and 90 pc. They appear to be significantly closer than previouslyestimated.

RX J0513.1+0851 AND RX J0539.9+0956: Two Young, Rapidly Rotating, Spectroscopic Binary Stars