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

Analyses of multi-epoch, high-resolution (R ~ 50.000) optical spectra of theO-type star HD 152246 (O9 IV according to the most recent classification),complemented by a limited number of earlier published radial velocities, led tothe finding that the object is a hierarchical triple system, where a closeinner pair (Ba-Bb) with a slightly eccentric orbit (e = 0.11) and a period of6.0049 days revolves in a 470-day highly eccentric orbit (e = 0.865) withanother massive and brighter component A. The mass ratio of the inner systemmust be low since we were unable to find any traces of the secondary spectrum.The mass ratio A/(Ba+Bb) is 0.89. The outer system has recently been resolvedusing long-baseline interferometry on three occasions. The interferometryconfirms the spectroscopic results and specifies elements of the system. Ourorbital solutions, including the combined radial-velocity and interferometricsolution indicate an orbital inclination of the outer orbit of 112{\deg} andstellar masses of 20.4 and 22.8 solar masses. We also disentangled the spectraof components A and Ba and compare them to synthetic spectra from twoindependent programmes, TLUSTY and FASTWIND. In either case, the fit was notsatisfactory and we postpone a better determination of the system propertiesfor a future study, after obtaining observations during the periastron passageof the outer orbit (the nearest chance being March 2015). For the moment, wecan only conclude that component A is an O9 IV star with v*sin(i) = 210 +\- 10km/s and effective temperature of 33000 +\- 500 K, while component Ba is an O9V object with v*sin(i) = 65 +/- 3 km/s and T_eff = 33600 +\- 600 K.

HD 152246 - a new high-mass triple system and its basic properties