2024MNRAS.535.2812S -
Mon. Not. R. Astron. Soc., 535, 2812-2836 (2024/December-2)
HD 34736: an intensely magnetised double-lined spectroscopic binary with rapidly rotating chemically peculiar B-type components.
SEMENKO E., KOCHUKHOV O., MIKULASEK Z., WADE G.A., ALECIAN E., BOHLENDER D., DAS B., FELIZ D.L., JANIK J., KOLAR J., KRTICKA J., KUDRYAVTSEV D.O., LABADIE-BARTZ J.M., MKRTICHIAN D., MONIN D., PETIT V., ROMANYUK I.I., SHULTZ M.E., SHULYAK D., SIVERD R.J., TKACHENKO A., YAKUNIN I.A., ZEJDA M. (The BinaMIcS Collaboration)
Abstract (from CDS):
We report the results of a comprehensive study of the spectroscopic binary (SB2) system HD 34736 hosting two chemically peculiar (CP) late B-type stars. Using new and archival observational data, we characterize the system and its components, including their rotation and magnetic fields. Fitting of the radial velocities yields $P_\mathrm{orb}=83\rm{.\!\!^{ {\rm{d}}}}219(3)$ and $e=0.8103(3)$. The primary component is a CP He-wk star with $T_{{\rm eff}A}$$\,\,=13000\pm 500$ K and $\upsilon _{\rm e}\sin i\,$$\,\,=75\pm 3$ km s$^{-1}\,$, while the secondary exhibits variability of Mg and Si lines, and has $T_{{\rm eff}B}$$\,\,=11500\pm 1000$ K and $\upsilon _{\rm e}\sin i\,$$\,\,=110$-180 km s$^{-1}\,$. Transiting Exoplanet Survey Satellite and Kilodegree Extremely Little Telescope photometry reveal clear variability of the primary component with a rotational period $P_{\mathrm{rot}A}=1\rm{.\!\!^{ {\rm{d}}}}279\, 988\, 5(11)$, which is lengthening at a rate of 1.26(6) s yr$^{-1}$. For the secondary, $P_{\mathrm{rot}B}=0\rm{.\!\!^{ {\rm{d}}}}522\, 693\, 8(5)$, reducing at a rate of $-0.14(3)$ s yr$^{-1}$. The longitudinal component $\langle B_{\rm z}\rangle$ of the primary's strongly asymmetric global magnetic field varies from $-6$ to +5 kG. Weak spectropolarimetric evidence of a magnetic field is found for the secondary star. The observed X-ray and radio emission of HD 34736 may equally be linked to a suspected T Tau-like companion or magnetospheric emission from the principal components. Given the presence of a possible third magnetically active body, one can propose that the magnetic characteristics of the protostellar environment may be connected to the formation of such systems.
Abstract Copyright:
© 2024 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society.
Journal keyword(s):
techniques: polarimetric - binaries: spectroscopic - stars: chemically peculiar - stars: magnetic fields
Status at CDS
:
Large table(s) will be appraised for possible ingestion in VizieR.
Simbad objects:
14
Full paper
View the references in ADS
To bookmark this query, right click on this link: simbad:2024MNRAS.535.2812S and select 'bookmark this link' or equivalent in the popup menu