J/A+A/607/A60 BD+46 442 optical spectra (Bollen+, 2017)
Jet creation in post-AGB binaries: the circum-companion accretion disc around
BD+46 442.
Bollen D., Van Winckel H., Kamath D.
<Astron. Astrophys. 607, A60 (2017)>
=2017A&A...607A..60B 2017A&A...607A..60B (SIMBAD/NED BibCode)
ADC_Keywords: Binaries, spectroscopic ; Line Profiles ; Spectroscopy
Keywords: stars: individual: BD+46 442 - stars: AGB and post-AGB -
stars: binaries: spectroscopic - ISM: jets and outflows -
circumstellar matter - accretion, accretion disks
Abstract:
We aim at describing and understanding binary interaction processes in
systems with very evolved companions. Here, we focus on understanding
the origin and determining the properties of the high-velocity outflow
observed in one such system.
We present a quantitative analysis of BD+46 442, a post-AGB binary
which shows active mass transfer that leads to the creation of a
disk-driven outflow or jet. We obtained high-resolution optical
spectra from the HERMES spectrograph, mounted on the 1.2m Flemish
Mercator Telescope. By performing a time-series analysis of the
Hα profile, we dissected the different components of the system.
We deduced the jet geometry by comparing the orbital phased data with
our jet model. In order to image the accretion disk around the
companion of BD+46 442, we applied the technique of Doppler
tomography. Results: The orbital phase-dependent variations in the
Hα profile can be related to an accretion disk around the
companion, from which a high-velocity outflow or jet is launched. Our
model shows that there is a clear correlation between the inclination
angle and the jet opening angle. The latitudinally dependent velocity
structure of our jet model shows a good correspondence to the data,
with outflow velocities at least higher than 400km/s. The intensity
peak in the Doppler map might be partly caused by a hot spot in the
disk, or a larger asymmetrical structure in the disk.
We show that BD+46 442, is a result of a binary interaction channel.
The origin of the fast outflow in this system can be attributed to a
gaseous disk around the secondary component, which is most likely a
main sequence star. Our analysis suggests the outflow to have a rather
wide opening angle instead of being strongly collimated. Our time
resolved spectral monitoring reveals the launching site of the jet in
the binary BD+46 442. Similar orbital phase-dependent Hα
profiles are commonly observed in post-AGB binaries. Post-AGB binaries
provide ideal test bets to study jet formation and launching
mechanisms over a wide range of orbital conditions.
Description:
Reduced high-resolution (R∼85000) optical spectra of BD+46 442.
These 104 spectra were obtained between July 2009 and January 2016
from the HERMES spectrograph, mounted on the 1.2m Flemish Mercator
telescope at La Palma, Canary Islands, Spain. The spectra cover a
wavelength range from 3770 to 9000 angstrom in logscale. The flux is
given in arbitrary units. The spectra are collected as FITS files. The
numbering of the spectra corresponds to the numbering in Table B.1 in
the article (e.g. spec_15.fits corresponds to N=15).
Objects:
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RA (2000) DE Designation(s)
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01 45 47.03 +46 49 01.0 BD+46 442 = IRAS 01427+4633
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 106 104 List of fits spectra
fits/* . 104 Individual spectra
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 6 I6 --- Nx Number of pixels along X-axis
8- 33 A26 --- Obs.date Observation date (YYYY-MM-DDThh:mm:ss.ssssss)
35- 41 F7.5 [0.1nm] logWmin Lower value of wavelength interval
43- 49 F7.5 [0.1nm] logWmax Upper value of wavelength interval
51- 61 E11.6 0.1nm dW Wavelength resolution
63- 66 I4 Kibyte size Size of FITS file
68- 79 A12 --- FileName Name of FITS file, in subdirectory fits
81-106 A26 --- Title Title of the FITS file
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Acknowledgements:
Dylan Bollen, dylan.bollendb(at)gmail.com
(End) Dylan Bollen [KU Leuven], Patricia Vannier [CDS] 03-Aug-2017