J/MNRAS/473/2275 low-ionization structures around NGC 1360 (Miszalski+, 2018)
SALT HRS discovery of a long-period double-degenerate binary in the planetary
nebula NGC 1360.
Miszalski B., Manick R., Mikolajewska J., Ilkiewicz K., Kamath D.,
Van Winckel H.
<Mon. Not. R. Astron. Soc., 473, 2275-2287 (2018)>
=2018MNRAS.473.2275M 2018MNRAS.473.2275M (SIMBAD/NED BibCode)
ADC_Keywords: Planetary nebulae ; Positional data
Keywords: techniques: radial velocities - stars: AGB and post-AGB -
binaries: spectroscopic - white dwarfs - planetary nebulae: general -
planetary nebulae: individual: NGC 1360
Abstract:
Whether planetary nebulae (PNe) are predominantly the product of
binary stellar evolution as some population synthesis models (PSM)
suggest remains an open question. Around 50 short-period binary
central stars (P∼1d) are known, but with only four with measured
orbital periods over 10 d, our knowledge is severely incomplete.
Here we report on the first discovery from a systematic Southern
African Large Telescope (SALT) High Resolution Spectrograph (HRS)
survey for long-period binary central stars. We find a 142d orbital
period from radial velocities of the central star of NGC 1360,
HIP 16566. NGC 1360 appears to be the product of common-envelope
(CE) evolution, with nebula features similar to post-CE PNe, albeit
with an orbital period considerably longer than expected to be typical
of post-CE PSM. The most striking feature is a newly identified ring
of candidate low-ionization structures. Previous spatiokinematic
modelling of the nebula gives a nebula inclination of
30°±10°, and assuming the binary nucleus is coplanar with
the nebula, multiwavelength observations best fit a more massive,
evolved white dwarf (WD) companion. A WD companion in a 142d orbit is
not the focus of many PSM, making NGC 1360 a valuable system with
which to improve future PSM work. HIP 16566 is amongst many central
stars in which large radial velocity variability was found by
low-resolution surveys. The discovery of its binary nature may
indicate long-period binaries may be more common than PSM models
predict.
Description:
We used the High Resolution Spectrograph to observe HIP 16566.
We searched for candidate LIS by blinking together the
Hα+[NII], I band and quotient (Hα+[NII]/I-band) images
with the ds9 program.
Table A1 lists the coordinates of the 120 LIS candidates identified.
Objects:
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RA (2000) DE Designation(s)
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03 33 14.65 -25 52 18.0 HIP 16566 = NGC 1360
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 20 120 Coordinates of the low-ionization structures
(LIS) candidates
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 9 F9.6 deg RAdeg Right ascension (J2000)
11- 20 F10.6 deg DEdeg Declination (J2000)
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 21-Nov-2020