J/A+A/567/A15 Hen 2-260 emission line fluxes (Hajduk+, 2014)
The evolving spectrum of the planetary nebula Hen 2-260.
Hajduk M., van Hoof P.A.M., Gesicki K., Zijlstra A.A., Gorny S.,
Gladkowski M.
<Astron. Astrophys. 567, A15 (2014)>
=2014A&A...567A..15H 2014A&A...567A..15H
ADC_Keywords: Planetary nebulae ; Interstellar medium ; Spectroscopy
Keywords: stars: AGB and post-AGB - stars: evolution -
planetary nebulae: general - planetary nebulae: individual: Hen 2-260
Abstract:
We analysed the planetary nebula Hen 2-260 using optical spectroscopy
and photometry. We compared our observations with the literature data
in order to search for evolutionary changes. We also searched for
photometric variability of the central star. Hen 2-260 was observed
with the SAAO 1.0m telescope (photometry) and the SALT telescope (low
resolution spectroscopy). We also used archive high resolution Very
Large Telescope spectra and Hubble Space Telescope imaging. The
nebular line fluxes were modelled with the Cloudy photoionization code
in order to derive the stellar and nebular parameters. The planetary
nebula shows a complex structure and possibly a bipolar outflow. The
nebula is relatively dense and young. The central star is just
starting O+ ionization (Teff∼30000K). Comparison of our observations
with literature data indicates a 50% increase of the [OIII] 5007Å
line flux between 2001 and 2012. We interpret it as the result of the
progression of the ionization of O+. The central star evolves to
higher temperatures at a rate of 45±7K/yr. The heating rate is
consistent with post-AGB evolutionary tracks for a final mass of
0.626+0.003-0.005M☉ or 0.645±0.008M☉ for two
different sets of tracks from literature. The photometric monitoring
of Hen 2-260 revealed non-periodic variations on a timescale of hours
or days. There is no direct indication for central star binarity in
the spectrum, nor for a strong stellar wind. The variability may be
caused by pulsations of the star. The temperature evolution of the
central star can be traced using spectroscopic observations of the
surrounding planetary nebula spanning a timescale of roughly a decade.
This allows us for precise determination of the stellar mass, since
the pace of the temperature evolution depends critically on the core
mass. The method is independent on the absolute age of the nebula. The
kinematical age of the nebula is consistent with the age obtained from
the evolutionary track. The final mass of the central star is close to
the peak of the mass distribution for central stars of planetary
nebulae found in other studies. The object belongs to a group of young
central stars of planetary nebulae showing photometric variability.
Description:
Identifications and fluxes of the emission lines in the VLT spectrum
of Hen 2-260.
Objects:
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RA (2000) DE Designation(s)
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17 38 57.1 -18 17 35 Hen 2-260 = PN G008.2+06.8
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 70 104 Emission line fluxes in the VLT spectrum of Hen 2-260
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 8 F8.3 0.1nm lam.obs [3660/6584] Observed wavelength λobs
10- 17 F8.3 0.1nm lam.lab [3660/6584] Laboratory wavelength λlab
19- 25 A7 --- Ion Ion
27- 55 A29 --- Term Transition term
57- 63 F7.1 10-19W/m2 F Observed Flux F(λ) (10-16erg/cm2/s)
65- 70 F6.2 --- I [0.03/293] Extinction corrected flux
normalized to F(Hβ)=100
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Acknowledgements:
Marcin Hajduk, cinek(at)ncac.torun.pl
(End) Patricia Vannier [CDS] 12-Mar-2014