J/MNRAS/480/4589 Extreme abundance discrepancy factors in PNe (Wesson+, 2018)
Confirmation of the link between central star binarity and extreme abundance
discrepancy factors in planetary nebulae.
Wesson R., Jones D., Garcia-Rojas J., Boffin H.M.J., Corradi R.L.M.
<Mon. Not. R. Astron. Soc., 480, 4589-4613 (2018)>
=2018MNRAS.480.4589W 2018MNRAS.480.4589W (SIMBAD/NED BibCode)
ADC_Keywords: Abundances ; Mass loss ; Interstellar medium ; Planetary nebulae ;
Stars, double and multiple
Keywords: circumstellar matter - stars: mass-loss - stars: winds, outflows -
ISM: abundances - planetary nebulae: general - binaries: close
Abstract:
It has recently been noted that there seems to be a strong correlation
between planetary nebulae with close binary central stars and highly
enhanced recombination line abundances. We present new deep spectra of
seven objects known to have close binary central stars, and find that
the heavy element abundances derived from recombination lines exceed
those from collisionally excited lines by factors of 5-95, placing
several of these nebulae among the most extreme known abundance
discrepancies. This study nearly doubles the number of nebulae known
to have a binary central star and an extreme abundance discrepancy. A
statistical analysis of all nebulae with measured recombination line
abundances reveals no link between central star surface chemistry and
nebular abundance discrepancy, but a clear link between binarity and
the abundance discrepancy, as well as an anticorrelation between
abundance discrepancies and nebular electron densities: all nebulae
with a binary central star with a period of less than 1.15d have an
abundance discrepancy factor exceeding 10, and an electron density
less than ∼1000cm-3; those with longer period binaries have
abundance discrepancy factors less than 10 and much higher electron
densities. We find that [OII] density diagnostic lines can be strongly
enhanced by recombination excitation, while [SII] lines are not. These
findings give weight to the idea that extreme abundance discrepancies
are caused by a nova-like eruption from the central star system,
occuring soon after the common-envelope phase, which ejects material
depleted in hydrogen, and enhanced in CNONe but not in third-row
elements.
Description:
We obtained observations of 42 planetary nebulae in ESO programmes
093.D-0038(A) and 096.D-0080(A). The nebulae in our sample were
southern hemisphere objects selected from a list of PNe with close
binary central stars. The observations were carried out during service
time with the FORS2 instrument mounted on the ESO VLT's UT1 Antu
telescope (Appenzeller et al. 1998Msngr..94....1A 1998Msngr..94....1A). The programmes
were designated as filler programmes, designed to be performed under
any conditions, including periods of bad weather (seeing greater than
2' and/or clouds). Because of this, a number of our targets were
observed during times of poor seeing and transparency, and nebular
emission was sometimes only very weakly detected. We detected strong
recombination line emission in 8 objects, while in 20 objects, the
spectra were deep enough to obtain collisionally excited line
abundances but not recombination line abundances. In 14 objects, no
abundances could be measured.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table5.dat 60 20 Estimated upper limits to the abundance
discrepancy factor in the cases where CEL
abundances could be calculated but no
recombination lines were detected
table6.dat 56 15 Properties of the 15 nebulae with close binary
central stars and a measured adf
tablea1.dat 45 76 Observing log
tableb1.dat 120 3275 Observed and dereddened line fluxes
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See also:
J/MNRAS/368/1959 : Chemical abundances for Hf 2-2 (Liu+, 2006)
Byte-by-byte Description of file: table5.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Name Object name
11- 14 F4.1 10-3 RLO2/H Upper limits for the RL abundances of O2+/H+
16- 19 F4.2 10-3 CELO2/H Observed CEL abundances of O2+/H+
21 A1 --- l_adf adf upper limit
23- 25 I3 --- adf Upper limit to the abundance discrepancy
factor
27- 32 F6.3 d Porb Orbital period
34- 37 I4 cm-3 Ne[SII] ? Electron density from [SII]
39- 42 I4 cm-3 E_Ne[SII] ? Upper error on Ne[SII]
44- 46 I3 cm-3 e_Ne[SII] ? Lower error on Ne[SII]
48- 51 I4 cm-3 Ne[OII] ? Electron density from [OII]
53- 56 I4 cm-3 E_Ne[OII] ? Upper error on Ne[OII]
58- 60 I3 cm-3 e_Ne[OII] ? Lower error on Ne[OII]
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Name Object name
11- 16 F6.2 --- adf Abundance discrepancy factor
18- 21 F4.1 --- E_adf ? Upper error on adf
23- 26 F4.1 --- e_adf ? Lower error on adf
28- 32 F5.3 d P Binary orbital period
34 A1 --- u_P [ ?] Uncertainty on P
36- 39 F4.2 --- N/H N/H abundance
41- 44 F4.2 --- O/H O/H abundance
46 A1 --- u_Ne [ ~] Uncertainty on Ne
48- 52 I5 cm-3 Ne Electron density
54- 56 A3 --- Ref References (1)
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Note (1): References as follows:
a = This work
b = Corradi et al. (2015ApJ...803...99C 2015ApJ...803...99C)
c = Jones et al. (2015A&A...580A..19J 2015A&A...580A..19J, Cat. J/A+A/580/A19)
d = Liu et al. (2006MNRAS.368.1959L 2006MNRAS.368.1959L, Cat. J/MNRAS/368/1959)
e = Sowicka et al. (2017MNRAS.471.3529S 2017MNRAS.471.3529S)
f = Garcia-Rojas et al. (2013A&A...558A.122G 2013A&A...558A.122G)
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Byte-by-byte Description of file: tablea1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 13 A13 --- Name Object name
15- 18 I4 deg PA [] Position angle
20- 24 A5 --- Grism Grism (GRIS_1200B, GRIS_1200R or
GRIS_600RI grisms)
26- 29 I4 s ExpTime Exposure time
31- 39 F9.3 d MJD Modified Julian Date
41- 45 F5.3 --- Airmass Airmass
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Byte-by-byte Description of file: tableb1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Name Object name
10- 15 F6.2 arcsec LDist ? Lower value of distance interval
from central star
17- 22 F6.2 arcsec UDist ? Upper value of distance interval from
central star
24- 30 F7.2 0.1nm lambda ? Wavelength
32- 38 F7.2 0.1nm lambdaIon Ion wavelength
40- 47 F8.3 --- F(lambda) ? Observed flux (1)
49- 54 F6.3 --- e_F(lambda) ? Observed flux error (1)
56- 63 F8.3 --- I(lambda) ? Integrated flux (1)
65- 70 F6.3 --- e_I(lambda) ? Integrated flux error (upper value) (1)
72- 77 F6.3 --- E_I(lambda) ? Integrated flux error (lower value) (1)
79- 91 A13 --- Ion Ion
93- 96 A4 --- Mult Multiplet
98-105 A8 --- Lterm Lower term
107-114 A8 --- Uterm Upper term
116-117 I2 --- g1 ? g1 value
119-120 I2 --- g2 ? g2 value
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Note (1): Fluxes on a scale where F(Hβ)=100.
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 31-May-2022