J/MNRAS/514/1217 Abundances of the planetary nebula IC 4997 (Danehkar+, 2022)
Physical conditions and chemical abundances of the variable planetary nebula
IC 4997.
Danehkar A., Parthasarathy M.
<Mon. Not. R. Astron. Soc., 514, 1217-1230 (2022)>
=2022MNRAS.514.1217D 2022MNRAS.514.1217D (SIMBAD/NED BibCode)
ADC_Keywords: Planetary nebulae ; Spectroscopy ; Abundances
Keywords: planetary nebulae - IC 4997 - interstellar medium -
chemical abundances - variable stars
Abstract:
The planetary nebula (PN) IC 4997 is one of a few rapidly evolving
objects with variable brightness and nebular emission around a
hydrogen-deficient star. In this study, we have determined the
physical conditions and chemical abundances of this object using the
collisionally excited lines (CELs) and optical recombination lines
(ORLs) measured from the medium-resolution spectra taken in 2014 July
with the FIbre-fed Echelle Spectrograph on the Nordic Optical
Telescope at La Palma Observatory. We derived electron densities of
~>3x104cm-3 and electron temperatures of ~>14000K from CELs,
whereas cooler temperatures of ∼11000 and ∼7000K were obtained from
helium and heavy element ORLs, respectively. The elemental abundances
deduced from CELs point to a metal-poor progenitor with [O/H]≲-0.75,
whereas the ORL abundances are slightly above the solar metallicity,
[O/H]∼0.15. Our abundance analysis indicates that the abundance
discrepancy factors (ADFs=ORLs/CELs) of this PN are relatively
large: ADF(O2+)≳8 and ADF(N2+)≳7. Further research is needed to
find out how the ADFs and variable emissions are formed in this object
and whether they are associated with a binary companion or a very late
thermal pulse.
Description:
Table A1 lists observed and dereddened line fluxes of the planetary
nebula IC 4997 measured by the FIbre-fed Echelle Spectrograph (FIES)
on the Nordic Optical Telescope, on a scale relative to Hb, where
Hb=100.
Table 3 presents interstellar extinctions derived from the Balmer
lines.
Table 5 presents electron temperatures and densities derived from CELs
and ORLs.
Table 6 presents ionic abundances relative to hydrogen derived from
CELs.
Table 7 presents ionic abundances relative to hydrogen derived from
ORLs.
Table 8 presents mean ionic and total elemental abundances derived
from ORLs and CELs.
Objects:
----------------------------------------------------------
RA (2000) DE Designation(s)
----------------------------------------------------------
20 20 08.76 +16 43 53.7 PNG058.3-10.9 = IC 4997
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File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
tablea1.dat 161 102 Observed and dereddened line fluxes (Appendix A)
table3.dat 96 11 Extinctions derived from the Balmer lines
table5.dat 113 14 Temperatures and densities from CELs and ORLs
table6a.dat 103 28 Ionic abundances derived from CELs (condition a)
table6b.dat 103 28 Ionic abundances derived from CELs (condition b)
table7.dat 103 27 Ionic abundances derived from ORLs
table8a.dat 95 58 Mean ionic and total abundances (condition a)
table8b.dat 95 58 Mean ionic and total abundances (condition b)
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See also:
J/A+A/280/581 : Chemical abundances of PNe (Pasquali+, 1993)
J/A+A/282/436 : Abundance gradients from disk PNs (Maciel+ 1994)
J/A+AS/126/297 : PN abundances (Ratag+ 1997)
J/A+A/345/629 : Abundance gradients in planetary nebulae (Maciel+, 1999)
J/A+A/380/300 : Abundances of PN towards Galactic bulge (Escudero+, 2001)
J/A+A/423/199 : Chemical abundances of planetary nebulae (Costa+, 2004)
J/A+A/427/231 : Abundances in planetary nebulae (Gorny+, 2004)
J/MNRAS/349/793 : Galactic PNe abundances (Perinotto+, 2004)
J/A+A/463/265 : Chemical compositions of 48 WR planetary nebulae
(Girard+ 2007)
J/A+A/494/591 : Abundances in planetary nebulae (Chiappini+, 2009)
J/A+A/500/1089 : Abundances in planetary nebulae (Gorny+, 2009)
J/PAZh/35/574 : He, C, N and O abundances in PNe (Milanova+, 2009)
J/ApJ/724/748 : Galactic anticenter PNe and oxygen abundance (Henry+, 2010)
J/A+A/538/A54 : Spectroscopy of 12 [WC] planetary nebulae
(Garcia-Rojas+ 2012)
J/A+A/567/A12 : Chemical abundances in Galactic PNe (Garcia-Hernandez+, 2014)
J/ApJS/257/58 : Properties of [WR] planetary nebulae (Danehkar, 2021)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 13 A13 --- PNG PNG name (PNGLLL.l+BB.b)
15- 27 A13 --- Name Name
29- 32 A4 --- Ref Reference of observed flux (empty column)
34- 40 F7.2 0.1nm lambdaLab Laboratory wavelength (inAngstrom)
43- 52 A10 --- Ion Ion
54- 60 F7.2 0.1nm lambdaObs Observed wavelength (inAngstrom)
63- 69 F7.3 --- F(lambda) Observed flux (in units of F(Hb)=100)
74- 77 F4.1 % e_F(lambda) Formal 1-sigma and noise of observed flux
79- 85 F7.3 --- I(lambda) Dereddened intensity (in units of I(Hb)=100)
91- 94 F4.1 % e_I(lambda) Lower 90% error of dereddened intensity
96- 99 F4.1 % E_I(lambda) Upper 90% error of dereddened intensity
102-109 A8 --- Mult Multiplet (H: Balmer, V: ORLs, F: CELs)
111-126 A16 --- LowTerm Lower term of transition
128-143 A16 --- UpTerm Upper term of transition
145-152 A8 --- g1 Statistical weight of lower level
154-161 A8 --- g2 Statistical weight of upper level
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 13 A13 --- PNG PNG name (PNGLLL.l+BB.b)
15- 27 A13 --- Name Name
29- 38 A10 --- Line Line (H I single, H I Mean)
40- 46 F7.2 0.1nm lambdaLab ? Laboratory wavelength (in Angstrom)
49- 52 A4 --- Mult Balmer multiplet
56- 57 I2 --- Wght ? Weight used for mean abundance (1)
60- 70 E11.6 --- Ext Extinction
73- 83 E11.6 --- e_Ext Lower 90% error of Extinction
86- 96 E11.6 --- E_Ext Upper 90% error of Extinction
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Note (1): The weights calculated based on the He I theoretical predictions
are used for calculating the mean extinction.
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 13 A13 --- PNG PNG name (PNGLLL.l+BB.b)
15- 27 A13 --- Name Name
29- 33 A5 --- Type Type (Te, Te_rc, Ne) (1)
35- 44 A10 --- Ion Ion
46- 85 A40 --- Diagnos Diagnostic lines
87- 92 I6 --- Value Value (Te: Temperature or Ne: Density) (2)
99-103 I5 --- e_Value Lower 90% error of Value
109-113 I5 --- E_Value ? Upper 90% error of Value
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Note (1): The symbol "rc" indicates that the auroral lines are corrected for
recombination contribution.
Note (2): O II ORLs 4119.22, 4153.30, 4319.63, 4349.43, 4416.97, 4609.44,
4610.20, 4641.81, 4649.13, 4650.84, 4661.63, and 4676.24 are used
for the O II least-squares minimization.
N II ORLs 4630.54, 5666.63, 5676.02, and 5679.56 are used for
the N II least-squares minimization.
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Byte-by-byte Description of file: table6a.dat table6b.dat table7.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 13 A13 --- PNG PNG name (PNGLLL.l+BB.b)
15- 27 A13 --- Name Name
29- 40 A12 --- Ion Ion
42- 51 A10 --- Line Line
53- 59 F7.2 0.1nm lambaLab Laboratory wavelength (in Angstrom)
62- 63 I2 --- Wght Weight used for mean abundance (1)
67- 77 E11.6 --- Abund Abundances relative to Hydrogen (2)
81- 91 E11.6 --- e_Abund Lower 90% error of Abundance
93-103 E11.6 --- E_Abund Upper 90% error of Abundance
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Note (1): The weights are calculated based on the predicted intrinsic fluxes.
Note (2): condition for table6a:
Te([O I]), Te,rc([N II]), and Te([Ar III]) adopted for X0, X+ and Xi+ (i > 2),
respectively; and Ne([O II]) and Ne([Cl III]) assumed for Xi+(i = 0, 1) and
Xi+ (i > 2), respectively.
condition for table6b:
The same as the condition (a), except for Te([O III]) and Ne([Ar IV]) used
for Xi+ (i > 2).
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Byte-by-byte Description of file: table8a.dat table8b.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 13 A13 --- PNG PNG name (PNGLLL.l+BB.b)
15- 27 A13 --- Name Name
29- 40 A12 --- Ion Ion (Mean ionic, total, icf) (1)
42- 48 A7 --- Type Type (ORL, CEL)
50- 57 A8 --- Ref-icf References for icf formulas (3)
59- 69 E11.6 --- Abund Abundances relative to Hydrogen (2)
73- 83 E11.6 --- e_Abund Lower 90% error of Abundance
85- 95 E11.6 --- E_Abund Upper 90% error of Abundance
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Note (1): condition for table8a: Te([O I]), Te,rc([N II]), and Te([Ar III])
adopted for X0, X+ and Xi+ (i > 2), respectively; and Ne([O II]) and
Ne([Cl III]) assumed for Xi+(i = 0, 1) and Xi+ (i > 2), respectively.
condition for table8b: The same as the condition (a), except for
Te([O III]) and Ne([Ar IV]) used for Xi+ (i > 2).
Note (2): [N II] 5754.60 and [O III] 4363.21 are not used for the mean ionic
abundances.
Note (3): References for icf formulas are as follows:
DMS14 = Delgado-inglada et al. (2014MNRAS.440..536D 2014MNRAS.440..536D)
ITL94 = Izotov et al. (1994ApJ...435..647I 1994ApJ...435..647I)
KB94 = Kingsburgh & Barlow (1994MNRAS.271..257K 1994MNRAS.271..257K)
L00 = Liu et al. (2000MNRAS.312..585L 2000MNRAS.312..585L)
WL07 = Wang & Liu (2007MNRAS.381..669W 2007MNRAS.381..669W)
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Acknowledgements:
Ashkbiz Danehkar, ashkbiz.danehkar(at)gmail.com
(End) Ashkbiz Danehkar [Michigan, USA], Patricia Vannier [CDS] 19-Jul-2022