J/AJ/159/9 HD 150382 lithium-rich star at the early-AGB stage (Holanda+, 2020)
HD 150382: a lithium-rich star at the early-AGB stage?
Holanda N., Drake N.A., Pereira C.B.
<Astron. J., 159, 9 (2020)>
=2020AJ....159....9H 2020AJ....159....9H (SIMBAD/NED BibCode)
ADC_Keywords: Stars, giant ; Effective temperatures ; Abundances ;
Rotational velocities ; Equivalent widths
Keywords: Lithium stars - Chemically peculiar stars - A giant stars -
Asymptotic giant branch stars - High resolution spectroscopy
Abstract:
We report the discovery of a lithium-rich giant, HD 150382, a
post-red-giant-branch clump star. The atmospheric parameters, the chemical
abundances for 17 elements, and the isotopic ratio 12C/13C were
determined using the equivalent width and the spectral synthesis methods.
The lithium abundance was determined via spectral synthesis of the Li I
resonance doublet at λ 6708 yielding logε(Li)NLTE=2.55.
The excited-state line at λ 6104 also was analyzed. In addition,
we have used theoretical evolutionary tracks to determine the mass and
luminosity of HD 150382 and compare it with other well-known lithium-rich
giants in the literature. Our results show that HD 150382 is a slowly
rotating K-giant star having near-solar metallicity. We also show that
HD 150382 is not s-process enriched, which is in agreement with its
evolutionary status. Finally, based on the abundance results, we study
the possible scenarios of the lithium enrichment.
Description:
The spectroscopic observation was carried out on 2016 April 11, and
was made using the Fiber-fed Extended Range Optical Spectrograph (FEROS;
Kaufer et al. 1999Msngr..95....8K 1999Msngr..95....8K) at the 2.2 m Max Planck
Gesellschaft/European Southern Observatory (ESO) Telescope in La Silla,
Chile. The FEROS provides a resolving power of R∼48000 and a full
wavelength coverage between 3800-9200 Å. The exposure time for HD 150382
was 300 s to a typical signal-to-noise ratio (S/N)=100-150. Further, the
reduction was performed using the FEROS Data Reduction System pipeline.
Table 5 shows the stellar spectroscopic parameters and abundances for
comparison with our results. These stars are lithium-rich giants well-known
in the literature.
Objects:
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RA (ICRS) DE Designation(s)
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16 41 07.80 -11 50 19.0 HD 150382 = HIP 81680
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table5.dat 64 84 Properties of the Li-rich giants adopted for
comparison
table6.dat 29 98 List of spectral lines with atomic parameters
and equivalent width (EW)
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See also:
J/A+A/364/674 : Li-rich giants atomic lines (Castilho+, 2000)
J/A+AS/142/275 : Stellar activity of late-type stars (Strassmeier+, 2000)
Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 18 A18 --- Name Star name
20 A1 --- f_Name [a] Flag on Name (1)
22- 25 I4 K Teff [3460/5100] Effective temperature
27- 30 F4.2 [cm/s2] logg [0.6/3.79] Surface gravity
32- 36 F5.2 [-] [Fe/H] [-0.53/0.38] Metallicity
38- 41 F4.2 [-] A(Li) [1.5/4.22] Lithium abundance, logε(Li)
43- 44 A2 --- l_vsini [< =] Limit flag on vsini
45- 48 F4.1 km/s vsini [1/37.1]? Rotational velocity
50- 53 F4.1 [-] 12C/13C [4.3/28]? 12C/13C ratio
55- 64 A10 --- Ref Reference(s) (2)
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Note (1): Flag as follows:
a = Object in the early-AGB stage.
Note (2): Reference as follows:
TT17 = Takeda & Tajitsu (2017PASJ...69...74T 2017PASJ...69...74T);
ST00 = Strassmeier et al. (2000, J/A+AS/142/275);
GD89 = Gratton & D'Antona (1989A&A...215...66G 1989A&A...215...66G);
DS95 = da Silva et al. (1995ApJ...448L..41D 1995ApJ...448L..41D);
RL05 = Reddy & Lambert (2005AJ....129.2831R 2005AJ....129.2831R);
RL16 = Reddy & Lambert (2016A&A...589A..57R 2016A&A...589A..57R);
KR09 = Kumar & Reddy (2009ApJ...703L..46K 2009ApJ...703L..46K);
KR11 = Kumar et al. (2011ApJ...730L..12K 2011ApJ...730L..12K);
CA00 = Castilho et al. (2000, J/A+A/364/674);
DR02 = Drake et al. (2002AJ....123.2703D 2002AJ....123.2703D);
AL11 = Alcala et al. (2011A&A...531L..12A 2011A&A...531L..12A);
CA16 = Casey et al. (2016MNRAS.461.3336C 2016MNRAS.461.3336C);
SM18 = Smiljanic et al. (2018A&A...617A...4S 2018A&A...617A...4S);
FC93 = Not described in this paper;
JA99 = Sackmann & Boothroyd (1999ApJ...510..217S 1999ApJ...510..217S);
DR02 = Drake et al. (2002AJ....123.2703D 2002AJ....123.2703D).
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 5 A5 --- El Element
7- 13 F7.2 0.1nm lambda [4562.37/8772.88] Wavelength λ (Å)
15- 18 F4.2 eV chi [0/5.94] Excitation potential χ
20- 25 F6.3 [-] loggf [-5.95/0.42] Oscillator strength
27- 29 I3 0.1pm EW [30/154] Equivalent width (mÅ)
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History:
From electronic version of the journal
(End) Tiphaine Pouvreau [CDS] 12-Feb-2020