J/MNRAS/496/832 The SDSS/APOGEE catalogue of HgMn stars (Chojnowski+, 2020)
The SDSS/APOGEE catalogue of HgMn stars.
Chojnowski S.D., Hubrig S., Hasselquist S., Beaton R.L., Majewski S.R.,
Garcia-Hernandez D.A., Decolibus D.
<Mon. Not. R. Astron. Soc., 496, 832-850 (2020)>
=2020MNRAS.496..832C 2020MNRAS.496..832C (SIMBAD/NED BibCode)
ADC_Keywords: Stars, peculiar ; Stars, double and multiple ;
Equivalent widths ; Radial velocities ; Rotational velocities ;
Spectral types ; Binaries, orbits ; Spectra, infrared
Keywords: stars: chemically peculiar - stars: binaries: spectroscopic -
stars: rotation
Abstract:
We report on H-band spectra of chemically peculiar Mercury-Manganese
(HgMn) stars obtained via the SDSS/APOGEE survey. As opposed to other
varieties of chemically peculiar stars such as classical Ap/Bp stars,
HgMn stars lack strong magnetic fields and are defined by extreme
overabundances of Mn, Hg, and other heavy elements. A satisfactory
explanation for the abundance patterns remains to be determined, but
low rotational velocity is a requirement and involvement in
binary/multiple systems may be as well. The APOGEE HgMn sample
currently consists of 269 stars that were identified among the
telluric standard stars as those whose metallic absorption content is
limited to or dominated by the H-band MnII lines. Due to the fainter
magnitudes probed by the APOGEE survey as compared to past studies,
only 9/269 stars in the sample were previously known as HgMn types.
The 260 newly identified HgMn stars represents a more than doubling of
the known sample. At least 32 per cent of the APOGEE sample are found
to be binary or multiple systems, and from multi-epoch spectroscopy,
we were able to determine orbital solutions for at least one component
in 32 binaries. Many of the multilined systems include chemically
peculiar companions, with noteworthy examples being the HgMn+Ap/Bp
binary HD 5429, the HgMn+HgMn binary HD 298641, and the HgMn+BpMn+Am
triple system HD 231263. As a further peculiarity, roughly half of the
sample produces narrow emission in the CI 16895Å line, with widths
and radial velocities that match those of the MnII lines.
Description:
The APOGEE instruments are 300-fibre, R=22500, H-band spectrographs
that operate on the Sloan 2.5m telescope (Gunn et al.
2006AJ....131.2332G 2006AJ....131.2332G) at Apache Point Observatory (APO, APOGEE-N) and
on the Du Pont 2.5m telescope (Bowen & Vaughan 1973ApOpt..12.1430B 1973ApOpt..12.1430B) at
Las Campanas Observatory (LCO, APOGEE-S). Each APOGEE instrument
records most of the H-band on three detectors, with coverage gaps
between 15800-15860Å and 16430-16480Å (Wilson et al.
2019PASP..131e5001W 2019PASP..131e5001W) and with each fibre subtending a ∼2arcsec
diameter on-sky field of view.
We also obtained optical spectra of 32 newly discovered HgMn stars, 15
previously known HgMn stars, and Vega using the Astrophysical Research
Consortium Echelle Spectrograph (ARCES; Wang et al.
2003SPIE.4841.1145W 2003SPIE.4841.1145W) on the ARC 3.5m telescope at APO. In each
exposure, ARCES covers the full optical spectrum (3500-10400Å) at
a resolution of R=31500.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 152 269 Summary of the APOGEE HgMn sample
table2.dat 42 24 Atomic data for lines detected in the APOGEE
spectra of HgMn stars, including the hydrogen
Brackett series lines (H-Br)
table3.dat 73 1590 Radial velocity data
table4.dat 132 21 Orbital solutions for SB1s
table5.dat 135 24 Orbital solutions for SB2s and SB3s
table6.dat 116 23 Summary of double-lined and triple-lined
spectroscopic binaries
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- Name 2MASS source identifier (HHMMSSss+DDMMSSs)
18- 29 A12 --- OName Alternative name
31- 36 F6.3 mag Hmag 2MASS H-band magnitude
38- 40 I3 --- S/N ? Signal to noise ratio
42- 43 I2 --- NRV Number of radial velocity measurements
45- 46 I2 --- Nobs Number of observed spectra
48- 49 I2 km/s vsini ? Rotational velocity
51- 52 I2 km/s e_vsini ? Error on vsini
54- 56 I3 10-4nm EWMnII ? Average equivalent width of MnII 15413Å
58- 59 I2 10-4nm EWCeIII ? Average equivalent width of CeIII 15961Å
61- 63 I3 10-4nm EWCI ? Average equivalent width of CI 16895Å
65- 69 F5.1 km/s RV ? Average radial velocity
71- 74 F4.1 km/s e_RV ? Error on RV
76- 80 F5.1 km/s RVscat ? Maximum observed radial velocity minus the
minimum observed radial velocity
82- 85 A4 --- BinType Indication of binarity (1)
87 A1 --- f_BinType Flag on BinType (2)
89- 98 A10 --- SpType Spectral type
100- 152 A53 --- r_SpType Reference for SpType
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Note (1): Binary type as follows:
SB1 = Single-lined binary
SB2 = Double-lined binary
SB2? = Possible double-lined binary
Note (2): Flag as follows:
* = An orbital solution is reported in this paper
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- Ion Ion name
8- 16 F9.3 0.1nm lambda Vacuum wavelength
18- 23 F6.3 [-] loggf Logarithm of the product of statistical
weight and oscillator strength
25- 30 F6.3 eV Elo Lower state energy
32- 37 F6.3 eV Ehi Upper state energy
39- 42 F4.2 --- EW/EW15413 ? Average equivalent width ratio of the
line over MnII 15413Å
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- Name 2MASS source identifier (HHMMSSss+DDMMSSs)
18- 25 F8.3 d HJD Heliocentric Julian date (HJD-245000)
27- 32 A6 --- Inst Instrument (APOGEE or ARCES)
34- 40 F7.2 km/s RV1 ? Radial velocity of the primary star
42- 46 F5.2 km/s e_RV1 Error on RV1
48- 54 F7.2 km/s RV2 ? Radial velocity of the secondary star
56- 60 F5.2 km/s e_RV2 ? Error on RV2
62- 68 F7.2 km/s RV3 ? Radial velocity of the tertiary star
70- 73 F4.2 km/s e_RV3 ? Error on RV3
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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- 16 A16 --- Name 2MASS source identifier (HHMMSSss+DDMMSSs)
18- 19 I2 --- NRV Number of radial velocity measurements
21- 27 F7.3 d P Orbital period
29- 33 F5.3 d e_P Error on P
35- 42 F8.3 d Tmax Epoch of maximum radial velocity (HJD-245000)
44- 48 F5.3 d e_Tmax Error on Tmax
50- 54 F5.3 --- e Orbital eccentricity
56- 60 F5.3 --- e_e Error on e
62- 68 F7.3 deg omega Argument of the periastron
70- 74 F5.3 deg e_omega Error on omega
76- 82 F7.3 km/s gamma Systemic radial velocity
84- 88 F5.3 km/s e_gamma Error on gamma
90- 95 F6.3 km/s K1 Radial velocity semi-amplitude of the primary
star
97- 101 F5.3 km/s e_K1 Error on K1
103- 107 F5.3 AU a1sini Semimajor axis of the primary star
109- 113 F5.3 AU e_a1sini Error on a1sini
115- 119 F5.3 Msun fM1M2 Mass function
121- 125 F5.3 Msun e_fM1M2 Error on fM1M2
127- 132 F6.3 --- chi2 Reduced chi-squared
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 17 A17 --- Name 2MASS source identifier (HHMMSSss+DDMMSSsA)
19- 20 I2 --- NRV Number of radial velocity measurements
22- 28 F7.3 d P ? Orbital period
30- 34 F5.3 d e_P ? Error on P
36- 43 F8.3 d Tmax ? Epoch of maximum radial velocity (HJD-245000)
45- 49 F5.3 d e_Tmax ? Error on Tmax
51- 55 F5.3 --- e ? Orbital eccentricity
57- 61 F5.3 --- e_e ? Error on e
63- 69 F7.3 deg omega ? Argument of the periastron
71- 76 F6.3 deg e_omega ? Error on omega
78- 84 F7.3 km/s gamma ? Systemic radial velocity
86- 90 F5.3 km/s e_gamma ? Error on gamma
92- 98 F7.3 km/s K ? Radial velocity semi-amplitude
100- 104 F5.3 km/s e_K ? Error on K
106- 110 F5.3 AU asini ? Semimajor axis
112- 116 F5.3 AU e_asini ? Error on asini
118- 122 F5.3 Msun Msini3 ? Dynamical mass
124- 128 F5.3 Msun e_Msini3 ? Error on Msini3
130- 135 F6.3 --- chi2 ? Reduced chi-squared
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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- 16 A16 --- Name 2MASS source identifier (HHMMSSss+DDMMSSs)
18- 28 A11 --- Type Companion type
30- 34 F5.1 d P ? Orbital period
36- 40 F5.3 --- M2/M1 ? Mass ratio M2/M1
42 A1 --- u_F2/F1 [~] Uncertainty flag on F2/F1
44- 48 F5.3 --- F2/F1 ? Flux ratio of MgII 4481Å
50- 54 F5.3 --- F2/F12 ? Other value of F2/F1
56- 57 I2 km/s vsini1 Rotational velocity of the primary star
59- 60 I2 km/s e_vsini1 Error on vsini1
62 A1 --- u_vsini2 [~] Uncertainty flag on vsini2
64- 66 I3 km/s vsini2 ? Rotational velocity of the secondary star
68- 69 I2 km/s e_vsini2 ? Error on vsini2
71- 72 I2 km/s vsini3 ? Rotational velocity of the tertiary star
74 I1 km/s e_vsini3 ? Error on vsini3
76- 116 A41 --- Note Remarks
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 28-Jun-2023