J/AJ/151/85 Companions to APOGEE stars. I. (Troup+, 2016)
Companions to APOGEE stars.
I. A Milky Way-spanning catalog of stellar and substellar companion candidates
and their diverse hosts.
Troup N.W., Nidever D.L., De Lee N., Carlberg J., Majewski S.R.,
Fernandez M., Covey K., Chojnowski S.D., Pepper J., Nguyen D.T.,
Stassun K., Nguyen D.C., Wisniewski J.P., Fleming S.W., Bizyaev D.,
Frinchaboy P.M., Garcia-Hernandez D.A., Ge J., Hearty F., Meszaros S.,
Pan K., Allende Prieto C., Schneider D.P., Shetrone M.D., Skrutskie M.F.,
Wilson J., Zamora O.
<Astron. J., 151, 85 (2016)>
=2016AJ....151...85T 2016AJ....151...85T (SIMBAD/NED BibCode)
ADC_Keywords: Milky Way ; Stars, double and multiple ; Photometry, infrared ;
Proper motions ; Effective temperatures ; Stars, masses ;
Abundances, [Fe/H] ; Stars, distances ; Radial velocities
Keywords: binaries: close - binaries: spectroscopic - brown dwarfs -
Galaxy: stellar content - planetary systems
Abstract:
In its three years of operation, the Sloan Digital Sky Survey Apache
Point Observatory Galactic Evolution Experiment (APOGEE-1) observed
>14000 stars with enough epochs over a sufficient temporal baseline
for the fitting of Keplerian orbits. We present the custom orbit-fitting
pipeline used to create this catalog, which includes novel quality
metrics that account for the phase and velocity coverage of a fitted
Keplerian orbit. With a typical radial velocity precision of ∼100-200 m/s,
APOGEE can probe systems with small separation companions down to a
few Jupiter masses. Here we present initial results from a catalog of
382 of the most compelling stellar and substellar companion candidates
detected by APOGEE, which orbit a variety of host stars in diverse
Galactic environments. Of these, 376 have no previously known small
separation companion. The distribution of companion candidates in this
catalog shows evidence for an extremely truncated brown dwarf (BD) desert
with a paucity of BD companions only for systems with a<0.1-0.2 AU,
with no indication of a desert at larger orbital separation. We propose
a few potential explanations of this result, some which invoke this
catalog's many small separation companion candidates found orbiting
evolved stars. Furthermore, 16 BD and planet candidates have been
identified around metal-poor ([Fe/H]←0.5) stars in this catalog, which
may challenge the core accretion model for companions >10 MJup.
Finally, we find all types of companions are ubiquitous throughout the
Galactic disk with candidate planetary-mass and BD companions to
distances of ∼6 and ∼16 kpc, respectively.
Description:
All APOGEE-1 observations were taken using fibers connected to either
the Sloan 2.5 m telescope (Gunn et al. 2006AJ....131.2332G 2006AJ....131.2332G) or the NMSU
1 m telescope at Apache Point Observatory (APO; Majewski et al.
2017AJ....154...94M 2017AJ....154...94M). In normal use on the Sloan 2.5 m telescope,
APOGEE employs a massively multiplexed, fiber-fed spectrograph capable
of recording 300 spectra at a time. Of the 146000 stars observed in
APOGEE-1, 14840 had at least eight visits; these stars were selected
for analysis here. APOGEE first light observations were obtained in
2011 May and APOGEE-1 observations concluded at the end of SDSS-III in
2014 July, providing a maximum temporal baseline of slightly more than
three years (∼1000 days).
Using refined criteria, 382 stars (55% of the statistically significant
RV variable sample) were selected to be a part of the "gold sample,"
which represent the best-quality companion candidates detected by APOGEE.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 3616 382 APOGEE DR12 Catalog of Companion Candidates
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
V/147 : The SDSS Photometric Catalogue, Release 12 (Alam+, 2015)
J/ApJ/497/736 : The young cluster IC 348. (Herbig, 1998)
J/other/A+ARV/18.67 : Accurate masses and radii of normal stars (Torres+, 2010)
J/ApJS/215/19 : APOKASC catalog of Kepler red giants
(Pinsonneault+, 2014)
J/MNRAS/460/3179 : APOGEE stars distance and extinction (Wang+, 2016)
https://filtergraph.com/apOrbitPub : Filtergraph portal homepage
Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 18 A18 --- Name TMASS-STYLE object name
(2MHHMMSSss+DDMMSSs) (APOGEE_ID)
20- 23 I4 --- Fld-Loc [4102/4586] APOGEE field location number
(LOCATION_ID)
25- 34 A10 --- Fld-Name APOGEE field name (FIELD)
36- 37 I2 --- NRV [9/34] Number of radial velocity
measurements used in the fit (NVISITS)
39- 50 E12.6 --- SNR Median signal-to-noise ratio per pixel
in combined frame (at apStar sampling)
(SNR)
52- 57 F6.3 mag Jmag [8.646/15.631] 2MASS J-band magnitude (J)
59- 63 F5.3 mag e_Jmag [0.018/0.079] Uncertainty in Jmag (J_ERR)
65- 70 F6.3 mag Hmag [8.101/14.112] 2MASS H-band magnitude (H)
72- 76 F5.3 mag e_Hmag [0.016/0.055] Uncertainty in Hmag (H_ERR)
78- 83 F6.3 mag Ksmag [7.959/13.977] 2MASS Ks-band magnitude
(K)
85- 89 F5.3 mag e_Ksmag [0.013/0.061] Uncertainty in Ksmag
(K_ERR)
91- 98 F8.6 mag AK K-band extinction adopted (AK)
100- 116 A17 --- AKMeth Method used to get targeting extinction
(AK_SRC)
118- 127 F10.6 deg RAdeg Right Ascension in decimal degrees
(J2000) (RA)
129- 138 F10.6 deg DEdeg Declination in decimal degrees (J2000)
(DEC)
140- 149 F10.6 deg GLON Galactic longitude (GLON)
151- 160 F10.6 deg GLAT Galactic latitude (GLAT)
162- 166 F5.1 mas/yr pmRA [-82/288] Proper motion along RA (PMRA)
168- 172 F5.1 mas/yr pmDE [-70/124] Proper motion along DE (PMDEC)
174- 180 A7 --- pmCat Catalog used for proper motion (PM_SRC)
182 I1 --- Bitmask [0/1] Bitmask that identifies main survey
target and other classe (EXTRATARG) (1)
184- 194 I11 --- Bitwise1 [-2147483584/0] Bitwise OR of first
APOGEE target flag of all visits
(APOGEE_TARGET1) (1)
196- 206 I11 --- Bitwise2 [-2147482624/0] Bitwise OR of second
APOGEE target flag of all visits
(APOGEE_TARGET2) (1)
208- 293 A86 --- TargFlag Target flag in English (TARGFLAGS)
295- 300 I6 --- StFlag [0/136708] Flag for star condition taken
from bitwise OR of individual visits
(STARFLAG) (1)
302- 378 A77 --- StFlags Star flag in English (STARFLAGS)
380- 383 I4 --- ASPCAP [0/2176] Flag for ASPCAP analysis
(ASPCAPFLAG) (1)
385- 436 A52 --- ASPCAPS ASPCAP flag in English (ASPCAPFLAGS)
438- 446 F9.4 K Teff [3541.8/6532.8] Adopted effective
temperature for the primary star (TEFF)
448- 454 F7.4 K e_Teff [91.4667/91.5] Uncertainty in Teff
(TEFF_ERR)
456- 462 F7.5 [cm/s2] logg [1.12311/5.20282] Adopted surface gravity
for the primary star (in cgs units)
(LOGG)
464- 470 F7.5 [cm/s2] e_logg [0.10689/0.11] Uncertainty in logg
(LOGG_ERR)
472- 480 F9.6 [-] [Fe/H] [-1.8122/0.43027] Adopted metallicity
[Fe/H] for the primary star (FE_H)
482- 489 F8.6 [-] e_[Fe/H] [0.030466/0.056803] Uncertainty in [Fe/H]
(FEHERR)
491 I1 --- Source [1/2] Source of the stellar parameters
adopted (SPARAMTYPE) (2)
493- 495 A3 --- Class Classification applied to host star
(STARTYPE) (3)
497- 504 F8.6 Msun M* [0.382997/8.28768] Mass of the primary
based on the available stellar
parameters (MSTAR)
506- 514 F9.6 Msun e_M* [0.024512/35.632717] Uncertainty in M*
(MSTAR_ERR)
516- 527 E12.7 AU Rad Radius of the primary based on the
available stellar parameters (RSTAR)
529- 540 E12.7 AU e_Rad Uncertainty in Rad (RSTAR_ERR)
542- 551 F10.4 pc Dist Adopted distance of the primary star
(DIST)
553- 561 F9.4 pc e_Dist Uncertainty in Dist (DIST_ERR)
563 I1 --- Meth [0/5] Method of mass/radius/distance
estimation (MSTAR_SRC) (4)
565- 573 F9.5 m/s Jitter [1.37364/415.15521] Estimated intrinsic
radial velocity jitter of the star
(VJITTER)
575- 583 F9.4 d Bmax [22.8964/1116.9731] Maximum baseline of
radial velocity data included in fit
(BASELINE)
585- 594 F10.5 m/s sigmanu [35.95357/2024.13] Median of radial
velocity errors σν (SIGMA_V)
596- 604 F9.5 --- Signi [2.50459/505.59149] Significance of the
radial velocity variations (see
Section 3.1.2) (SIG_RVVAR)
605-1304 50F14.5 d JD ? Julian Date of observation included
in fit (JD)
1305-2004 50F14.5 m/s RV ? Radial velocity of observation included
in fit (RV)
2005-2554 50F11.5 m/s e_RV ? Uncertainty in RV (RV_ERR)
2555-2954 50I8 m/s RVMod [-291933/129398]? Radial velocity of
best-fit orbital model (MODEL)
2955-3404 50F9.2 m/s Resid [-2463.57/5302.25]? Residual of best-fit
orbital model (RESID)
3406-3418 E13.8 d Per Best-fit orbital period of the system
(PERIOD)
3420-3432 E13.8 d e_Per Uncertainty in Per (PERIOD_ERR)
3434-3444 F11.5 m/s K Best-fit radial velocity semiamplitude
of the system (SEMIAMP)
3446-3459 F14.5 m/s e_K ?=0 Uncertainty in K (SEMIAMP_ERR)
3461-3471 E11.6 --- e Best-fit eccentricity of the system (ECC)
3473-3483 E11.6 --- e_e Uncertainty in e (ECC_ERR)
3485-3492 F8.5 deg omega [-3.13937/3.13865] Argument of periastron
ω (OMEGA)
3494-3506 F13.5 d T0 Epoch of transit, in Julian Date
3508-3520 F13.5 d Tperi Epoch of periastron (TPERI)
3522-3534 E13.8 m/s V0 Intercept of the global trend applied to
the radial velocity (V0)
3536-3543 F8.3 m/s/d Slope [-157.833/520.512] Slope of the global
trend applied to the radial velocity
(SLOPE)
3545-3546 I2 --- NIter [5/49] Number of iterations used to
converge on a period (see Section 3.3.2)
(NITER)
3548-3554 F7.3 --- chi2 [0.374/622.205] χ2 (not reduced)
of the fit (CHI2)
3556-3557 I2 --- DOF [4/29] Degrees of freedom of the fit
(DOF)
3559-3568 F10.5 m/s rms [14.7466/2037.35] Root-mean-square of
the residual of the fit (FIT_RMS)
3570-3576 F7.5 --- PUI [0.60977/0.99191] Phase Uniformity Index
(see Section 3.3.4) (PUI)
3578-3584 F7.5 --- VUI [0.52988/0.97134] Velocity Uniformity
Index (see Section 3.3.4) (VUI)
3586-3596 E11.6 Msun fMass Mass function of the system (MASSFN)
3598-3608 E11.6 Msun msini Estimated msini of the companion
(see Section 3.3.3) (MSINI)
3610-3616 F7.5 AU a [0.00589/3.59101] Estimated orbital
semimajor axis of the companion
(SEMIMAJ)
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Note (1): See http://www.sdss.org/dr12/algorithms/bitmasks/ for APOGEE bitmask
definitions.
Note (2): Source as follows:
1 = Uncalibrated APOGEE Stellar Parameters and Chemical Abundances pipeline
(ASPCAP);
2 = RV mini-grid (see Section 3.2). The APOGEE reduction pipeline initially
selects, through χ2 minimization, an RV template from a coarse grid
of synthetic spectra (the "RV mini-grid").
Note (3): We divide the stars in this sample into 5 classes defined by the
following crteria:
PMS = Pre-main Sequence: Stars flagged in APOGEE as young stellar cluster
members (IC 348 and Orion);
RC = Red Clump: Stars in the APOGEE RC Catalog (Bovy et al.
2014ApJ...790..127B 2014ApJ...790..127B);
RG = Red Giant: Stars not selected as RC or PMS stars with Teff<5500 K,
log g<3.7+0.1[Fe/H]. The second relation was derived by mapping the
log g of the base of the giant branch as a function of [Fe/H] from
Dartmouth isochrones (Chaboyer et al. 2008ApJS..178...89D 2008ApJS..178...89D) for typical
ages expected of APOGEE giants;
SG = Subgiant: Stars not selected as RC or PMS stars with Teff>4800 K,
log g≥3.7+0.1[Fe/H], log g<4-(7x10-5)(Teff-8000 K).
The second relation only applies for Teff<5500 K. The third relation
was determined by the log g at the highest Teff of Dartmouth
isochrones at a variety of ages and [Fe/H], roughly mapping the
main-sequence turnoff (MSTO), and fitting a liner function to these
points;
MS = Dwarf: Any star that does not fit into any of the above categories are
classified as MS stars.
Note (4): Method as follows:
0 = Torres et al. (2010, J/other/A+ARv/18.67) relation;
1 = APOGEE-Kepler catalog (APOKASC, Pinsonneault et al. 2014, J/ApJS/215/19);
2 = APOGEE RC Catalog (Bovy et al. 2014ApJ...790..127B 2014ApJ...790..127B);
3 = Spectrophotometric;
4 = TRILEGAL (Girardi et al. 2005A&A...436..895G 2005A&A...436..895G) simulation;
5 = Young cluster distance. The six PMS stars in this sample are located in
the young cluster IC 348 (d=316±22 pc; Herbig 1998, J/ApJ/497/736), so
we adopt the distance to this cluster as the approximate distance to
these stars.
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History:
Prepared via OCR at CDS.
From electronic version of the journal
(End) Sylvain Guehenneux [CDS] 10-Oct-2016