J/ApJ/785/159 SONYC census of substellar objects in Lupus 3 (Muzic+, 2014)
Substellar objects in nearby young clusters (SONYC).
VIII. Substellar population in Lupus 3.
Muzic K., Scholz A., Geers V.C., Jayawardhana R., Lopez Marti B.
<Astrophys. J., 785, 159 (2014)>
=2014ApJ...785..159M 2014ApJ...785..159M (SIMBAD/NED BibCode)
ADC_Keywords: YSOs ; Stars, M-type ; Associations, stellar ; Proper motions ;
Spectral types ; Effective temperatures ; Photometry, infrared
Keywords: brown dwarfs - stars: formation - stars: low-mass -
stars: luminosity function, mass function
Abstract:
SONYC -Substellar Objects in Nearby Young Clusters- is a survey
program to investigate the frequency and properties of substellar
objects in nearby star-forming regions. We present a new imaging and
spectroscopic survey conducted in the young (∼1 Myr), nearby (∼200 pc)
star-forming region Lupus 3. Deep optical and near-infrared images
were obtained with MOSAIC-II and NEWFIRM at the CTIO 4 m telescope,
covering ∼1.4 deg2 on the sky. The i-band completeness limit of 20.3 mag
is equivalent to 0.009-0.02 M☉, for AV≤5. Photometry and
11-12 yr baseline proper motions were used to select candidate
low-mass members of Lupus 3. We performed a spectroscopic follow-up of
123 candidates, using VIMOS at the Very Large Telescope, and we
identify 7 probable members, among which 4 have spectral type later
than M6.0 and Teff≤3000 K, i.e., are probably substellar in nature.
Two of the new probable members of Lupus 3 appear underluminous for
their spectral class and exhibit emission line spectrum with strong
Hα or forbidden lines associated with active accretion. We derive
a relation between the spectral type and effective temperature:
Teff=(4120±175)-(172±26)xSpT, where SpT refers to the M spectral
subtype between 1 and 9. Combining our results with the previous works
on Lupus 3, we show that the spectral type distribution is consistent with
that in other star-forming regions, as well as the derived star-to-brown
dwarf ratio of 2.0-3.3. We compile a census of all spectroscopically
confirmed low-mass members with spectral type M0 or later.
Description:
The near-infrared observations were designed to provide J- and KS-band
photometry in the area slightly larger than the one covered with
MOSAIC-II. We used NEWFIRM at the CTIO 4 m telescope, providing an FOV
of 28'x28' and a pixel scale of 0.4". The NEWFIRM detector is a
mosaic of four 2048x2048 Orion InSb arrays, organized in a 2x2 grid.
Data reduction was performed using the NEWFIRM pipeline. The data were
dark- and sky-subtracted and were corrected for bad pixels and
flat-field effects. The astrometry was calibrated with respect to the
2MASS (Skrutskie et al. 2006AJ....131.1163S 2006AJ....131.1163S, Cat. VII/233) coordinate
system, and each detector quadrant was re-projected onto an
undistorted celestial tangent plane.
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
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16 09.6 -39 03 Lupus 3 = NAME Lupus III
----------------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 128 27 Photometry and Spectral Types for the Objects
of Spectral Type M, or Slightly Earlier,
Identified Toward Lupus 3
table3.dat 34 27 Effective Temperature and Extinction Derived
from Models, for the Objects of Spectral Type M
(or Slightly Earlier) Toward Lupus 3
table4.dat 122 82 Spectroscopically Confirmed Very Low Mass
Members of Lupus 3
--------------------------------------------------------------------------------
See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
J/A+A/454/595 : X-ray emission of T Tau stars in Lupus 3 (Gondoin, 2006)
J/ApJS/177/551 : Spitzer c2d survey of Lupus dark clouds (Merin+, 2008)
J/A+A/500/1045 : Cool stars and brown dwarfs in Lupus clouds (Comeron+, 2009)
J/ApJ/744/6 : SONYC census of very low-mass objects in NGC1333
(Scholz+, 2012)
J/ApJ/744/134 : SONYC new brown dwarfs in ρ Oph (Muzic+, 2012)
J/A+A/561/A2 : 36 accreting YSOs emission lines (Alcala+, 2014)
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- ID SONYC candidate identifier (S-NN) (G1)
6- 7 I2 h RAh Hour of Right Ascension (J2000)
9- 10 I2 min RAm Minute of Right Ascension (J2000)
12- 16 F5.2 s RAs Second of Right Ascension (J2000)
18 A1 --- DE- Sign of the Declination (J2000)
19- 20 I2 deg DEd Degree of Declination (J2000)
22- 23 I2 arcmin DEm Arcminute of Declination (J2000)
25- 28 F4.1 arcsec DEs Arcsecond of Declination (J2000)
30- 33 F4.1 mag imag MOSAIC-II i-band magnitude
35- 38 F4.1 mag Jmag NEWFIRM J-band magnitude
40- 43 F4.1 mag Ksmag NEWFIRM KS-band magnitude
45- 48 F4.1 mag Av Absorption in V band from photometry
50 A1 --- l_SpType [<] Limit flag on SpType
51- 56 A6 --- SpType Spectral type
58- 60 F3.1 mag AvSp ? Absorption in V band from spectral type
62- 66 F5.1 mas/yr pmRA ? Proper motion along RA (pmRA*cosDE)
68- 70 F3.1 mas/yr e_pmRA ? Error on pmRA
72- 76 F5.1 mas/yr pmDE ? Proper motion along DE
78- 80 F3.1 mas/yr e_pmDE ? Error on pmDE
82 A1 --- Cand [yn-] Proper motion candidate (y=yes, n=no)
84- 89 F6.1 0.1nm EW ? Equivalent width of the Hα line
91- 99 A9 --- Memb Cluster membership
101 A1 --- n_Memb [2/3] Note on Memb (1)
103-124 A22 --- Com Comment (2)
126-128 A3 --- r_Com [abcd, ] Comment reference(s) (3)
--------------------------------------------------------------------------------
Note (1): Note as follows:
2 = Background giant;
3 = Field dwarf.
Note (2): Comment as follows:
C09 = Candidate member in Comeron et al. (2009, J/A+A/500/1045), Table 9;
M08 = IRAC YSO candidate from Merin et al. (2008, J/ApJS/177/551);
G06 = X-ray source from Gondoin (2006, J/A+A/454/595).
Note (3): Reference as follows:
a = Comeron et al. 2003A&A...406.1001C 2003A&A...406.1001C;
b = Mortier et al. 2011MNRAS.418.1194M 2011MNRAS.418.1194M;
c = Allen et al. 2007ApJ...655.1095A 2007ApJ...655.1095A;
d = Comeron et al. 2013A&A...554A..86C 2013A&A...554A..86C.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 4 A4 --- ID SONYC candidate identifier (S-NN) (G1)
6 A1 --- l_TeffAD [>] Limit flag on TeffAD
7- 10 I4 K TeffAD ? Effective temperature derived using
AMES-Dusty models (Allard et al.
2001ApJ...556..357A 2001ApJ...556..357A)
12- 14 F3.1 mag AvAD ? Absorption in V band corresponding to TeffAD
16- 19 I4 K TeffBTS Effective temperature derived using
BT-Settl models (Allard et al.
2011ASPC..448...91A 2011ASPC..448...91A)
21- 23 F3.1 mag AvBTS Absorption in V band corresponding to TeffBTS
25- 28 I4 K Teff ? Effective temperature
30 A1 --- n_Teff [ab] Note on Teff (1)
32- 34 F3.1 mag Avmean ? Absorption in V band
--------------------------------------------------------------------------------
Note (1): Note as follows:
a = Parameters derived by Comeron et al. (2009, J/A+A/500/1045);
b = Parameters derived by Comeron et al. (2013A&A...554A..86C 2013A&A...554A..86C).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 17 A17 --- ID Member of Lupus 3 identifier (1)
19- 20 I2 h RAh Hour of Right Ascension (J2000)
22- 23 I2 min RAm Minute of Right Ascension (J2000)
25- 29 F5.2 s RAs Second of Right Ascension (J2000)
31 A1 --- DE- Sign of the Declination (J2000)
32- 33 I2 deg DEd Degree of Declination (J2000)
35- 36 I2 arcmin DEm Arcminute of Declination (J2000)
38- 41 F4.1 arcsec DEs Arcsecond of Declination (J2000)
43- 46 F4.1 mag Jmag ? J-band magnitude
48- 51 F4.1 mag Ksmag ? KS-band magnitude
53 A1 --- l_SpType1 [<] Limit flag on SpType1
54- 59 A6 --- SpType1 Spectral type 1
60- 62 A3 --- r_SpType1 [acdefgh, ] Spectral type 1 reference(s) (2)
64- 67 A4 --- SpType2 Spectral type 2
68- 70 A3 --- r_SpType2 [cdfgh, ] Spectral type 2 reference(s) (2)
72- 75 A4 --- SpType3 Spectral type 3
76 A1 --- r_SpType3 [fgh] Spectral type 3 reference (2)
78- 81 A4 --- SpType4 Spectral type 4
82 A1 --- r_SpType4 [h] Spectral type 4 reference (2)
84- 87 I4 K Teff1 ? Effective temperature 1
88- 90 A3 --- r_Teff1 [acgh, ] Effective temperature 1 reference(s)
(2)
92- 95 I4 K Teff2 ? Effective temperature 2
96- 98 A3 --- r_Teff2 [bh, ] Effective temperature 2 reference(s) (2)
99-102 I4 K Teff3 ? Effective temperature 3
103 A1 --- r_Teff3 [c] Effective temperature 3 reference (2)
105-121 A17 --- Other Other name
122 A1 --- r_Other [c] Other name reference (2)
--------------------------------------------------------------------------------
Note (1): Identifiers are from:
Schwartz (1977ApJS...35..161S 1977ApJS...35..161S, Sz);
Comeron et al. (2003A&A...406.1001C 2003A&A...406.1001C, Par-Lup3);
Lopez Marti et al. (2005A&A...440..139L 2005A&A...440..139L, Lup);
Mortier et al. (2011MNRAS.418.1194M 2011MNRAS.418.1194M, M);
2MASS (Cat. II/246, J16)
this paper (SONYC-Lup3).
Note (2): Reference as follows:
a = This work;
b = Comeron et al. 2009, J/A+A/500/1045;
c = Comeron et al. 2013A&A...554A..86C 2013A&A...554A..86C;
d = Comeron et al. 2003A&A...406.1001C 2003A&A...406.1001C;
e = Allen et al. 2007ApJ...655.1095A 2007ApJ...655.1095A;
f = Hughes et al. 1994AJ....108.1071H 1994AJ....108.1071H;
g = Mortier et al. 2011MNRAS.418.1194M 2011MNRAS.418.1194M;
h = Alcala et al. 2014, J/A+A/561/A2.
--------------------------------------------------------------------------------
Global notes:
Note (G1): The IDs SONYC-Lup3-X are abbreviated with S-X.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
References:
Scholz et al. Paper I 2009ApJ...702..805S 2009ApJ...702..805S
Geers et al. Paper II 2011ApJ...726...23G 2011ApJ...726...23G
Muzic et al. Paper III 2011ApJ...732...86M 2011ApJ...732...86M
Scholz et al. Paper IV 2012ApJ...744....6S 2012ApJ...744....6S, J/ApJ/744/6
Muzic et al. Paper V 2012ApJ...744..134M 2012ApJ...744..134M, J/ApJ/744/134
Scholz et al. Paper VI 2012ApJ...756...24S 2012ApJ...756...24S
Scholz et al. Paper VII 2013ApJ...775..138S 2013ApJ...775..138S
Muzic et al. Paper IX 2015ApJ...810..159M 2015ApJ...810..159M
(End) Prepared by Tiphaine Pouvreau [CDS] 13-Jun-2017