J/A+A/547/A80 Properties of Collinder 69 low-mass members (Bayo+, 2012)
Spectroscopy of very low-mass stars and brown dwarfs in the Lambda Orionis
star-forming region. II. Rotation, activity and other properties of
spectroscopically confirmed members of Collinder 69.
Bayo A., Barrado D., Huelamo N., Morales-Calderon M., Melo C., Stauffer J.,
Stelzer B.
<Astron. Astrophys., 547, A80-80 (2012)>
=2012A&A...547A..80B 2012A&A...547A..80B
ADC_Keywords: Clusters, open ; Stars, early-type ; Equivalent widths
Keywords: accretion, accretion disks - stars: pre-main sequence -
stars: variables: T Tauri, Herbig Ae/Be - brown dwarfs -
circumstellar matter - stars: low-mass
Abstract:
Most observational studies conducted so far point toward brown dwarfs
sharing a similar formation mechanism as the one that is accepted for
low-mass stars. However, larger databases and more systematic studies
are needed before strong conclusions can be reached.
In this second paper of a series devoted to studying the spectroscopic
properties of the Lambda Orionis star-forming region members, we study
accretion, activity and rotation for a wide set of spectroscopically
confirmed members of the central star cluster Collinder 69 to assess
analogies and/or differences between the brown-dwarf and stellar
populations of this cluster. Moreover, we present comparisons with
other star-forming regions of similar and different ages to address
environmental effects on our conclusions.
We studied prominent photospheric lines to derive rotational
velocities and emission lines to distinguish between accretion
processes and chromospheric activity. In addition, we include
information about disk presence and X-ray emission.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table6.dat 160 193 Parameters and measurements obtained in this
work for Collinder 69 confirmed members and
comparison with previous studies
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See also:
J/AJ/118/2409 : VRI photometry of lambda Ori PMS stars (Dolan+, 1999)
J/AJ/121/2124 : lambda Ori pre-main-sequence stars photometry (Dolan+, 2001)
J/ApJ/610/1064 : lambda Ori substellar population (Barrado y Navascues+ 2004)
J/ApJ/664/481 : Collinder 69 opt/IR photometry (Barrado y Navascues+ 2007)
J/A+A/488/167 : Low-mass stars in sigma Ori and lambda Ori (Sacco+, 2008)
J/A+A/492/277 : Analysis of Collinder 69 stars with VOSA (Bayo+, 2008)
J/MNRAS/385/2210 : Spectroscopy around lam Ori and sig Ori (Maxted+, 2008)
J/A+A/526/A21 : Collinder 69 X-ray sources (Barrado+, 2011)
J/A+A/536/A63 : Collinder 69 very low mass stars & brown dwarfs (Bayo+ 2011)
Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Name Object name
13- 15 A3 --- Bin Spectroscopic binarity (SB, SB1 or SB2)
17- 23 A7 --- r_Bin Rerefence for Bin (1)
25- 27 A3 --- Class Infrared class, II or III (2)
29- 39 A11 --- Type Disk type
40 A1 --- l_vsini Limit flag on vsini
41- 44 F4.1 km/s vsini ? Rotational velocity
46- 49 F4.1 km/s E_vsini ? Error on vsini (upper value)
51- 53 F3.1 km/s e_vsini ? Error on vsini (lower value)
54 A1 --- f_visin2 [,-] "," for 2nd value or "-" for a range
55 A1 --- l_vsini2 Limit flag on vsini2
56- 58 I3 km/s vsini2 ? Second value for vsini
59 A1 --- r_vsini2 [*] Origin of vsini, *=this work (3)
61- 62 A2 --- Acc [YN? ] Accretor flag (4)
64- 69 F6.2 [Msun/yr] lg(dMacc) ? Mass accretion rate, log(dMass/dt)
71- 74 F4.2 [Msun/yr] e_lg(dMacc) ? rms uncertainty on lg(dMacc)
75 A1 --- r_lg(dMacc) [a] Reference for Macc (5)
76 A1 --- --- [,]
77- 81 F5.1 [Msun/yr] lg(dMacc)2 ? Second value for Mass accretion rate
83- 85 F3.1 [Msun/yr] e_lg(dMacc)2 ? rms uncertainty on lg(dMacc)2
86 A1 --- r_lg(dMacc)2 [c] Reference for lg(Macc)2 (5)
88- 94 F7.2 0.1nm W(Ha) ? Hα 6563Å equivalent width
96-100 F5.2 0.1nm e_W(Ha) ? rms uncertainty on W(Ha)
101 A1 --- r_W(Ha) [abc] Reference for W(Ha) (5)
102 A1 --- --- [,]
103-108 F6.2 0.1nm W(Ha)2 ? Second value for Hα 6563Å
equivalent width
110-113 F4.2 0.1nm e_W(Ha)2 ? rms uncertainty on W(Ha)2
114 A1 --- r_W(Ha)2 [bc] Reference for W(Ha)2 (5)
115 A1 --- --- [,]
116-120 F5.2 0.1nm W(Ha)3 ? Third value for Hα 6563Å
equivalent width
122-125 F4.2 0.1nm e_W(Ha)3 ? rms uncertainty on W(Ha)3
126 A1 --- r_W(Ha)3 [c] Reference for W(Ha)3 (5)
128-130 I3 km/s W10(Ha) ? Hα 6563Å Full Width at
10% of the flux
132-133 I2 km/s e_W10(Ha) ? rms uncertainty on W10(Ha)
134 A1 --- r_W10(Ha) [ac] Reference for W10(Ha) (5)
135 A1 --- --- [,]
137-139 I3 km/s W10(Ha)2 ? Second value of Hα 6563Å
Full Width at 10% of the flux
141-142 I2 km/s e_W10(Ha)2 ? rms uncertainty on W10(Ha)2
143 A1 --- r_W10(Ha)2 [c] Reference for W10(Ha)2 (5)
144-148 F5.2 0.1nm W(CaII)1 ? CaII (8498Å) equivalent width
149 A1 --- --- [;]
150-154 F5.2 0.1nm W(CaII)2 ? CaII (8542Å) equivalent width
155 A1 --- --- [;]
156-160 F5.2 0.1nm W(CaII)3 ? CaII (8662Å) equivalent width
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Note (1): Binary reference as follows:
S08 = Sacco et al. (2008, Cat. J/A+A/488/167)
M08 = Maxted et al. (2008, Cat. J/MNRAS/385/2210)
Note (2): Infrared Class derived with the IRAC data in Barrado y Navascues et
al. (2007, Cat. J/ApJ/664/481) or Morales-Calderon (2008,
Ph.D. Thesis, Universidad Autonoma de Madrid).
Note (3): From Sacco et al. (2008, Cat. J/A+A/488/167) or this work (*).
Note (4): According to Hα EW and Barrado y Navascues & Martin
(2003AJ....126.2997B 2003AJ....126.2997B) criterion after the analysis of the presence of disk.
Note (5): Measurement from the following references:
a = This work
b = Dolan & Mathieu (1999, Cat. J/AJ/118/2409; 2001, Cat. J/AJ/121/2124)
c = Sacco et al. (2008, Cat. J/A+A/488/167)
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History:
From electronic version of the journal
References:
Bayo et al., Paper I 2011A&A...536A..63B 2011A&A...536A..63B, J/A+A/536/A63
(End) Patricia Vannier [CDS] 28-Jan-2013