J/AJ/132/2135 High-resolution spectroscopy in Tr 37 (Sicilia-Aguilar+, 2006)
High-resolution spectroscopy in Tr 37:
gas accretion evolution in evolved dusty disks.
Sicilia-Aguilar A., Hartmann L.W., Furesz G., Henning T., Dullemond C.,
Brandner W.
<Astron. J., 132, 2135-2155 (2006)>
=2006AJ....132.2135S 2006AJ....132.2135S
ADC_Keywords: Associations, stellar ; Equivalent widths ; Rotational velocities
Keywords: accretion, accretion disks - line: profiles -
planetary systems: protoplanetary disks - stars: pre-main sequence -
stars: rotation
Abstract:
Using the Hectochelle multifiber spectrograph, we have obtained
high-resolution (R∼34000) spectra in the Hα region for a large
number of stars in the 4Myr old cluster Tr 37, containing 146
previously known members and 26 newly identified ones. We present the
Hα line profiles of all members, compare them to our IR
observations of dusty disks (Two Micron All Sky Survey JHK + IRAC +
MIPS 24um), use the radial velocities as a membership criterion, and
calculate the rotational velocities.
Description:
Hectochelle is the high-resolution, multifiber echelle spectrograph,
which operates at the wide-field mode of the Cassegrain 6.5m MMT
telescope in Mount Hopkins, Arizona.
We observed two fields in Tr 37 during two engineering runs on 2004
December 1 and 2. A total of 231 and 233 objects, respectively, were
observed in the configurations.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 103 183 Spectral Information
table2.dat 85 170 Summary of disk and stellar properties of
members and probable members
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See also:
J/AJ/128/805 : Low-mass stars in Cepheus OB2 region (Sicilia-Aguilar+, 2004)
J/AJ/130/188 : Young stars in Tr 37 and NGC 7160 (Sicilia-Aguilar+, 2005)
J/ApJ/638/897 : IR photometry in Tr 37 and NGC 7160 (Sicilia-Aguilar+, 2006)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- [SHB2004] Identification (NN-NNNN), if exist (G1)
9- 24 A16 --- 2MASS The 2MASS identification (HHMMSSss+DDMMSSs)
26- 33 A8 --- SpType MK spectral type
35- 37 I3 0.1nm EWHa1 ? Hi-res equivalent width of Hα, in Å
38 A1 --- u_EWHa1 Uncertainty flag in EW-hi
40- 43 I4 0.1nm EWHa2 ? Low-res equivalent width of Hα, in Å
45- 47 F3.1 0.1nm EWLi ? Equivalent width of Li (6707), in Å
48 A1 --- u_EWLi Uncertainty flag in EW-Li
50- 54 A5 --- Type Hα type (2)
56- 58 I3 km/s FWHa ? Hα full width measured at 10% intensity
60- 63 F4.1 --- R ? Goodness of the cross-correlation
64 A1 --- u_R Uncertainty flag in R
66- 71 F6.1 km/s cz ? Radial velocity
73- 75 F3.1 km/s e_cz ? Uncertainty in cz
76 A1 --- u_cz Uncertainty flag in cz
78- 81 F4.1 km/s vsini ? Rotational velocity (vsin(i)) (3)
82 A1 --- u_vsini Uncertainty in Vsini
84-103 A20 --- Com Comment(s) (4)
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Note (2): Hα type is a combination of c, c: (c), w, w: and (w) meaning:
c = (standing for CTTS) if broad emission with extended velocity
wings was detected
w = (standing for WTTS) otherwise
Note (3): The error in the rotational velocity is proportional to the
rotational velocity times 1/(1+R).
Note (4): Membership is stated with the abbreviations:
Y = sure member
P = probable member
PN = probable non-member
N = non-member
(e) = membership was obtained from the presence of Hα strong
emission and/or Li absorption lines
(r) = membership was obtained via the radial velocity (r)
* = new members
conf = denotes previous possible members (from low-resolution
spectroscopy) that are confirmed as members based on the
radial velocities
rej = denotes previous possible members that are most likely
non-members according to radial velocities.
Finally, a comment on binarity (SB2 or SB1) is added in this field.
TOn = nonaccreting transition object TOa = accreting transition object
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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- 7 A7 --- [SHB2004] Identification (NN-NNNN),
if exist (G1) (1)
9- 24 A16 --- 2MASS 2MASS identification (HHMMSSss+DDMMSSs)
26- 34 A9 --- SpType MK spectral type
36- 45 F10.1 Myr Age ? Age (2)
47- 49 F3.1 solMass Mass ? Stellar mass (2)
51- 54 F4.1 km/s vsini ? Rotational velocity (vsin(i))
56- 58 F3.1 km/s e_vsini ? Uncertainty in vsini (3)
59 A1 --- u_vsini Uncertainty flag in vsini
61- 70 A10 10-8solMass/yr dM/dt ? Accretion rate (4)
72- 85 A14 --- Com Class and comments (5)
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Note (1): Summary of the properties of the stars in Tr 37. Only the star
being sure or probable members are displayed here.
Note (2): Ages and masses are derived from the V vs. V-I diagram, using the
isochrones by Siess et al. 2000A&A...358..593S 2000A&A...358..593S (see Paper I, Paper II
(2004AJ....128..805S 2004AJ....128..805S, 2005AJ....130..188S 2005AJ....130..188S) for a detailed description
of spectral typing and age/mass calculation).
Note (3): Errors in the vsini are derived as vsini/(1+R) (see Tonry & Davis
1979AJ.....84.1511T 1979AJ.....84.1511T; Hartmann et al., 1986ApJ...309..275H 1986ApJ...309..275H).
Note (4): The best estimate of the accretion rate is selected for this
summary. Whenever accretion rates derived from U band photometry were
available (Paper II), we included them. Since some stars had been
observed in U band in two campaigns, we include both values. As in the
text, we denote with dM/dt=0 those stars with no U excess and Hα
profiles consistent with diskless WTTS or Class III objects. For stars
with no detectable U excess but broad profiles, we give an upper limit
to accretion of <0.1 10-8M☉/yr (see text). We do not provide
an accretion value for stars not observed in U band and broad or
probably broad Hα profiles. For the exceptional star 13-277,
whose spectral type is uncertain due to veiling, we provide an
approximate accretion rate from the Hα width at 10% maximum (see
text). Most of these stars without a value for accretion are likely to
be accreting (showing broad profiles, see figures).
Note (5): The comments include the class (I, II, III or Transition object),
the binarity as:
SB1 = single-lined spectroscopic binary;
SB2 = double-lined spectroscopic binary
and the details on the Hα profile:
Ba = blue-shifted absorption; Ra= red-shifted absorption;
Za = absorption with approximately zero velocity shift;
B = blue-shifted emission; R=red-shifted emission;
IPC = inverse P-Cygni profile.
Uncertain values are denoted by " : " .
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Global notes:
Note (G1): [SHB2004] Trumpler 37 NN-NNNN in Simbad
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History:
From electronic version of the journal
References:
Sicilia-Aguilar et al., Paper I 2004AJ....128..805S 2004AJ....128..805S, Cat. J/AJ/128/805
Sicilia-Aguilar et al., Paper II 2005AJ....130..188S 2005AJ....130..188S, Cat. J/AJ/130/188
Sicilia-Aguilar et al., Paper III 2006ApJ...638..897S 2006ApJ...638..897S, Cat. J/ApJ/638/897
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 24-Jul-2008