J/ApJ/724/835 The Spitzer c2d survey of WTTSs. III. (Wahhaj+, 2010)
The Spitzer c2d survey of weak-line T Tauri stars.
III. The transition from primordial disks to debris disks.
Wahhaj Z., Cieza L., Koerner D.W., Stapelfeldt K.R., Padgett D.L., Case A.,
Keller J.R., Merin B., Evans N.J., Harvey P., Sargent A.,
van Dishoeck E.F., Allen L., Blake G., Brooke T., Chapman N., Mundy L.,
Myers P.C.
<Astrophys. J., 724, 835-854 (2010)>
=2010ApJ...724..835W 2010ApJ...724..835W
ADC_Keywords: Photometry, infrared ; Stars, pre-main sequence ; YSOs ;
Equivalent widths ; Binaries, spectroscopic ; Molecular clouds
Keywords: infrared: stars - planetary systems - protoplanetary disks -
stars: pre-main sequence
Abstract:
We present 3.6 to 70um Spitzer photometry of 154 weak-line T Tauri
stars (WTTSs) in the Chamaeleon, Lupus, Ophiuchus, and Taurus star
formation regions, all of which are within 200pc of the Sun. For a
comparative study, we also include 33 classical T Tauri stars which
are located in the same star-forming regions. Spitzer sensitivities
allow us to robustly detect the photosphere in the IRAC bands (3.6 to
8um) and the 24um MIPS band. In the 70um MIPS band, we are able to
detect dust emission brighter than roughly 40 times the photosphere.
These observations represent the most sensitive WTTSs survey in the
mid- to far-infrared to date and reveal the frequency of outer disks
(r=3-50AU) around WTTSs. The 70um photometry for half the c2d WTTSs
sample (the on-cloud objects), which were not included in the earlier
papers in this series, those of Padgett et al. (2006ApJ...645.1283P 2006ApJ...645.1283P)
and Cieza et al. (2007, Cat. J/ApJ/667/308) are presented here for the
first time.
Description:
In the 50 Spitzer/IRAC and MIPS hours allotted to this program (PID,
173) we observed 154 WTTS objects and 33 CTTS, from 2004 May to 2005
Mars. The details of the sample and observing parameters are
well-described in Padgett et al. (2006ApJ...645.1283P 2006ApJ...645.1283P).
We had available reduced high-resolution optical spectra (KPNO 4m,
Echelle Spectra, R∼42000; Keller et al. 2003AAS...203.0502K 2003AAS...203.0502K, Keller
(2004, MS thesis, Northern Arizona Univ.)) for 161 of our 187 targets.
From these, we were able to measure the FW.1H(Hα) to a precision
of roughly 30km/s.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 118 186 Stellar properties
table2.dat 110 186 2MASS and Spitzer photometry
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
J/ApJS/196/4 : New young star candidates in Taurus-Auriga (Rebull+, 2011)
J/ApJ/712/925 : Transition circumstellar disks in Ophiuchus (Cieza+, 2010)
J/A+A/519/A83 : T Tau stars toward the Taurus-Auriga region (Takita+ 2010)
J/ApJ/703/1964 : Spectra of three nearby star-forming regions (Furlan+, 2009)
J/ApJS/181/321 : Properties of Spitzer c2d dark clouds (Evans+, 2009)
J/PASJ/60/209 : Faint companions around YSOs in TMC (Itoh+, 2008)
J/ApJ/676/427 : MIPS and IRAC data on ChaII PMS stars (Alcala+, 2008)
J/ApJS/177/551 : Spitzer c2d survey of Lupus dark clouds (Merin+, 2008)
J/ApJS/179/249 : Low-luminosity embedded protostar population (Dunham+, 2008)
J/ApJ/675/1375 : IRAC/MIPS photometry in Cha I (Luhman+, 2008)
J/A+A/485/155 : HK photometry of rho Oph PMS stars (Alves de Oliveira+, 2008)
J/ApJ/667/308 : Weak-line T Tauri in Spitzer c2d Survey. II. (Cieza+, 2007)
J/ApJS/173/104 : Stellar population in Chamaeleon I (Luhman, 2007)
J/ApJ/658/480 : Pre-main-sequence stars in Lupus association (Makarov+, 2007)
J/ApJ/646/297 : Spitzer observations of PMS stars (Rebull+, 2006)
J/A+A/452/245 : Near-IR photometry of PMS stars in rho Oph (Natta+, 2006)
J/ApJ/581/1194 : Taurus-Auriga PMS stars ages and Teff (Palla+, 2002)
J/A+AS/132/173 : New weak-line T Tauri stars in Taurus-Auriga (Li+ 1998)
J/A+AS/124/449 : Young stars south of Taurus-Auriga (Magazzu+ 1997)
J/A+AS/123/329 : New weak-line T Tauri stars in Lupus (Krautter+ 1997)
J/A+A/319/184 : New WTTS in the Chamaeleon complex (Alcala+ 1997)
J/A+A/326/211 : T Tau Stars (Wichmann+, 1997)
J/A+A/312/439 : New T Tauri stars in Taurus-Auriga (Wichmann+, 1996)
J/ApJS/101/117 : UBVRIJHKLMNQ photometry in Taurus-Auriga (Kenyon+ 1995)
http://irsa.ipac.caltech.edu/data/SPITZER/C2D/ : c2d Spitzer data home page
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 21 A21 --- ID Star identification
23- 27 A5 --- Type [WTTSs/CTTSs] TTauri type: Weak or Classical
29- 34 F6.2 0.1nm EW.Ha Hα equivalent width
36- 39 I4 km/s FW1Ha ? Full width at 10% of Hα line height (1)
41- 48 A8 --- SpT MK spectral type
50- 54 A5 --- SEDt SED type (RJ, TNIR, TIRAC, or T24) (2)
56 A1 --- l_sep Limit flag on sep (3)
57- 62 F6.3 arcsec sep ? Separation of binary component (3)
64- 67 I4 d Per ? Period of binary component
69- 71 A3 --- Bin [SB /nSB] Spectroscopic binarity (nSB = not SB)
73- 75 A3 --- r_Bin Binary indication reference(s) (4)
77- 81 I5 K Teff Effective temperature
83- 89 F7.2 Lsun L* Stellar luminosity
91- 98 E8.2 yr Age Estimated Age
100-103 F4.1 mag Av Extinction (5)
105-108 F4.1 deg Dedge Distance from cloud edge (6)
110 A1 --- l_Ld/L* Limit flag on Ld/L*
111-118 E8.2 --- Ld/L* Fractional luminosity of the disk (Ldisk/L*)
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Note (1): "0" indicates non detections. Negative velocities indicate absorption.
Note (2): We designate objects according to their disk "turn-on" wavelengths of
SEDs. Thus, we have:
* 7 T24 (turns on at 24um) objects,
* 5 TIRAC objects (turns on at IRAC wavelengths),
* 4 TNIR objects (already show excess at IRAC1 (3.6um) and could
have K band excess).
* RJ indicates diskless objects.
Note (3): Limits on non detection are also given; e.g., <0.13 indicates a
companion is only possible for ρ<0.13".
Note (4): References as follows:
1 = Leinert et al. 1993A&A...278..129L 1993A&A...278..129L,
2 = Simon et al. 1995ApJ...443..625S 1995ApJ...443..625S,
3 = Lafreniere et al. 2008ApJ...683..844L 2008ApJ...683..844L,
4 = Prato 2007ApJ...657..338P 2007ApJ...657..338P,
5 = Ratzka et al. 2005A&A...437..611R 2005A&A...437..611R,
6 = Kohler R. 2001AJ....122.3325K 2001AJ....122.3325K,
7 = Guenther et al. 2007A&A...467.1147G 2007A&A...467.1147G,
8 = Kohler & Leinert 1998A&A...331..977K 1998A&A...331..977K,
9 = Sartoretti et al. 1998A&A...334..592S 1998A&A...334..592S,
10 = Steffen et al. 2001AJ....122..997S 2001AJ....122..997S,
11 = Melo C.H.F. 2003A&A...410..269M 2003A&A...410..269M,
12 = Ghez et al. 1997ApJ...481..378G 1997ApJ...481..378G,
13 = Barsony et al. 2003ApJ...591.1064B 2003ApJ...591.1064B
Note (5): We use AV=5.88E(J-K) to estimate the extinction for our sources,
where E(J-K) is the excess in J-K color with respect to the expected
stellar photosphere. The main-sequence J-K colors are from Kenyon &
Hartmann (1995, Cat. J/ApJS/101/117).
Note (6): Negative numbers indicate that objects are within cloud boundary as
defined in the text.
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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- 21 A21 --- ID Star identification
23- 24 I2 h RAh Hour of right ascension (J2000)
26- 27 I2 min RAm Minute of right ascension (J2000)
29- 32 F4.1 s RAs Second of right ascension (J2000)
34 A1 --- DE- Sign of declination (J2000)
35- 36 I2 deg DEd Degree of declination (J2000)
38- 39 I2 arcmin DEm Arcminute of declination (J2000)
41- 44 F4.1 arcsec DEs Arcsecond of declination (J2000)
46- 51 F6.1 mJy FJ 2MASS J-band flux density
53- 58 F6.1 mJy FH 2MASS H-band flux density
60- 65 F6.1 mJy FKs 2MASS Ks-band flux density
67- 72 F6.1 mJy F3.6 Spitzer/IRAC 3.6um-band flux density (7)
74- 79 F6.1 mJy F4.5 ? Spitzer/IRAC 4.5um-band flux density (7)
81- 86 F6.1 mJy F5.8 ? Spitzer/IRAC 5.8um-band flux density (7)
88- 93 F6.1 mJy F8.0 ? Spitzer/IRAC 8.0um-band flux density (7)
95-100 F6.1 mJy F24 Spitzer/MIPS 24um-band flux density (7)
102 A1 --- l_F70 Limit flag on F70
103-106 I4 mJy F70 ? Spitzer/MIPS 70um-band flux density
108-110 I3 mJy e_F70 ? F70 uncertainty
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Note (7): The absolute calibration uncertainties in the IRAC bands and the
MIPS-24um band are 5% and 10%, respectively. These calibration
uncertainties are typically more than twice the random errors and thus
dominate the total photometric uncertainty.
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History:
From electronic version of the journal
References:
Padgett et al. Paper I. 2006ApJ...645.1283P 2006ApJ...645.1283P
Cieza et al. Paper II. 2007ApJ...667..308C 2007ApJ...667..308C Cat. J/ApJ/667/308
(End) Emmanuelle Perret [CDS] 01-Aug-2012