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J/AJ/128/805   Low-mass stars in the Cepheus OB2 region  (Sicilia-Aguilar+ 2004)

Low-mass stars and accretion at the ages of planet formation in the Cepheus OB2 region. Sicilia-Aguilar A., Hartmann L.W., Briceno C., Muzerolle J., Calvet N. <Astron. J., 128, 805-821 (2004)> =2004AJ....128..805S
ADC_Keywords: Spectral types ; Equivalent widths ; Photometry, Cousins ; Photometry, infrared ; Stars, pre-main sequence Keywords: planetary systems: protoplanetary disks - stars: pre-main-sequence Abstract: We present the first identification of low-mass (spectral types K-M) stars in the young clusters Tr37 and NGC7160, members of the CepOB2 association. This is part of a program to follow the evolution of protoplanetary accretion disks through the ages thought to be crucial to understanding disk dissipation and planet formation (∼3-10Myr). Combining optical photometry and optical spectroscopy, we have identified ∼40 members in Tr37 and ∼15 in NGC7160, using several independent tests for determining the membership (optical colors, optical variability, Hα emission, and Liλ6707 absorption). Description: Our optical photometry observations of Tr37 and NGC7160 were carried on with the 1.2m telescope at the Fred Lawrence Whipple Observatory (FLWO), using the 4Shooter CCD array, between 1998 and 2002. Optical spectra of the most likely cluster members were taken in three Hydra/3.5m WIYN observing runs in 1999 January-August, 2000 November, and 2002 November. Additional spectra for the brighter candidates were observed with FAST/1.5m telescope in several remote runs from 2001 to 2003. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table2.dat 79 53 Tr 37 spectral data, extinction, and membership table3.dat 79 25 NGC 7160 spectral data, extinction, and membership table6.dat 98 53 Tr 37 photometry table7.dat 98 25 NGC 7160 photometry
Byte-by-byte Description of file: table2.dat table3.dat
Bytes Format Units Label Explanations
1- 7 A7 --- [SHB2004] Name (1) 9- 11 A3 --- ST Spectral type 17- 21 A5 --- STI Spectral interval 25- 28 I4 0.1nm EW(Ha) ? Hα absorption equivalent width 33- 35 F3.1 0.1nm EW(Li) ? Li (6707Å) absorption equivalent width 37- 38 A2 --- f_EW(Li) [? No] Flag on EW(Li) (2) 41- 44 F4.2 mag AV ? Extinction, averaged from E(V-R) and E(V-I) 49- 50 A2 --- Memb [Y PY PN] Membership (3) 57- 79 A23 --- Comm Comments (4)
Note (1): Table 2: [SHB2004] Cl* Trumpler 37 NN-NNNN in Simbad Table 3: [SHB2004] Cl* NGC 7160 NN-NNNN in Simbad Note (2): Flag on EW(Li), defined as follows: ? = probable lithium detection, although signal to noise is not good to measure EWs No = no lithium detection Note (3): The membership is defined as follows: Y = certain members PY = probable members PN = highly probable non-members that need more information to be completely ruled out Note (4): Comments use the abbreviations: Yg = stars showing an apparent younger age in the V vs. V-I diagram Ue = excess in U band IRe = near-IR excess from the 2MASS survey IRAC = objects for which we have detected IR excess from our IRAC/Spitzer images CTTS = accreting star (Classical T Tauri Star) WTTS = nonaccreting star (Weak T Tauri Star) The type of the star (accreting CTTS, nonaccreting WTTS) is based on Hα strength, IR excess, and U-band excess as accretion indicators, so then any star with Hα<10Å, and no other signatures of accretion is considered WTTS, because Hα EWs may have significant errors because of the complex background subtraction)
Byte-by-byte Description of file: table6.dat table7.dat
Bytes Format Units Label Explanations
1- 7 A7 --- [SHB2004] Name (1) 9- 10 I2 h RAh ? Hour of Right Ascension (J2000.0) 12- 13 I2 min RAm ? Minute of Right Ascension (J2000.0) 15- 19 F5.2 s RAs ? Second of Right Ascension (J2000.0) 24 A1 --- DE- Sign of Declination (J2000.0) 25- 26 I2 deg DEd ? Degree of Declination (J2000.0) 28- 29 I2 arcmin DEm ? Arcminute of Declination (J2000.0) 31- 35 F5.2 arcsec DEs ? Arcsecond of Declination (J2000.0) 41- 46 F6.3 mag Vmag ? V magnitude 49- 53 F5.3 mag V-Rc ? V-R (Cousins) colour index 57- 61 F5.3 mag V-Ic ? V-I (Cousins) colour index 65- 70 F6.3 mag Jmag ? 2MASS J magnitude 73- 78 F6.3 mag Hmag ? 2MASS H magnitude 81- 86 F6.3 mag Ksmag ? 2MASS Ks magnitude 89- 94 F6.3 mag Umag ? U magnitude 97- 98 A2 --- Var Variability (contains the bands where variations were detected)
Note (1): Table6: [SHB2004] Cl* Trumpler 37 NN-NNNN in Simbad Table7: [SHB2004] Cl* NGC 7160 NN-NNNN in Simbad
History: From electronic version of the journal
(End) Marianne Brouty [CDS] 31-Mar-2005
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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