J/ApJS/185/451 PMS stars in the Cepheus flare region (Kun+, 2009)
Pre-main-sequence stars in the Cepheus flare region.
Kun M., Balog Z., Kenyon S.J., Mamajek E.E., Gutermuth R.A.
<Astrophys. J. Suppl. Ser., 185, 451-476 (2009)>
=2009ApJS..185..451K 2009ApJS..185..451K
ADC_Keywords: YSOs ; Photometry, UBVRI ; Spectroscopy ; Stars, ages ;
Stars, masses ; Accretion ; Diffuse clouds
Keywords: ISM: clouds - ISM: individual (Cepheus flare) - stars: formation
stars: pre-main sequence
Abstract:
We present results of optical spectroscopic and BVRCIC photometric
observations of 77 pre-main-sequence (PMS) stars in the Cepheus flare
region. A total of 64 of these are newly confirmed PMS stars,
originally selected from various published candidate lists. We
estimate effective temperatures and luminosities for the PMS stars,
and comparing the results with PMS evolutionary models, we estimate
stellar masses of 0.2-2.4M☉ and stellar ages of 0.1-15Myr. Among
the PMS stars, we identify 15 visual binaries with separations of
2-10". From archival IRAS, Two Micron All Sky Survey, and Spitzer
data, we construct their spectral energy distributions (SEDs) and
classify 5% of the stars as Class I, 10% as Flat SED, 60% as Class II,
and 3% as Class III young stellar objects. We identify 12 classical
T Tauri stars and two weak-line T Tauri stars as members of NGC 7023,
with a mean age of 1.6Myr. The 13 PMS stars associated with L1228
belong to three small aggregates: RNO 129, L1228A, and L1228S. The age
distribution of the 17 PMS stars associated with L1251 suggests that
star formation has propagated with the expansion of the Cepheus flare
shell. We detect sparse aggregates of ∼6-7Myr old PMS stars around the
dark clouds L1177 and L1219, at a distance of ∼400pc. Three T Tauri
stars appear to be associated with the Herbig Ae star SV Cep at a
distance of 600pc. Our results confirm that the molecular complex in
the Cepheus flare region contains clouds of various distances and
star-forming histories.
Description:
Spectra of 155 stars were observed using the CAFOS instrument on the
2.2m telescope of Calar Alto Observatory between 1999 August 7-11,
2004 August 10-15, 2005 September 11-14, and 2008 August 26-31. With
the help of the FLWO staff (P. Berlind, M. Calkins) we acquired
low-resolution optical spectra of 46 target stars with FAST, a high
throughput slit spectrograph mounted on the Fred L. Whipple
Observatory 1.5m telescope on Mount Hopkins, Arizona.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 154 77 List of observed PMS stars and associated clouds
table2.dat 82 98 List of the observed stars rejected as PMS stars
table5.dat 87 85 Photometric data of the observed stars
table7.dat 96 76 Parameters of observed stars, derived from our
optical data
refs.dat 44 19 References in table 1
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See also:
J/A+A/272/235 : Stars in the dark cloud L1251 (Kun+ 1993)
J/ApJS/115/59 : Cepheus flare molecular clouds (Kun, 1998)
J/ApJS/184/18 : Young stellar clusters Spitzer survey (Gutermuth+, 2009)
J/ApJS/185/198 : The Cepheus flare observed with IRAC and MIPS (Kirk+, 2009)
J/BaltA/18/33 : Photometry of stars around NGC 7023 (Zdanavicius+, 2009)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 30 A30 --- Name Star name
32- 83 A52 --- ONames Other name(s)
85 A1 --- f_Name [bc] Binarity reported (1)
86- 96 A11 --- IRAS IRAS identification (HHMMs+DDMM with or
without F at the beginning)
98-113 A16 --- 2MASS 2MASS identification (HHMMSSss+DDMMSSs)
115-117 I3 --- Spitz ?=- Spitzer id. (2)
118 A1 --- n_Spitz [?n] Flag on Spitzer id. (2)
120-127 A8 --- Cloud ?=--- Name of the associated cloud
129-145 A17 --- CType Candidate type (CTTS, Hα, IRAS, etc.)
147-154 A8 --- Ref Reference(s) in refs.dat file
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Note (1): Flag as follows:
b = Binarity of the star embedded in RNO 129 was reported by Magakian et al.
(2004Ap.....47..519M 2004Ap.....47..519M). Our observations have shown that both components
are PMS stars.
c = Binarity of NGC 7023 RS2 and LkHα 428 was reported by Rosino and
Romano (1962CoAsi.125....1R 1962CoAsi.125....1R). Our observations have shown that both
components of these doubles are PMS stars.
Note (2): The "Spit" column shows the identifier of the stars observed by
Spitzer: if column "n_Spit" is "n" by Gutermuth et al. (2009, Cat.
J/ApJS/184/18; NGC 7129), and in Kirk et al. (2009, Cat.
J/ApJS/185/198; other stars). The question mark (?) in "n_Spit"
means that the identification is uncertain.
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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 --- Name Source name
23- 38 A16 --- 2MASS 2MASS identification
40- 49 A10 --- Inst Instrument used in observation
51- 80 A30 --- Comm Comment
82 A1 --- Ref Reference (1)
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Note (1): Reference as follows:
1 = Veron-Cetty and Veron (2006, Cat. VII/248, obsolated by VII/258);
2 = Schaefer (1986ApJ...307..644S 1986ApJ...307..644S).
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- Name Star name
31 A1 --- m_Name [ABW] Component
33- 38 F6.3 mag Bmag ?=- Johnson B-band magnitude (1)
40- 43 F4.2 mag e_Bmag ?=- Uncertainty in Bmag (2)
45- 49 F5.2 mag Vmag ?=- Johnson V-band magnitude (1)
51- 54 F4.2 mag e_Vmag ?=- Uncertainty in Vmag (2)
56- 61 F6.3 mag Rcmag ?=- Cousins R-band magnitude (1)
63- 66 F4.2 mag e_Rcmag ? Uncertainty in Rcmag (2)
68- 73 F6.3 mag Icmag Cousins I-band magnitude (1)
75- 78 F4.2 mag e_Icmag ?=- Uncertainty in Icmag (2)
80- 98 A19 --- Comm Comment (variability)
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Note (1): The magnitudes listed are averages of two to four independent
measurements.
Note (2): Mean absolute deviation of the derived magnitudes.
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Byte-by-byte Description of file: table7.dat
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Bytes Format Units Label Explanations
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1- 32 A32 --- Cloud Associated clouds name
34- 49 A16 --- Name Star name
51- 54 F4.2 mag AV Visual extinction AV derived from the
color excesses
56- 60 F5.2 Lsun Lbol Bolometric luminosity of the star
62- 65 I4 K Teff Effective temperature derived from the
spectral classification
67- 70 F4.2 Msun Mass ?=- Star mass derived from HR diagrams
72- 75 F4.1 Myr Age ?=- Age of the star derived from the HRD
76 A1 --- u_Age [:] Uncertainty flag on Age
78- 83 F6.2 [Msun/yr] log(Md)1 ?=- Log of accretion rate from disk1 (1)
85- 90 F6.2 [Msun/yr] log(Md)2 ?=- Log of accretion rate from disk2 (1)
92- 96 F5.2 [Msun/yr] log(Md)3 ?=- Log of accretion rate from disk3 (1)
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Note (1): Logarithm of accretion rates from the disk (log(dM/dt))
in M☉/yr as:
1 = derived from the 10% width of the Hα line (Natta et al.,
2004A&A...424..603N 2004A&A...424..603N),
2 = from the luminosity of Hα emission line,
3 = from the CaIIλ8542 line (Dahm, 2008AJ....136..521D 2008AJ....136..521D).
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Ref Reference number
4- 22 A19 --- BibCode Bibcode
24- 44 A21 --- Aut Author's name
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History:
* 22-Mar-2010: From electronic version of the journal
* 02-Jun-2010: Corrected names in tables 1, 5, 7 to ensure identical
names for identical stars.
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 22-Mar-2010