J/ApJ/822/79 YSOs search in LDN 1340 in optical (Kun+, 2016)
The intermediate-mass star-forming region Lynds 1340. An optical view.
Kun M., Moor A., Szegedi-Elek E., Reipurth B.
<Astrophys. J., 822, 79-79 (2016)>
=2016ApJ...822...79K 2016ApJ...822...79K (SIMBAD/NED BibCode)
ADC_Keywords: YSOs ; Photometry, UBVRI ; Photometry, infrared ; Spectroscopy ;
Spectral types ; Stars, masses ; Equivalent widths
Keywords: ISM: clouds; ISM: individual: L1340; stars: formation;
stars: pre-main sequence; stars: variables: T Tauri, Herbig Ae/Be
Abstract:
We have performed an optical spectroscopic and photometric search for
young stellar objects associated with the molecular cloud Lynds 1340,
and examined the structure of the cloud by constructing an extinction
map, based on SDSS data. The new extinction map suggests a shallow,
strongly fragmented cloud, having a mass of some 3700M☉.
Longslit spectroscopic observations of the brightest stars over the
area of L1340 revealed that the most massive star associated with
L1340 is a B4-type, ∼5M☉ star. The new spectroscopic and
photometric data of the intermediate-mass members led to a revised
distance of 825-80+110pc, and revealed seven members of the young
stellar population with M≳2M☉. Our search for Hα emission
line stars, conducted with the Wide Field Grism Spectrograph 2 on the
2.2m telescope of the University of Hawaii and covering a 30'x40'
area, resulted in the detection of 75 candidate low-mass pre-main
sequence stars, 58 of which are new. We constructed spectral energy
distributions (SEDs) of our target stars, based on SDSS, 2MASS,
Spitzer, and WISE photometric data, derived their spectral types,
extinctions, and luminosities from BVRIJ fluxes, estimated masses by
means of pre-main sequence evolutionary models, and examined the disk
properties utilizing the 2-24µm interval of the SED. We measured
the equivalent width of the Hα lines and derived accretion
rates. The optically selected sample of pre-main sequence stars has a
median effective temperature of 3970K, a stellar mass of 0.7M☉,
and an accretion rate of 7.6x10-9M☉/yr.
Description:
We observed the optical spectra of 23 stars, utilizing several
instruments, namely CAFOS with the G-100 grism, installed on the 2.2m
telescope of the Calar Alto Observatory, FAST on the 1.5m telescope of
the Fred Lawrence Whipple Observatory, ALFOSC with grism 8 on the
Nordic Optical Telescope in the Observatorio del Roque de los
Muchachos in La Palma, and the low-resolution slit spectrograph
operated on the 1m RCC telescope of the Konkoly Observatory between
1999 Aug 07 and 2011 Sep 27 (see table 1).
We observed L1340 with the Wide Field Grism Spectrograph 2 (WFGS2),
installed on the University of Hawaii 2.2m telescope, on 2011 January
1, October 15, 16, and 18, and 2012 August 10. We covered an area of
30x40arcmin, centered on RA=2:30,DE=72:48(J2000), with a mosaic of 12
overlapping fields. We found 75 stars with Hα emission by
examining the images visually. See section 2.2 and table 2.
Spitzer L1340 was observed by the Spitzer Space Telescope using
Spitzer's Infrared Array Camera (IRAC) on 2009 March 16 and by the
Multiband Imaging Photometer for Spitzer (MIPS) on 2008 November 26
(Prog. ID: 50691, PI: G. Fazio). A small part of the cloud, centered
on RNO 7, was observed in the four IRAC bands on 2006 September 24
(Prog. ID: 30734, PI: D. Figer).
All but eight of the Hα sources have counterparts in the AllWISE
Source Catalog (Wright et al. 2010AJ....140.1868W 2010AJ....140.1868W; see II/328).
L1340 is situated within Stripe 1260 of the SEGUE survey (Yanny et al.
2009, J/AJ/137/4377). Each of our target stars has a counterpart in
the SDSS Data Release 9 (Ahn et al. 2012, V/139) within 1" of the
2MASS position.
Objects:
----------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------
02 30 40 +72 57.3 L1340 = LDN 1340
----------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 83 29 Log of spectroscopic observations of 23
young star candidates
table2.dat 84 75 Coordinates, Hα equivalent widths, and
cross-identifiers of the Hα emission stars
table3.dat 70 11 Results for the B, A, and F type stars associated
with L1340
table4.dat 48 14 Spectral types and Hα equivalent widths of
the T Tauri type targets of our longslit
observations
table6.dat 86 77 Properties of the Hα emission stars derived
from the photometric and EW(Hα) data
table9.dat 251 86 *UBVRcIcJHKs, Spitzer and AllWISE magnitudes
of the optically selected candidate YSOs of L1340
(tables 9 and 10)
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Note on table9.dat: We transformed the SDSS ugriz magnitudes into the
Johnson-Cousins UBVRcIc system, using the equations given in
Ivezic+ (2007ASPC..364..165I 2007ASPC..364..165I, for BVRcIc) and Jordi+ (2006A&A...460..339J 2006A&A...460..339J,
for U). See section 2.3 for further explanations.
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See also:
V/139 : The SDSS Photometric Catalog, Release 9 (Adelman-McCarthy+, 2012)
II/297 : AKARI/IRC mid-IR all-sky Survey (ISAS/JAXA, 2010)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
J/ApJS/224/22 : The YSO population of LDN 1340 in infrared (Kun+, 2016)
J/AJ/149/200 : VRI photometry in NGC 7129 (Dahm+, 2015)
J/ApJ/795/L26 : Candidate eruptive young stars in Lynds 1340 (Kun+, 2014)
J/MNRAS/435/3058 : VIc photom. of IR-excess stars in NGC6611 (De Marchi+ 2013)
J/ApJS/208/28 : Hα survey in the ONC (Szegedi-Elek+, 2013)
J/ApJS/208/9 : Intrinsic colors and temperatures of PMS stars (Pecaut+, 2013)
J/MNRAS/415/103 : IPHAS T Tauri candidates in IC 1396 (Barentsen+, 2011)
J/ApJ/733/L8 : Optical and IR photometry of [KOS94] HA11 (Kun+, 2011)
J/PASJ/63/S1 : Atlas & catalog of dark clouds based on 2MASS (Dobashi+, 2011)
J/AJ/140/462 : Intermediate-mass star-forming regions (Arvidsson+, 2010)
J/ApJS/186/111 : Spitzer observations of Taurus members (Luhman+, 2010)
J/ApJS/185/451 : PMS stars in the Cepheus flare region (Kun+, 2009)
J/ApJS/184/18 : Spitzer survey of young stellar clusters (Gutermuth+, 2009)
J/A+A/504/461 : YSOs in L1630N and L1641 (Fang+, 2009)
J/AJ/137/4377 : List of SEGUE plate pairs (Yanny+, 2009)
J/ApJS/175/277 : Submillimeter-Continuum SCUBA detections (Di Francesco+, 2008)
J/A+A/452/245 : Near-IR photometry of PMS stars in rho Oph (Natta+, 2006)
J/ApJS/125/161 : A database of dense cores mapped in ammonia (Jijina+, 1999)
J/ApJS/101/117 : UBVRIJHKLMNQ photometry in Taurus-Auriga (Kenyon+ 1995)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 A3 --- ID Sequence number (1)
5- 20 A16 --- 2MASS 2MASS name (HHMMSSss+DDMMSSs; J2000)
22 A1 --- f_2MASS [a] Flag on 2MASS (2)
24- 38 A15 --- OName Other identifier
40 A1 --- f_OName [b] Flag on OName (2)
42- 52 A11 "Y/M/D" Date Date of the observation
54- 57 I4 0.1nm lambda1 Lower range of wavelength in Å
58 A1 --- --- [-]
59- 62 I4 0.1nm lambda2 Upper range of wavelength in Å
64- 83 A20 --- Tel Telescope/Instrument
--------------------------------------------------------------------------------
Note (1): "I" stands for "Candidate Intermediate-mass Young Stars" whereas
"T" indicates "Candidate Low-mass Pre-main Sequence Stars".
Note (2): Flag as follows:
a = This star was included into the target list due to the blue color indices
and projected location within the RNO 7 cluster.
b = Spectroscopic and photometric variability of [KOS94] HA 11 (V1180 Cas)
is described in Kun et al. (2011, J/ApJ/733/L8).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Seq [1/75] Running sequence number
4- 21 A18 --- Name Source 2MASS or SDSS identifier
(HHMMSSss+DDMMSSs or HHMMSS.ss+DDMMSS.s,
respectively; J2000) (2)
23 A1 --- f_Name [*] * = SDSS DR9 (V/139) identifier
25- 29 F5.1 0.1nm EW [7.8/496]? Hα equivalent width
31- 35 F5.1 0.1nm e_EW [0.6/110]? Uncertainty in EW
37- 84 A48 --- OName Other identifier or associated object name
--------------------------------------------------------------------------------
Note (2): (SDSS J)022932.28+725503.2 has been replaced by CDS,
by 022932.32+725503.3 for consistency with table 6 and SDSS DR9.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 A3 --- ID Sequence number (INN; "I" stands for
intermediate-mass young star candidate)
5- 20 A16 --- 2MASS 2MASS name (HHMMSSss+DDMMSSs; J2000)
22- 23 A2 --- SpT MK spectral type
25- 27 F3.1 mag Av Extinction in the V band
29- 33 I5 K Teff Effective temperature
35- 38 I4 K E_Teff Positive uncertainty on Teff
40- 43 I4 K e_Teff Negative uncertainty on Teff
45- 49 F5.1 Lsun L* Stellar luminosity
51- 55 F5.1 Lsun E_L* Positive uncertainty on L*
57- 61 F5.1 Lsun e_L* Negative uncertainty on L*
63- 65 F3.1 Msun M* Stellar mass
67- 70 A4 --- HRD Hertzsprung-Russell Diagram classification (1)
--------------------------------------------------------------------------------
Note (1): Class as follows:
ZAMS = zero-age main sequence
PMS = pre-main sequence
See section 4.1 for further explanations.
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Byte-by-byte Description of file: table4.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 A3 --- ID Sequence number (TNN; "T" stands for the
T Tauri type candidate)
5- 20 A16 --- 2MASS 2MASS name (HHMMSSss+DDMMSSs; J2000)
22- 23 A2 --- SpT MK spectral type
25- 29 F5.1 0.1nm EWHa [16/300] Hα equivalent width obtained
with longslit observations (see table 1)
31- 34 F4.1 0.1nm e_EWHa [0.6/15] EWHa uncertainty
36 A1 --- f_EWHa [b,c] Flag on EWHa (1)
38- 42 F5.1 0.1nm EW [17/496]? WFGS2 Hα equivalent width (2)
44- 48 F5.1 0.1nm e_EW [0.8/110]? EW uncertainty
--------------------------------------------------------------------------------
Note (1): Flag as follows:
b = Measured in the CAFOS spectrum.
c = Measured in the FAST spectrum.
Note (2): Same as listed for these stars in Table 2.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table6.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Seq [1/77] Running sequence number
4 A1 --- f_Seq [ab] Flag on Seq (1)
6- 23 A18 --- Name Source 2MASS or SDSS identifier
(HHMMSSss+DDMMSSs or HHMMSS.ss+DDMMSS.s,
respectively; J2000)
25- 26 A2 --- SpT MK spectral type (G1-M3)
28- 30 F3.1 mag Av [0.5/6.5]? Extinction in the V band
32- 35 I4 K Teff [3360/5970]? Effective temperature
37- 39 I3 K E_Teff [80/430]? Upper uncertainty in Teff
41- 43 I3 K e_Teff [80/480]? Lower uncertainty in Teff
45- 49 F5.2 Lsun L* [0.03/14.6]? Stellar luminosity
51- 55 F5.2 Lsun E_L* [0.02/10.3]? Upper uncertainty in L*
57- 60 F4.2 Lsun e_L* [0.01/6.1]? Lower uncertainty in L*
62- 65 F4.2 Msun M* [0.3/2.3]? Stellar mass
67- 70 F4.2 Msun E_M* [0.04/0.5]? Upper uncertainty in M*
72- 75 F4.2 Msun e_M* [0.05/0.5]? Lower uncertainty in M*
77- 81 F5.1 [Msun/yr] logMdot [-10.1/-5.8]? Log mass accretion rate
83- 86 A4 --- Class SED class (3)
--------------------------------------------------------------------------------
Note (1): Flag as follows:
a = [KOS94] HA 4, outside of the field of view of the WFGS2 observations.
b = [KOS94] HA 13, outside of the field of view of the WFGS2 observations.
Note (3): 1 source "I", 5 sources "Flat", 5 sources "III" and
34 sources "IIA" (weak), 21 sources "IIP" (primordial) and
9 sources "IIT" (transitional).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table9.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1 I1 --- Type [1/2] Stellar type (1)
3- 4 I2 --- Seq [1/75] Running sequence number
6- 11 F6.3 mag Umag [10.3/27.2] The U band magnitude
13- 17 F5.3 mag e_Umag [0.005/1.7] Uncertainty in Umag
19- 24 F6.3 mag Bmag [10/25] The B band magnitude
26- 30 F5.3 mag e_Bmag [0.006/0.3] Uncertainty in Bmag
32- 37 F6.3 mag Vmag [9.9/21.2] The V band magnitude
39- 43 F5.3 mag e_Vmag [0.006/0.3] Uncertainty in Vmag
45- 50 F6.3 mag Rcmag [9.8/19.9] The Rc band magnitude
52- 56 F5.3 mag e_Rcmag [0.007/0.05] Uncertainty in Rcmag
58- 63 F6.3 mag Icmag [9.6/19.1] The Ic band magnitude
65- 69 F5.3 mag e_Icmag [0.007/0.08] Uncertainty in Icmag
71- 74 A4 --- l_Jmag [≤] Limit flag on Jmag
76- 81 F6.3 mag Jmag [9.5/16.8]? The 2MASS J band magnitude
83- 87 F5.3 mag e_Jmag [0.02/0.2]? Uncertainty in Jmag
89- 94 F6.3 mag Hmag [9.5/16.2]? The 2MASS H band magnitude
96-100 F5.3 mag e_Hmag [0.02/0.3]? Uncertainty in Hmag
102-107 F6.3 mag Ksmag [9.2/15.4]? The 2MASS Ks band magnitude
109-113 F5.3 mag e_Ksmag [0.01/0.2]? Uncertainty in Ksmag
115-120 F6.3 mag 3.6mag [7.7/15.3]? Spitzer/IRAC 3.6um band magnitude
122-126 F5.3 mag e_3.6mag [0/0.2]? Uncertainty in 3.6mag
128-133 F6.3 mag 4.5mag [7/14.6]? Spitzer/IRAC 4.5um band magnitude
135-139 F5.3 mag e_4.5mag [0/0.08]? Uncertainty in 4.5mag
141-146 F6.3 mag 5.8mag [6.2/14.5]? Spitzer/IRAC 5.8um band magnitude
148-152 F5.3 mag e_5.8mag [0/0.2]? Uncertainty in 5.8mag
154-159 F6.3 mag 8.0mag [5.2/14.3]? Spitzer/IRAC 8.0um band magnitude
161-165 F5.3 mag e_8.0mag [0/0.09]? Uncertainty in 8.0mag
167-171 F5.3 mag 24mag [1.5/9.5]? Spitzer/MIPS 24 micron band magnitude
173-177 F5.3 mag e_24mag [0/0.2]? Uncertainty in 24mag
179-184 F6.3 mag 70mag [-0.2/8.7]? Spitzer/MIPS 70um band magnitude
186-190 F5.3 mag e_70mag [0.02/0.2]? Uncertainty in 70mag
192-197 F6.3 mag 3.4mag [7.5/15.3]? AllWISE W1 (3.4um) band magnitude
199-203 F5.3 mag e_3.4mag [0.01/0.04]? Uncertainty in 3.4mag
205-210 F6.3 mag 4.6mag [6.6/14.4]? AllWISE W2 (4.6um) band magnitude
212-216 F5.3 mag e_4.6mag [0.01/0.05]? Uncertainty in 4.6mag
218-221 A4 --- l_12mag [≥] Limit flag on 12mag
223-228 F6.3 mag 12mag [3.9/12.6]? AllWISE W3 (12um) band magnitude
230-234 F5.3 mag e_12mag [0.01/0.3]? Uncertainty in 12mag
236-239 A4 --- l_22mag [≥] Limit flag on 22mag
241-245 F5.3 mag 22mag [1.3/9.4]? AllWISE W4 (22um) band magnitude
247-251 F5.3 mag e_22mag [0.01/0.4]? Uncertainty in 22mag
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Note (1): Stellar type as follows:
1 = Intermediate-mass star;
2 = Hα emission star.
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History:
From electronic version of the journal
References:
Kun et al. Paper I. 1994A&A...292..249K 1994A&A...292..249K
Kun et al. NH3 cores. 2003A&A...398..169K 2003A&A...398..169K
Kun et al. Opt. view. 2016ApJ...822...79K 2016ApJ...822...79K This catalog
Kun et al. IR view. 2016ApJS..224...22K 2016ApJS..224...22K J/ApJS/224/22
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 05-Aug-2016