J/MNRAS/438/1451 UBVIHα photometry of IC 1848 (Lim+, 2014)
Sejong Open Cluster Survey (SOS).
II. IC 1848 cluster in the HII region W5 West.
Lim B., Sung H., Kim J.S., Bessell M.S., Karimov R.
<Mon. Not. R. Astron. Soc., 438, 1451-1465 (2014)>
=2014MNRAS.438.1451L 2014MNRAS.438.1451L
ADC_Keywords: Clusters, open ; Photometry, UBVRI ; Photometry, H-alpha
Keywords: accretion, accretion discs - circumstellar matter -
stars: luminosity function, mass function -
open clusters and associations: individual: IC 1848
Abstract:
IC 1848 is one of the young open clusters in the giant star-forming
Cas OB6 association. Several interesting aspects relating to star
formation processes in giant star-forming regions attracted us to
study the initial mass function (IMF), star formation mode and
properties of pre-main-sequence (PMS) stars. A UBVI and Hα
photometric study of the young open cluster IC 1848 was conducted as
part of the 'Sejong Open Cluster Survey'. We have selected 105
early-type members from photometric diagrams. Their mean reddening is
<E(B-V)≥0.660±0.054mag. Using the published photometric data with
near- and mid-infrared archival data we confirmed the normal reddening
law (RV=3.1) towards the cluster (IC 1848). A careful zero-age
main-sequence fitting gives a distance modulus of
V0-MV=11.7±0.2mag, equivalent to 2.2±0.2kpc. Hα
photometry and the list of young stellar objects identified by Koenig
et al. permitted us to select a large number of PMS stars comprising
196 Hα emission stars, 35 Hα emission candidates, 5 Class
I, 368 Class II and 24 transition disc candidates. From the
Hertzsprung-Russell diagram using stellar evolution models, we
estimate an age of 5Myr from several evolved stars and 3Myr from the
PMS stars. The IMF was derived from stars with mass larger than
3M☉, and the slope is slightly steeper (Γ=-1.6±0.2) than
the Salpeter/Kroupa IMF. Finally, we estimated the mass accretion rate
of PMS stars with an ultraviolet excess. The mean mass accretion rate
is about 1.4x10-8M☉/yr in the mass range of 0.5-2M☉,
whereas intermediate-mass stars (≥2.5M☉) exhibit a much higher
accretion rate of dM/dt>10-6M_☉/yr.
Description:
The observations of two regions associated with IC 1848 were made on
2009 January 19 using the AZT-22 1.5-m telescope (f/7.74) at Maidanak
Astronomical Observatory in Uzbekistan. All imaging data were acquired
using the Fairchild 4098x4098 CCD (SNUCam) with standard Bessell
UBVI and Hα filters.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 149 15010 Photometric data
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 5 I5 --- ID [-12/14998] Sequential number (1)
7- 8 I2 h RAh Right ascension (J2000)
10- 11 I2 min RAm Right ascension (J2000)
13- 17 F5.2 s RAs Right ascension (J2000)
19 A1 --- DE- Declination sign (J2000)
20- 21 I2 deg DEd Declination (J2000)
23- 24 I2 arcmin DEm Declination (J2000)
26- 29 F4.1 arcsec DEs Declination (J2000)
31- 36 F6.3 mag Vmag [7/22.8]?=- V magnitude
38- 43 F6.3 mag Imag [10/21.1]?=- I magnitude
45- 49 F5.3 mag V-I ?=- V-I colour index
51- 55 F5.3 mag B-V ? B-V colour index
57- 62 F6.3 mag U-B ? U-B colour index
64- 69 F6.3 mag Ha-C ? Hα colour index (C=(V+I)/2)
71- 75 F5.3 mag e_Vmag ?=- rms uncertainty on Vmag
77- 81 F5.3 mag e_Imag ?=- rms uncertainty on Imag
83- 87 F5.3 mag e_V-I ?=- rms uncertainty on V-I
89- 93 F5.3 mag e_B-V ?=- rms uncertainty on B-V
95- 99 F5.3 mag e_U-B ?=- rms uncertainty on U-B
101-105 F5.3 mag e_Ha-C ?=- rms uncertainty on H-C
107 I1 --- o_Vmag Number of observations for Vmag
109 I1 --- o_Imag Number of observations for Imag
111 I1 --- o_V-I Number of observations for V-I
113 I1 --- o_B-V Number of observations for B-V
115 I1 --- o_U-B Number of observations for U-B
117 I1 --- o_Ha-C Number of observations for H-C
119-134 A16 --- 2MASS 2MASS name (HHMMSSss+DDMMSSs)
136 A1 --- Ha [Hh] Hα emission flag (2)
138-149 A12 --- SpT Spectral type for stars -1 to -12 (3)
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Note (1): The negative numbered ID represents the data from
Johnson & Hiltner (1956ApJ...123..267J 1956ApJ...123..267J); Hoag et al. (1961PUSNO..17..343H 1961PUSNO..17..343H);
Bigay (1963JO.....46..319B 1963JO.....46..319B); Haug (1970A&AS....1...35H 1970A&AS....1...35H);
Hog et al. (2000A&A...355L..27H 2000A&A...355L..27H, Cat. I/259).
Note (2): Hα flag is:
H = Hα emission stars
h = Hα emission star candidates
Note (3): Spectral type for stars -1 to -12, from
Morgan et al. (1955ApJS....2...41M 1955ApJS....2...41M);
Hoag & Applequist (1965ApJS...12..215H 1965ApJS...12..215H);
Fehrenbach (1966POHP....8...25F 1966POHP....8...25F);
Conti & Leep (1974ApJ...193..113C 1974ApJ...193..113C);
Reed (2003AJ....125.2531R 2003AJ....125.2531R, Cat. V/125);
Hillwig et al. (2006ApJ...639.1069H 2006ApJ...639.1069H, Cat. J/ApJ/639/1069).
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History:
From electronic version of the journal
References:
Sung et al., 2013JKAS...46..103S 2013JKAS...46..103S (target selection and data analysis)
Sung et al., Paper I 2011JKAS...44...39L 2011JKAS...44...39L (NGC 2353)
Lim et al., Paper III 2014MNRAS.443..454L 2014MNRAS.443..454L (NGC 1893)
Lim et al., Paper IV 2015AJ....149..127L 2015AJ....149..127L, Cat. J/AJ/149/127
(End) Patricia Vannier [CDS] 05-Dec-2014