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J/AJ/122/1330       HST BVI photometry of M 81 star clusters (Chandar+, 2001)

Compact star clusters in M81. I. Data from Hubble Space Telescope Wide Field Planetary Camera 2 imaging. Chandar R., Ford H.C., Tsvetanov Z. <Astron. J. 122, 1330 (2001)> =2001AJ....122.1330C
ADC_Keywords: Associations, stellar ; Photometry, Cousins Keywords: galaxies: individual (M81) - galaxies: star clusters - galaxies: stellar content Abstract: In this paper, we present the discovery of 114 compact star clusters in the nearby spiral galaxy M81 from B-, V-, and I-band Hubble Space Telescope Wide Field Planetary Camera 2 imaging in eight fields, covering a total area of ∼40arcmin2. The fields sample a variety of environments (both spiral and interarm regions), as well as a range of projected galactocentric distances from 2 to 12kpc. The sample is complete to V∼22, deeper by ∼1mag than any previous cluster survey in M81. We present details of the separation of clusters from both stellar sources and background galaxies, which has been based solely on structural parameters and morphology and not using any color cuts, as is necessary for ground-based surveys. We present magnitudes and colors of detected clusters. Surface brightness profiles are compared with single-mass King models, giving a range of core radii for the clusters in our sample between 0.2 and 7pc. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table2.dat 89 114 The cluster sample and properties table3.dat 47 11 Comparison of photometry with previous work
Byte-by-byte Description of file: table2.dat
Bytes Format Units Label Explanations
1- 3 I3 --- [CFT2001] Cluster identification number 5 I1 h RAh Right Ascension (J2000) 7- 8 I2 min RAm Right Ascension (J2000) 10- 14 F5.2 s RAs Right Ascension (J2000) 16 A1 --- DE- Declination sign (J2000) 17- 18 I2 deg DEd Declination (J2000) 20- 21 I2 arcmin DEm Declination (J2000) 23- 28 F6.3 arcsec DEs Declination (J2000) 30- 33 F4.1 kpc GCDis Deprojected galactocentric distance (1) 35- 40 F6.3 mag Vmag The V band magnitude (Johnson-Cousins) 42- 46 F5.3 mag e_Vmag Uncertainty in Vmag (2) 48 A1 --- f_Vmag [ab] Flag on Vmag (3) 50- 53 F4.2 arcsec ColRad The color radius 55- 60 F6.3 mag B-V The (B-V) color (Johnson-Cousins) 62- 66 F5.3 mag e_B-V Uncertainty in B-V (2) 68- 73 F6.3 mag V-I The (V-I) color (Johnson-Cousins) 75- 79 F5.3 mag e_V-I Uncertainty in V-I (2) 81- 84 F4.2 mag E(B-V) The local reddening (see section 3.7) 86- 88 F3.1 pc CoreRad Cluster core radius (see section 4)
Note (1): Provided the cluster is in the plane of M81. Note (2): The uncertainties take into account the object count rate, sky variance, and instrument gain. Uncertainty in color (in the given color radius) is estimated by propagating uncertainties in both filters to reflect the error in the two filter measurements. Note (3): Note on Vmag: a = Near edge of CCD. V magnitude given in 0.4" radius; b = V magnitude given in 0.7" radius.
Byte-by-byte Description of file: table3.dat
Bytes Format Units Label Explanations
1- 2 I2 --- [CFT2001] Cluster identification number 5- 10 F6.3 mag Vmag V magnitude (this work) 12- 16 F5.3 mag B-V B-V colour index (this work) 18- 24 A7 --- Name Other name (1) 26 A1 --- n_Name [a] Note on Name (2) 28- 32 F5.2 mag Vmag2 ? V magnitude (previous work) 34- 37 F4.2 mag B-V2 ? B-V colour index (previous work)
Note (1): Identifications: GTK NN = [GTK91b] NN, Georgiev et al., 1991PAZh...17..387G IdNNNNN = [PBH95] NNNNN Perelmuter et al., 1995AJ....110..620P Note (2): There are two objects listed with the same name (GTK 48) in the Georgiev et al. (1993BSAO...36...43G) work. These were matched to our objects by coordinates.
History: From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Bauer [CDS] 14-Jan-2002
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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