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J/AJ/114/1488             Globulars in M31 (Holland+ 1997)

Deep HST V- and I-band observations of two globular clusters in the halo of M31 Holland S., Fahlman G.G., Richer H.B. <Astron. J. 114, 1488 (1997)> =1997AJ....114.1488H
ADC_Keywords: Clusters, globular ; Photometry Mission_Name: HST Abstract: We present deep (V≃27) V- and I-band stellar photometry of G302 and G312, two globular star clusters in the halo of M31. These data were obtained using the Hubble Space Telescope's Wide Field/Planetary Camera 2. We find iron abundances of [Fe/H]=-1.85±0.12 for G302 and [Fe/H]=-0.56±0.03 for G312, consistent with spectroscopic measurements. The color-magnitude diagrams for each cluster show no evidence for an intermediate-aged population of stars, or a second parameter effect in the morphology of the horizontal branch. G302 shows no evidence for a color gradient but the inner regions of G312 are bluer than the outer regions. G312 shows no evidence of ellipticity or an extended halo of stars. G302 has a projected ellipticity of ε=0.195±0.012 with the projected major axis oriented towards the center of M31. G302 also shows evidence of an extended asymmetric stellar halo extending to at least twice the fitted Michie-King tidal radius. The amount of mass beyond the tidal radius of G302 is consistent with the stellar escape rates which have been predicted by N-body simulations of globular clusters in the Galactic tidal field. (c) 1997 American Astronomical Society. Objects: ---------------------------------------------------------- RA (2000) DE Designation(s) ---------------------------------------------------------- 00 45 25.2 +41 05 30 G302 = SKHB 302 = Bol 240 00 45 58.8 +40 42 32 G312 = SKHB 312 = Bol 379 ---------------------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table3.dat 64 13321 Stellar photometry for G302 and the surrounding fields table4.dat 64 3349 Stellar photometry for G312 and the surrounding fields table5.dat 70 626 Stellar photometry for G302 table6.dat 70 325 Stellar Photometry for G312 tables.tex 101 17741 AASTeX version of the tables tables.ps 72 29775 PostScript version of the tables
Byte-by-byte Description of file: table3.dat table4.dat
Bytes Format Units Label Explanations
1- 3 A3 --- CCD CCD the star was observed on 7- 10 I4 --- ID Identification number (1) 12- 18 F7.3 pix Xpos X pixel coordinate (2) 20- 26 F7.3 pix Ypos Y pixel coordinate (2) 28- 33 F6.3 mag Vmag V-band magnitude 35- 39 F5.3 mag e_Vmag 1-sigma uncertainty in Vmag 41- 45 F5.3 --- 2_Vmag Value of the DAOPHOT Chi statistics for Vmag 47- 52 F6.3 mag Imag I-band magnitude 54- 58 F5.3 mag e_Imag 1-sigma uncertainty in Imag 60- 64 F5.3 --- 2_Imag Value of the DAOPHOT Chi statistics for Imag
Note (1): Identification numbers are only unique for stars on a given CCD. Note (2): 1 pix = 0.1".
Byte-by-byte Description of file: table5.dat table6.dat
Bytes Format Units Label Explanations
1- 3 A3 --- CCD CCD the star was observed on 7- 10 I4 --- ID Identification number 12- 18 F7.3 pix Xpos X pixel coordinate (1) 20- 26 F7.3 pix Ypos Y pixel coordinate (1) 28- 32 F5.3 arcsec Dist Distance of star from cluster center 34- 39 F6.3 mag Vmag V-band magnitude 41- 45 F5.3 mag e_Vmag 1-sigma uncertainty in Vmag 47- 51 F5.3 --- 2_Vmag Value of the DAOPHOT Chi statistics for Vmag 53- 58 F6.3 mag Imag I-band magnitude 60- 64 F5.3 mag e_Imag 1-sigma uncertainty in Imag 66- 70 F5.3 --- 2_Imag Value of the DAOPHOT Chi statistics for Imag
Note (1): 1 pix = 0.1".
Origin: AAS CD-ROM series, Volume 9, 1997 Lee Brotzman [ADS] 04-Nov-1997
(End) [CDS] 05-Feb-1998
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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