Access to Astronomical Catalogues

← Click to display the menu
J/AJ/96/1632        CCD BV photometry in M55    (Schade+ 1988)

A color-magnitude diagram for the halo globular cluster M 55 Schade D., Vandenberg D.A., Hartwick F.D.A. <Astron. J. 96, 1632 (1988)> =1988AJ.....96.1632S (SIMBAD/NED BibCode)
ADC_Keywords: Clusters, globular ; Photometry, CCD Abstract: We present new CCD photometry for the globular cluster M55 that extends well below the main-sequence turnoff. Combining these new data with previously published photographic photometry of cluster giants and horizontal-branch stars yields a high-quality composite color-magnitude diagram (CMD). A comparison of the latter with recent CMDs for M68 and NGC 6752-two clusters whose metallicities bracket that of M55-suggests (1) that the reddening to M55 may be as high as E(B-V)=0.14mag, and (2) that all three systems have similar ages. In particular, if the apparent distance modulus to M55 is (m-M)V=14.10mag, then isochrones for Y=0.24 and high [O/Fe] would suggest an age of ∼14Gyr. Very encouraging agreement of the observations with theoretical predictions is found. Objects: ---------------------------------------------------------- RA (2000) DE Designation(s) ---------------------------------------------------------- 19 39 59.3 -30 57 44 M 55 = NGC 6809 ---------------------------------------------------------- File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file table1 30 617 CCD photometry in M 55
Byte-by-byte Description of file: table1
Bytes Format Units Label Explanations
1- 3 I3 --- Star [1/617]+ Star number 5- 9 F5.1 pix Xpos X position (1) 11- 15 F5.1 pix Ypos Y position (1) 17- 22 F6.3 mag Vmag V magnitude 24- 29 F6.3 mag B-V B-V colour index
Note (1): 1 pix = 0.44"; X positive from West to East, Y from South to North.
History: Prepared via OCR at CDS.
(End) Marie-Jose Wagner, Patricia Bauer [CDS] 18-Apr-1997
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

catalogue service

© UDS/CNRS

Contact