Hostname: page-component-84b7d79bbc-lrf7s Total loading time: 0 Render date: 2024-07-28T00:45:09.294Z Has data issue: false hasContentIssue false
  • English
  • Français

An Historical Light Curve of CF Octantis from Digitised Images of the Bamberg Plate Archive

Published online by Cambridge University Press:  05 March 2013

J. L. Innis ,
P. Heil ,
K. Thompson  and
D. W. Coates
J. L. Innis*
Affiliation:
Geophysical Institute, University of Alaska Fairbanks, Fairbanks AK 99775, USA
P. Heil
Affiliation:
IARC, University of Alaska Fairbanks, Fairbanks AK 99775, USA
K. Thompson
Affiliation:
School of Physics and Materials Engineering, Monash University, Melbourne VIC 3168, Australia
D. W. Coates
Affiliation:
School of Physics and Materials Engineering, Monash University, Melbourne VIC 3168, Australia
*
FE-mail: john.innis@aad.gov.au
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Digital images were made of Bamberg Observatory Sky Patrol plates of the field surrounding the active-chromosphere star CF Octantis (HD 196818). These images, taken with an inexpensive camera, were analysed using standard aperture photometry techniques. Good agreement was found with catalogued photographic magnitudes for stars in the range mpg ∼8.5 to ∼10.5. The root-mean-square deviations in the measured differences for non-variable field stars was found to be of order 0.10 mag, although a small number of larger differences occurred. For CF Oct, a period search of data from 1966 recovered the known 20 d variation due to starspot rotational modulation, with a range of variation of order 0.5 mag photographic. For active-chromosphere stars with moderately large photometric variations (>∼0.3 mag), and moderate to long rotation periods (>∼1 week), careful analysis of similarly obtained digital copies of archive plates may provide valuable insights into historical actvity.

Keywords

stars: activitystars: individual (CF Oct)stars: spotstechniques: photometric
Type
Research Article
Information
Publications of the Astronomical Society of Australia , Volume 21 , Issue 3 , 2004 , pp. 284 - 289
Copyright
Copyright © Astronomical Society of Australia 2004

References

Bidelmann, W. P., & MacConnell, D. J. 1973, AJ, 78, 687 Google Scholar
Burkholder, V. 1995, JAAVSO, 23, 127 Google Scholar
Collier, A. C. 1982, PhD Thesis (Christchurch: Univ. of Canterbury)Google Scholar
Hearnshaw, J. B. 1979, Changing Trends in Variable Star Research, Proc IAU Colloq. 46, eds. F. M. Bateson, J. Smak, & I. H. Urch (Hamilton: Univ. of Waikato), 371 Google Scholar
Innis, J. L., Coates, D. W., Dieters, S. W. B., Moon, T. T., & Thompson, K. 1983, IBVS, 2386 Google Scholar
Innis, J. L., Coates, D. W., & Thompson, K. 1997, MNRAS, 285, 515 Google Scholar
Kroll, P., la Dous, C., & Brauer, H.-J. (eds.) 1999, Treasure-Hunting in Astronomical Plate Archives (Frankfurt am Main: Deutsch)Google Scholar
Lloyd Evans, T., & Koen, M. C. J. 1987, SAAO Circ., 11, 21 Google Scholar
Pollard, K. R., Hearnshaw, J. B., Gilmore, A. C., & Kilmartin, P. M. 1989, JA&A, 10, 139 Google Scholar
Schoffel, E. 1964, IBVS, 71 Google Scholar
Schoeffel, E., & Koehler, U. 1965, IBVS, 100 Google Scholar
Slee, O. B., Nelson, G. J., Stewart, R. T., Wright, A. E., Innis, J. L., Ryan, S. G., & Vaughan, A. E. 1987a, MNRAS, 229, 659 Google Scholar
Slee, O. B., Nelson, G. J., Stewart, R. T., Wright, A. E., Jauncey, D. L., Vaughan, A. E., Large, M. I., Bunton, J. D., Peters, W. L., & Ryan, S. G. 1987b, PASA, 7, 55 Google Scholar
Stellingwerf, R. F. 1979, ApJ, 227, 935 Google Scholar
Stoy, R. H. 1966, Ann. Cape Obs., 21 Google Scholar
Stoy, R. H. 1968, Ann. Cape Obs., 22 Google Scholar
Strohmeier, W. 1967, IBVS, 178 Google Scholar
Strohmeier, W., & Mauder, H. 1969, Sky. Tel., 37, 10 Google Scholar