SpringerLink
ForumSpringerAstron. Astrophys.
ForumWhats NewSearchOrders


Astron. Astrophys. 326, 698-708 (1997)

Next Section Table of Contents

Period changes of AR Lacertae between 1900 and 1989

L. Jetsu 1, I. Pagano 2, D. Moss 3, M. Rodonò 2, 4, A.F. Lanza 2 and I. Tuominen 5

1 NORDITA, Blegdamsvej 17, DK-2100 Copenhagen, Denmark
2 Osservatorio Astrofisico di Catania, Città Universitaria, I-95125, Catania, Italy
3 Mathematics Department, The University, Manchester M13 9PL, UK
4 Istituto di Astronomia, Università degli Studi, Viale A. Doria, 6, I-95125 Catania, Italy
5 Department of Geosciences and Astronomy, University of Oulu, P.O. Box 333, FIN-90571 Oulu, Finland

Received 6 June 1996 / Accepted 29 April 1997

Abstract

The epochs of the primary and secondary minima of AR Lac  between 1900 and 1989 are analysed with two nonparametric methods of searching for periodicity in a weighted time point series. An analytical model for transforming the [FORMULA]  data of eclipsing binaries into the period domain is presented and is applied to AR Lac. The abrupt period changes of AR Lac  reported in several previous studies are most probably a consequence of an oversimplified interpretation of the [FORMULA]  data, since these changes are as likely to be continuous, and even the possibility of a 36 [FORMULA] cycle in the period cannot be definitely ruled out.

Key words: stars: AR Lacertae -- binaries: eclipsing -- methods: analytical; statistical

Send offprint requests to: L. Jetsu (jetsu@nordita.dk)

SIMBAD Objects

Contents

Next Section Table of Contents

© European Southern Observatory (ESO) 1997

Online publication: October 15, 1997
helpdesk.link@springer.de