A Caltech Library Service

Photometric and Hα observations of LSI+61°303: detection of a ~26 day V and JHK band modulation

Paredes, J. M. and Marziani, P. and Martí, J. and Fabregat, J. and Coe, M. J. and Everall, C. and Figueras, F. and Jordi, C. and Norton, A. J. and Prince, T. and Reglero, V. and Roche, P. and Torra, J. and Unger, S. J. and Zamanov, R. (1994) Photometric and Hα observations of LSI+61°303: detection of a ~26 day V and JHK band modulation. Astronomy and Astrophysics, 288 . pp. 519-528. ISSN 0004-6361.

PDF - Published Version
See Usage Policy.


Use this Persistent URL to link to this item:


We present new optical and infrared photometric observations and high resolution Hα spectra of the periodic radio star LSI+61°303. The optical photometric data set covers the time interval 1985-1993 and amounts to about a hundred nights. A period of ∼26 days is found in the V band. The infrared data also present evidence for a similar periodicity, but with higher amplitude of variation (0\rmag 2). The spectroscopic observations include 16 intermediate and high dispersion spectra of LSI+61°303 collected between January 1989 and February 1993. The Hα emission line profile and its variations are analyzed. Several emission line parameters -- among them the Hα EW and the width of the Hα red hump -- change strongly at or close to radio maximum, and may exhibit periodic variability. We also observe a significant change in the peak separation. The Hα profile of LSI+61°303 does not seem peculiar for a Be star. However, several of the observed variations of the Hα profile can probably be associated with the presence of the compact, secondary star.

Item Type:Article
Related URLs:
URLURL TypeDescription
Prince, T.0000-0002-8850-3627
Additional Information:© 1994 European Southern Observatory. Provided by the NASA Astrophysics Data System. Received 21 December 1993 / Accepted March 1994. We thank all observers who participated in the observations, especially Mauro D'Onofrio & Gabriele Cremonese for the spectra obtained at the Asaiago Observatory, and for help during part of the spectroscopic data reduction. We also thank R. Canal for valuable comments, as well as F. Comerón amd M. Fernández for participating in some photometric observations. JMP, JM, FF, CJ and JT acknowledge partial support by CICYT (ESP93-1020-E) and DGICYT (PB91-0857). Extraglactic Astronomy at the University of Alabama is supported under EPSCOR Grant R11-8996152. The TCS is operated on the island of Tenerife by the Instituto de Astrofísica de Canarias (IAC), in the Spanish Observatorio del Teide. The 1.5 m telescope at Palomar is jointly owned by California Institute of Technology and the Carnegie Institute of Washington. The CAHA 1.23 m telescope is operated by Max Planck Institute für Astronomie. The INT and JKT are operated on the island of La Palma by the Royal Greenwich Observatory in the Spanish ORM of the IAC. We also thank staff of the OAN 1.5 m telescope. Much of the data was analysed using the Southampton University Starlink node which is founded by the SERC. CE acknowledges the support of an SERC Studentship. We are also grateful for the support of the ING Service Programme that provided some of the data for this work.
Group:Space Radiation Laboratory
Funding AgencyGrant Number
Science and Engineering Research Council (SERC)UNSPECIFIED
Other Numbering System:
Other Numbering System NameOther Numbering System ID
Space Radiation Laboratory1994-10
Record Number:CaltechAUTHORS:20140609-163020996
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:46166
Deposited By: Deborah Miles
Deposited On:10 Jun 2014 20:28
Last Modified:03 Oct 2019 06:41

Repository Staff Only: item control page