We carried out an extensive photometric and spectroscopic investigation of the SPB binary, HD 25558 (see Fig. 1 for the time and geographic distribution of the observations). The ~2000 spectra obtained at 13 observatories during 5 observing seasons, the ground-based multi-colour light curves and the photometric data from the MOST satellite revealed that this object is a double-lined spectroscopic binary with a very long orbital period of about 9 years. We determined the physical parameters of the components, and have found that both lie within the SPB instability strip. Accordingly, both components show line-profile variations consistent with stellar pulsations. Altogether, 11 independent frequencies and one harmonic frequency were identified in the data. The observational data do not allow the inference of a reliable orbital solution, thus, disentangling cannot be performed on the spectra. Since the lines of the two components are never completely separated, the analysis is very complicated. Nevertheless, pixel-by-pixel variability analysis of the cross-correlated line profiles was successful, and we were able to attribute all the frequencies to the primary or secondary component. Spectroscopic and photometric mode-identification was also performed for several of these frequencies of both binary components. The spectroscopic mode-identification results suggest that the inclination and rotation of the two components are rather different. While the primary is a slow rotator with ~6 d rotation period, seen at ~60° inclination, the secondary rotates fast with ~1.2 d rotation period, and is seen at ~20° inclination. Our spectropolarimetric measurements revealed that the secondary component has a magnetic field with at least a few hundred Gauss strength, while no magnetic field was detected in the primary.

The detailed analysis and results of this study will be published elsewhere.

In Manchester, a WG was set up to work on the implementation of the 9th catalogue of orbits of spectroscopic binaries (SB9), superseding the 8th release of Batten et al. (1989) (SB8). SB9 exists in electronic format only. The web site http://sb9.astro.ulb.ac.be was officially released during Summer 2001. This site is directly accessible from the Commission 26 web site, from BDB (in Besancon) and from the CDS (at least).

The Business Meeting of Commission 26 took place on 17 August 2006, during the IAU XXVI General Assembly in Prague. It was chaired by its outgoing president, William Hartkopf, and was attended by the following members and guests: H. Abt, C. Allen, W. van Altena, R. Argyle, G. van Belle, D. Bisikalo, A. Bradley, T. ten Brummelaar, D. Cline, T. Corbin, R. Costero, J. Davis, H. Dickel, J. Docobo, J. Echevarria, F. Fekel, E. Griffin, P. Harmanec, W. Hartkopf, P. Lampens, O. Malkov, B. Mason, H. McAlister, T. Oswalt, D. Pourbaix, A. Poveda, D. Raghavan, W. Sanders, C. Scarfe, W. Tango, A. Tokovinin, S. Urban, R. Wilson, and H. Zinnecker.

This report from Commission 30 covers the salient areas in which major progress has been made in the triennium covered by the present volume. The principal scientific areas are: The Milky Way, star clusters, spectroscopic binaries, extrasolar planets, pulsating stars and stellar oscillations. Following these, an account is given of the progress in techniques and methodology for radial velocity determinations. Finally, a summary is given of the progress made by the working groups of the Commission, followed by a list of key papers in the triennium. A more extensive report also covering extragalactic work, which due to unforeseen circumstances could not be included here, can be found at the web page of Commission 30 (http://www.iau.org/IAU/Organization/divcom/).

With a large number of newly detected red variables in globular clusters we construct a log P – K diagram of these stars and compare it with findings from the LMC. We show the existence of a relation between the location in log P – K diagram and the velocity amplitude in the near infrared.

Observations of lithium in sunspots resulted in the prediction of significant lithium equivalent-width variability in chromospherically active stars. Lithium observations of several types of active stars, such as pre-main-sequence stars and late-type dwarfs in very young clusters, whose members are assumed to be nearly coeval, as well as post-main-sequence objects, show a significant range of abundances. Thus, a number of researchers over the past decade have investigated star spots as the possible cause of the various observed lithium-abundance spreads. Observationally, some evidence has been found for lithium equivalent-width variations. Computed synthetic spectra indicate that under certain conditions significant variations should be detected, but such conditions are not often met except perhaps in the most active stars. While variations have been claimed for some T Tauri stars, simultaneous photometry and spectroscopy will be needed to explore the complex relation of spots and lithium-abundance variations. The fact that some post-main-sequence stars have lithium abundances similar to those of pre-main-sequence stars complicates the identification of isolated pre-main-sequence systems.

HR 6469 consists of an evolved G5 star and a close pair of fainter stars, probably both on the main sequence. The period of the close pair is just over two days, and shallow eclipses have been detected (Boyd et al. 1985), although no analysis of the light curve has been published. The wide system has a period of about 5.5 years, and has been resolved by speckle interferometry (McAlister et al. 1983). The G5 star and the primary of the close pair are detectable in the spectrum, with the latter showing modest rotational broadening. Spectral types and rotational velocities for the evolved star and the brighter component of the close pair have been published by Strassmeier & Fekel (1990).

The visual binary Psi Sagittarii (ADS 12214, HR 7292) is a spectroscopic triple system with orbital periods of 10.78 days and 20.0 years. Periastron passage in the long period crbit occurred on JD 2442410 ± 30 days. Masses derived from the parameters of the spectroscopic and visual orbits are 2.7 m⊙ for the visual primary, 2.1 m⊙ for the short period pair primary, and 1.7 m⊙ for the short period pair secondary. The distance to the system is 100 parsecs. The orbital inclination of the close pair is nearly the same numerically as that of the visual orbit. Suggested spectral classifications indicate that all three components have evolved off the main sequence. Mass exchange in the close pair has not yet occurred.