In this review paper, we summarise the goals of asteroseismic studies of close binary stars. We first briefly recall the basic principles of asteroseismology, and highlight how the binarity of a star can be an asset, but also a complication, for the interpretation of the stellar oscillations. We discuss a few sample studies of pulsations in close binaries and summarise some case studies. This leads us to conclude that asteroseismology of close binaries is a challenging field of research, but with large potential for the improvement of current stellar structure theory. Finally, we highlight the best observing strategy to make efficient progress in the near future.

Activity of late type stars is enhanced by fast rotation, which is maintained in nearly synchronized close binary systems. Magnetic activity originates in the deep convection zones of stars from where magnetic flux tubes emerge to their surfaces. The gravitational forces in binaries help the clustering of activity features giving rise to active longitudes. These preferred longitudes are observed in binaries from dwarfs to giants. Differential rotation is found in many active stars that are components of binary systems. If these binaries are circularized and nearly synchronized, then there will be a corotation latitude in their surfaces, and its position can be determined by observations and by theoretical calculations. Enhanced activity in binaries could have a reverse effect as well: strong magnetism in a binary component can modify the orbital period by the cyclic exchange of kinetic and magnetic energy in its convective envelope.

We present results from an investigation where the long-term photometry of several magnetically active RS CVn binaries is studied to see whether or not they show permanent active longitudes and the flip-flop phenomenon. We confirm that it is very common for the active regions to occur on permanent active longitudes. Many of our target stars also show clear flip-flop phenomenon, but often the data set is not long enough for reliable determination of the flip-flop period.

Using the ASAS-3 photometry, we find the components of four eclipsing binary systems — V916 Cen, HD 101838, V4386 Sgr and HD 168050 — to be β Cephei-type pulsators. The first two systems are members of the young open cluster Stock 14. The pulsating stars are presumably the primary, more massive components in all these systems. The components are detached and for at least two systems, V916 Cen and HD 168050, we may suspect that they will appear to be double-lined spectroscopic ones. In consequence, these stars become very attractive targets for studying pulsations in β Cephei stars by means of asteroseismology.

This summary covers the first two days of the Symposium, in which the oral papers were primarily observational in nature. It also mentions several of the many observational posters associated with those discussions.

The winding up of a conference like this provides the opportunity to look (1) backwards at how we reached the present stage of understanding of binary star behavior and its relationship to the rest of astronomy, (2) around at the garden of unsolved problems, and (3) cautiously forward at what might come next.

So at last we come to the end of our meeting! I have the honor of being the last speaker at Symposium 240, and apparently the last speaker of the GA itself! I will keep my comments very brief, so that you all may experience a few more minutes of sightseeing or perhaps another fine Czech beer before beginning your travels home.

Wulff Dieter Heintz, Professor Emeritus of Astronomy at Swarthmore College, passed away at his home on 10 June 2006, following a two-year battle with lung cancer. He had just turned 76 a week earlier. Wulff was one of the leading authorities on visual double stars, and was also a chess master. A prominent educator, researcher, and scholar, Wulff was noted for being both succinct and meticulous in everything he did. Wulff Heintz was born on 3 June 1930 in Würzburg (Bavaria), Germany. Naturally left-handed, the young Wulff's elementary school teachers forced him to learn to write “correctly” using his right hand, and so he became ambidextrous. During the 1930s, Wulff's family saw the rise of Adolph Hitler and lived under the repressive Nazi regime. Conditions were austere, and it was often difficult to find fuel to keep the house warm. As a teenager during World War II, Wulff listened to his family radio for any news from the outside world. He used to say that he loved the blackouts during the bombing runs because it made it much easier to see the stars. One night, an incendiary bomb landed on the roof of his family home, and Wulff climbed up to the roof and extinguished it. The next morning, he saw that his high school had been completely leveled by Allied bombs. As Germany continued to suffer massive losses on the Russian Front, primarily due to unexpectedly severe winters, teenage boys were inducted into the military and sent off to replenish the troops. To avoid an uncertain fate, Wulff hid out in a farmhouse in the countryside outside Munich. When the Allied troops invaded Germany in 1945, the young Wulff volunteered to translate information from the American and British soldiers to the local villagers. During this time, the soldiers taught Wulff how to smoke cigarettes, a habit which he continued until his final days, even after having been diagnosed with lung cancer.

We present a comparison of selected methods for measuring radial velocities in stellar spectra. We compare cross-correlation, line-profile fitting with Gauss, Lorentz and Voigt functions and a less-known mirroring method. We discuss their applicability and precision and indicate their advantages and disadvantages. The mirroring method proved to be useful for the analysis of Be stars, but is not implemented in any major astronomical packages.

The first results of speckle interferometry carried out with the 3.5-m telescope of the C.A.H.A. (Almería, Spain) during a run in July, 2005 are presented. Forty nine stars with separations between 0″058 and 2″1 were observed under good seeing conditions. On the basis of these observations three improved orbits are presented. The Time Allocation Committee's report with a high scientific qualification to our proposal is included. It confirms the relevance of binary and multiple star research in modern astronomy and the great significance of large telescopes in this kind of studies as well.

Binary and multiple systems constitute one of the main tools for obtaining fundamental stellar parameters, such as masses, radii, effective temperatures and distances. One especially fortunate, and at the same time rare, occurrence is that of double-lined eclipsing binaries with well-detached components. In this special case, it is possible to obtain a full solution of all orbital and stellar parameters, with the exception of the effective temperature of one star, which is normally estimated from spectral type or derived from atmospheric analysis of the spectrum. Long-baseline interferometry at facilities such as the ESO VLTI is beginning to have the capability to measure directly the angular separation and the angular diameter of some selected eclipsing binary systems, and we have proposed such observations with the AMBER instrument. In particular, we aim at deriving directly the effective temperature of at least one of the components in the proposed system, thereby avoiding any assumptions in the global solution through the Wilson–Devinney method. We will also obtain an independent check of the results of this latter method for the distance to the system. This represents the first step towards a global calibration of eclipsing binaries as distance indicators. Our results will also contribute to the effective temperature scale for hot stars. The extension of this approach to a wider sample of eclipsing binaries could provide an independent method to assess the distance to the LMC. The observations will extend accurate empirical calibration to spectral type O9 – B0.

We obtained new series of electronic spectra and UBV photometry of V379 Cep and analyzed them in an effort to check whether the conclusion about its anomalous masses is not premature. We found that the second system of spectral lines seen in the spectra of V379 Cep does not belong to the secondary but to the primary of another binary Ba+Bb (orbital period of 159d0) which constitutes a quadruple system with the narrow-lined 99d76 eclipsing binary Aa+Ab (for which we report probable detection of the secondary and derive improved period and orbital elements). The mutual motion of the two binaries A+B around the common centre of gravity is also observable and the probable orbital period is some 7878 days. Our result shows that the components Aa and Ba are somewhat evolved but removes the reported discrepancy of anomalously small masses. We find that V379 Cep is an astrophysically interesting quadruple system for which a future combination of interferometry, spectroscopy and photometry can provide individual masses of all four bodies.

The method of spectra disentangling has been applied in many studies on different stellar systems up to the distance of Andromeda Galaxy. In some of these applications the underlying assumptions are not precisely satisfied. This is why new generalizations of the method are needed. Ways to overcome these problems are discussed here.

In a synthesis article (see ref. below), the double star expert Paul COUTEAU put the work of French pioneers of double stars observation in the perspective of the double star work carried in the world. After Antoine Yvon VILLARCEAU and Camille FLAMMARION, one prominent pioneer of double stars was Robert JONCKHEERE (1888–1974), an amateur before circumstances prompted him to become a professional astronomer, who devoted his life to double stars. Kenneth Glyn Jones wrote a biography and Charles Fehrenbach his obituary. Jean-Claude Thorel studied his life and career in double star observations (see Section 10 below). In the 1930s, another precursor of the Commission des Étoiles Doubles, Maurice DURUY (1894–1984) invented the micrometer with a comparison star, and applied the diffraction micrometer invented by Ejnar Hertzsprung to the measure of double stars, which he regularly observed at Nancy with a 275-mm telescope, at Lyon with a 162-mm telescope and in his observatory of Beaume-Mêle with a 40-cm and later a 60-cm telescope at Le Rouret (Alpes–Maritimes). He measured standard pairs of the list of Paul Muller and published his measures in the Journal des Observateurs; these measures requested by Paul Muller aimed at comparisons of between observers. He also collaborated with the Webb Society of Great Britain; Glyn Jones published his astronomical biography. Already in 1924, the pediatrician Paul BAIZE (1901–1995) had started the measurement of double stars as an amateur. He was granted permission to measure them with the 38-cm of the Paris Observatory and made an impressive number of measures during his long “career" (24044). He also made orbit calculations and established a formula for the calculation of dynamic parallaxes in 1946. He wrote articles explaining new observation techniques devoted to double stars in the magazine L'Astronomie and continued his astronomical activity until the beginning of the 1990s. Glyn Jones published an astronomical biography of Paul Baize. In the 1960s, Bernard CLOUET and the late Robert SAGOT (1910–2006) made double star observations for the book which was then in preparation under the title La revue des constellations. Their measures remained unpublished; but publication of the measures made by Robert SAGOT is in preparation. At about the same time, the neurology professor Jacques LE BEAU (1908–1998) made the acquaintance of renowned professional astronomer Paul COUTEAU and learned from him how to measure double stars. Each year, he stayed for two weeks at Nice and conducted his observations with the 50-cm refractor of the Nice Observatory. In 1978, Paul COUTEAU published the first book in French devoted to double stars: L'observation des étoiles doubles visuelles. That book triggered the interest of more amateur astronomers for double stars and indirectly influenced the creation of a group of double star observers which was transformed into the Commission des Étoiles Doubles

We report on the results of our 2004 monitoring program of M22, designed to search for CVs undergoing dwarf nova (DN) eruptions. We wish to compare these globular cluster systems to similar ones in the field and determine if their different formation mechanisms result in different properties. We present a light curve for a CV candidate that went into outburst during May. Data were reduced with the ISIS image subtraction routine. Our ground-based results are consistent with previous HST measurements, and confirm the DN nature of the outburst. We also report on further attempts to apply the ISIS software to look for additional outbursts of this object during 2004 as well as to identify other variable candidates in the core of M22.

The orbital eccentricity of the SB1 system ζ TrA (S.T. F9V, P ∼ 13 d) was found by Skuljan et al. (2004) to be e = 0.01398 ± 0.00019. Lucy (2005) devised a statistical test of the significance of this result, based on the amplitude and phase of the third harmonic in the Fourier analysis of the radial velocity data, and concluded that the non-zero eccentricity measured does not arise from a slightly eccentric Keplerian orbit, but from proximity effects in the binary. He therefore believes a circular orbit should be assigned to this system. In this paper we investigate one possible proximity effect, namely the tidal distortion of the primary star, such that the measured Doppler shift does not accurately indicate the centre of mass radial velocity of the star as a whole. The code of Wilson & Devinney (2003) was used to model the tidal distortion of the measured radial velocities, assuming a range of possible secondary masses, corresponding to M-dwarf companions. The result is that even for the lowest possible mass secondary of 0.09M⊙ with sin i = 1 (this gives the greatest tidal distortion, as it is closest to the primary) there is no significant effect on the radial velocities (the differences are of order 1 m s−1 as a result of the tidal effects). Similar negligible tidal effects arise using a white dwarf companion. We note that the difference between a circular orbit and the observations amounts to as much as 140 m s−1 at some phases, which is essentially the amplitude of the second harmonic in the data. Our conclusion is that this strong and highly significant second harmonic is most probably the result of a small orbital eccentricity as reported by Skuljan et al (2004). We note that the observed third harmonic according to Lucy (2005) has an amplitude of only 5.2 ± 2.0 m s−1, which is just over twice the error bar of its measurement, and that the predicted third harmonic for an eccentric orbit is only 1.6 m s−1.

We report on time-resolved CCD photometry of the newly-discovered dwarf nova, TSS J022216.4+412259.9 during its outburst in 2005 November–December. The best-estimated superhump period was 0.0554 days, which is the shortest superhump period among WZ Sge-type dwarf novae ever known. Double-peaked humps were also detected with a period of 0.05487 days in the early stage of the outburst. A rebrightening exhibited after the end of the plateau phase. All of these observations indicate the WZ Sge nature of the system. We mainly discuss the rebrightening stage of the superoutburst, compared with other WZ Sge-type dwarf novae.

The spectrum of the classical λ Boo star HD 204041 is revealed to be a composite one.