Abstract. The first multisite photometric campaign devoted to the rapidly oscillating mass-accreting (primary) component of the Algol-type eclipsing binary system AS Eri has confirmed the presence of rapid pulsations with frequency 59.03116 d −1 , and revealed the second and third oscillation modes with frequencies 62.5631 d −1 and 61.6743 d −1 , respectively. These modes are related to the 5−6 overtone oscillations and are among the shortest periods excited in non-magnetic MS A-F stars. The nearly equator-on visibility of eclipsing binaries help to narrow the range of possible mode identifications for the detectable modes as radial or (l, m) = (1, ±1), (l, m) = (2, ±2) and (l, m) = (2, ±0). We checked the high-order pulsation-to-orbital synchronization (POS) using the trial mode identification and the Doppler effect correction for frequencies of non-radial pulsation. We found that (l, m, n) = (1, 1, 5) or (2, 2, 5) and (l, m, n) = (2, −2, 6) identifications for f 1 and f 2 modes respectively satisfied the highorder POS. These mode identifications are in agreement with the range of modes visible in disk integrated light of an equator-on visible pulsating component. The wavelength distribution of pulsation amplitudes in AS Eri is largest in the Strömgren u filter and decreases toward longer wavelengths. We place AS Eri and other known mass-accreting pulsating components of Algols on HR-diagram. They are located inside the instability strip on the Main Sequence. We also discuss the peculiar evolutionary status of primary components in Algols and stress that they are not normal δ Scuti stars, but form a separate group of pulsators. Finally, we discuss proximity and eclipse effects, and have simulated the effect of primary minimum data gaps that may produce the 1/P orb alias sidelobes in DFT analysis of eclipsing binary data. Aliases from gaps in primary minimum observations seem to be the principal limitation on spectral window functions in asteroseismic studies of eclipsing binaries.

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We present optical W BV R and infrared JHKL photometric observations of the Be binary system δ Sco, obtained in 2000-2005, mid-infrared (10 and 18 µm) photometry and optical (λλ 3200-10500 Å) spectropolarimetry obtained in 2001. Our optical photometry confirms the results of much more frequent visual monitoring of δ Sco. In 2005, we detected a significant decrease in the object's brightness, both in optical and near-infrared brightness, which is associated with a continuous rise in the hydrogen line strenghts. We discuss possible causes for this phenomenon, which is difficult to explain in view of current models of Be star disks. The 2001 spectral energy distribution and polarization are succesfully modeled with a three-dimensional non-LTE Monte Carlo code which

FS CMa stars form a group of objects with the B[e] phenomenon that were previously known as unclassified B[e] stars or B[e] stars with warm dust (B[e]WD) until recently. They exhibit strong emission-line spectra and strong IR excesses, most likely due to recently formed circumstellar dust. These properties have been suggested to be due to ongoing or recent rapid mass exchange in binary systems with hot primaries and various types of secondaries. The first paper of this series reported an analysis of the available information about previously known Galactic objects with the B[e] phenomenon, the initial selection of the FS CMa group objects, and a qualitative explanation of their properties. This paper reports the results of our new search for more FS CMa objects in the IRAS Point Source Catalog. We present new photometric criteria for identifying FS CMa stars as well as the first results of our observations of nine new FS CMa group members. With this addition, the FS CMa group has now 40 members, becoming the largest among the dust-forming hot star groups. We also present nine objects with no evidence for the B[e] phenomenon, but with newly discovered spectral line emission and/or strong IR excesses.