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We present the preliminary results of more than 160 h of time-series photometry on the subdwarf B pulsating star PG 1325+101 (Teff= 34 500 K log g= 6.1), obtained in March-April 2003 at nine different sites. The amplitude spectrum confirms the presence of the four frequencies found in the discovery run at the NOT in July 2001 (but with significantly lower amplitudes in two of them) and also shows at least two new low amplitude signals. Moreover, there is no sign of frequency splitting near the main peak at 7256 μHz, suggesting that this mode might be actually radial as indicated by the time-resolved spectroscopy (Ostensen and Telting, 2004).

We report on the 323 hours of nearly uninterrupted time series photometric observations of the DBV star GD 358 acquired with the Whole Earth Telescope (WET) during May 23 to June 8, 2000. We acquired more than 232 000 independent measurements and detected the non-radial g-modes consistent with degree ℓ = 1 and radial order 8 to 20 and their linear combinations up to 6th order. We also detect, for the first time, a high amplitude ℓ = 2 mode, with a period of 796 s. In the 2000 WET data, the largest amplitude modes are similar to those detected with the WET observations of 1990 and 1994, but the highest combination order previously detected was 4th order.

We report 323 hours of nearly uninterrupted time series photometric observations of the DBV star GD 358 acquired with the Whole Earth Telescope (WET) during May 23rd to June 8th, 2000. We acquired more than 232 000 independent measurements. We also report on 48 hours of time-series photometric observations in Aug 1996. We detected the non-radial g-modes consistent with degree l=1 and radial order 8 to 20 and their linear combinations up to 6th order.We also detect, for the first time, a high amplitude l=2 mode, with a period of 796s. In the 2000 WET data, the largest amplitude modes are similar to those detected with the WET observations of 1990 and 1994, but the highest combination order previously detected was 4th order. At one point during the 1996 observations, most of the pulsation energy was transferred into the radial order k=8 mode, which displayed a sinusoidal pulse shape in spite of the large amplitude. The multiplet structure of the individual modes changes from year to year, and during the 2000 observations only the k=9 mode displays clear normal triplet structure. Even though the pulsation amplitudes change on timescales of days and years, the eigenfrequencies remain essentially the same, showing the stellar structure is not changing on any dynamical timescale., 34 pages, 14 figures, WET data, accepted to A&A

A small fraction of sdB stars show short-period, multiperiodic light variations and form the new class of pulsating star known as EC 14026 variables, after the prototype, or, alternately, as sdBV stars. Until recently, time-series observations of pulsating sdB stars have been limited to photometry (for a review see Charpinet et al., 2001). While emphasizing the great potential of asteroseismology with sdB variables (sdBV), Charpinet et al. also clearly demonstrate that the difficult process of mode identification, necessarily required for an asteroseismological study, is even more complicated for sdBV stars than for objects such as pulsating white dwarfs. While the latter tend to show a nearly equidistant mode pattern for consecutive overtones, no such relation is evident for sdBV stars. Consequently, observational methods beyond photometry alone are needed to further progress the interpretation of the sdBVs’ pulsational behaviour.

6th Whole Earth Telescope Workshop (WET) -- JUN 20-21, 2002 -- NAPLES, ITALY, WOS: 000184698800009, The Multi-site spectroscopic telescope is a virtual instrument and the name of a collaboration that opens up a new observational window by combining continuous observations of spectroscopic variations and simultaneous photometric monitoring. This constitutes an enormous observational effort, but in return promises to finally provide access to a mode identification for and an asteroseismological analysis of the pulsating sdB star PG 1605+072. Multi-Site Spectroscopic Telescope observations for this object have been secured during a large coordinated campaign in May and June of the year 2002. The frequency resolution and coverage of the photometric time series has been noticeably enhanced by a significant contribution from the Whole Earth Telescope, which was used to observe PG 1605+072 as an alternate target during the WET XCov22 campaign, also conducted in May 2002. This paper briefly outlines the motivation for the MSST project and tries to give a first assessment of the overall quality of the data obtained, with a focus on the Whole Earth Telescope observations.