Context. The discovery of a short-period giant planet (a hot Jupiter) around the primary component of the triple star system HD 188753 has often been considered as an important observational evidence and as a serious challenge to planet-formation theories. Aims. Following this discovery, we monitored HD 188753 during one year to better characterize the planetary orbit and the feasibility of planet searches in close binaries and multiple star systems. Methods. We obtained Doppler measurements of HD 188753 with the ELODIE spectrograph at the Observatoire de Haute-Provence. We then extracted radial velocities for the two brightest components of the system using our multi-order, two-dimensional correlation algorithm, TODCOR. Results. Our observations and analysis do not confirm the existence of the short-period giant planet previously reported around HD 188753 A. Monte Carlo simulations show that we had both the precision and the temporal sampling required to detect a planetary signal like the one quoted. Conclusions. From our failure to detect the presumed planet around HD 188753 A and from the available data on HD 188753, we conclude that there is currently no convincing evidence of a close-in giant planet around HD 188753 A.

This paper presents a new algorithm, trimor, to analyse multi‐order spectra of triple systems. The algorithm is an extension of tricor, the three‐dimensional correlation technique that derives the radial velocities of triple stellar systems from single‐order spectra. The combined correlation derived from many orders enables the detection and the measurement of radial velocities of faint tertiary companions. The paper applied trimor to the already available spectra of HD 188753, a well‐known triple system, yielding the radial velocities of the faintest star in the system. This rendered the close pair of the triple system a double‐lined spectroscopic binary, which led to a precise mass ratio and an estimate of its inclination. The close‐pair inclination is very close to the inclination of the wide orbit, consistent with the assertion that this triple system has a close to coplanar configuration.

Acoustic wave propagation in a three-layer waveguiding configuration is analyzed. Considering an adhesive layer as a waveguide structure, it is shown that the propagation of guided modes is affected by the bonding quality. A comprehensive study demonstrates the possibility of utilizing measurements on guided wave propagation to detect interfacial weakness between an adhesive and adherend.

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