An analysis is made of the spectral line shapes of τ Bootis using high resolution (0.026 Å) and high signal-to-noise (S/N ≈ 400) data in an effort to confirm the planet hypothesis for this star. Changes in the line shape are quantified using spectral line bisectors and line residuals. We detect no variations in either of these quantities above the level of the noise in the data. One spectral li...

Received ; accepted – 2 – ABSTRACT We have studied five seasons of OGLE-III data for eight SMC Be/X-ray pulsars for which no other survey data were available. We have determined orbital periods for four of these binary systems, one of which also shows nonradial pulsations. Optical identification of SMC X-2 is reconsidered, but no periods were found for either of the two possible candidates.

We construct solutions to the two-dimensional parabolic-elliptic Keller-Segel model for chemotaxis that blow up in finite time T. The solution is decomposed as sum of a stationary state concentrated at scale ? and perturbation. rely on detailed spectral analysis linearised dynamics parabolic neighbourhood singularity performed by authors [10], providing refined expansion Our main result constru...