ASTRONOMY AND ASTROPHYSICS Evolution of the dust mass loss with luminosity along the giant branch of the globular cluster 47 Tuc Abstract. The present paper investigates the properties of the dust mass loss in stars populating the giant branch of the globular cluster 47 Tuc, by combining ISOCAM and DENIS data. Raster maps of 5 fields covering areas ranging from 4 × 4 to 15 × 15 arcmin 2 at diff...

The stellar population of the Milky Way bulge is thoroughly studied, with a plethora of measurements from virtually the full suite of instruments available to astronomers. It is thus perhaps surprising that alongside well-established results lies some substantial uncertainty in its star-formation history. Cosmological models predict the bulge to host the Galaxy’s oldest stars for [Fe/H] −1, and...

The mechanism for the basal targeting of the Miranda (Mira) complex during the asymmetric division of Drosophila neuroblasts (NBs) is yet to be fully understood. We have identified conserved Phosphotyrosyl phosphatase activator (PTPA) as a novel mediator for the basal localization of the Mira complex in larval brain NBs. In mutant Ptpa NBs, Mira remains cytoplasmic during early mitosis and its ...

Long Period Variable stars are ubiquitous among the bright red giant branch stars in NGC 5128. Mostly they are found to be brighter than the tip of the first ascent giant branch with magnitudes ranging from about K = 19 to K = 21.5. They have periods between 155 and 1000 days and K-band amplitudes between 0.1 and 2 mag, characteristic of semi-regular and Mira variables. We compare the colors, p...

We search for microvariability in a sample of 485 Mira variables with high quality I-band light curves from the second generation Optical Gravitational Lensing Experiment (OGLE-II). Rapid variations with amplitudes in the ∼0.2–1.1 mag range lasting hours to days were discovered in Hipparcos data by de Laverny et al. (1998). Our search is primarily sensitive to events with time-scales of ∼1 day,...

Context. This paper is a follow-up on the vast effort to collect radial velocity data for stars belonging to the Hipparcos survey. Aims. We aim at extending the orbital data available for binaries with M giant primaries. The data presented in this paper will be used in the companion papers of this series to (i) derive the binary frequency among M giants and compare it to that of K giants (Paper...

The period-luminosity relation (PLR) of Mira variable stars is an important tool to determine astronomical distances. common approach estimating the PLR a two-step procedure that first estimates periods and then runs linear regression magnitude on log period. When light curves are sparse noisy, accuracy period estimation decreases can suffer from aliasing effects. Some methods improve by incorp...

Twelve IRAS sources in the LMC with colours similar to those expected for dust-enshrounded AGB stars have been monitored in the infrared for 1880 days. The objects come from the list of Reid (1991). Nine of these objects are large amplitude variables with periods in the range 530 to 1295 days. The variability confirms their status as dust-enshrouded AGB stars. Combined with the results of Wood ...