High-speed photometric observations were performed of the Ap stars HD62140 (49 Cam), HD81009, and HD22374 for more than 60 hr in Oct. and Dec. 1986. Photometric measurements in the B band were reduced and the residuals obtained were subjected to a harmonic analysis, searching for periodicities in the range of a few minutes to 2 hr. There is

A new approach to the study of the large-scale stellar cluster distribution in the Galaxy based on two-point correlation techniques is presented. The basic formalism for this method is outlined, and its applications are then investigated by the use of a simple model of cluster distribution in the Galaxy. This provides an estimate of the potentials

A search for physics beyond the standard model in final states with at least one photon, large transverse momentum imbalance, and large total transverse event activity is presented. Such topologies can be produced in gauge-mediated supersymmetry models in which pair-produced gluinos or squarks decay to photons and gravitinos via short-lived

The microquasar Cygnus X-1 displays the two typical soft and hard X-ray states of a black hole transient. During the latter, Cygnus X-1 shows a one-sided relativistic radio-jet. Recent detection of the system in the high energy (HE; E ≳ 60 MeV) gamma-ray range with Fermi-LAT associates this emission with the outflow. Former MAGIC observations

Context. The total mass of a cluster, which is the main parameter determining its ability to host more than one stellar generation, may constitute a threshold below which the cluster is able to form only a single stellar population. Aims: Our goal is to investigate the existence of star-to-star variations in CN and CH band strengths, which are

Distant clusters of galaxies provide a powerful method to study the formation and evolution of galaxies, and large scale structure of the Universe. However, the number of known clusters at high redshift (z > 0.5) is still very reduced. As a preparatory work for detailed studies with GTC, we are searching for high redshift clusters in public wide