The 1.5-meter GREGOR solar telescope is a new facility for high-resolution observations of the Sun. The telescope is located at the Spanish Observatorio del Teide on Tenerife. The telescope incorporates advanced designs for a foldable-tent dome, an open steel-truss telescope structure, and active and passive means to minimize telescope and mirror

We present the GTC data processing subsystem, hereinafter ``Data Factory''. The main objectives, functionality and overall philosophy are described. We also briefly outlay the architectural description of the Data Factory and its organization. The current state of development is also presented as well as some real reduction examples.

We present the online and the offline data reduction system for OSIRIS, the optical multi-mode instrument for GranTeCan. The software is written in Python and invokes PyRAF tasks which have been optimized for the instrument. We review the characteristics of the instrument and of the software. We will also present the improvements which are foreseen

It has recently been shown that the correct halo mass function high-mass behavior may be obtained by an appropriate treatment of the all-mass-at-center problem. Here we show that the treatment of this problem leads to an accumulated mass fraction, F, that is not a universal function of the linear variance of the density contrast but depends on the

A large set of high precision full-Stokes spectro-polarimetric observations of the He I D3 line in spicules has been recorded with the ZIMPOL polarimeter at the Gregory-Coudé Telescope in Locarno. The observational technique allows us to obtain measurements free from seeing-induced spurious effects. The instrumental polarization is well under

We present a theoretical investigation on the influence of the magnetic field on the linear and circular polarization of the Ba II D2 line at 4554 Å, through the Hanle and Zeeman effects. We show in particular the existence of a differential magnetic sensitivity of the three-peak structure of the Q/I profile observed for this line, which is of