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Using the AAOmega instrument of the Anglo-Australian Telescope, we have obtained medium-resolution near-infrared spectra of 10,500 stars in two-degree fields centered on the galactic globular clusters 47 Tuc, NGC 288, M12, M30 and M55. Radial velocities and equivalent widths of the infrared Ca II triplet lines have been determined to constrain cluster membership, which in turn has been used to study the angular extent of the clusters. From the analysis of 140-1000 member stars in each cluster, we do not find extended structures that go beyond the tidal radii. For three cluster we estimate a 1% upper limit of extra-tidal red giant branch stars. We detect systemic rotation in 47 Tuc and M55.
Wide-field deep gri images obtained with the Megacam of the Canada-France-Hawaii Telescope (CFHT) are used to investigate the spatial configuration of stars around five metal-poor globular cluster M15, M30, M53, NGC 5053, and NGC 5466, in a field-of-
We present some results of numerical simulations of a globular cluster orbiting in the central region of a triaxial galaxy on a set of loop orbits. Tails start forming after about a quarter of the globular cluster orbital period and develop, in most
In the last decade, observational studies have shown the existence of tidal streams in the outer part of many galactic globular clusters. The most striking examples of clusters with well defined tidal tails are represented by Palomar 5 and NGC 5466 (
We report the detection of a pair of degree-long tidal tails associated with the globular cluster Palomar 14, using images obtained at the CFHT. We reveal a power-law departure from a King profile at large distances to the cluster center. The density
We use photometry from the DECam Legacy Survey to detect candidate tidal tails extending ~5 deg on either side of the Palomar 13 globular cluster. The tails are aligned with the proper motion of Palomar 13 and are consistent with its old, metal-poor