Context. The BL Lac object 1ES 0647+250 is one of the few distant γ-ray emitting blazars detected at very high energies (VHEs; ≳100 GeV) during a non-flaring...
Long-term multi-wavelength variability and correlation study of Markarian 421 from 2007 to 2009
Aims: We study the multi-band variability and correlations of the TeV blazar Mrk 421 on year timescales, which can bring additional insight on the processes...
Long-term optical spectral monitoring of a changing-look active galactic nucleus NGC 3516. II. Broad-line profile variability
Context. We analyze the broad Hβ line profile variability of a "changing look" active galactic nucleus (CL-AGN) NGC 3516 over an extensive period of 25 years...
Long-term photometric monitoring with the Mercator telescope. Frequencies and multicolour amplitudes of γ Doradus stars
Context: γ Dor stars are excellent targets for asteroseismology since the gravity modes present in these stars probe the deep stellar interiors. Mode...
Long-term photometry of WX Arietis: evidence for eclipses and dips
We present R-band photometry of the SW Sex-type cataclysmic variable WX Arietis made in October 1995 and August 1998-February 1999. Contrary to previous results...
Long-term stability of spotted regions and the activity-induced Rossiter-McLaughlin effect on V889 Herculis. A synergy of photometry, radial velocity measurements, and Doppler imaging
Context: The young active G-dwarf star V889 Herculis (HD 171488) shows pronounced spots in Doppler images as well as large variations in photometry and radial...
Looking into the faintEst WIth MUSE (LEWIS): Exploring the nature of ultra-diffuse galaxies in the Hydra-I cluster. I. Project description and preliminary results
Looking into the faintEst WIth MUSE (LEWIS) is an ESO large observing programme that aims at obtaining the first homogeneous integral-field spectroscopic survey...
Low deuterium abundance in the z_abs=3.514 absorber towards APM 08279+5255
{A high-resolution, high signal-to-noise HIRES-Keck spectrum of APM 08279+5255 reveals a feature in the HI Lyalpha profile of the z_abs=3.514 absorber at the...
Low Resolution Mapping of Comet p/ Halley in the Near Infrared
We present low resolution maps, of a 4' × 0'.5 region, of comet Halley, in photometric bands J and K, a central scan in the H band and JHKL photometry taken...