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We here present the ages of four compact stellar clusters (CSCs) in the nearby spiral galaxy M81, using long-slit optical spectra obtained with the 10.4-m Gran Telescopio Canarias (GTC). All the four CSCs, including the brightest in this galaxy, are found to have ages between 5 to 6 Myr, with one of them showing Wolf-Rayet spectral features. The photometric masses of these clusters, calculated using their spectroscopically-derived ages, lie between 3000 and 18000 Msun. The observed clusters are among the brightest objects, and hence the most massive, in the entire disk of M81. This implies the absence of massive (1.0e5 Msun) compact stellar clusters in M81.
We obtained spectra of 74 globular clusters in M81. These globular clusters had been identified as candidates in an HST ACS I-band survey. 68 of these 74 clusters lie within 7 of the M81 nucleus. 62 of these clusters are newly spectroscopically confi
We present two transits of the hot-Jupiter exoplanet XO-2b using the Gran Telescopio Canarias (GTC). The time series observations were performed using long-slit spectroscopy of XO-2 and a nearby reference star with the OSIRIS instrument, enabling dif
We study the population of compact stellar clusters (CSCs) in M81, using the HST/ACS images in the filters F435W, F606W and F814W covering, for the first time, the entire optical extent of the galaxy. Our sample contains 435 clusters of FWHM less tha
HH 223 is a knotty, wiggling nebular emission of ~30 length found in the L723 star-forming region. It lies projected onto the largest blueshifted lobe of the cuadrupolar CO outflow powered by a low-mass YSO system embedded in the core of L723. We ana
We perform aperture photometry and profile fitting on 419 globular cluster (GC) candidates with mV leq 23 mag identified in Hubble Space Telescope Advanced Camera for Surveys BVI imaging, and estimate the effective radii of the clusters. We identify