ESO DOI Service

• Beccari, Giacomo [European Southern Observatory (ESO)]
• Petr-Gotzens, Monika G. [European Southern Observatory (ESO)]
• Boffin, Henri M. J. [European Southern Observatory (ESO)]
• Jerabkova, Tereza [European Southern Observatory (ESO)]
• Romaniello, Martino [European Southern Observatory (ESO)]
• Areal, María Belén [CONICET–Universidad de Buenos Aires, Instituto de Astronomía y Física del Espacio, Argentina]
• Carraro, Giovanni [Dipartimento di Fisica e Astronomia Galileo Galilei, Padova, Italy]
• Celis, Mariela [CONICET–Universidad de Buenos Aires, Instituto de Astronomía y Física del Espacio, Argentina]
• De Marchi, Guido De [ESTEC, Noordwijk, the Netherlands]
• de Wit, Willem-Jan [European Southern Observatory (ESO)]
• Drew, Janet E. [Centre for Astrophysics Research, STRI, University of Hertfordshire, Hatfield, UK]
• Fedele, Davide [INAF–Osservatorio Astrofisico di Arcetri, Firenze, Italy]
• Ferrero, Leticia V. [CONICET–Universidad de Buenos Aires, Instituto de Astronomía y Física del Espacio, Argentina]
• Kalari, Venu M. [Departamento de Astronomía, Universidad de Chile, Santiago, Chile]
• Manara, Carlo F. [European Southern Observatory (ESO)]
• Mardones, Diego [Departamento de Astronomía, Universidad de Chile, Santiago, Chile]
• Martin, Eduardo L. [CSIC-INTA Centro de Astrobiologia, Madrid, Spain]
• Meza, Erick [LESIA/Observatoire de Paris, CNRS UMR 8109, Université Pierre et Marie Curie, Université Paris-Diderot, Meudon, France]
• Mieske, Steffen [European Southern Observatory (ESO)]
• Panagia, Nino [Space Telescope Science Institute, Baltimore, USA]
• Testi, Leonardo [European Southern Observatory (ESO)]
• Vink, Jorick S. [Armagh Observatory, UK]
• Walsh, Jeremy R. [European Southern Observatory (ESO)]
• Wright, Nick J. [Astrophysics Group, Keele University, UK]

We present the first results of the Accretion Discs in Hα with OmegaCAM (ADHOC) survey, which aims to perform a deep and homogeneous photometric study of pre-main sequence (PMS) stars in a number of nearby star-forming regions. We took advantage of the exquisite image quality and wide-field capabilities of OmegaCAM at the VLT Survey Telescope (VST) to perform multi-band (ugri and Hα), deep (i_SDSS < 22 mag), homogeneous and wide-field (covering tens of parsecs) observations of eight star-forming regions: the Orion Nebula Cluster, Lupus, Sco-Cen, Haffner 18, Vela OB2, Eta Cha, Chamaeleon and Ophiuchus. Using a robust method to identify PMS stars through their photometric excess in the Hα band, we aim to measure physical parameters (including mass accretion rates) for over 10 000 PMS stars. Direct comparison with low-resolution spectroscopy confirms that the objects with Hα excess emission that are detected photometrically are bona-fide PMS stars. The first results from this study clearly demonstrate the validity of the observational approach to unveiling complex stellar populations in young clusters.