Multi-Conjugate Adaptive Optics images of the Trapezium Cluster ⋆

Context. Multi-conjugate adaptive optics (MCAO) combine the advantages of both standard adaptive optics, which provide high contrast and high spatial resolution, and of wide field imaging (≈1 � ). Up to recently, MCAO for astronomy was limited to laboratory experiments. In this paper, we present the first scientific results obtained with the first MCAO instrument. Aims. We present a new study of the Trapezium cluster using deep MCAO images with a field of view of 1 � × 1 � obtained at the VLT. Methods. We used deep J, H ,a ndKs images recently obtained with the prototype MCAO facility MAD at the VLT to search for new members and new multiple systems in the Trapezium cluster. On bright targets (Ks ≈ 9 mag), these images allow us to reach ∆Ks ≈ 6 mag as close as 0 . �� 4.

[1]  C. O’Dell.  New Proplyds, Outflows, Shocks, and a Reflection Nebula in M43 and the Outer Parts of the Orion Nebula , 2001 .

[2]  Mark E. Ealey.  Active and adaptive optical systems , 1991 .

[3]  Portugal,et al.  Size distribution of circumstellar disks in the Trapezium cluster , 2005, astro-ph/0506585.

[4]  Infrared L-Band Observations of the Trapezium Cluster: A Census of Circumstellar Disks and Candidate Protostars , 2000, astro-ph/0008280.

[5]  Lynne A. Hillenbrand,et al.  Constraints on the Stellar/Substellar Mass Function in the Inner Orion Nebula Cluster , 2000 .

[6]  Gerd Weigelt,et al.  Orbital motion of the massive multiple stars in the Orion Trapezium , 2003 .

[7]  Jun Jugaku,et al.  Star Forming Regions , 1987 .

[8]  J. Spyromilio,et al.  The European Extremely Large Telescope (E-ELT) , 2007 .

[9]  M. Fulchignoni,et al.  Demonstration of Adaptive Optics for Resolved Imagery of Solar System Objects: Preliminary Results on Pallas and Titan , 1993 .

[10]  F. Ochsenbein,et al.  The VizieR database of astronomical catalogues , 2000, astro-ph/0002122.

[11]  Michael W. Werner,et al.  HST photometry of the trapezium cluster , 1994 .

[12]  Roberto Ragazzoni,et al.  Adaptive-optics corrections available for the whole sky , 2000, Nature.

[13]  M. Ulrich.  Very large telescopes and their instrumentation. Proceedings. , 1988 .

[14]  Eduardo L. Martin,et al.  Multiplicity of Nearby Free-floating Ultracool Dwarfs: A Hubble Space Telescope WFPC2 Search for Companions , 2003, astro-ph/0305484.

[15]  Robert Q. Fugate,et al.  Adaptive Optical Systems and Applications , 1995 .

[16]  M. Tsujimoto,et al.  Chandra Orion Ultradeep Project: Observations and Source Lists , 2004, astro-ph/0410136.

[17]  John R. Stauffer,et al.  High resolution near-infrared imaging of the trapezium: A stellar census , 1994 .

[18]  The Luminosity and Mass Function of the Trapezium Cluster: From B Stars to the Deuterium-burning Limit , 2002, astro-ph/0203122.

[19]  Laird M. Close,et al.  Adaptive Optics Imaging of the Orion Trapezium Cluster , 1999 .

[20]  C. O’Dell,et al.  Hubble Space Telescope Mapping of the Orion Nebula. I. A Survey of Stars and Compact Objects , 1996 .

[21]  Andrea Richichi,et al.  Binary Stars in the Orion Trapezium Cluster Core , 1998 .

[22]  M. Bertero,et al.  The Orion Nebula in the Mid-Infrared , 2004, astro-ph/0412665.

[23]  Thermal Dust Emission from Proplyds, Unresolved Disks, and Shocks in the Orion Nebula , 2005, astro-ph/0506445.

[24]  The initial mass function of low-mass stars and brown dwarfs in young clusters , 2000, astro-ph/0004386.