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arXiv · 0810.0341

Multi-Conjugate Adaptive Optics VLT imaging of the distant old open cluster FSR1415

Y. Momany·S. Ortolani·C. Bonatto·E. Bica·B. Barbuy
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Abstract

We employ the recently installed near infrared Multi-Conjugate Adaptive optics demonstrator (MAD) to determine basic properties of a newly identified, old and distant, Galactic open cluster (FSR1415). The MAD facility remarkably approaches the diffraction limit, reaching a resolution of 0.07 arcsec (in K), that is also uniform in a field of ~1.8 arcmin in diameter. The MAD facility provides photometry that is 50% complete at K~19. This corresponds to about ~2.5 mag below the cluster main sequence turn-off. This high quality data set allows us to derive an accurate heliocentric distance of ~8.6 kpc, a metallicity close to solar, and an age of ~2.5 Gyr. On the other hand, the deepness of the data allow us to reconstruct (completeness-corrected) mass functions indicating a relatively massive cluster, with a flat core MF. The VLT/MAD capabilities will therefore provide fundamental data in identifying/analyzing other faint and distant open clusters in the Galaxy III and IV quadrants.

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Y. Momany, S. Ortolani, C. Bonatto, E. Bica, B. Barbuy. 2008-10-02. Multi-Conjugate Adaptive Optics VLT imaging of the distant old open cluster FSR1415. https://doi.org/10.1111/j.1365-2966.2008.14019.x

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