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A direct and differential imaging search for sub-stellar companions to epsilon Indi A

K. Geissler·S. Kellner·W. Brandner·E. Masciadri·M. Hartung·T. Henning·R. Lenzen·L. Close·M. Endl·M. Kuerster
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Abstract

We have carried out a direct and differential imaging search for sub-stellar companions to eps Indi A using the adaptive optics system NACO at the ESO VLT. The observations were carried out in September 2004 with NACO/SDI as well as with NACO's S27 camera in the H and Ks filters. The SDI data cover an area of \~2.8" around eps Indi A. No detection was achieved in the inner neighbourhood down to 53 Mj (5 sigma confidence level) at a separation > 0.4" (1.45 AU) and down to 21 Mj for separations > 1.3" (4.7 AU). To cover a wider field of view, observations with the S27 camera and a coronagraphic mask were obtained. We detected a faint source at a separation of (7.3 +/- 0.1)" and a position angle of (302.9 +/- 0.8) degree. The photometry for the candidate companion yields m(H)=(16.45 +/- 0.04)mag and m(Ks) = (15.41 +/- 0.06)mag, respectively. Those magnitudes and the resulting color (H-Ks) = (1.04 +/- 0.07)mag fit best to a spectral type of L5 - L9.5 if it is bound. Observations done with HST/NICMOS by M. Endl have shown the source to be a background object.

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K. Geissler, S. Kellner, W. Brandner, E. Masciadri, M. Hartung, T. Henning, R. Lenzen, L. Close, M. Endl, M. Kuerster. 2006-11-10. A direct and differential imaging search for sub-stellar companions to epsilon Indi A. https://doi.org/10.1051/0004-6361%3A20065843

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