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

K. Geißler, S. Kellner, W. Brandner, E. Masciadri, M. Hartung, T. Henning, R. Lenzen, L. Close, M. Endl, M. Kürster

Research output: Contribution to journalArticle

6 Scopus citations

Abstract

We have carried out a direct and differential imaging search for sub-stellar companions to ε 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 ε Indi A. No detection was achieved in the inner neighbourhood down to 53 MJ (5 σ confidence level) at a separation ≥0.4″(1.45 AU) and down to 21 M J 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)°. The photometry for the candidate companion yields mH = (16.45 ± 0.04) mag and mKs = (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.

Original languageEnglish (US)
Pages (from-to)665-668
Number of pages4
JournalAstronomy and astrophysics
Volume461
Issue number2
DOIs
StatePublished - Jan 1 2007

Keywords

  • Stars: fundamental parameters
  • Stars: low-mass, brown dwarfs

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Fingerprint Dive into the research topics of 'A direct and differential imaging search for sub-stellar companions to ε Indi A'. Together they form a unique fingerprint.

  • Cite this

    Geißler, K., Kellner, S., Brandner, W., Masciadri, E., Hartung, M., Henning, T., Lenzen, R., Close, L., Endl, M., & Kürster, M. (2007). A direct and differential imaging search for sub-stellar companions to ε Indi A. Astronomy and astrophysics, 461(2), 665-668. https://doi.org/10.1051/0004-6361:20065843