Constraining the wind launching region in Herbig Ae stars: AMBER/VLTI spectroscopy of HD 104237 ^*

¹ INAF-Osservatorio Astrofisico di Arcetri, Istituto Nazionale di Astrofisica, Largo E. Fermi 5, 50125 Firenze, Italy
² Dipartimento di Fisica, Università degli Studi di Milano, Via Celoria 16, 20133 Milano, Italy
³ Laboratoire d'Astrophysique de Grenoble, UMR 5571 Université Joseph Fourier/CNRS, BP 53, 38041 Grenoble Cedex 9, France
⁴ Laboratoire Gemini, UMR 6203 Observatoire de la Côte d'Azur/CNRS, BP 4229, 06304 Nice Cedex 4, France
⁵ Laboratoire Universitaire d'Astrophysique de Nice, UMR 6525 Université de Nice – Sophia Antipolis/CNRS, Parc Valrose, 06108 Nice Cedex 2, France
⁶ Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany
⁷ European Southern Observatory, Casilla 19001, Santiago 19, Chile
⁸ Instituut voor Sterrenkunde, KU-Leuven, Celestijnenlaan 200D, 3001 Leuven, Belgium
⁹ ONERA/DOTA, 29 av de la Division Leclerc, BP 72, 92322 Chatillon cedex, France
¹⁰ Centre de Recherche Astronomique de Lyon, UMR 5574 Université Claude Bernard/CNRS, 9 avenue Charles André, 69561 Saint Genis Laval Cedex, France
¹¹ Centro de Astrofísica da Universidade do Porto, Rua das Estrelas, 4150-762 Porto, Portugal
¹² Division Technique INSU/CNRS UPS 855, 1 place Aristide Briand, 92195 Meudon Cedex, France
¹³ Laboratoire Astrophysique de Toulouse, UMR 5572 Université Paul Sabatier/CNRS, BP 826, 65008 Tarbes Cedex, France
¹⁴ IRCOM, UMR 6615 Université de Limoges/CNRS, 123 avenue Albert Thomas, 87060 Limoges Cedex, France
¹⁵ European Southern Observatory, Karl Schwarzschild Strasse 2, 85748 Garching, Germany
¹⁶ Kiepenheuer Institut für Sonnenphysik, Schöneckstr. 6, 79104 Freiburg, Germany
¹⁷ Departamento de Astronomia, Universidad de Chile, Chile

Received: 29 May 2006
Accepted: 26 June 2006

Abstract

Aims.We investigate the origin of the  emission of the Herbig Ae star HD 104237 on Astronomical Unit (AU) scales.

Methods.Using AMBER/VLTI at a spectral resolution we spatially resolve the emission in both the  line and the adjacent continuum.

Results.The visibility does not vary between the continuum and the  line, even though the line is strongly detected in the spectrum, with a peak intensity 35% above the continuum. This demonstrates that the line and continuum emission have similar size scales. We assume that the K-band continuum excess originates in a “puffed-up” inner rim of the circumstellar disk, and discuss the likely origin of .

Conclusions.We conclude that this emission most likely arises from a compact disk wind, launched from a region 0.2–0.5 AU from the star, with a spatial extent similar to that of the near infrared continuum emission region, i.e., very close to the inner rim location.