Johannes Andersen     

Personal data:

     Name: Johannes Andersen
    Title: Associate Professor emeritus 
     Born: 29 August 1943

      Fax: +45 3532 5989
    Phone: +45 3532 5934
Secretary: +45 3532 5999
  Private: +45 5943 8982

Job description:

My job description at the NBI includes research and liaison tasks to promote the scientific returns of the Danish membership in international astronomical organisations.

For the period 2002-2013, I served as Director of the Nordic Optical Telescope on La Palma, Canary Islands, Spain.

A brief formal CV can be found here, and an (incomplete) publication list here.

Current activities are briefly summarised as follows:

Research projects

Numbers in my publication list are given for reference.
  • Following earlier instrumentation projects, I served 1996-2002 as responsible for the instrument center IJAF (now IDA), which equipped the Danish 1.5m telescope at ESO and the NOT with state-of-the-art CCD and near-IR cameras (171, 198, 237, 241).
  • My main current astronomical research focuses on observational studies of the chemical and dynamical evolution of the disk of the Milky Way Galaxy. Following an earlier, detailed spectroscopic study (158), we are currently analysing new, accurate data on ages, metallicities, and kinematics of some 10.000 nearby F and G dwarfs (165, 190, 197), including the connection between their past and present galactic orbits (195). The culminating paper (279) is now being followed up by a review and verification of the main calibrations and associated results (328, 346). As part of this effort, we have also determined radial velocities for some 25.000 late-type HIPPARCOS stars.
  • In a part of the project devoted to the most metal-poor - hence presumably oldest - halo stars in the Galaxy, we have been awarded a large Programme at the ESO Very Large Telescope and UVES spectrograph in 2000-2001. A first, interesting result on an age determination for one of these old stars using radioactive uranium-238 and thorium-232 is published in (244). A series of papers describing the results of the systematic programme has followed (259, 263, 268, 277, 278, 290, 301, 303, 320, 329, 331, 345, 355, 356, 361).
  • A second, connected, primary interest for many years is the observational study of stellar evolution, especially the reliability of stellar ages. A long program to determine and analyse accurate stellar masses and radii in eclipsing binaries, summarised in (140, 146, 177, 198, 232 and most recently in 350). This was supplemented by a study of a few open clusters, where again sufficiently detailed work led to firm conclusions on the stellar models - and considerable surprises regarding the dynamical state of these "standard" clusters (196, 216, 234).
  • Two sidelines of this research were the dynamics and binary frequency of globular clusters (67, 186), and a study of some potentially significant pre-main-sequence binaries (124, 134, 199, 207).
  • In return for a Danish investment in the French EROS microlensing project at La Silla, we are sharing in some of the corresponding publications, e.g. (211, 212, 219, 220, 233, 239) - including the culminating ones (322, 343), which showed that planet- and star-like baryonic objects constitute a negligible fraction of the dark Galactic halo.
  • Following an earlier low-level foray into the search for extrasolar planets (170, 184), I am starting a participation in the ground-based follow-up of transiting extrasolar planets discovered with the NASA Kepler Mission and from ground-based surveys, together with postdoc Lars Buchhave and the exoplanet group at the Harvard-Smithsonian Center for Astrophysics (353, 354, 357).
  • As part of these projects, I spent the year 1970-71 in Marseille, 1971-72 at the DAO, Victoria, 1986-89 at the Harvard-Smithsonian Center for Astrophysics, and September-December 2000 at Observatoire de Paris.

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    Last updated 25-06-2011 at 14.35 by