Uffe Gråe Jørgensen


Personal data:

     Name: Uffe Gråe Jørgensen
    Title: associate professor (Danish "lektor")

    Email: uffegj@nbi.dk
      Fax: +45 3532 5989
    Phone: +45 3532 5998
Secretary: +45 3532 5996

    The postal address of the institute is:
    Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, 2100 Copenhagen, Denmark
    The building was originally donated by the Rockefeller Foundation, and is therefore called 
    the Rockefeller Complex ("Rockefeller Komplekset").
    You will get a map of the area with  "Rockefeller_Komplekset"  marked on the map by clicking here.
    My office is room 037, at the ground floor of the building to the left after entering the main entrance.


Research:

My main areas of research are:

(1) Extrasolar planets (exoplanets) Since 2002 I have been involved in the search for extrasolar planets by use of the microlensing technique, as part of the international team PLANET . Our most recent result is the discovery of the first Earth-like exoplanet ever seen. Although the planet is far from identical to the Earth (for one it is estimated to have a surface temperature of -200 Celcius degrees), it is Earth-like in the sense of having a mass (5.5 Earth-masses) and an orbit (2.6 AU) much more resembling the Earth than any exoplanets ever observed before, and by being the only of the known exoplanets which might have formed and eveloved in the same way as the terrestrial planets in our own solar system (see below). The printed version of the paper describing the first results of the discovery, can be forund in Nature, vol.439, p.437-440. If your login allows it, the paper can be downloaded from Nature's homepage (otherwise use the ads-link above to retrieve a re-print) together with Nature's comments to the discovery on page 400-401 in the same issue of the journal. A short press-release animation made by ESO can be viewed here.
Other recent papers related to the work on microlensing by our team, include 1 , 2 , 3 , 4 , 5 , 6 , 7 .

(2) Late stages of stellar evolution. This has included research about
(1)red giant stars, (e.g., chemical abundances in Galactic halo stars , the formation of poly aromatic hydrocarbon clusters, PAH , and effects of mass loss on stellar evolution),
(2) white dwarfs ,
(3) globular clusters and the age of the universe, (e.g., results , and the method ),
(4) stellar populations in other galaxies (e.g., the Fornax Dwarf galaxy , population synthesis by use of the Ca IR triplet , and the UV radiation in metal-rich galaxies ) and
(5) other aspects of the final stages of evolution of normal stars (e.g., the final evolution of the Sun )

(3) The atmospheres of late-type stars, planets, brown dwarfs, and other plasmas where molecular absorption plays a role. Most of the work I have done in the field of modeling and simulations of cool gasses, is done with the MARCS stellar atmospheric code. A review of the atmospheric modelling was given in late 1994 in Astr.Astrophys.Rev.. My major contributions to the development of the atmospheric modelling technique includes
(1) effects and compuitations in spherical geometry ,
(2) the sampling technique ( 1992 , 1998 ),
(3) the role of molecular opacities ,
(4) the role of hydrodynamics (e.g., A&A 1999 and A&A 1998 ),
(5) testing the models against spectral observations from space (e.g., our ISO_spectra of carbon stars), and from the ground (e.g., complete AGB carbon star spectra from 5000 AA to 2.5 mu_m, and high-resolution SiO_spectra of M-type giants).

A major obstacle for progress in this field has during a few decades been the lack of input data for the modelling. A substantial part of my effort in the field has therefore been to perform quantum mechanical computations of molecular line lists and other crucial input data. A review of the data base that has been one outcome of this work was described in a review paper at IAU Symposium 178. A describtion of the quantum mechanical methods we have been using was given in our first papers on the absorption coefficient of HCN and C3 . A recent paper in the work of constructing a molecular opacity data base is the calculation of the absorption coefficient for water . See also the separate description of the SCAN molecular data base below.

(4) The formation and evolution of the solar system. My contribution to this field has mainly been concerning the origin of the material which the solar system is made of. We have extracted extrasolar diamonds and silicon_carbide grains from carbonaceous chondrite meteorites and measured their optical properties. By including these data in atmospheric modelling it is in principle possible to trace the stellar origin of the material that became the solar system. My original ideas about origin of the meteoritic extrasolar diamond (and SiC) dust in carbon stars were presented in paper in Nature in 1988. A recent description of our ideas about the stellar-meteoritic connection was presented at IAU Symposium 177.
I have also contributed to the solar system research with preditions and speculations about what will happen to the Sun and the Earth during the final phases of the evolution of the Sun (a short proceeding and a longer A&A paper, emphasizing different aspects), and with aspecta of the formation of the solar nebula and the formation of the Earth and its oceans (work in preparation).


The SCAN molecular data base:

C2
Information

CH
Information
Paper

CN
Paper

H2O
Line list
Information
Paper

SiO
Line list

TiO
Line list
Information
Paper


Teaching:

Courses I am teaching:

I am for the moment teaching two graduate courses ("Planetary Physics" and "Astrobiology"), and two bachelor courses ("Stellar and planetary formation, the solar system" and "Stellar astrophysics and radiative transfer".
In the autumn (block 1) of 2005, I taught a graduate course on Astrobiology "Astrobiology" about the formation of the elements in Big Bang and in stars, the origin of the solar system and the Earth, and the origin and evolution of life and the search for it outside the Earth. This course will be given again in the autumn of 2007.
As an off-spring of the course, we had some years ago a study-circly (studiekreds) on "The role of comets for the early Earth".
Since some years we have had a closer collaboration between people at NBI and other institutions in Copenhagen who are interested in aspects of the solar system, and we are given several courses. At NBI we are given a two block graduate course together every second year. The content of the course change somewhat from time to time, but in block 3 and 4 (i.e. the spring semester) of 2005 it consisted of a traditional course with lectures and exercises etc in block 3 ("The Physics of the Solar System". ) followed by a course based on larger numerical problems in block 4.

Thesis supervision:

I am presently supervisor for:
Christian Vinter who is writing his Ph.D. Thesis on the search for exoplanets by use of the microlensing technique,
Sitte Larsson who is writing her Master Thesis on the formation of the solar system with particular emphasis on the molecule and dust formation in the collapsing disk,
Kristian Woller who is writing his Master Thesis on the search for exoplanets by use of the microlensing technique,
Tobias Hinse who is writing his Master Thesis on orbital computation (resonances, migration, etc) of exoplanets.
I am co-supervisor for:
Juliana daSilva (co-advising with Luiz Paul Vaz, Bel Horizonte, Brazil) who is writing her Ph.D. Thesis about radiative transfer and external illumination in stellar and exoplanetary atmospherers,
Stefan Wolf (co-advising with Poul Hjort, Danish Technical University) who is writing his Ph.D. Thesis about Near-Earth asteroids, in particular the planning of observations of these with the coming Gaia satellite.
Previous Master and PhD students:
Anja Andersen, Christiane Helling, Raul Jimenez, Jens Falkesgaard, Søren Rasmussen, and Peter Pedersen. Dorte E. Rasmussen (who wrot her Master Thesis on cool white dwarfs), Steen E. Jørgensen (who wrot his Master Thesis about laser communication with satellites, in particular concerning Bering and near-Earth asteroids; co-advising with Flemming Hansen, DSRI)

Suggestions for B-colloquia (hovedfags colloquia):

Graduate students af NBI are required as a part of their studies to present an institute colloquium on a chosen subject. If you are a student at NBI and are looking for a subject to present, you can find my suggestions by clicking at topics here.

Suggestions for Thesis projects (specialer):

If you are a student at NBI looking for an idea for a Thesis project you can find some suggestions for projects here which I can advice you in.


Popularization:

Since 1995, Bent Raymond Jørgensen and I have usually arranged a series of public lectures in at NBI, Blegdamsvej, covering a broad range of natural science, history of science, and philosophy. The series at NBI was filmed and broadcated in Danish television (DR1 in 1995), and later we made a technically better version in the television studios which was broadcasted in 1996/97 (a total of 25 broadcastings).
The series of lectures was issued in the form of a book with the titel "Videnskaben_eller_Gud?", ("Science or God?") in 1996, with a revised second edition in 1998 and revised and enlarged third edition in 2005. Bent's sister Connie has made an impressive presentation of the book which you can see by clicking above, and with the appropriate equipment on your computer, you can even listen to pieces of each of the chapters from her home page. The book was published by DR Multimedie, and the third edition is available from bookstores for 349,- kr. The series of public lectures are usually in aud A at NBI Blegdamsvej during the autumn, and tickets can be bought from FOF, Copenhagen. !talks from 2001 can be found here. !talks for 2002 can be found here.


I regularly publish popular articles in various journals, recently:
Naturens Verden about Tycho Brahe (NV, vol.84, nr.10, p26-31)
Naturens Verden about the origin or the Earth's oceans (NV, vol.85, nr.2, p2-13),
Aktuel Astronomi about exoplanets (AA, 2004 nr 2, p.16-19),
Kvant about the formation of solar systems (vol.15 nr.3, 2004, p.8-14),
Kvant about the Deep Impact collision with Comet Tempel (vol.16 nr.3, 2005, p.11,12,36),
Universitetets Almanak 2006 about exoplanets (2006).


ESO users committee:

Danish users of the ESO facilities are kindly requested to fill in the following questionary before Marts 16, 2006. I will summarize the results and present them at the ESO Users Committee meeting in Garching on April 2, together with other comments I have got from the Danish comunity regarding ESO. My deadline for sending the summary to ESO is Marts 20, in order that it can be included in the material that is distributed to the ESO UC before the meeting. You can also write an email to me with your comments instead (at uffegj@nbi.dk).
Last updated Marts 2006 by uffegj@nbi.dk.