Olaf Wucknitz



These pages are updated on an irregular basis. If you are looking for more up to date information about my work, ask me directly. The list of publications should be more reliable than the rest, though...

Note that I am now at the MPIfR. The AIfA email will still work for some time, but the office address has changed.


Emmy-Noether research group

I am the head of a small research group working in the field of "Radio lenses" at the Argelander-Institut für Astronomie, Universität Bonn. This project is funded by the German Science Foundation (DFG) in the Emmy-Noether programme.


LOFAR goes multinational!

In January 2011, LOFAR stations in the Netherlands, Germany, France and the UK were combined for the first time to produce multi-national fringes and images. The first target of these low-frequency VLBI observations was the quasar 3C196. The data were analysed and mapped by Olaf Wucknitz, Bonn.

3C196 with Dutch LOFAR stations 3C196 with international LOFAR stations

The first image above shows the field of 3C196 imaged with stations in the Netherlands only. The resolution of about 11 arcsec is not sufficient to resolve any details. By including international stations in Tautenburg (Germany), Nancay (France) and Chilbolton (UK) in the second image, the resolution is improved by a factor of 30 (0.35 arcsec) so that we can not only distinguish the two compact components with 5.5 arcsec separation but even resolve structures within each of them. LOFAR is finally entering true sub-arcsec territory.
12 h of observing time with 1/4 of the full bandwidth covering the range 120-165 MHz were used to produce these images. By observing at even higher frequencies, the resolution can be improved by another factor of 2.

See press releases of ASTRON (or in Dutch), STFC (UK), Nancay Observatory (in French), Onsala Space Observatory (in Swedish).

At lower frequencies (30-80 MHz), the source was already resolved in 2010 using stations in the Netherlands and Germany:

first
long-baseline maps of 3C196

Only the rather compact upper and lower components can be seen in the high-resolution version shown before.

For more details of these previous results, see press releases of the MPIfR (or the German version), the Thüringer Landessternwarte Tautenburg (in German), the MPA (or the German version), ASTRON, or the ASTRON/JIVE Daily Image of 1st June 2010.


Wiki

Radio lenses

LOFAR LBG (long baseline group)


Research

Gravitational lensing

Relativity

Radio interferometry

LOFAR

Optical image deconvolution

Comet Hale-Bopp

Usually my list of publications is more up to date than these overviews of research topics. For projects not yet published in refereed journals (quite many actually), please also consult the list of conference contributions and seminars and colloquia.


Publications

(including refereed journals, theses, conferences & workshops, seminars & colloquia, lectures, popular & public talks, other reports, talks, etc and preprints)


Teaching

(lectures partly with presentations and supplementary material)


JENAM 2009 Gravitational Lensing Symposium

The symposium Three decades of gravitational lenses at JENAM 2009 was dedicated to the memory of Sjur Refsdal, 1935-2009. Most presentations are available here.

Address

Max-Planck-Institut für Radioastronomie (MPIfR)
Auf dem Hügel 69
53121 Bonn
Germany
Phone:   +49-(0)228-525-481

e-mail:  wucknitz(at)mpifr-bonn.mpg.de

Secondary affiliation

Argelander-Institut für Astronomie (AIfA)
Universität Bonn
Auf dem Hügel 71
53121 Bonn
Germany
e-mail:  wucknitz(at)astro.uni-bonn.de


Former affiliations:
Joint Institute for VLBI in Europe (JIVE)
Astrophysics branch of the physics department of Potsdam University
Jodrell Bank Observatory
Hamburger Sternwarte

To the AIfA
To the University of Bonn


This document last modified Fri Sep 7 15:21:58 CEST 2012