CORDIS - Résultats de la recherche de l’UE
CORDIS

New Science enabled with the Expanded Very Large Array

Final Report Summary - NEWEVLA (New Science enabled with the Expanded Very Large Array)

The expansion project of the Very Large Array (VLA) near Socorro was a dramatic upgrade of one of the most successful scientific instruments. The new Expanded VLA is now a completely new instrument and orders of magnitude more powerful than the old VLA. Until recently, the commissioning of the EVLA was under progress, and the new capabilities were already available only to researchers who spend time in Socorro to assist with the commissioning. This put European researchers at risk to lose their competitiveness compared to colleagues in the US, who can be personally present in Socorro. By going directly to Socorro I could avoid this problem, since I could use the full capabilities of the EVLA early on.

The central aims of this proposal were to
a) become a leading expert in Europe on the EVLA by hands-on experience in the commissioning phase,
b) initiate ground-breaking new science currently not possible from anywhere in Europe by using the full capabilities of the new EVLA, and
c) bring this new knowledge back to my host institute in Europe, the Max-Planck-Institut fuer Radioastronomie (MPIfR) in Bonn.

I pursued three different scientific projects, which have a large potential for a significant impact. The first project is related to the diversity of radio Supernovae. In particular, the supernova 2011dh in M51 has been observed with the EVLA and VLBI. The results have been published already in four papers.
The second project was initially a parallax measurement of the ultracompact binary HMCnc. However, the source could not be detected again after the initial detection. Hence, it was not possible to measure a parallax. Instead, I observed the two local group galaxies M33 and NGC6822 in deep polarized radio continuum and several spectral lines (6.7 GHz methanol masers and radio recombination lines). These projects were observed during the first year of the IOF. Since the data sets for these types of combined continuum and spectral line observations are one to two orders of magnitude larger than and previous VLA data sets, the analysis is complex and still ongoing. Nonetheless some of the findings could already be published in three papers.
Finally, I started to measure the proper motion of the Andromeda galaxy. This is essential for our understanding of the evolution of the Local Group, which is an important laboratory to test theories of gravity. First, the EVLA was used to determine sub-arcsecond positions of the water masers, and a first VLBI observation was conducted in February 2012. Two of the water masers were easily detected and each has been observed four times during the winter 2012/2013. More observations for these maser sources will be conducted during the next two winter periods. This enables us to get a more accurate proper motion of Andromeda as well as an accurate geometric distance (rotational parallax).
During my outgoing phase, I gained a lot of experience with the enhanced capabilities of the VLA as part of my commissioning effort. This knowledge benefits other projects conducted at my return host organization, and lead to new collaborations on several projects with other institutes within Europe. Within my transfer of knowledge activities I was involved in two more papers.