A T N F    D a i l y    A s t r o n o m y    P i c t u r e

16th of October 2015
CHANG-ES astronomers probe the spectacular halos of galaxies
by Jayanne English (University of Manitoba, Canada)
The CHANG-ES collaboration has recently made their first batch of specialized Very Large Array maps for 35 edge-on galaxies available to other researchers at http://queensu.ca/changes. Led by Judith Irwin (Queen's U., Canada), the team studies the radio halo produced by fast-moving particles in a galaxy's magnetic field. In a companion paper, led by Theresa Weigert, they present a 'median radio halo'. That is, to see how extensive a "typical" halo is, Irwin scaled radio continuum observations of 30 of their target galaxies and Jayanne English (U. Manitoba) combined them using a median algorithm. The individual halos were acquired at 20 cm using the Very Large Array (VLA) in the D configuration. - A press release is available at NRAO.

In the composite image presented here, the large, grey-blue area is a single image of this median radio halo. As a proxy for a generic spiral galaxy disk, at the center is a visible-light image of one of the target galaxies -- NGC 5775. Made from data acquired in 2 filters using the Hubble Space Telescope, this visible-light image shows only the inner part of the galaxy's star-forming region, outer portions of which extend horizontally into the area of the radio halo.

Image credit: Jayanne English (U. Manitoba), with support from Judith Irwin and Theresa Wiegert (Queen's U.) for the CHANG-ES consortium; NRAO/AUI/NSF; NASA/STScI

<<   |   archive   |   about   |   today   *   ATNF   |   Parkes   |   ATCA   |   Mopra   |   VLBI   |   ASKAP   |   >>