Our Research

Parkes RRL survey

RRL image
The Parkes radio telescope undertook a large survey of HI, called the HI-Parkes-All-Sky-Survey (HIPASS), which focussed on detecting HI emission from galaxies. We have re-analysed this large data set, including data from the Zone of Avoidance (ZOA) survey, to extract 3 radio recombination lines (RRLs) that happen to lie in the passband of the receiver: these are the H166-168alpha lines.
Early results of this analysis are published in Alves et al. (2010) and Alves et al. (2012). The final Galactic plane survey, covering longitudes 248-0-52 degrees is now available for download below. The data reduction and analysis is described in Alves et al. (2015, MNRAS, 450, 2025). The image above shows the integrated RRL intensity map covering a large area of the Galactic plane.

RRL_H166-167-168a_HIPASS+ZOA_FF.fits The free-free emission map in units of K brightness temperature at 1.4 GHz, estimated with an electron temperaure gradient with Galactocentric radius 496 K/kpc. [20MB]
RRL_H166-167-168a_HIPASS+ZOA_TE.fits Map of the electron temperature as estimated in our paper. This model was used to convert from RRL brightness to free-free emission at 1.4 GHz. [20MB]
RRL_H166-167-168a_HIPASS+ZOA_TLdv.fits The RRL integrated map in units of K km/s. [20MB]
RRL_H166-167-168a_HIPASS+ZOA_lbv.fits The RRL datacube covering the whole spatial extent of the survey (248 deg in longitude, 10 deg in latitude), with +/-335 km/s velocity coverage, spectral resolution 20 km/s, and channel width 13.4 km/s. The cube combines the 3 RRLs of H166-168alpha. The units are K brightness temperature with an rms noise per channel of 2.8 mK. [200MB]

If you have any questions, please contact Dr Marta Alves or Prof. Clive Dickinson.