Supplementary Material to:

An Introduction to Radio Astronomy

4th edition Cambridge University Press 2019   


We have taken the opportunity to:

·       Present colour images of radio telescopes, receiver hardware and astronomical objects

·       Add pedagogic material not included in the main text due to length limitations

·       Add new short sections

o   Prologue (start of Chapter 1)

-          The radio signal from source to reception – a brief recapitulation

-          “Discovery Space”

o   The pros and cons of single dishes, phased arrays and correlation arrays (end of Chapter 11)

o   The Square Kilometre Array (end of Chapter 11)

o   HI in External Galaxies (end of Chapter 14)

o   The Time Variable Radio Sky (end of Chapter 15)

·     Provide URL web addresses where other up-to-date material can be found

The material is arranged by Chapter and can be accessed by clicking the Chapter headings below.

To advise the authors of errata in the main text and/or the Supplementary Material and for

any other comments please use the email address:   




·       Chapter 8: Fig 8.22 the axis label should read “Main beam”


·       Chapter 10:  Equation 10.1 should read:


·       Chapter 16:  Figure 16.2  is incorrectly attributed to  (Peel et al. 2011) whereas it is from Condon (1992) - see references in main text.  The more recent spectrum in Peel et al. is given in Chapter 16 of this Supplementary Material.



(updated 5 December 2019)



Chapter 1: The Role of Radio Observations in Astronomy

New section: Prologue:

·       The radio signal from source to reception – a brief recapitulation

·      Discovery Space”


·       Radio observation bands – a complement to Figure 1.1

·       Early radioastronomy   historic telescopes

·       Additional references for the history of radio astronomy


Chapter 2: Emission and General Properties of Radio Waves

·       Radiation from sources with continuum spectra

o   Thermal black body – the Moon

o   Free-free (Bremsstrahlung) – a planetary nebula

o   Synchrotron – the Crab nebula

o   Anomalous Microwave Emission (AME) – Perseus nebula (not in main text)

o   Coherent emission (not in main text)


Chapter 3: Spectral Lines

·       Atomic Hydrogen

o   Pointers to the quantum physics of the transition

o  Observations of the Milky Way with simple apparatus

o  Further references to HI in the Milky Way

o   The HI4PI all-sky survey

·       Radio Recombination Lines (RRL)

o   State-of-the art RRL observations and the 3-Helium abundance

·       Molecules

o   Spectral scans of the Orion Nebula

·       Masers

·     The Zeeman Effect (not in main text)


Chapter 4: Radio Wave Propagation

·     Faraday Rotation

o  Rotation measure ambiguities

o  Additional effects

o  Depolarisation

o  Faraday Depth and Rotation Measure Synthesis

·     Scintillation

o   Dynamic frequency spectra observed from a pulsar


Chapter 5: The Nature of the Received Radio Signal


·       Early microwave measurements of the surface temperatures of planets

o   Illustration of beam dilution and flux density approaches



Chapter 6: Radiometers


·       Schematic illustration of the action of a mixer

·       Receiver temperature calibration

·       The universality of “1/f noise”

·       Schematic signal flow in a DIcke-switch system

·       State-of-the-art Dicke-switch applications

·       An example twin-beam radiometer – the 30 GHz OCRA-p system

·       Schematic of a basic correlation receiver

·       A simplified schematic of a Planck LFI receiver


Chapter 7: Spectrometers and Polarimeters

·     Autocorrelation spectrometers revisited

·        Septum plate polarization splitters


Chapter 8: Single-aperture Radio Telescopes

·       A corrugated horn feed

·       Phased array telescope feeds (PAFs) : ASKAP and APERTIF

·       Measured antenna power patterns

o   Low-cost “cantenna” feed

o   Commercial Yagi

o    Experimental corrugated horn

·       Feed illumination, surface profiles and power beam of a parabolic dish via holography

·       Voltage and power beams  a brief pictorial recapitulation

·     Beam smoothing and angular frequency cut-off

·       Pictures of state-of-the art radio telescopes

o   Fixed reflectors

o   Dishes with adjustable surfaces

o   Dishes at millimeter wavelengths

·       Mapping large areas of sky

o   The classic Haslam 408 MHz all-sky map – with corrections

o   References to other large area maps

·       Twin-beam radiometry – OCRA-p on the Torun 32-m dish

·       Phased array beam patterns - pictorial descriptions

·        Animations of phased arrays

·        Calibration of single dish observations


Chapter 9: The Basics of Interferometry

·       An E-W adding interferometer observing the Sun: a practical example

·       Adding interferometers: constructing visibility amplitudes for point and gaussian double sources

·       The value of model fitting to visibility data

o   An early example -I: the radio jet in the giant elliptical galaxy M87

o   An early example -II: the radio jet in the quasar 3C147

·       Plots of visibility amplitudes for some simple sources


Chapter 10: Aperture Synthesis

·       The JVLA Observers Reference Manual: a mine of useful information

·       Interferometric imaging – developing methods

o   WSRT image showing coherent “ring lobes”

o   Imaging the “Black Hole Shadow” in M87:

·       The power of modern synthesis imaging

o   Snapshots plus MFS producing an image of M82

o   Production of multi-array VLA image of Hercules A

·       Basic Interferometric imaging: resources

·       Continuum calibration and image error analysis: resources

·         Pictures of interferometer arrays: metre-centimetre wavelengths


Chapter 11: Further Interferometric Techniques

·       Interferometer Arrays

o   At mm-wavelengths

o   At long wavelengths

o   Very Long Baseline Networks

o   Space VLBI

o   Special Purpose Arrays

·       Techniques in Aperture Synthesis: resources

o   Spectral Lines

o   Polarisation

o   Millimetre wave interferometry

o   Wide-field imaging example

o   Mosaicing

o   Filling in short spacings with single dish data

o   VLBI

o   Wide-field Imaging

o   Astrometry:

§  update on ICRF3 and link with Gaia

§  new astrometric applications in the Solar System

o   Geodesy

§   An introduction/overview

§   The increasing separation of a transatlantic baseline

§   Update on the world-wide geodetic array VLBI2010


o   The SMOS Earth resources satellite


New Section: The pros and cons of single dishes vs. phased arrays vs. aperture synthesis arrays

·       Comparisons

·       Routes to survey speed improvements


New Section: The Square Kilometre Array

·       Public website

·       Science website


Chapter 12: The Sun and the Planets

·        Further overview of the radio sun

·       Observations at meter wavelengths

·       Observations at centimeter wavelengths

o   The Nobeyama radioheliograph and its daily image of the Sun

·       Observations at millimeter wavelengths – from ALMA

o   The solar disk

o   Sunspots

·     The Planets


Chapter 13: Stars and Nebulae

·       Stars

o   Red Giants

o   Asymptotic Giant Branch (AGB)

o   The diagnostic role of masers in the life history of stars

o   Silicon Monoxide maser shells around evolved stars

o   Circumstellar disks

o   Evolved stars: a planetary nebula

o   Young stellar objects (YSOs)

o   Massive star-forming regions: methanol masers as pointers

·       Microquasars/XRBs

·       Nebulae

o   HII regions

o   Molecular Clouds

o   Supernova Remnants


Chapter 14: The Milky Way Galaxy

·       Continuum emission            

o  Multiwavelength surveys and the Chromoscope visualisation tool

o   Large area maps of the diffuse continuum emission

o   Spectra of the components of the diffuse emission

o   Higher resolution imaging

·       Galactic Magnetic Field

o   Rotation Measures in the Milky Way

o   Magnetic fields in an external spiral galaxy

·       Spectral Lines

o   The Milky Way in HI

o   The Galactic Plane in CO

·       Future radio studies and the ISM


New Section: HI in external galaxies

·       Early WSRT measurements of rotation in M81

·       The THINGS survey and its results

·       The Local Volume HI Survey (LVHIS)

·       The WALLABY and APERTIF surveys

·       The SKA and HI

·       Tidal effects in the M81 group of galaxies


Chapter 15: Pulsars

·       The discovery of pulsars

·       The sounds of pulsars

·       Positions of pulsars and MSPs in galactic coordinates

·       The P/Pdot diagram

·       Pulsar Spectra

·       The Crab Nebula

·       Pulsar Wind Nebulae

·       Bow shocks

·       Pulse de-dispersion - the incoherent approach

·       Coherent de-dispersion


New section: The Time Variable Radio Sky

·       Overviews

·       Fast Radio Bursts  


Chapter 16: Active Galaxies

·       Starburst galaxies

o   M82 and its supernovae

o   Arp 220 and its  supernovae

·       Active Galactic Nuclei (AGN)

o  Review papers on central engines and relativistic jets

o  Extended double radio sources

o  Imaging the AGN torus in Cygnus A

o   Polarisation structure of an extended jet

o   The inner jet in M87

o   The supermassive black hole in the nucleus of M87

o   Interaction of radio lobes with hot intra-cluster gas

·       Faint radio sources

o   Radio quiet AGN

o   Results on the GOODS-North field

o   Source counts at faint flux levels

o   Surveys for faint radio sources

·       Sky simulations for the SKA era (T-RECS)


Chapter 17: The Radio Contributions to Cosmology

·       The Cosmic Microwave Background

o   Overview material

·       The Planck mission

§  ESA animations

§  References to latest products

o   Galactic foreground spectra

o   Polarisation

·       The Sunyaev-Zel’Dovich Effect

o   ESA animation showing frequency dependence

o   Current measurements        

o   Commentary article on the astrophysical importance of galaxy clusters

·       Strong Gravitational Lenses

o   eMERLIN/HST image  of the first gravitational lens to be discovered

o   A VLBI image of an extended lensed arc

o   An ALMA lens image

o   The JVAS/CLASS lens survey

o   Lens time delays and Ho



1: Fourier Transforms

·       Autocorrelation: pictorially

·       The wide applicability of the Convolution Theorem

·       Convolution and linear systems – the Fourier approach

2:  Celestial Coordinates and Time

·       Further references

3: Digitization

·       Further reference

4: Calibrating Polarimeters

·       Further references

5: Spherical Harmonics

·       Reference for the HEALPix primer