Name: Essential Radio Astronomy
ISBN: 9780691137797

Essential Radio Astronomy

"Essential Radio Astronomy is the only textbook on the subject specifically designed for a one-semester introductory course for advanced undergraduates or graduate students in astronomy and astrophysics. It starts from first principles in order to fill gaps in students' backgrounds, make teaching easier for professors who are not expert radio astronomers, and provide a useful reference to the essential equations used by practitioners. This unique textbook reflects the fact that students of multiwavelength astronomy typically can afford to spend only one semester studying the observational techniques particular to each wavelength band. Essential Radio Astronomy presents only the most crucial concepts—succinctly and accessibly. It covers the general principles behind radio telescopes, receivers, and digital backends without getting bogged down in engineering details. Emphasizing the physical processes in radio sources, the book's approach is shaped by the view that radio astrophysics owes more to thermodynamics than electromagnetism. Proven in the classroom and generously illustrated throughout, Essential Radio Astronomy is an invaluable resource for students and researchers alike."--Publisher's description.

What Hacker News says

ajfordNov 2022

Intro to Radio Astro Interferometry by Thompson and Intro to Radio Astro by Burke and Graham-Smith are strong recommendations. Those were the ones I used in my Radio Astro special topic in Uni.

For some more background info, Essential Radio Astronomy open notes hosted by the National Radio Astronomy Observatory [0] are a great resource as well. This was used as an extra resource in my Radio Astro course. The ERA notes were also later extended into a textbook [1], which I haven't used but have heard it's well done.

[0]: https://science.nrao.edu/opportunities/courses/era/ [1]: https://press.princeton.edu/books/hardcover/9780691137797/es...

thread

raattgiftJul 2023

The millisecond pulsars in the international pulsar timing arrays https://ipta4gw.org/ are all within the Milky way. There is no metric expansion of space within the Milky way. The pulsars (and our solar system) are all on ~Keplerian orbits through the galaxy, and relative motion between us and them is small.

> If the distance is great enough

It's not, in this context.

> Stars don't stay put

Close enough, in this context. The uncertainties ("red noise") in PTA timing residuals from scattering in the interstellar medium and local properties (mostly internal structure) of the pulsars dwarf the uncertainties in relative motion.

PTAs also care about the pulse timing not the carrier of the pulse. That is, the beam points at us with a predictable period and that period evolves (in parts per million) in the presence of nanohertz gravitational waves. The beam itself is broadband (radio to gamma rays) and any spectral line structure could be anything (most likely the interstellar medium).

Detailed redshift studies look at the spread of spectral lines, particulary the Lyman and Balmer series, and pulsars are what you get when there's no hydrogen left to fuse. ("Finally, pulsars have broadband continuum spectra, so if there are gas clouds along our line of sight, pulsars can be used to probe the ISM via absorption by spectral lines of Hi or molecules. Such absorption spectra can be used to estimate pulsar distances" -- end of §6.2 of Condon & Ransom's Essential Radio Astronomy advanced undergraduate one-semester-course textbook (2016 ed.), web version at https://www.cv.nrao.edu/~sransom/web/Ch6.html )

I have a related comment in this thread if you're interested.

thread