**“ Radio
Astronomy: Tools, Applications &
Impacts”**

Who: U. Klein

When: Winter term, Tuesday 4:15 p.m., Thursday 4:15 p.m.

Where: AIfA, HS 0.03

This lecture is supposed to be attended by students studying main
courses.
Successful participation in the
course on
Theoretical Electrodynamics is a prerequisite; in addition, elementary
courses in
physics and
mathematics are required. A successful participation in this class
means **3 academic hours**
of lecturing per week, **plus**
participation in the associated **lab
course**. The latter usually takes place
after the winter term (in a block).

Note that students in the Master of Astrophysics programme may perform this lab course as part of the advanced lab.

Any students who envisage a
thesis in radio
astronomy are **strongly
recommended** to
attend this lecture! In what follows a syllabus of the lecture is
given, which is still subject to changes since it had to be 'glued
together'
from previously two courses.

**1.
Introduction**

history

astrophysics and radio
astronomy

**2.
Single-dish telescopes**

Cassegrain and Gregory foci

geometries and ray tracing

antenna diagrams

antenna parameters

**3.
Fourier optics**

Fourier transform

aperture – farfield relations

spatial frequencies and filtering

power pattern

convolution and sampling

resolving power

**4.
Influence of earth’s
atmosphere**

ionosphere, troposphere

plasma frequency

Faraday rotation

refraction, scintillation

absorption / emission

radiation transport

**5****.
Receivers**

total-power and heterodyne systems

system temperature

antenna temperature, sensitivity

Dicke-, correlation receiver

amplifiers

hot-cold calibration

**6. Wave
propagation in
conductors
coaxial cables, waveguides
matching, losses
quasi optics
7. Backend
continuum, IF-polarimeter
spectroscopy
filter spectrometer
autocorrelator
acousto-optical spectrometer
pulsar backend
8. mm and submm
techniques**

telescope parameters and observables

atmosphere, calibration, chopper wheel

error beam

SIS receivers

bolometers

on-off, cross-Scan, Raster

continuous mapping, OTF, fast scanning

frequency-switching, wobbling technique

10. Data analysis

sampling theorem

spectroscopy

multi-beam observations

image processing, data presentation

aperture - image plane

complex visibility

delay tracking

fringe rotation

sensitivity

12. Imaging

Fourier inversion

cleaning techniques

self-calibration

zero-spacing correction

13. VLBI

station requirements

processor

calibration and imaging

retarded baselines

geodesy

XF and FX correlation

data cubes

15. Polarimetry

cross dipoles

circular feeds

spurious polarization

projects, telescopes

LOFAR, SKA, ALMA, SOFIA, Planck

impacts: ISM, IGM, cosmology ...