Physical Principles of Astronomical Instrumentation

Cover
Half Title
Series Page
Title Page
Copyright Page
Table of Contents
Preface
Authors
Chapter 1 Review of Electromagnetic Radiation
	1.1 Introduction
	1.2 Mathematical Description of Waves
	1.3 Maxwell’s Equations
	1.4 Electromagnetic Waves
	1.5 Plane EM Waves
	1.6 Energy in EM Waves
	1.7 Wave Particle Duality
	1.8 Interaction of EM Radiation with Charged Particles
	1.9 Complex Number Representation of Waves
	1.10 Superposition and Wave Interference
	1.11 Radiative Transfer
		1.11.1 Flux, Flux Density, and Intensity
		1.11.2 The Equation of Radiative Transfer
		1.11.3 Emission Only
		1.11.4 Absorption Only
		1.11.5 Thermal Equilibrium
		1.11.6 Thermal Emission from a Semi-Transparent Region
		1.11.7 Transmission of the Earth’s Atmosphere
	1.12 Polarisation
		1.12.1 Linear, Circular, and Elliptical Polarisation
		1.12.2 Stokes Parameters
Chapter 2 Astrophysical Radiation
	2.1 Astrophysical Radiation Mechanisms
	2.2 Black Body Radiation and the Planck Function
		2.2.1 Rayleigh–Jeans and Wien Regions
		2.2.2 Wien’s Displacement Law
		2.2.3 Stefan’s Law
		2.2.4 Emissivity
	2.3 Free–Free Radiation
	2.4 Non-Thermal Emission Mechanisms: Cyclotron and Synchrotron Radiation
	2.5 Quantum Transitions
		2.5.1 Atomic Transitions
		2.5.2 Molecular Vibrational Transitions
		2.5.3 Molecular Rotational Transitions
		2.5.4 Vibrational-Rotational Transitions
		2.5.5 Line Broadening
			2.5.5.1 Collisional (Pressure) Broadening
			2.5.5.2 Thermal (Doppler) Broadening
		2.5.6 Spectral Line Databases
		2.5.7 γ-Ray Line Emission
	2.6 Polarised Radiation in Astronomy
Chapter 3 Interaction of Electromagnetic Radiation with Matter
	3.1 Radio Wavelengths (λ >~ 1mm)
		3.1.1 The Earth’s Ionosphere
		3.1.2 Antennas
		3.1.3 Detection of the Intercepted Radiation
	3.2 Infrared-Optical-UV Wavelengths (λ = 1 mm–30 nm)
		3.2.1 Photon Absorption Mechanisms
		3.2.2 Electron Promotion in Semiconductors
		3.2.3 The Photoelectric Effect
	3.3 X-Ray and γ-Ray Wavelengths
		3.3.1 Photoelectric Interaction
		3.3.2 The Compton Effect
		3.3.3 Electron-Positron Pair Production
		3.3.4 Mass Attenuation Coefficient
	3.4 The Effects of the Earth’s Atmosphere
		3.4.1 Atmospheric Absorption
		3.4.2 Atmospheric Emission
		3.4.3 Atmospheric Turbulence and Seeing
		3.4.4 Earth-Based and Space-Borne Observatories
Chapter 4 Telescopes and Optical Systems
	4.1 Introduction
	4.2 Telescope Configurations
	4.3 Telescope Mounting Methods
	4.4 Telescope Optics
		4.4.1 Lens Optics
		4.4.2 Mirror Optics
		4.4.3 The Plate Scale
		4.4.4 Telescope Throughput
	4.5 Optical Aberrations
		4.5.1 Spherical Aberration
		4.5.2 Coma
		4.5.3 Astigmatism
		4.5.4 Field Curvature
		4.5.5 Distortion
		4.5.6 Chromatic Aberration
	4.6 Diffraction
		4.6.1 The Rayleigh Criterion
		4.6.2 Beam Profile or Point Spread Function
		4.6.3 Strehl Ratio
	4.7 Fourier Optics
	4.8 Spatial Interferometry
Chapter 5 Key Concepts in Astronomical Measurement
	5.1 Introduction
	5.2 Transduction
	5.3 The Decibel Scale
	5.4 Responsivity
	5.5 Response Time (Speed of Response)
	5.6 Background Radiation
	5.7 Noise and Signal-to-Noise Ratio
	5.8 Electrical Filtering and Integration
	5.9 Nyquist Sampling
	5.10 Linearity
	5.11 Dynamic Range
	5.12 Types of Measurement: Photometry, Spectroscopy, Spectro-photometry
	5.13 Calibration
		5.13.1 The Stellar Magnitude System
		5.13.2 Standard Filter Bands
		5.13.3 Colour Correction
Chapter 6 Sensitivity and Noise in Electromagnetic Detection
	6.1 Introduction
	6.2 An Ideal Photon Detector
	6.3 Noise Equivalent Power
		6.3.1 Background-Limited NEP
	6.4 Efficiency of Photon Detectors
		6.4.1 DQE and NEP of an Imperfectly Absorbing but Noiseless Detector
	6.5 Photon Shot Noise and Wave Noise
	6.6 Background Photon Noise-Limited NEP of a Broadband Detector
		6.6.1 NEPph for a Photon-Counting Detector
		6.6.2 NEPph for Broadband Power Detector
	6.7 Additional Sources of Noise
		6.7.1 Thermal Noise from a Resistor
		6.7.2 Electron Shot Noise
		6.7.3 Generation-Recombination Noise
		6.7.4 Phonon Noise
		6.7.5 1/f - Noise
		6.7.6 kTC Noise
		6.7.7 Interference
		6.7.8 Microphonic Noise
	6.8 Combination of Noise from Several Sources
		6.8.1 Overall Noise and NEP
	6.9 Optimising a System for Best Sensitivity
		6.9.1 Choosing the Signal Frequency or Frequency Band
		6.9.2 Choosing the Post-Detection Bandwidth
		6.9.3 Minimising Noise from the Detector and Its Readout and Signal-Processing Electronics
	6.10 Noise Equivalent Flux Density
Chapter 7 Astronomical Spectroscopy
	7.1 Introduction
	7.2 Spectrometer Types
	7.3 Prism Spectrometers
	7.4 Grating Spectrometers
		7.4.1 The Grating Equation and Grating Dispersion
		7.4.2 Grating Response to a Monochromatic Source
		7.4.3 Spectral Resolving Power
		7.4.4 Free Spectral Range and Order-Sorting
		7.4.5 Effect of Finite Slit Width
		7.4.6 Blazed Gratings and Grating Efficiency
		7.4.7 Optical Matching between an Astronomical Source and a Grating Spectrometer
		7.4.8 The Echelle Spectrograph
		7.4.9 Grisms
	7.5 Fabry-Perot (FP) Spectrometers
		7.5.1 The Fabry-Perot Interferometer
		7.5.2 Free Spectral Range and Resolving Power
		7.5.3 Fabry-Perot Spectrometers
		7.5.4 Effects of Plate Absorption and Other Imperfections
		7.5.5 Rejection of Unwanted Orders
	7.6 Fourier Transform Spectrometers
		7.6.1 The Michelson Interferometer as a Fourier Transform Spectrometer
		7.6.2 Spectral Sampling
		7.6.3 Spectral Resolution and the Instrument Response Function
		7.6.4 Effect of a Non-Parallel Beam on Spectral Resolving Power
		7.6.5 FTS Operation and Data Reduction
	7.7 Advantages and Disadvantages of Different Spectrometer Types
	7.8 Grating Spectrometer Instruments
		7.8.1 Integral Field Units (IFU) and Multi-Object Spectrometers (MOS)
Chapter 8 Radio Instrumentation
	8.1 Introduction
	8.2 Antennas
		8.2.1 Antenna Beam Pattern
		8.2.2 Gaussian Telescope Illumination
		8.2.3 Antenna Efficiencies
	8.3 Radio Receivers
		8.3.1 Power Received by a Radio Antenna
		8.3.2 The Total Power Radiometer
		8.3.3 System Temperature
		8.3.4 The Superheterodyne Receiver
		8.3.5 The Superheterodyne Total Power Receiver
		8.3.6 Quantum-Limited System Temperature
		8.3.7 Minimum Detectable Temperature and Power
	8.4 Mixers and Amplifiers
		8.4.1 The Schottky Diode Mixer
		8.4.2 Superconductor-Insulator-Superconductor (SIS) Mixers
		8.4.3 Hot Electron Bolometer Mixers
		8.4.4 High Electron Mobility Transistors
	8.5 Local Oscillators
	8.6 IF Spectrometers
		8.6.1 The Multichannel (Filter Bank) Spectrometer
		8.6.2 The Acousto-Optic Spectrometer (AOS)
		8.6.3 The Digital Autocorrelation Spectrometer
		8.6.4 The Direct FFT Spectrometer
	8.7 Radio Observations
		8.7.1 Source Antenna Temperature
		8.7.2 Sensitivity to a Point Source
		8.7.3 Calibration Methods
	8.8 Radio Interferometry
		8.8.1 The Two-Element Radio Interferometer
		8.8.2 The Effect of Finite Bandwidth
		8.8.3 Fringe-Stopping
		8.8.4 Beam Synthesis
		8.8.5 Interferometer Observation of an Extended Source
		8.8.6 The uv Plane and Aperture Synthesis
		8.8.7 Interferometer Sensitivity
	8.9 Case Studies
		8.9.1 The 4-mm Receiver on the Green Bank Telescope
		8.9.2 The GREAT Spectrometer on Board the SOFIA Airborne Observatory
		8.9.3 The MeerKAT Radio Interferometer
Chapter 9 Far-Infrared to Millimetre Wavelength Instrumentation
	9.1 Introduction
	9.2 Direct Detection Instruments
	9.3 Bolometric Detectors
		9.3.1 Bolometer Responsivity
		9.3.2 Bolometer Time Constant
		9.3.3 Bolometer Noise and NEP
		9.3.4 Dependence of Achievable Bolometer NEP on Operating Temperature
		9.3.5 Semiconductor Bolometers
		9.3.6 Semiconductor Bolometer Readout Electronics
		9.3.7 TES Bolometers
		9.3.8 TES Bolometer Readout Electronics
	9.4 Kinetic Inductance Detectors
	9.5 Choice of Bolometric and KID Detectors for the Far Infrared and Submillimetre
	9.6 Photoconductive Detectors
		9.6.1 Responsivity
		9.6.2 Dark Current
		9.6.3 Noise
		9.6.4 NEP
		9.6.5 Photoconductor Readout Electronics
	9.7 Choice of Photoconductors for the Far Infrared
	9.8 Coupling FIR and Submillimetre Detector Arrays to the Telescope
		9.8.1 Antenna-Coupled Arrays
		9.8.2 Absorber-Coupled Arrays
	9.9 Case Studies
		9.9.1 Herschel-SPIRE: A Space-Borne FIR-Submillimetre Camera and Spectrometer
		9.9.2 Spitzer-MIPS: A Space-Borne FIR Camera
		9.9.3 SCUBA-2: A Ground-Based Submillimetre Camera
Chapter 10 Infrared to UV Instrumentation
	10.1 Introduction
	10.2 Infrared Detectors
		10.2.1 Photodiodes
		10.2.2 Infrared Photodiode Materials
		10.2.3 Infrared Photodiode Arrays
		10.2.4 Blocked Impurity Band (BIB) Photoconductive Detectors
	10.3 Optical and UV Detectors
		10.3.1 Charge-Coupled Devices (CCDs)
			10.3.1.1 Charge Transfer and Readout
			10.3.1.2 Buried Channel CCDs
			10.3.1.3 CCD Quantum Efficiency and Spectral Response
			10.3.1.4 CCD Noise
			10.3.1.5 Charge Multiplying CCDs
			10.3.1.6 CCD Performance Parameters
			10.3.1.7 Main Advantages of CCDs
			10.3.1.8 CCD Operation
		10.3.2 The Photomultiplier Tube
		10.3.3 The Microchannel Plate
		10.3.4 The Avalanche Photodiode
	10.4 Adaptive Optics
		10.4.1 Adaptive Optics Systems
	10.5 Case Studies
		10.5.1 The WFPC 3 Instrument on the Hubble Space Telescope
		10.5.2 The K-Band Multi-Object Spectrometer (KMOS) on the ESO-VLT
		10.5.3 MICADO – An Imager for the Extremely Large Telescope
Chapter 11 X-Ray, γ-Ray, and Astro-Particle Detection
	11.1 Introduction
	11.2 X-ray CCDs and Fano Noise
	11.3 The Proportional Counter
	11.4 X-Ray Spectroscopy
	11.5 The X-Ray Calorimeter
	11.6 Scintillation Detectors
	11.7 Semiconductor Detectors: Silicon, Germanium, and Mercury Cadmium Telluride
	11.8 X- and γ-Ray Imaging
		11.8.1 Grazing Incidence X-Ray Telescopes
		11.8.2 Coded Mask Imaging
		11.8.3 The Compton Telescope
		11.8.4 Pair Creation Detectors
	11.9 High-Energy γ-Ray and Cosmic Ray Detection
		11.9.1 Extensive Air Showers
		11.9.2 Čerenkov Radiation
		11.9.3 Extensive Air Shower Observatories
	11.10 Cosmic Neutrino Detection
	11.11 Case Studies
		11.11.1 XMM-Newton and Its Instruments
		11.11.2 The Swift Satellite and Its Instruments
		11.11.3 The Fermi Large Area Telescope
		11.11.4 The VERITAS Čerenkov Telescope Array for High-Energy Gamma-Ray Astronomy
		11.11.5 The IceCube Neutrino Observatory
Bibliography
Index