This textbook provides an accessible yet comprehensive introduction to detectors in particle physics. It emphasises the core physics principles, enabling a deeper understanding of the subject for ...further and more advanced studies. In addition to the discussion of the underlying detector physics, another aspiration of this book is to introduce the reader to practically important aspects of particle detectors, like electronics, alignment, calibration, and simulation of particle detectors. Case studies of the various applications of detectors in particle physics are provided.
The primary audience is graduate students in particle or nuclear physics, in addition to advanced undergraduate students in physics.
Key Features:
Provides an accessible yet thorough discussion of the basic physics principles needed to understand how particle detectors work.
Presents applications of the basic physics concepts to examples of modern detectors.
Discusses practically important aspects like electronics, alignment, calibration and simulation of particle detectors.
Contains exercises for each chapter to further understanding.
Both authors have a long experience in teaching undergraduate and graduate students at the University of Oxford.
This book gives a modern introduction to particle physics. The main mathematical tools required for the rest of the book are developed in Chapter 2. A quantitative introduction to accelerator physics ...is presented in Chapter 3. Chapter 4 covers detector physics, with an emphasis on fundamental physical principles. Chapter 5 covers the static quark model, with applications to light mesons and baryons as well as heavier states containing charm and beauty quarks. Chapter 6 introduces relativistic quantum mechanics and uses spinors to relate Lorentz invariance to the Dirac equation. Chapter 7 covers the basics of the electroweak theory based on broken SU(2) × U(1) symmetry. Chapter 8 reviews some of the key experiments that led to the development of the electroweak theory. Chapter 9 explains the importance of deep inelastic scattering data for providing direct evidence for the existence of quarks. It also gives a brief introduction to quantum chromodynamics (QCD). Chapter 10 considers flavour oscillations in the quark sector and then discusses the evidence for CP violation. Chapter 11 examines the theory of neutrino oscillations as well as the evidence for these oscillations. Chapter 12 gives an elementary introduction to the Higgs mechanism as well as a careful explanation of the experimental evidence for the existence of a Higgs boson. Chapter 13 looks at LHC physics and explains how searches for Beyond the Standard Model Physics are performed. It concludes with a discussion of the evidence for dark matter and dark energy.
In chapter 2 we have seen that the interaction of an incoming charged particle with the detector material results in a number of energy transfers along the track that can lead to the ionisation of ...the detector material, creating pairs of negative (usually electrons) and positive (positive ions or holes) charge carriers. In chapter 3 we have seen how the movement of charges creates a current signal on a system of readout electrodes of an electronic particle detector. To create this signal, we have first, to separate the charges, and then, second, to keep them moving, as the induced current depends on their drift velocity in the external fields. To collect these charges for electrical readout, they need to be mobile, with a low probability for capture and recombination. Viable detector materials are therefore non-polar pure gases or liquids, or pure or lightly doped semiconductors.
Triggers Viehhauser, Georg; Weidberg, Tony
Detectors in Particle Physics,
2024, Volume:
1
Book Chapter
Open access
In general, in particle physics interesting events and the response they produce in detectors are instantaneous, or they have a very short duration given by decay lifetimes. This duration can be ...increased by the finite response time of the detectors, but is still very short compared to the operational time of the experiment. Other events, from interesting physics or backgrounds, will take place before and after, and thus, in general, the experiment will need to identify the occurrence of specific events in time and record the information from its detectors for this instance. This identification is provided by the trigger.
Tracking Viehhauser, Georg; Weidberg, Tony
Detectors in Particle Physics,
2024, Volume:
1
Book Chapter
Open access
Tracking detectors are designed to reconstruct the trajectories of charged particles as they traverse the tracking volume. Usually a magnetic field will be present in this volume. In this field, the ...trajectories will curve and we can reconstruct the momentum of the charged particles from the curvature of the track. From the direction of the curvature we can determine the sign of the charge of the particle.
Gaseous detectors Viehhauser, Georg; Weidberg, Tony
Detectors in Particle Physics,
2024, Volume:
1
Book Chapter
Open access
When a charged particle passes through a gas, it will create ionisation charges as described in section 2.3. If an electrical field is applied, the charges will separate and drift towards the ...electrodes (see section 4.1), which induces electrical signals on the electrodes as discussed in section 3.1.
The biggest challenge for the detection of subatomic particles is clearly the small amount of energy these particles carry. A TeV particle has about
10
−
7
J of energy and the momentum is about
10
−
...15
kgm/s, so that direct mechanical observation is not possible.
Electronic signals and noise Viehhauser, Georg; Weidberg, Tony
Detectors in Particle Physics,
2024, Volume:
1
Book Chapter
Open access
In chapter 2 we considered the different ways in which high energy particles deposit their energy in matter. Now we will consider how to use the results of these interactions to create a measurable ...signal in a detector.
Calorimetry Viehhauser, Georg; Weidberg, Tony
Detectors in Particle Physics,
2024, Volume:
1
Book Chapter
Open access
In the previous chapters we have seen how the quasi-continuous small energy loss of charged particles enables the detection of these particles in tracking detectors, typically made of thin detector ...layers. A different approach is taken in calorimeters, where the particle ultimately is fully absorbed. If the particle has a high energy it is lost in a cascade of secondary interactions until all particles in the cascade have come to a stop. Despite the name, calorimeters in particle physics usually do not measure the heat generated in the detector material, as this is usually too small to be detected, except at extremely low temperatures, and the typical signal is either ionisation charge or scintillation light.
