Particle physics research
The Large Hadron Collider (or LHC) is large, with a circumference of 27 km. A hadron is any particle made up of quarks (protons and neutrons belong to this family). In the LHC, counter-rotating beams of protons are accelerated to very high speeds and then made to collide at four points where the two rings of the machine intersect.
What is the CMS?
In this video. Dr David Krofcheck explains his involvement at the LHC with a general-purpose detector known as the CMS. Buried deep within the huge Compact Muon Solenoid structure are radiation sensors designed and built by David’s team. The project is a collaboration involving many physicists from around the world.
Point of interest
When you look at photos of the CMS, give some thought to the engineers, scientists and technicians who designed, constructed, installed, tested and operate this huge machine.
CERN stands for Conseil Européen pour la Recherche Nucléaire (or European Council for Nuclear Research). It was founded 54 years ago, and over 20 European countries now belong. A further eight observer countries and a number of non-member countries (including New Zealand) assist with research. The main research facility, situated in Geneva on the Franco-Swiss border, is the world’s largest particle physics laboratory.
Dr David Krofcheck is involved with the CMS, which stands for Compact Muon Solenoid. CMS is a general purpose detector designed to capture the flood of subatomic particles produced when the protons collide. Muons belong to the lepton particle family. They are a heavier ‘relative’ of the electron with only a fleeting existence. Auckland University’s role is to help develop and perform tests of the Beam Radiation Monitoring detectors and to work on data analysis of proton–proton and lead ion–lead ion reactions.
CERN accelerator complex
Accelerator complex at CERN
Arrows:
Abbreviations:
Grey = p (proton)
LH
Large Hadron Collider
Orange = neutrons
SPS
Super Proton Synchrotron
Green = p (antiproton) [with line above letter p]
PS
Proton Synchrotron
Grey | green = proton/antiproton conversion
AD
Antiproton Decelerator
Light blue = neutrinos
CTF3
Clic Test Facility
Brown = electron
CNGS
Cern Neutrinos to Gran Sasso
ISOLDE
Isotope Separator OnLine DEvice
LEIR
Low Energy Ion Ring
LINAC
LINear ACcelerator
n-ToF
Neutrons Time Of Flight
The accelerator complex at CERN is a succession of machines that can accelerate positively charged protons and lead ions to extremely high energies before allowing them to collide head on.
The accelerator complex at CERN is a succession of machines designed to accelerate charged particles like protons to very high speeds. The last machine in the chain – the Large Hadron Collider (LHC) – is designed to allow counter-rotating beams of charged particles to be accelerated to extremely high speeds before allowing them to collide.
What is the cost?
To construct a tunnel 27 km in diameter at an average depth of 100 m is a huge undertaking. Many civil engineering problems had to be solved. The construction costs alone run into billions of dollars.
To run the experiments, complex machines and detectors are needed. These are costly to design and build. When operating, they require a huge amount of electrical energy, and this too costs money. Highly qualified scientists and technicians are employed to operate the facility, once again adding to the cost.
What is a particle accelerator?
Dr David Krofcheck explains what a particle accelerator is and how it works. He then goes on to explain how the world’s largest particle accelerator – known as the Large Hadron Collider – operates. The collider is 27km in circumference and can accelerate protons to extremely high kinetic energies. This allows physics to be explored in new regions of energy.
Point of interest
What is a superconducting magnet
The direct total LHC project cost is about $10 billion, shared mainly by CERN’s 20 Member States, with significant contributions from the eight observer nations.
The LHC project involves 111 nations in designing, building and testing equipment and software, participating in experiments and analysing data. The degree of involvement varies between countries, with some able to contribute more financial and human resource than others.
What are the benefits?
Dr David Krofcheck has strong views on this issue:
Engineering research and development has benefited enormously from the physics requirements to study fundamental forces of nature – marvellous feats of engineering, large scale and small scale.
There are two main benefits of investing such a huge amount of money into this project.
New understandings
The LHC allows us to test theories and ideas about how the universe works, its origins and evolution. The questions asked, and answers found, are so fundamental that the information from experiments being conducted at CERN could lead in the future to great benefits for mankind.
Find out more about how CERN creates mini big bangs.
Spin-offs
The knowledge, expertise and technology that has been developed from the LHC can be directly applied to development of new medical, industrial and consumer technologies, which can find their way into everyday use.
The most famous technology is the World Wide Web, which was developed by Sir Tim Berners Lee while he was working at CERN. Another more recent development is the Medipix chip, which was developed for use in particle detectors. It is highly sensitive and has found applications in other imaging and detection systems, for example, in medical imaging where greater sensitivity means lower doses and reduced exposure times of radiation can be used.
Perhaps the most valuable benefit is the community of practice that has evolved from this project. It is funded by and built in collaboration with over 10,000 scientists and engineers from over 100 countries, as well as hundreds of universities and laboratories.
Nature of Science
Nowadays, scientists tend to work as part of a team and there is a community of practice operating within the given field.
Useful link
Check out this 360 degree video from the BBC that gives an interactive tour of Cern's Large Hadron Collider.
