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An Insight Into Nature's Strongest Force

Introduction:

My name is Lloyd and I am in the third year of my PhD studying Theoretical Nuclear Physics. I am attempting to provide a better theory to describe the phenomenon of neutral pion (a relatively light, short-lived particle that is found in nuclear and particle reactions) production from a photon (light) incident on a proton (a nuclear particle that is found in the nucleus of every atom).  Before starting my research I studied theoretical physics at the University of Manchester.


Strong Nuclear forces remain to be one of the least understood processes in nature. Yet it is the source of immense energy that can power our cities, from harnessing the emitted radiation in power-plants; or level countries by concentrating radioactive materials in a bomb. The manner in which the fundamental matter particles (or quarks) exchange the strong force carrying particle (or the gluon boson) is far more complex than any of the other forces (weak nuclear, electromagnetic or gravity). Unlike the other forces, gluons themselves can carry a strong nuclear charge, known as colour charge; this allows them to interact with themselves in-between quark interactions, allowing for infinite scenarios to describe the simplest of processes. 

In Depth:

The study of the strong nuclear force is known as quantum chromodynamics (QCD), this theory helped scientists understand important properties of particle physics, mainly why we only see composite quark states in nature. In other words why you will never find a sole quark by itself, instead you will see it in bound states (hadrons) which form protons and neutrons (baryons) and lighter states such as pions (mesons). But trying to make any practical calculations with QCD is very difficult, so difficult in fact that if anyone were to solve the QCD equation into a usable form then they would win 1 million dollars from the Clay Mathematics Institute!

I do away with these complexities of QCD by only working in energy regimes where the protons and other hadrons won't break down into their constituent quarks. So we can describe proton or neutron scattering through pion exchange instead of using gluons. Furthermore, I take advantage of some symmetries present in QCD, related to the quark masses, to simplify aspects of the calculations. This is a very vague picture of the theory I work in called Chiral Perturbation Theory (ChPT).


My work has been motivated by a recent experiment in Germany at the Mainz Microtron by the A2 and CB-TAPS collaborations where they have obtained the most accurate data to date on this interaction. I am in the process of taking theories that have already been made to describe parts of this process and sticking them together to get a more complete picture of the reaction. The most important part I have included is an intermediate resonance state prior to pion emission.

This research isn't going to be part of the new fastest computer in 20 years time, nor is it going to cure diseases. But it will give us an insight in to what happens in nature at the sub-atomic level. Then maybe who knows what this might lead to in the future, 100 years from now it is impossible to predict how important this process will be in understanding nuclear fusion both in power plants or in stars. When Paul Dirac, one of the pioneers of quantum mechanics, predicted the existence of massless Dirac fermions in the 1920s he had no idea that a century later people would be trying to use these states within graphene to dramatically improve technology.

Going Further:

To follow exactly what it is I do I am afraid you will need a degree in theoretical physics, which you can start looking into at the University of Manchester. (http://www.physics.manchester.ac.uk/study/undergraduate/undergraduate-courses/physics-with-theoretical-physics-mphys/)

The European Centre for Nuclear Research (CERN) have lots of information available on particle and nuclear physics (http://home.web.cern.ch/students-educators)

The Jefferson Lab in the USA also has useful information for students and teachers (https://www.jlab.org/education-students)

MAMI, the experimental group that analyse this interaction (http://www.kph.uni-mainz.de/eng/108.php)


 

Science and Engineering have the power to change the world we live in!

Introduction

My name is Marcello and I earned my PhD in particle physics at the University of Manchester, in 2013. Since then, I have been working as a researcher for the Science and Technology Facilities Council (STFC). 

STFC is a UK government body that carries out civil research in science and engineering, and funds UK research in areas including particle physics, nuclear physics, space science and astronomy.

I work in the technology department and I am involved in projects dealing with the building of instrumentation for experiments in nuclear physics. This type of instrumentation is not available commercially because it has very particular requirements. Hence, STFC employs dedicated teams of physicists and engineers to build this type of equipment. And I am one of them!

My experience.

I decided to continue my education after the age of 18 and so enrolled in a bachelor’s degree of physics at the University of Manchester. This decision opened up many opportunities in my life.

I gained an objective view of natural phenomena and increased my employability.

Science and engineering have the power to change the world we live in. These subjects produce the most amazing technology and fuel the economy of many countries. For this reason, the analytical thinking of a physicist is highly valued in the job market.

As a student, I did not always find physics easy to understand and did not like all of its different branches equally. My favorite topic is the interaction of radiation with matter, so I decided to specialize in this area for my masters and PhD.

An education in physics gave me the opportunity to study and work in an environment which is professional, multicultural and at the forefront of human knowledge.

From the neighborhood I grew up in, I found myself involved in international projects investigating important questions about our existence. I spent time in laboratories in other countries to exchange information about my work. During this time, I also made strong friendships and discovered new places.

The knowledge I gained in high-school in mathematics, physics and computer science, has been beneficial to my career.

To summarise, I wanted to include some figures about salaries of researches in the initial and middle stages of their careers:

-  PhD student (22-25 years old): about £12,000 per year. 

-  Post-doc researcher (25-35 years old): from £28,000 to £35,000 per year.

-  Academic staff or senior researcher (35-45 years old): from £35,000 to £45,000.

Salaries will increase even further for managerial positions within Universities or Research Institutes and are generally higher in the private sector.

Further details

Apprenticeships are really good opportunities to boost your experience in science and engineering and I’ve found that it is easier to find apprenticeships in engineering than in science. Engineering or IT apprenticeships are valuable opportunities for aspiring scientists.

https://www.stfc.ac.uk/1485.aspx

Some organizations that help people to enter top Universities.

http://www.socialmobility.org.uk/

Get involved and become a STEM Ambassador.

http://www.stemnet.org.uk/


 

Researching safe ways to dispose of nuclear waste

Introduction

My name is Robert Worth and I am currently part way through a PhD in Nuclear Engineering with the Nuclear Graphite Research Group at the University of Manchester – how did I get here? Almost by accident. It was during my A Level study in Physics that I first came across the phenomenon of radioactivity, which I thought was a bizarre and exciting process that I had not encountered before, and I needed to know more! This eventually led me to my degree in Mechanical (Nuclear) Engineering at the University of Manchester, which was very enlightening and encompassed many aspects of both mechanical and nuclear engineering. It was during my degree that I stumbled across an email containing upcoming PhD research projects – did I know what a PhD involved? Nope, not really. Did I want to do one? I wasn’t sure. I’m glad I applied, however, as it turned out that this is the sort of work I’d wanted to do all along, I just hadn’t realised it. You are no longer just absorbing information from others – I am also now doing the finding out, and helping answer questions that nobody in the world yet has answers to!

I’ve been very lucky with this PhD project, and have been encouraged to attend many prominent events and conferences around the country, talking with and working alongside some of the most inspiring people and minds in the country. I’ve been fortunate enough to travel further afield too, as far as Lithuania, where we stood on the top of a nuclear reactor core of the same basic design as the famed Chernobyl, and even over to the United States, to visit a research group at Idaho State University and to help on an experiment at a synchrotron particle accelerator in California.

My specific research project is on thermal treatment of irradiated graphite waste. It turns out that there is an awful lot of it (around 96,000 tonnes) in our small country, the UK. So far, there are good ideas about how we might deal with this large volume of radioactive waste, and the Nuclear Decommissioning Authority (NDA) have plans to bury most of it in a future geological disposal facility, a large controlled facility far underground that could house and contain all of our radioactive waste for thousands of years to come. Since a location for this facility is yet to be found, and it is yet to be built, you could argue that a disposal route is not set in stone. Which is where treatment comes in – can we do something else with the graphite waste to reduce the hazard, instead of burying it, which could potentially save money and may leave valuable space in the repository open for other more hazardous wastes? This is a point of controversy amongst the nuclear waste research community! 

In Depth

What is graphite and how is it used?

Graphite is a very stable hexagonal formation of carbon atoms, that can be found naturally but is also artificially manufactured to very high purities, at great expense! This involves many different processes to reach the final product including heating to around 3000oC for a number of days. It is essentially many planes of the material ‘graphene’ all layered up on top of each other, and is found in pencils; the ‘lead’ in your pencil is actually graphite, and it is these layers of carbon atoms sliding relatively easily over each other that allows you to write and draw quite easily.

Graphite is used in many nuclear reactors in the UK in the shape of enormous blocks, which can be over a metre in height, all stacked on top of each other and arranged into a large reactor core. Its purpose is to slow the neutrons in the core down, by acting as a physical barrier for the neutrons to bounce off, a little like billiard balls, so that they will react more easily with the nuclear fuel, producing energy for us to power our homes. 

Why is it radioactive?

Carbon has been selected as a fairly ‘neutron transparent’ material so that neutrons will bounce off and scatter away from the carbon atoms instead of being absorbed. This does not happen every time, however, and on occasion a neutron will be absorbed into the carbon atom, making the nucleus of the atom heavier and larger than it was previously. This can make the atom become unstable, as it can no longer physically sustain itself in a stable state, and so the atom will ‘decay’ by releasing some energy – in this instance, a radioactive carbon-14 atom will spit out an electron from the atom and transmute into nitrogen-14, which is a stable atom. Voila! This is the process of radioactive decay.

What do I actually do?

I spend a lot of time working in a laboratory with radioactive samples, taken from a nuclear reactor, wearing a white lab coat, goggles, layers of gloves, and working with tongs behind special shielding or in a glove box, like Homer Simpson. I also wear a dosimeter to record the amount of radiation I have received from the samples, so that I know I am well below safe levels for working. I then take these samples and place them in a specially designed tube furnace, and very carefully oxidise them using a gas flow of 1% oxygen to try and remove a good fraction of the surface radioactivity as a gas. The radioactive portion of this gas is then trapped and collected in a ‘bubbler system’, where the gas is forced to bubble up through a clever fluid, before it is taken away for analysis to determine how much radioactivity has been successfully removed. I can then use this data to make a reasoned judgment of how I might improve the process, by adjusting the temperature, for instance.

Going Further

More information about the array of Nuclear Engineering research in the School of MACE at the University of Manchester can be found at: http://www.mace.manchester.ac.uk/our-research/research-themes/nuclear-engineering/

A fairly detailed overview of ‘radioactive waste management’ around the world has been produced by the World Nuclear Association, and can be found at: http://world-nuclear.org/info/Nuclear-Fuel-Cycle/Nuclear-Wastes/Radioactive-Waste-Management/

A further insight into the role of the Nuclear Decommissioning Authority in the UK, working on behalf of the government and responsible for overseeing the clean-up of many UK nuclear power sites, can be gleaned from the following website: http://www.nda.gov.uk/what-we-do/

 

Body Broken?

by YPU Admin on June 12, 2013, Comments. Tags: Biophysics, Computer modelling, Physics, Research, and science

Introduction

Since before your birth you have interacted with the world via the physical form that is your body; but how much do you really know about it? Do you know how it works? What do your cells actually do? How do organs like your heart and brain function? What stops them from functioning, endangering or even ending your life? Can we prevent them from failing?

My name is Craig Testrow and I’m a Biophysicist; in other words, I solve biological problems by investigating the physics behind them, asking (and occasionally answering) questions like those above. My project is to build a computer model of the uterus, or womb, with the aim of preventing women from giving birth too soon, which can greatly harm their newborn baby.


In Depth...

I’m a physicist by training. At A-level I studied Maths, Physics, Chemistry and Further Maths. I then went on to do a physics degree at Manchester. But what business does a physicist have poking his nose into biology and medicine? Well, ultimately all biological and chemical systems are governed by the laws of physics. Let me give you an example; consider a heart cell. Such cells are the building blocks that make up the heart; if you understand those blocks, you can assemble them and understand the whole organ. This is where the physics comes in: we view the cell as a little electrical circuit.

 

An imbalance of charged calcium, sodium and potassium ions inside and outside of the cell creates a potential difference, forcing the ions to flow across its membrane in an attempt to balance the charge. This remarkably simple analogy of a cell to a circuit board works really well. We just apply all the familiar laws of circuits, like Ohm’s Law (V=IR) to our cells and find we can replicate the activity we witness in living systems on a computer. It is all the more amazing when you realise how incredibly complex the systems in our body actually are. But these complex systems are entirely dependent on simple, universal physical principles.

But why do we bother writing computer programs? Shouldn’t we spend our time with patients instead of fiddling around with all this code? Well, not if we want to help as many people as possible. Our computer models can perform thousands of simulations, with hundreds of variations in the time it takes to run a single traditional laboratory experiment; not to mention it’s cheaper and doesn’t require you to give up your organs so we can prod them with probes (well, not as often anyway). And on a purely numerical basis, a medical doctor might be able to treat 20 or 30 people a day; if successful, our research could be put into practice worldwide, directly helping thousands of people each day, millions every year.

There is a key point to be made here: people working outside of science and medicine often overlook the role of research in coming up with new knowledge and techniques, which are placed in the hands of doctors who go on to implement them. Cancers are treated on hospital wards, but they’re cured in the lab. That said, our work would be impossible without the efforts of experimental biologists providing us with raw data, and irrelevant without the dedication of medical staff on the front line; like links in a chain, we’re each dependent on the others for support.

Something I’ve learned while studying physics is that the well-trodden path is not necessarily the right one. Whichever subject interests you, be it science, medicine, or any other; take the time to ponder less conventional routes. If you are interested in medicine, consider a career in research; the scientist who cures cancer or eradicates HIV will secure their place in history.


Going Further

You might like to have a look at the following links if you are curious about physics, biophysics or medical research:

Undergraduate physics courses at Manchester. Includes lots of useful info, including views of current and previous students:

Postgraduate physics at Manchester, for when one degree just isn’t enough!

The Institute of Physics website

An introduction to biophysics and its importance as a field by the Biophysical Society

Topics covered in biophysics

Want to live forever? Dr. Aubrey de Grey of Cambridge thinks medical research will soon lead to immortality, by curing age-related diseases through regenerative biotechnology. Read more about the SENS Research Foundation.