• Question: What was the last project/experiment that you worked on, and what did you find out from this???

    Asked by anon-232126 to Mark, Liam, Laura, Kasia, Gina, Felix on 12 Nov 2019.
    • Photo: Laura Sinclair

      Laura Sinclair answered on 12 Nov 2019:

      My PhD project was an international collaboration in Japan. The work involved smashing a heavy beam into a light target to create lots of fragments. To get the fragments we wanted we then used special magnetics and electrical fields, then we had special detectors to collect the fragments.

      It took many years of analysing the data, but we observed some things for the first time. Atoms are made up of protons, neutrons and electrons but there are only certain configurations allowed by the laws of nature. For example, you have Carbon-12 which has six protons and six neutrons, but there is C-11 (6 protons and 5 neutrons), C-13 (6 protons and 7 neutrons), C-14 and so on. At a certain points you can’t add or take away anymore neutrons, and part of nuclear physics is investigating this to understand the laws of physics better.

      At present there have been approximately 3500 configurations observed. For my PhD experiment we observed a couple of new configurations for the very first time, which I thought was very cool!

      Also, we have radioactive atoms that decay to become stable. However, different atoms decay at different rates. For example the medical isotope Tc-99m has a half-life of 6 hours. This means if you have 100 MBq (a measure of radioactivity) of Tc-99m at 9am by 3pm there will only be 50 MBq, then by 9pm there will be 25 MBq and so on. In my experiment I measured the half-lives of a few radionuclides for the first time. This was published in a couple of papers.

      In addition to learning lots of new science, I got to learn a new culture whilst living in Japan. It was an amazing experience.

    • Photo: Mark Johnson

      Mark Johnson answered on 12 Nov 2019:

      For my PhD project I worked on an experiment at CERN, an international lab on the French-Swiss border. Our experiment (called ALPHA) is designed to trap small numbers of atoms made out of antimatter. Antimatter is like a mysterious ‘mirror image’ of the normal matter that makes up everything around us on Earth. Whenever it comes into contact with normal matter, antimatter will annihilate and disappear in a flash of radiation. Usually, this makes it really difficult to study any type of antimatter for more than a fraction of a second. In 2010, our experiment was the first to ever trap antihydrogen, using a special arrangement of magnets and a vacuum better than outer space!

      Back in 2016-2017, I played a small part in measuring the ‘colour’ of antihydrogen, by measuring one of the specific frequencies of light that it can interact with. This was the first time anyone had ever seen a ‘spectral line’ in antimatter before, and it was super exciting to play a small role in such a big discovery. When we announced our results, they even appeared in the New York Times, on BBC News and on the front page of Reddit!

    • Photo: Liam Gaffney

      Liam Gaffney answered on 13 Nov 2019:

      I am always working or contributing to lots of smaller projects, but the last big one that I played a major role in was to build a new experiment at CERN. We took an old MRI scanner from a hospital in Australia and transported it across the world to Geneva in Switzerland. The plan was to recycle the big magnet that inside these scanners to do nuclear physics.
      As part of a team from the UK, we stripped it down, created a big vacuum chamber inside and put various detectors and target foils in there. When we sent the high energy beam in, the products from the nuclear reactions were bent by the magnetic field and we could basically use it like a big camera to reconstruct what was happening.
      We learned all about what happens if you add one extra neutron to heavy mercury isotopes, which helps us to understand how the heaviest elements are created in astrophysical events like exploding stars and black hole collisions.

    • Photo: Felix Warren

      Felix Warren answered on 15 Nov 2019:

      My last placement was working on a device known as HIVE(Heating by Induction to Verify for Extremes) that uses a magnetic coil to heat metallic samples to extreme temperatures all within a vacuum chamber. While I was there we ran two experiment one with special liquid called alumina nano fluid which is pure water with minuscule spheres of alumina in it, we where testing it as a coolant seeing how well it would absorb and carry heat out of HIVE. The other experiment I helped with involved some tungsten disks, they had all been cracked in the same way so we heated them to around 800c and used special cameras to watch how they deformed and broke under the heat.

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