Semi-empirical mass formula on the plane

I've just returned from a long trip away, to visit students on MPhys placement, attend a conference and discuss work with some people I am collaborating with (a phrase I still think of as meaning something sinister).  On the plane I watched a terrible film called Red Joan.  It sounded like it might be a decent enough spy thriller and Judy Dench's name lent it some respectability.  On-topic for me is that it featured someone (the eponymous hero, or antihero, Joan) who passed secrets about the UK's wartime and post-war atomic weapon secrets to the Russians.  There was one scene, supposedly dramatically showing people thinking about a physics problem, in which the camera focused on the pencil-and-paper working of one of the scientists, which showed the semi-empirical mass formula (see attached photo).  This is certainly something that was known in the late 40s, and the kind of thing that would have been used to give an idea of the energy release from nuclear fission, so credit to them for doing that research.  Given that I was on my way to a conference where I talked about the semi-empirical mass formula, it was a nice coincidence, and I took the photo of the screen on the back of the seat in front and used it in my talk, and here in this post.

HIAS conference photo

It's the last (half) day at the HIAS2019 conference today.  Just before the first session started (with some oldish results from RIKEN around the tin-132 isotope, they presented the obligatory group photo which was taken on Tuesday.  Here it is.  I'm in the back (as ever, being quite tall), wearing a blue hoodie, and a beard.  Next to me is ex-Surrey student Ed Simpson who laughed at me when I called my hoodie a "cardigan".  The photo can be clicked on to get a high resolution version.

HIAS-19

I'm in Canberra visiting some students on their MPhys Research Year placement, and also attending the HIAS-2019 conference (HIAS = Heavy-ion Accelerator Symposium).  The scientific topics cover any of the things that one can do at a heavy-ion accelerator which include the kind of reactions that I am interested in calculating, but also things like accelerator mass spectroscopy.  This is a very sensitive way of measuring the masses of individual isotopes in a sample of material.  One such application was presented by Dominik Koll who showed how to measure the abundance of Iron-60 which is a long-lived radioactive isotope generated in supernova explosions, and shot out into interstellar space, some of which then arrives on the Earth.  It turns out that it is currently raining down on Earth to the extent of a couple of atoms per square centimetre per year. 

European Few Body Conference

At The Univerity of Surrey we are hosting (and organising) the 24th European Few-Body Conference.  Its topics cross nuclear, atomic, and solid state physics;  any place where a many-body problem can be considered a few-body problem, with the resulting related set of mathematical techniques for solving them across the physics sub-fields.

Running a conference in ones own institution means competing with other day-job activities.  I have four MSc projects doing projects this summer who need meeting, and I only work on 4 weekdays, having a day with my children on Mondays.  So today is the first day I'll be able to attend all the sessions, and we've started with a talk on hyperons -- protons or neutrons in which one (or more) quarks have been replaced by strange quarks. 

On Monday, I thought I'd bring the kids along for the coffee break to see the conference.  They quite liked the lecture theatre chairs with the little desktops fitted into the armrests, though they do look a little bored in the picture I took that I've put in this post.  I'm presenting a poster tomorrow on the triple-alpha reaction -- work started by a BSc project student last year.

By the way; when I say above "we are [...] organising" I really mean that Natasha Timofeyuk is organising, and the rest of the committee are playing bit parts.  My bit is mainly sorting out the proceedings;  a job which is about to start getting busy, assuming anyone submits their papers.

The Thermal Syndicate Ltd

I'm on holiday this week in Deal, Kent, where I have been coming with my partner and kids, my brother's family, and my parents for the past few years for a week-long holiday in August.  We stat at a house belonging to a friend of my parents who is also a descendant of William Thomson, Lord Kelvin.  There's a lot of interesting reading matter in the house.  This year I've started with a history of a company called The Thermal Syndicate Ltd., erstwhile makers of fused quartz ware which was used for, amongst other things, chemical apparatus. 

The book was written for the company's 1956 50th Jubilee, and is clearly a corporate exercise, with no author mentioned.  It is a fairly sober retelling of the company's history.  It's sort-of interesting to read about how the company was founded, with a combination of money and connections being the key features.  The scientific aspects of it were interesting -- not just the techniques developed to make the very high-temperature-resistant glass, but also the scientific culture of the time married with the commercial aspects.  

The sober account of the company contains what pass for a couple of anecdotes, including an "imagined conversation" in local (Newcastle) dialect of the speculation of what took place in the Wallsend factory, as in the attached picture, which reads

   'Whaat d'them blokes dee at Waalsend Laboratories?

    They analiise things for Thormal Synnicate.

    What d' the Synnicate myek?

    They myek things for Waalsend Laboratories t' analiise!'

Aside from that, I also enjoyed some of the pictures of industrialists of Edwardian industrialists, which I have added at the top of this post.

Happy 100th Birthday Margaret Burbridge!

Today, 12th August 2019, is the 100th birthday of Margaret Burbridge.  She is a British-American astrophysicist who is jointly responsible for the idea that stars are giant nuclear fusion reactors.  This started the whole field of nuclear astrophysics, and is canonical enough to be taught to undergraduates.  In fact, we (at Surrey) have a degree programme called Physics with Nuclear Astrophysics, which we wouldn't have if not for Prof (emeritus) Burbridge.  Happy Birthday!

The picture is from the Wikipedia article about her, and shows her in 1976 winning a Woman of the Year award.

Thursday at #UNTF2019

#UNTF2019 continues today after yesterday's talks, poster session, and conference dinner, with two sessions in the morning, followed by the end of the conference and lunch.  Here's a summary of the first session's first two talks (with the third being designated for attendees-eyes only)

Toby Wright from Manchester started the morning with a comprehensive survey of all kinds of nuclear data being collected at the n_TOF (neutron time-of-flight) facility at CERN.  This includes things like neutron absorption cross sections and fission data, which provide useful input for applications - particularly nuclear reactors. Toby presented a lot of results of data, improving on older measurements and evaluations

The second talk had the title "Robots used to mitigate nuclear disasters", with a discussion of exactly that -- how robots can be made and used in nuclear disasters.  They need to be very radiation-resistant, for examples, which has consequences for the design.  Also, you can't go in and fix it if it has a small problem, so it has to be very reliable.  Ideally you'd like to communicate with it wirelessly, but nuclear reactors tend to be heavily shielded.  The environment (radiation aside) can be pretty hazardous; flooding, fallen masonry etc.  All-in-all, quite a challenge to the robot builder. We had
The talk covers robots used historically;  the "RadRobot", "RedBot", and "WorkHorse" used at Three Mile Island; At Chernobyl there is a museum dedicated to the robots used there, though full details of the ~60 robots used there have been lost.  The most succssful robot used there, "MoBot" was destroyed when a helicopter accidentally dropped it.  Some robots used, such as converted tanks and bulldozers, broke down very quickly due to the environmental hazards.   Some years after the initial disaster further more advanced robots were sent in to assess the continuing status of the ruined reactor;   The robots used at Three Mile Island and Chernobyl were built reactively after the disasters, while in Fukushima there were a number of robots built in advance to be used in case of problems (as well as to routinely monitor).  Unfortunately, they were not very usable in Fukushima because the robot projects had been defunded and the robots left in cupboards, lacking maintenance, and lacking expertise of the staff who had left or moved on to other projects.  Instead, "Packbots" and "Warrier" robots were bought off the shelf from the US and deployed.  They weren't radiation-hardened but were well-developed in other technological areas.  Many other robots were then deployed -- e.g. the "quince" which could go up stairs and over rubble, the "RaBot", a radiation-hardened robot which could handle very high radiation doses (10,000 Sv per hour).

The talk ended with a couple of robots designed for the future;  Honda's E2-DR and the Centauro from Italy.  We were treated to a video of the E2-DR which looks a little like it's trying to get back from a conference dinner after one too many drinks: