Monday 29 April 2013

Surrey neutron star workshop

This is just a quick advert for a workshop we are holding at Surrey on neutron stars.  It's being part-funded by our local "Institute for Advanced Studies" (I didn't pick the name), which always requires as multidisciplinary a theme as possible, so on-topic areas include effectively anything that you think might relate to neutron stars, so very many areas of physics an astronomy could be relevant.  Maybe even people interested in studying the geometry of pasta might be interested.  

The deadline for submitting abstracts is tomorrow, so get your skates on if you'd like to attend and give a presentation.  Full details at the workshop website.

Friday 26 April 2013

Going to Florence

Every few years, there is a very generically-named international nuclear physics conference, which goes by the name "INPC" - or International Nuclear Physics Conference.  INPC'13 is being held in Florence, and the organisers have seen fit to accept my abstract for a talk.

I noticed earlier in the week that the full programme is up, so I downloaded it to see when I would be speaking.  I've not been to an INPC before, but I was aware that these are huge conferences by nuclear physics standards.   I see from the programme that during the parallel sessions, there are nine concurrent talks going on.  I'm not sure how that will play out for numbers in each of the sessions, and I guess I'll just have to see.  It at least doesn't appear that I am clashing with anything so very similar, so at least those few people who desperately want to see me talk will have no dichotomies.  Or trichotomies and so on.

I've never been to Florence before.  I hear it's nice.  It makes me think of this song by Zoot Money, which I know thanks to my dad's record collection.  It's clearly too obscure to have a YouTube entry, unfortunately, so the link is to Spotify.

Anyway, I'm very much looking forward to going.  The range of talks looks really good, and you can expect me to blog quite a bit from there.  I'll have a little time for sightseeing, so if there are any things you want to suggest that I see, please comment below

Sunday 21 April 2013

The REF is a ranker

There have been a couple of posts I've seen over the last few days about the REF: the system by which the UK government decides on a part of the funding it gives to UK universities.  Perhaps unsurprisingly, given that I choose to read the posts of these bloggers, I largely agree with the opinions of telescoper and to the left of centre.  There are some interesting comments on telecoper's post.  The chief protagonist makes some interesting points, but ultimately, the suggestion that because the submitted papers have been through peer review already means that the panel don't need to do that again make no sense to me.  In my area (nuclear physics), the acceptance rate in Physical Review, which is surely the toughest specialist journal to be accepted in, is around 80%.  Elsewhere - in other journals - I expect it is even higher so that extant journal peer review is utterly irrelevant when it comes to deciding whether peer reviewed papers submitted for the REF are so-called 4*, 3*, 2* or 1*.  Peer review in journals judges correctness more than quality. To the extent that any of the classifications make any sense, all published papers, that have been through peer review, would still need to be re-reviewed in full by the panel to decide on those categories.  As Peter says, this can't really happen properly.  I also agree with his feeling that panel members who have been told not to take where papers have been published into account will still take where they are published into account.  I have heard the opinions of enough people on previous RAE panels to believe that the rules will not be adhered to in that regard.

The protagonist also pointed out something I didn't know:  That the Computer Science community had asked for Google Scholar to be included in the citations information.  As things stand, only the Scopus citation data from Elsevier will be given to panels, and Google Scholar has been investigated but has been ruled out.  I guess that wouldn't much matter if all the different metric websites agreed with each other.  But do they?

I spent a little time this afternoon looking at the papers I have published since 2008 (the REF period, basically) and the citation information from the obvious different websites.  It is not necessarily the most representative sample of papers, but at least one relevant for the REF.  They were Google Scholar, Scopus (which the REF is using), ISI, and the individual website metric measurements.  Here is the graph of total citations since publication for the 25 papers I've published since 2008.  The vertical grid lines separate each paper, with the indicated bars showing the number of citations according to each website.

What can be said about the graph (or the data from whence it came)? In a perfect world, you would hope that for each paper, the number of citations would be identical for each website.  Obviously it is not, and that is not surprising, but is it worrying?  It's certainly noticeable that some papers have wildly different numbers of citations according to different sites.  Paper 7, the highest cited paper, has about twice as many with google scholar as with Scopus or ISI.  Google Scholar is usually the most comprehensive, including e.g. citations by theses published on institutional websites, yet sometimes ISI comes out with more hits (e.g. #19 in which ISI comes out top.  Scopus is very low here).  There are worrying things.  Paper #14 is my third highest cited thing according to Google Scholar, and that is correct, as far as I can tell, but Scopus, the systems paid for by the taxpayer to do the judgement, is not aware of the paper, despite it being published in a mainstream journal (Europhysics Letters).  There are plenty of other anomalies.  It's not perhaps as clear as it might be from the figure, but there are a few examples of where drastic differences are evident from the different websites.  I'm happy to send you my more detailed breakdown, if you want to check it out.



Tuesday 16 April 2013

Shape Coexistence

I'm on the train on the way back from my second conference trip to York in as many weeks.  This time, it was a specialist workshop on shape coexistence in nuclei.  Shape coexistence is a slightly strange name, given to a natural consequence of quantum mechanics that seems a bit counter-intuative, so has been given a name.

Objects of everyday size and scale typically have something that you can call a shape.  Footballs are spherical in most of the world, or prolate spheroids in the USA.  Eggs are oviform, breasts are mammiform, and so on.  Only, if you were to look closely, at an atomic level, at any macroscopic object, you'd see that the surface was not quite as solid as you thought, but an undulating border between atoms belonging to the object, and those not.

Down at the tiny level of atomic nuclei, the undulation is so intertwined with the nature of the nucleus, that the concept of shape breaks down.  Many nuclei don't just sit there being a specific shape, but undulate so that they are a sometimes spherical, sometimes stretched spheres, sometimes squashed spheres, and occasionally other shapes.  This is just quotidian quantum mechanics, but because it's counter-intuative, it's got its own name, and associated conferences.  To be fair, it's as good a theme to use to understand any part of nuclear physics as any other, as long as one understands why we consider it a particular topic.

There were a lot of interesting talks, covering nuclear states that simultaneously exhibit multiple shapes, from both experimental and theoretical points of view.  I gave a talk, and it invoked some mild disparagement from a fellow theorist, as theory talks always seem to do.  It's too bad my interlocutor had to depart for a train before the end of the session I was in as we never managed to have a good chat about it.

As ever, I think about adding a figure to a blog post as I finish writing.  Clearly, the term "shape coexistence" is used only amongst nuclear physicists, and not in other areas.  This is perhaps not too surprising, as nuclei are the only quantum objects that are within their own size for a few orders of magnitude, so if that's the scale at which the effect happens, then there's nothing else for it to happen to.  The picture is taken from a Cern Courier article about work by many of the people at the workshop, including its organiser, showing some of the different "co-existing" shapes in an isotope of lead.

Tuesday 9 April 2013

Solving the medical isotope problem

One of the nice things about this year's Institute of Physics nuclear physics conference is that we have a few attendees from universities which don't usually send people.  It seems, perhaps, that nuclear physics activity in the UK is growing, or at least that some of the more applied nuclear physicists are joining in community events.

Yesterday, I attended two interesting talks by people form such non-traditional universities;  Huddersfield and Cambridge (nice to be able call Cambridge a non-traditional university).  Both speakers were concerned with performing simulations of nuclear reactions induced by small-scale low-energy particle accelerators in order to produce medical isotopes.  One of the most important medical isotopes is technetium-99m (Tc-99m).  It is normally produced by taking molybdenum-99 from nuclear reactors, and letting that decay to technetium-99m.  The "m" means that the technetium is in an excited state, and it decays by X-ray emission.  By preparing a suitable technetium compound that targets particular parts of the body when ingested, the position of the emitted X-rays can be measured.

Through various reasons, including unplanned reactor shut-downs, the worldwide production of Tc-99m has decreased markedly.  The groups at Cambridge and Huddersfield are looking at new, non-reactor-based ways of producing it, and indeed other medical radionuclides.

The picture associated with this post is from a poster presented by Naomi Ratcliffe, from Huddersfield, available from the Huddersfield website.  It relates to some of the simulations of neutron yields that she presented in her talk.

Sunday 7 April 2013

York for the IoP conference

About this time of year every year, the Institute of Physics Nuclear Physics Group organises its national conference.  It's for everyone in the UK working on nuclear physics (mostly, but not exclusively with a bent towards academic as opposed to industrial aspects).  It's open to overseas attendees, too.  We usually invite a few overseas keynote speakers, and sometimes overseas applicants want to come and attend.  That's fine, as long as it fits in the conference venue, but the focus is on a national scale.

The location of the conference cycles between all the places where University nuclear groups are based, and this year we are in York.  Fortunately all the UK groups are based in pretty interesting places, except for my home institution, so I always get to travel somewhere more interesting than where I live at conference time.

The purpose of the conference is split into sharing the latest academic news and networking.  They probably both carry about equal weight.  Although we can keep up with each others' work by seeing what papers we publish in journals and the arXiv, there's nothing quite like being away from your desk,  and listening to people describe their work to get a good idea of what's going on.  On the social side, the conference is a great way to help build a sense of community in the UK groups.  Science research is sort-of international in scale, but also sort-of national.  At the basic level of science ideas, the community is worldwide, but part of research life is working within the organisational framework of your country, its institutions and funding mechanisms.  We spend some time together to help us act together as a community, and part of the conference will be a town meeting with representatives from the funding council STFC to talk through some of the political aspects of research.

Part of the networking and socialising will be in the form of visits to the pub in the evening, no doubt, and there is a conference banquet for the purpose of penalising the person to speak first in the morning after it.  I, fortunately, am speaking in the first morning, about the kinky lead phenomenon I blogged about before.

I decided to come up a bit early and book a separate hotel for a one-night holiday before the conference started.  At the top is a picture of me by York Minster, in deference to how tourists are expected to behave.