Convenient scheduling and a generous host meant that I was lucky enough to attend the Yukawa Institute for Theoretical Physics workshop on Nucleosynthesis and Evolution of Neutron Stars at Kyoto University, end of this month. The workshop featured observers, astro and nuclear theorists, and nuclear experimentalists, and was supported in part by IReNA. Was great to catch up with some colleagues' work on thermonuclear bursts, including with the remarkable NinjaSat satellite. Also lots of presentations and posters about identifying and investigating key nuclear reactions for thermonuclear bursts. I gave a talk covering X-ray binaries and focussing on new views of thermonuclear bursts, including some recent work with matching observations and numerical models.

I am extremely grateful to the organisers and also the Foundation for Promotion of Astronomy who supported my travel and local costs.

Labels: 2025, meetings

I'm about to go on leave for the holidays, but a couple of papers to note that just came out, that I had a little involvement with.

Zhi-Qiang You's paper "The birth mass function of neutron stars" addresses the problem that many of the objects we observe today have had a history of accretion that can significantly increase their mass, so it's a challenge to work backward and infer how they started. This initial mass distribution in turn encodes information about the formative supernova explosions and evolution up to that point. Zhi-Qiang's paper has now been accepted by Nature Astronomy.

Tao Fu's paper "A comprehensive study of type I (thermonuclear) bursts in the new transient SRGA J144459.2−604207" focusses on the remarkable burst behaviour of the 2024-discovered millisecond pulsar, observed with the Chinese Insight-HXMT and NASA's IXPE satellites. During a 2-week outburst this source exhibited 60 thermonuclear bursts, with remarkably consistent profiles and recurrence times. Such "clocked" bursters are key sources for comparison with numerical models. Tao's paper has now been accepted by ApJ.

Labels: 2024, papers

Had a great week at the Institute for Nuclear Theory in Seattle, WA while attending the IReNA-INT Joint Workshop on Thermal and Magnetic Evolution of Neutron Stars. This workshop brought together theoretical and observational astrophysicists, with nuclear experimenters and theorists, and covered a wide range of topics of relevance to understanding neutron stars. I kicked things off on Monday talking about some of the exciting new observations of thermonuclear bursts that have happened over the last couple of years.

I really like the INT's approach to bring researchers together in small, focussed workshops to help encourage progress. A relaxed schedule — with afternoons free for general discussion and pop-up talks — is ideal. And even though the in-person interactions are most valuable, the organisers encouraged on-line presentations and participation, which is mandatory IMO for modern meetings. (I'd presented twice before to INT workshops, but both times remotely). I really appreciate the support of IReNA which made my attendance possible.

Labels: 2024, meetings

Just got back from a wonderful visit to the International Space Science Insitute in Bern. A really productive 3 weeks, working with colleagues Maurizio Falanga (also ISSI Director) and Zhaosheng Li, also visiting from Xiangtan U.. Some good discussions about thermonuclear bursts and work with data from China's HXMT-Insight telescope.

Also spent plenty of time working on the beansp code and made some really significant improvements to the code, which hopefully should be reported soon in a paper.

It wasn't all work though and I inadvertently timed my visit to include ISSI's annual dinner at the lovely Bellevue Palace, a wonderful night. I also enjoyed two weekends of glorious (although cold) weather, biking through the Aare and Rhône valleys, and of course all the glorious food. Particular thanks to my ISSI hosts for making me feel at home!

Labels: 2024, visits

Had a fantastic time in Leiden this week attending the Extreme Matter in Extreme Stars, hosted by the always-brilliant Lorentz Center. The meeting sought to bring together neutron star theorists and observers, with nuclear physics theorists and experimenters, as well as people interested in gravitational-wave sources involving neutron stars. Really nice program with only a few review talks but plenty of opportunity for discussion and short "pop-up" talks, and great attendance by ECRs. To put our money where our mouths are we were tasked with writing a "white paper" or similar intended to bridge the information/assumption gaps between these various communities. A week is only enough to really make a start and so our work will continue remotely; stay tuned!

Labels: 2024, meetings

GOTO team members Tom Killestein and Lisa Kelsey have done an incredible job developing and managing our "flagship" outreach program, Kilonova Seekers, launched with great fanfare back in 2023. The project provides candidate transients detected by GOTO and asks users to play "spot the difference" in distingushing genuine transients (or source variability) from various kinds of artifacts that crop up in our differencing procedure. Tom & Lisa wrote up their work for MNRAS and the paper has now been published. Accompanying the paper were press releases from Portsmouth, Turku, Leicester and even Monash, the latter also acknowledging the contribution of Monash PhD student Sergey Belkin. Although it was not possible to include all our contributing volunteer scientists in the author list, they are acknowledged in the paper's appendix A; all 4.5 pages of them! Keep up the great work

Labels: 2024, outreach