A huge range of transient behaviour has been attributed to magnetars - highly magnetised neutron stars. In some cases, natal magnetars are invoked to explain extended or additional energy injection, for example in superluminous supernovae, ultra long gamma-ray bursts and short gamma-ray bursts from binary neutron star mergers. In others, such as fast blue optical transients, they are a possible explanation for the rapid rise and decay of their light-curves, which are inconsistent with regular core-collapse models. The extreme magnetospheres of magnetars are also a promising environment for producing luminous electromagnetic emission in the form of giant flares and fast radio bursts (FRBs) - now supported by the detection of FRBs from a Galactic magnetar.

The exact connection between our Galactic magnetars - of which approximately 30 are known - with those invoked to explain extreme transients, is still unclear. How different are magnetars formed by superluminous supernovae or by some GRBs, or those emitting FRBs, from magnetars we observe in our Galaxy? Are they the extremes of the same population? What is the distribution of neutron star spins and magnetic field strengths at birth, how does this evolve and what are the observational signatures of the energy dissipation? How are the extreme magnetic fields produced, what progenitors and initial conditions are required, and how can we obtain answers to these questions and more through studying their multi-wavelength emission, Galactic environments and associated supernova remnants?

In this lunch session, we will bring together Galactic and extragalactic communities to bridge the gap in magnetar astrophysics. We will review the latest theoretical and observational work on Galactic magnetars, telling us about their formation and properties. We will then discuss their role across a spectrum of extreme extragalactic transients, in the contexts of both modelling and observation, and the further advances in understanding that can be made with new and upcoming facilities.

Programme

This session will focus on the origin, properties and role of magnetars, including the theory and observation of,

• Galactic magnetars
• Flares, giant flares and fast radio bursts
• Engine-driven transients (GRBs, SLSNe, FBOTs)

Invited speakers

• Francesco Coti Zelati (ICE-CSIC)
• Jason Hessels (Anton Pannekoek Institute of Astronomy, University of Amsterdam)
• Ben Gompertz (University of Birmingham)

Scientific organisers

Ashley Chrimes (Radboud University), Andrew Levan (Radboud University), Roberto Turolla (University of Padua), Nanda Rea (ICE-CSIC), Antonia Rowlinson (University of Amsterdam), Joe Lyman (University of Warwick), David O'Neill (University of Warwick), Klaas Wiersema (Lancaster University), Sumedha Biswas (Radboud University), Nicola Gaspari (Radboud University)

Contact

a.chrimes(at)astro.ru.nl