Special Session SS43  25 June 2025

Novae: From Accretion to Post-Eruption Phenomena

Aims and scope

The study of novae and cataclysmic variables (CVs) provides crucial insights into a wide range of astrophysical processes. In particular, as members of the accreting white dwarf binaries, these systems help us to understand binary interaction, the common envelope phase, white dwarf evolution and accretion processes.

During eruption, novae are observed across the full range of the electromagnetic spectrum:

  • the Galactic recurrent nova, RS Oph, has been observed with > GeV emission
  • gamma-ray emission is identified from nearby novae resulting from interaction of the nova ejecta with circumstellar material
  • the exposed nuclear burning on the surface of the white dwarf is captured through X-ray emission during the super-soft source phase
  • the first ever X-ray flash was captured by eROSITA prior to an optical nova eruption in 2022
  • an incredible amount of optical and UV data has been harvested, including huge contributions from amateur astronomers, covering both the visible brightening and subsequent decline of the eruption, in addition to resolving associated nova shells
  • infrared observations unveil dust formation
  • and radio emission captures the late-time evolution of the nova light curve and the evolving remnant.
A number of novae have exhibited signs of non-relativistic jets and novae enrich the interstellar medium with carbon, oxygen, nitrogen and lithium. At a larger scale, a proportion of novae (and CVs) have been found to host nova shells, with a number of recurrent novae recently being found to be surrounded by greatly extended nova super-remnants.

And at longer scales, recurrent novae can provide the mechanism for growing a WD towards the Chandrasekhar limit, primed to explode as type Ia supernovae, showcasing the role of novae in cosmological research.

This Special Session aims to showcase to a large audience the cutting edge of panchromatic nova and cataclysmic variable observations and associated theoretical modelling, encompassing the huge wealth of multiwavelength (from VHE gamma-rays to radio) and high cadence data (be that photometry, spectroscopy, polarimetry, and resolved imaging) collected of novel and well-investigated systems, including photometry and spectra acquired by amateur observers around the world.

And opportunely, the famous Galactic recurrent nova, T Coronae Borealis, is predicted to erupt in the coming year: such a once-in-a-lifetime event occurring prior to or even during the week of EAS would excitingly lead to many new results and generate huge intrigue from the wider astrophysical community!

[Image credit: NASA/CXC/M.Weiss.]

Programme

Date - Wednesday 25th June

Below is a preliminary programme for the Special Session - the exact programme is to be determined.

All contributed talks are scheduled for 12 minutes plus an additional 3 minutes for questions. Short poster talks will be presented during a single 10-15 minute slot.

  • Session 1: Introductory Talks on Novae and CVs
  • Session 2: High Energy Observations
  • Session 3: Recurrent Novae, Remnants and the Link to Type Ia Supernovae

Invited speakers

  • Anna Francesca Pala (European Southern Observatory, Germany)

Scientific organisers

  • Michael Healy-Kalesh, (Friedrich-Alexander-Universität Erlangen-Nürnberg, Germany; chair)
  • Matt Darnley, (Liverpool John Moores University, UK; co-chair)
  • Yael Hillman, (Azrieli College of Engineering, Jerusalem; co-chair)
  • Éamonn Harvey, (UK Astronomy Technology Centre, UK)

Contact

For any queries regarding the session, please contact Michael Healy-Kalesh (M.W.HealyKalesh @ ljmu.ac.uk) and Matthew Darnley (M.J.Darnley @ ljmu.ac.uk).

Updated on Tue Apr 15 11:04:05 CEST 2025
European Astronomical Society