Modern time-domain optical surveys are discovering supernovae at a dramatically increased rate compared to the past. Among them are many rare and peculiar events that fall outside the standard supernova (SN) classes. This poses serious challenges to traditional SN taxonomy, requiring a rewrite of the historical classification scheme. SN types are currently defined according to their observational properties. A long-standing goal of SN classification is to associate observationally-defined classes with specific explosion mechanisms and progenitor stars. However, it is still unclear if the diversity of observed SN classes is predominantly caused by different progenitor channels, explosion mechanisms, binary-star interaction, or properties of the explosion environment. For some unusual transients, the mechanism that lead to the stellar explosion (thermonuclear or core collapse) remains ambiguous. While for other events, an open question remains about whether a terminal SN explosion even occurred or not. Next-generation surveys such as the Large Synoptic Survey Telescope (LSST) will compound this classification problem by discovering hundreds of thousands of transient events per year, many of which will push the boundaries of our observationally-defined SN classes. Our goal for this symposium is to bring the supernova and transient community together to discuss the most important and exciting challenges in SN research to understand how and why stars explode as they do, as well as foster collaboration and develop new techniques for classification in the modern SN era. We will organize the symposium with the aim of promoting equity between junior and senior scientists, native and non-native English speakers, as well as striving for gender, race and geographical diversity in line with the supernova community.

List of topics covered:

· Current surveys and the approaching LSST era: classification criteria for new types of stellar transients and SNe.

· Traditional SN explosions: new observational and theoretical insights for thermonuclear and core-collapse events.

· Peculiar explosions from massive stars: interacting SNe, SN impostors, sub- and superluminous SNe.

Programme

• New SN surveys
• SN classification
• Type Ia SN diversity
• Core-collapse SN diversity
• Ejecta-CSM Interacting Supernovae
• Extreme stellar explosions

Invited speakers

• J. Anderson (ESO)
• F. Bianco (New York University)
• M. Drout (Carnegie Observatories)
• N. Elias-Rosa (INAF)
• M. Fraser (University College Dublin)
• J. Groh (Trinity College Dublin)
• C. Inserra (University of Southampton)
• E. Ishida (Université Blaise Pascal)
• S. Sim (Queen's University Belfast)
• M. Strizinger (Aarhus University)
• F. Taddia (Stockholm University)
• S. Taubenberger (Max Planck Institute for Astrophysics)

Scientific organisers

• MariaTeresa Botticella (INAF, Italy)
• Kate Maguire (Queen's Univ. Belfast, United Kingdom)
• Christina Thone (Instituto de Astrofisica de Andalucia, Spain)
• Paul Crowther (the University of Sheffield)
• Seppo Mattila (University of Turku, Finland)
• Andrea Pastorello (INAF, Italy)
• Simon Prentice (Liverpool John Moores University)
• Stephen Smartt(Queen's Univ. Belfast, United Kingdom)

Contact
botticella @ na.astro.it, kate.maguire @ qub.ac.uk, andrea.pastorello @ oapd.inaf.it