The ultra-low surface brightness universe

A RAS Specialist Discussion Meeting organised by *David Valls-Gabaud (Cambridge); Jonathan.Davies (Cardiff)*Contact: david.valls-gabaud@obspm.fr Due to the limitations of current astronomical instrumentation and data reduction techniques, the Ultra-Low Surface Brightness (ULSB) universe – which lies over two orders of magnitude below that of the sky background – is the last niche that remains to be explored in observational parameter space. Yet, the first pioneering observations reveal a wealth of astrophysical objects whose properties appear to be entirely different from those at brighter levels. This meeting will review the new observations, the first models which attempt to understand the nature of these objects, and the prospects for further progress using both ground- and space-based instruments. MORNING SESSION (09:50-13:00) – CHAIR JONTHAN DAVIES09:50 David Valls-Gabaud and Jonathan Davies
Welcome and introduction10:00 Roberto Abraham (Toronto)
Exploring the low surface brightness Universe10:30 Ignacio Trujillo (IAC)
Frontiers in the low surface brightness Universe: the 10m telescopes perspective10:45 Reynier Peletier (Groningen)
The Fornax deep survey11:00 Pierre-Alain Duc (Strasbourg)
Probing the mass assembly of galaxies with deep imaging. Input from MATLAS and the NGVS11:15 Vasily Belokurov (IoA/Cambridge)
Ultra-faint dwarf satellites of the Milky Way - the lowest surface brightness systems in the Universe11:30 Sugata Kaviraj (Hertfordshire)
Studying the fundamental minor-merger process using ultra low-surface-brightness imaging11:45 Tahlia De Maio (U Florida)
Ejected but not forgotten: Intracluster light in massive halos12:00 Mohammad Akhlaghi (CRAL/Lyon)
Noise-based detection of low surface brightness features12:15 Dan Prole (Cardiff)
Automated searches for low surface brightness structures 12:30 Lunch

AFTERNOON SESSION (13:30 -15:30) - CHAIR DAVID VALLS-GABAUD13:30 Dennis Zaritsky (Steward/Arizona) – invited speaker
An abundance of ultra-diffuse galaxies in DESI preimaging data14:00 Joop Schaye (Leiden)
The filaments of the cosmic web at low surface brightness14:15 Marta Silva (Groningen)
Probing the low surface brightness universe with line intensity mapping14:30 Carlos Frenk (ICC/Durham)
Predictions from LCDM cosmological simulations14:45 Nicola Amorisco (MPA/Garching)
Most ultra-diffuse galaxies are low surface brightness 'normal' dwarfs15:00 Rafael Guzman (U Florida)
Exploring the low surface brightness universe with microsatellites15:15 Lee Spitler (Macquarie/AAO)
The Australian Space Eye15:30 Tea Poster:Michael Stein, Dominik J. Bomans, R.-J. Dettmar (Bochum)
"Ultralow surface brightness galaxies with HST"