New dwarf galaxy candidates in the sphere of influence of the Sombrero galaxy

Abstract

We report the discovery of 40 new satellite dwarf galaxy candidates in the sphere of influence of the Sombrero galaxy (M104) the most luminous galaxy in the Local Volume. Using the Subaru Hyper Suprime-Cam, we surveyed 14.4 square degrees of its surroundings, extending to the virial radius. Visual inspection of the deep images and GALFIT modelling yielded a galaxy sample highly complete down to $M_g\sim -9$ ($L_g\sim 3\times 10^5{L}_{\odot }$) and spanning magnitudes $-16.4<M_g<-8$ and half-light radii $50pc<r_e<1600pc$ assuming the distance of M104. These 40 new, out of which 27 are group members with high confidence, double the number of potential satellites of M104 within the virial radius, placing it among the richest hosts in the Local Volume. Using a Principle Component Analysis (PCA), we find that the entire sample of candidates consistent with an almost circular on-sky distribution, more circular than any comparable environment found in the Illustris TNG100-1 simulation. However the distribution of the high probability sample is more oblate and consistent with the simulation. The cumulative satellite luminosity function is broadly consistent with analogues from the simulation, albeit it contains no bright satellite with $M_g<-16.4$ ($L_g\sim 3\times 10^8{L}_{\odot }$), a $2.3\sigma$ occurrence. Follow-up spectroscopy to confirm group membership will begin to demonstrate how these systems can act as probes of the structure and formation history of the halo of M104.

16 pages, 11 figures, accepted to MNRAS

References in corpus (39)

• The EAGLE project: Simulating the evolution and assembly of galaxies and their environments
• Introducing the Illustris Project: Simulating the coevolution of dark and visible matter in the Universe
• The Completed SDSS-IV extended Baryon Oscillation Spectroscopic Survey: Cosmological Implications from two Decades of Spectroscopic Surveys at the Apache Point observatory
• The Pantheon+ Analysis: Cosmological Constraints
• Updated Nearby Galaxy Catalog
• A Vast Thin Plane of Co-rotating Dwarf Galaxies Orbiting the Andromeda Galaxy
• Dark Matter Substructure in Numerical Simulations: A Tale of Discreteness Noise, Runaway Instabilities, and Artificial Disruption
• Galaxy Groups within 3500 km s${}^{-1}$
• The spatial distribution of the Milky Way and Andromeda satellite galaxies
• Two Planes of Satellites in the Centaurus A Group
• The Milky Way's Disk of Classical Satellite Galaxies in Light of Gaia DR2
• Discs of Satellites: the new dwarf spheroidals
• Wide-Field Survey of Dwarf Satellite Systems Around 10 Hosts in the Local Volume
• The Dragonfly Nearby Galaxies Survey. III. The Luminosity Function of the M101 Group
• An Ultra Compact Dwarf around the Sombrero galaxy (M104): the Nearest Massive UCD
• The coherent motion of Cen A dwarf satellite galaxies remains a challenge for $\Lambda$CDM cosmology
• Luminosity Functions and Host-to-Host Scatter of Dwarf Satellite Systems in the Local Volume
• Vast planes of satellites in a high resolution simulation of the Local Group: comparison to Andromeda
• Testing the two planes of satellites in the Centaurus Group
• Tracing satellite planes in the Sculptor group: I. Discovery of three faint dwarf galaxies around NGC 253
• Dwarf Galaxy Discoveries from the KMTNet Supernova Program I. The NGC 2784 Galaxy Group
• Newly discovered dwarf galaxies in the MATLAS low density fields
• Evolution of galactic planes of satellites in the EAGLE simulation
• The Lopsidedness of Satellite Galaxy Systems in $\Lambda$CDM simulations
• Pecular velocities of galaxies in the Leo Spur
• A weak lensing estimate from GEMS of the virial to stellar mass ratio in massive galaxies to z~0.8
• And In The Darkness Unbind Them: High-Resolution Simulations of Dark Matter Subhalo Disruption in a Milky Way-like Tidal Field
• Flattened structures of dwarf satellites around massive host galaxies in the MATLAS low-to-moderate density fields
• On the Co-Orbitation of Satellite Galaxies Along the Great Plane of Andromeda: NGC 147, NGC 185, and Expectations from Cosmological Simulations
• The abundance of dwarf galaxies around low-mass giants in the Local Volume
• The orientation of planes of dwarf galaxies in the quasi-linear Universe
• Distance and mass of the M104 (Sombrero) group
• The lopsided distribution of satellites of isolated central galaxies
• The Origin of Lopsided Satellite Galaxy Distribution in Galaxy Pairs
• New dwarf galaxy candidates in the sphere of influence of the Local Volume spiral galaxy NGC2683
• Classifying the satellite plane membership of Centaurus A's dwarf galaxies using orbital alignment constraints
• Lopsided Satellite Distributions around Isolated Host Galaxies in a LCDM Universe
• Early-type galaxies in the Antlia Cluster: global properties
• Tracing the Giant Outer Halo of the Mysterious Massive Disk Galaxy M104 I. Photometry of the Extended Globular Cluster Systems

Cited by in corpus (4)

• IFUM Integrated Field Spectroscopy of Ten M104 Satellite Galaxy Candidates
• An LBT view of the co-rotating group of galaxies around NGC 2750: Deep imaging and new satellite candidates
• Galaxies OBserved as Low-luminosity Identified Nebulae (GOBLIN): a catalog of 43,000 high-probability dwarf galaxy candidates in the UNIONS survey
• Globular clusters in M104: Tracing kinematics and metallicities from the centre to the halo