67 citations · 236 across the 20 of their papers we have counts for
20 papers
Stellar streams around dwarf galaxies are observationally rare in the local Universe
Joanna D. Sakowska, David Martíınez-Delgado, Sarah Pearson +6
The frequency and properties of stellar streams around dwarf galaxies remain observationally under-explored. Building a statistically significant sample is challenging because dwar…
Discovery of an extremely narrow trail-like feature crossing the Veil Supernova Remnant in deep amateur observations
David Martinez-Delgado, Jan-Niklas Pippert, Miguel A. Perez-Torres +9
We report the discovery of an extremely narrow and highly collimated gaseous trail-like structure crossing the eastern region of the Veil Nebula (Cygnus Loop). The feature was firs…
Andromeda XXXVI: discovery of a new ultra-faint dwarf galaxy towards M31
Joanna D. Sakowska, David Martínez-Delgado, Michelle L. M. Collins +4
We present deep imaging of Andromeda XXXVI (And XXXVI), a dwarf galaxy discovered through visual inspection of the Pan-Andromeda Archaeological Survey, using observations obtained…
A stellar stream around the spiral galaxy Messier 61 in Rubin First Look imaging
Aaron J. Romanowsky, David Martínez-Delgado, Giuseppe Donatiello +2
We present the first stellar stream discovered with the Vera C. Rubin Observatory, around spiral galaxy M61 (NGC 4303) in Virgo First Look imaging. The stream is narrow, radially-o…
Stellar streams around dwarf galaxies in the Local Universe
Joanna D. Sakowska, David Martínez-Delgado, Sarah Pearson +6
While mergers between massive galaxies and their dwarf satellites are well studied, the properties of dwarf - dwarf satellite mergers are not well constrained. Stellar streams trac…
A Pearl in the Shell: an ultra-compact dwarf within the tidal debris surrounding spiral galaxy NGC 7531
David Martínez-Delgado, Aaron J. Romanowsky, Yimeng Tang +7
Stellar substructures within tidal debris preserve information about their progenitor galaxies' properties, offering insights into hierarchical mass assembly. We examine a compact…
Stellar tidal streams around nearby spiral galaxies with deep imaging from amateur telescopes
David Martinez-Delgado, Michael Stein, Joanna D. Sakowska +26
Tidal interactions between massive galaxies and their satellites are fundamental processes in a Universe with L-Cold Dark Matter cosmology, redistributing material into faint featu…
Extragalactic Stellar Tidal Streams: Observations meet Simulation
Juan Miro-Carretero, Maria A. Gomez-Flechoso, David Martinez-Delgado +11
According to the well established hierarchical framework for galaxy evolution, galaxies grow through mergers with other galaxies and the LambdaCDM cosmological model predicts that…
Three Quenched, Faint Dwarf Galaxies in the Direction of NGC 300: New Probes of Reionization and Internal Feedback
D. J. Sand, B. Mutlu-Pakdil, M. G. Jones +18
We report the discovery of three faint and ultra-faint dwarf galaxies -- Sculptor A, Sculptor B and Sculptor C -- in the direction of NGC 300 (D=2.0 Mpc), a Large Magellanic Cloud-…
Extragalactic Stellar Tidal Streams in the Dark Energy Survey
Juan Miro-Carretero, David Martinez-Delgado, Maria A. Gomez-Flechoso +7
Stellar tidal streams are a key tracer of galaxy evolution and have the potential to provide an indirect means for tracing dark matter. For the Local Group, many diffuse substructu…
Tracing satellite planes in the Sculptor group: II. Discovery of five faint dwarf galaxies in the DESI Legacy Survey
David Martinez-Delgado, Michael Stein, Marcel S. Pawlowski +5
Although substantial progress has been made in reconciling LCDM simulations with the observed abundance and distribution of satellite galaxies, important tensions persist. Studying…
Pisces VII/Triangulum III -- M33's second dwarf satellite galaxy
Michelle L. M. Collins, Noushin Karim, David Martinez-Delgado +6
Pisces VII/Triangulum III (Pisc~VII) was discovered in the DESI Legacy Imaging Survey and was shown to be a Local Group dwarf galaxy with follow-up imaging from the 4-m Telescopio…
A giant umbrella-like stellar stream around the tidal ring galaxy NGC 922
David Martinez-Delgado, Santi Roca-Fabrega, Juan Miro-Carretero +6
Tidal ring galaxies are observed rarely in the local universe due to their intrinsically transient nature. The tidal ring structures are the result of strong interactions between g…
Pegasus V -- a newly discovered ultra-faint dwarf galaxy on the outskirts of Andromeda
Michelle L. M. Collins, Emily J. E. Charles, David Martínez-Delgado +5
We report the discovery of an ultra-faint dwarf in the constellation of Pegasus. Pegasus~V (Peg~V) was initially identified in the public imaging data release of the DESI Legacy Im…
Once in a blue stream: Detection of recent star formation in the NGC 7241 stellar stream with MEGARA
David Martinez-Delgado, Santi Roca-Fabrega, Armando Gil de Paz +23
In this work we study the striking case of a narrow blue stream around the NGC 7241 galaxy and its foreground dwarf companion. We want to figure out if the stream was generated by…
Tracing satellite planes in the Sculptor group: I. Discovery of three faint dwarf galaxies around NGC 253
David Martinez-Delgado, Dmitry Makarov, Behnam Javanmardi +7
In the last years, a new generation of large-scale imaging surveys have probed wide field regions around some nearby galaxies at unprecedented low surface brightness regime (~28.0-…
A feather on the hat: Tracing the giant stellar stream around the Sombrero galaxy
David Martinez-Delgado, Javier Roman, Denis Erkal +7
Recent evidence of extremely metal-rich stars found in the Sombrero galaxy (M104) halo suggests that this galaxy has undergone a recent major merger with a relatively massive galax…
Hidden depths in the local Universe: The Stellar Stream Legacy Survey
David Martinez-Delgado, Andrew P. Cooper, Javier Roman +26
Mergers and tidal interactions between massive galaxies and their dwarf satellites are a fundamental prediction of the Lambda-Cold Dark Matter cosmology. These events are thought t…
Pisces VII: Discovery of a possible satellite of Messier 33 in the DESI Legacy Imaging Surveys
David Martinez-Delgado, Noushin Karim, Emily J. E. Charles +5
We report deep imaging observations with DOLoRes@TNG of an ultra-faint dwarf satellite candidate of the Triangulum galaxy (M33) found by visual inspection of the public imaging dat…
Mirach's Goblin: Discovery of a dwarf spheroidal galaxy behind the Andromeda galaxy
David Martinez-Delgado, Eva K. Grebel, Behnam Javanmardi +9
It is of broad interest for galaxy formation theory to carry out a full inventory of the numbers and properties of dwarf galaxies in the Local Volume, both satellites and isolated…