The Astrophysical Journal (Jan 2024)
A Search for Faint Resolved Galaxies Beyond the Milky Way in DES Year 6: A New Faint, Diffuse Dwarf Satellite of NGC 55
- M. McNanna,
- K. Bechtol,
- S. Mau,
- E. O. Nadler,
- J. Medoff,
- A. Drlica-Wagner,
- W. Cerny,
- D. Crnojević,
- B. Mutlu-Pakdıl,
- A. K. Vivas,
- A. B. Pace,
- J. L. Carlin,
- M. L. M. Collins,
- P. S. Ferguson,
- D. Martínez-Delgado,
- C. E. Martínez-Vázquez,
- N. E. D. Noel,
- A. H. Riley,
- D. J. Sand,
- A. Smercina,
- E. Tollerud,
- R. H. Wechsler,
- T. M. C. Abbott,
- M. Aguena,
- O. Alves,
- D. Bacon,
- C. R. Bom,
- D. Brooks,
- D. L. Burke,
- J. A. Carballo-Bello,
- A. Carnero Rosell,
- J. Carretero,
- L. N. da Costa,
- T. M. Davis,
- J. De Vicente,
- H. T. Diehl,
- P. Doel,
- I. Ferrero,
- J. Frieman,
- G. Giannini,
- D. Gruen,
- G. Gutierrez,
- R. A. Gruendl,
- S. R. Hinton,
- D. L. Hollowood,
- K. Honscheid,
- D. J. James,
- K. Kuehn,
- J. L. Marshall,
- J. Mena-Fernández,
- R. Miquel,
- M. E. S. Pereira,
- A. Pieres,
- A. A. Plazas Malagón,
- J. D. Sakowska,
- E. Sanchez,
- D. Sanchez Cid,
- B. Santiago,
- I. Sevilla-Noarbe,
- M. Smith,
- G. S. Stringfellow,
- E. Suchyta,
- M. E. C. Swanson,
- G. Tarle,
- N. Weaverdyck,
- P. Wiseman,
- DES & DELVE Collaboration
Affiliations
- M. McNanna
- ORCiD
- Department of Physics, University of Wisconsin-Madison , 1150 University Avenue, Madison, WI 53706, USA ; [email protected]
- K. Bechtol
- ORCiD
- Department of Physics, University of Wisconsin-Madison , 1150 University Avenue, Madison, WI 53706, USA ; [email protected]
- S. Mau
- ORCiD
- Department of Physics, Stanford University , 382 Via Pueblo Mall, Stanford, CA 94305, USA; Kavli Institute for Particle Astrophysics & Cosmology, P.O. Box 2450, Stanford University , Stanford, CA 94305, USA
- E. O. Nadler
- ORCiD
- Carnegie Observatories , 813 Santa Barbara Street, Pasadena, CA 91101, USA; Department of Physics & Astronomy, University of Southern California , Los Angeles, CA 90007, USA
- J. Medoff
- ORCiD
- Department of Astronomy and Astrophysics, University of Chicago , Chicago, IL 60637, USA
- A. Drlica-Wagner
- ORCiD
- Department of Astronomy and Astrophysics, University of Chicago , Chicago, IL 60637, USA; Fermi National Accelerator Laboratory , P.O. Box 500, Batavia, IL 60510, USA; Kavli Institute for Cosmological Physics, University of Chicago , Chicago, IL 60637, USA
- W. Cerny
- ORCiD
- Department of Astronomy, Yale University , New Haven, CT 06520, USA
- D. Crnojević
- ORCiD
- Department of Physics and Astronomy, University of Tampa , 401 West Kennedy Boulevard, Tampa, FL 33606, USA
- B. Mutlu-Pakdıl
- ORCiD
- Department of Physics and Astronomy, Dartmouth College , Hanover, NH 03755, USA
- A. K. Vivas
- ORCiD
- Cerro Tololo Inter-American Observatory/NSF’s NOIRLab , Casilla 603, La Serena, Chile
- A. B. Pace
- ORCiD
- McWilliams Center for Cosmology, Carnegie Mellon University , 5000 Forbes Avenue, Pittsburgh, PA 15213, USA
- J. L. Carlin
- ORCiD
- Vera C. Rubin Observatory/AURA , 950 N Cherry Avenue, Tucson, AZ 85719, USA
- M. L. M. Collins
- ORCiD
- Department of Physics, University of Surrey , Guildford GU2 7XH, UK
- P. S. Ferguson
- ORCiD
- Department of Physics, University of Wisconsin-Madison , 1150 University Avenue, Madison, WI 53706, USA ; [email protected]
- D. Martínez-Delgado
- ORCiD
- Instituto de Astrofísica de Andalucía , CSIC, Glorieta de la Astronomía, E-18080 Granada, Spain
- C. E. Martínez-Vázquez
- ORCiD
- Gemini Observatory, NSF's NOIRLab , 670 N. A’ohoku Place, Hilo, HI 96720, USA
- N. E. D. Noel
- ORCiD
- Department of Physics, University of Surrey , Guildford GU2 7XH, UK
- A. H. Riley
- ORCiD
- Institute for Computational Cosmology, Department of Physics, Durham University , South Road, Durham DH1 3LE, UK
- D. J. Sand
- ORCiD
- Steward Observatory, University of Arizona , 933 North Cherry Avenue, Tucson, AZ 85721-0065, USA
- A. Smercina
- ORCiD
- Department of Astronomy, University of Washington , Box 351580, U.W., Seattle, WA 98195-1580, USA
- E. Tollerud
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA
- R. H. Wechsler
- ORCiD
- Department of Physics, Stanford University , 382 Via Pueblo Mall, Stanford, CA 94305, USA; Kavli Institute for Particle Astrophysics & Cosmology, P.O. Box 2450, Stanford University , Stanford, CA 94305, USA; SLAC National Accelerator Laboratory , Menlo Park, CA 94025, USA
- T. M. C. Abbott
- Cerro Tololo Inter-American Observatory/NSF’s NOIRLab , Casilla 603, La Serena, Chile
- M. Aguena
- ORCiD
- Laboratório Interinstitucional de e-Astronomia—LIneA , Rua Gal. José Cristino 77, 20921-400 Rio de Janeiro, RJ, Brazil
- O. Alves
- ORCiD
- Department of Physics, University of Michigan , Ann Arbor, MI 48109, USA
- D. Bacon
- ORCiD
- Institute of Cosmology and Gravitation, University of Portsmouth , Portsmouth PO1 3FX, UK
- C. R. Bom
- ORCiD
- Centro Brasileiro de Pesquisas Físicas , Rua Dr. Xavier Sigaud 150, 22290-180 Rio de Janeiro, RJ, Brazil
- D. Brooks
- ORCiD
- Department of Physics & Astronomy, University College London , Gower Street, London WC1E 6BT, UK
- D. L. Burke
- ORCiD
- Kavli Institute for Particle Astrophysics & Cosmology, P.O. Box 2450, Stanford University , Stanford, CA 94305, USA; SLAC National Accelerator Laboratory , Menlo Park, CA 94025, USA
- J. A. Carballo-Bello
- ORCiD
- Instituto de Alta Investigación, Sede Esmeralda, Universidad de Tarapacá , Av. Luis Emilio Recabarren 2477, Iquique, Chile
- A. Carnero Rosell
- ORCiD
- Laboratório Interinstitucional de e-Astronomia—LIneA , Rua Gal. José Cristino 77, 20921-400 Rio de Janeiro, RJ, Brazil; Instituto de Astrofisica de Canarias , E-38205 La Laguna, Tenerife, Spain; Universidad de La Laguna , Dpto. Astrofísica, E-38206 La Laguna, Tenerife, Spain
- J. Carretero
- ORCiD
- Institut de Física d’Altes Energies (IFAE), The Barcelona Institute of Science and Technology , Campus UAB, E-08193 Bellaterra (Barcelona), Spain
- L. N. da Costa
- ORCiD
- Laboratório Interinstitucional de e-Astronomia—LIneA , Rua Gal. José Cristino 77, 20921-400 Rio de Janeiro, RJ, Brazil
- T. M. Davis
- ORCiD
- School of Mathematics and Physics, University of Queensland , Brisbane, QLD 4072, Australia
- J. De Vicente
- ORCiD
- Centro de Investigaciones Energéticas , Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain
- H. T. Diehl
- ORCiD
- Fermi National Accelerator Laboratory , P.O. Box 500, Batavia, IL 60510, USA
- P. Doel
- Department of Physics & Astronomy, University College London , Gower Street, London WC1E 6BT, UK
- I. Ferrero
- ORCiD
- Institute of Theoretical Astrophysics, University of Oslo P.O. Box 1029 Blindern, NO-0315 Oslo, Norway
- J. Frieman
- ORCiD
- Fermi National Accelerator Laboratory , P.O. Box 500, Batavia, IL 60510, USA; Kavli Institute for Cosmological Physics, University of Chicago , Chicago, IL 60637, USA
- G. Giannini
- ORCiD
- Institut de Física d’Altes Energies (IFAE), The Barcelona Institute of Science and Technology , Campus UAB, E-08193 Bellaterra (Barcelona), Spain
- D. Gruen
- ORCiD
- University Observatory, Faculty of Physics, Ludwig-Maximilians-Universität , Scheinerstr. 1, D-81679 Munich, Germany
- G. Gutierrez
- ORCiD
- Fermi National Accelerator Laboratory , P.O. Box 500, Batavia, IL 60510, USA
- R. A. Gruendl
- ORCiD
- Center for Astrophysical Surveys, National Center for Supercomputing Applications , 1205 West Clark Street, Urbana, IL 61801, USA; Department of Astronomy, University of Illinois at Urbana-Champaign , 1002 W. Green Street, Urbana, IL 61801, USA
- S. R. Hinton
- ORCiD
- School of Mathematics and Physics, University of Queensland , Brisbane, QLD 4072, Australia
- D. L. Hollowood
- ORCiD
- Santa Cruz Institute for Particle Physics , Santa Cruz, CA 95064, USA
- K. Honscheid
- ORCiD
- Center for Cosmology and Astro-Particle Physics, The Ohio State University , Columbus, OH 43210, USA; Department of Physics, The Ohio State University , Columbus, OH 43210, USA
- D. J. James
- ORCiD
- ASTRAVEO LLC , P.O. Box 1668, MA 01931, USA; Applied Materials, Inc. , 35 Dory Road, Gloucester, MA 01930, USA
- K. Kuehn
- ORCiD
- Australian Astronomical Optics, Macquarie University , North Ryde, NSW 2113, Australia; Lowell Observatory , 1400 Mars Hill Road, Flagstaff, AZ 86001, USA
- J. L. Marshall
- ORCiD
- George P. and Cynthia Woods Mitchell Institute for Fundamental Physics and Astronomy, and Department of Physics and Astronomy, Texas A&M University , College Station, TX 77843, USA
- J. Mena-Fernández
- ORCiD
- Centro de Investigaciones Energéticas , Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain
- R. Miquel
- ORCiD
- Institut de Física d’Altes Energies (IFAE), The Barcelona Institute of Science and Technology , Campus UAB, E-08193 Bellaterra (Barcelona), Spain; Institució Catalana de Recerca i Estudis Avançats , E-08010 Barcelona, Spain
- M. E. S. Pereira
- Hamburger Sternwarte, Universität Hamburg , Gojenbergsweg 112, D-21029 Hamburg, Germany
- A. Pieres
- ORCiD
- Laboratório Interinstitucional de e-Astronomia—LIneA , Rua Gal. José Cristino 77, 20921-400 Rio de Janeiro, RJ, Brazil; Observatório Nacional , Rua Gal. José Cristino 77, 20921-400 Rio de Janeiro, RJ, Brazil
- A. A. Plazas Malagón
- ORCiD
- Kavli Institute for Particle Astrophysics & Cosmology, P.O. Box 2450, Stanford University , Stanford, CA 94305, USA; SLAC National Accelerator Laboratory , Menlo Park, CA 94025, USA
- J. D. Sakowska
- ORCiD
- Department of Physics, University of Surrey , Guildford GU2 7XH, UK
- E. Sanchez
- ORCiD
- Centro de Investigaciones Energéticas , Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain
- D. Sanchez Cid
- ORCiD
- Centro de Investigaciones Energéticas , Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain
- B. Santiago
- Laboratório Interinstitucional de e-Astronomia—LIneA , Rua Gal. José Cristino 77, 20921-400 Rio de Janeiro, RJ, Brazil; Instituto de Física , UFRGS, Caixa Postal 15051, 91501-970 Porto Alegre, RS, Brazil
- I. Sevilla-Noarbe
- ORCiD
- Centro de Investigaciones Energéticas , Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain
- M. Smith
- ORCiD
- School of Physics and Astronomy, University of Southampton , Southampton SO17 1BJ, UK
- G. S. Stringfellow
- ORCiD
- Center for Astrophysics and Space Astronomy, University of Colorado , 389 UCB, Boulder, CO 80309-0389, USA
- E. Suchyta
- ORCiD
- Computer Science and Mathematics Division, Oak Ridge National Laboratory , Oak Ridge, TN 37831, USA
- M. E. C. Swanson
- ORCiD
- National Center for Supercomputing Applications , 1205 West Clark Street, Urbana, IL 61801, USA
- G. Tarle
- ORCiD
- Department of Physics, University of Michigan , Ann Arbor, MI 48109, USA
- N. Weaverdyck
- ORCiD
- Department of Physics, University of Michigan , Ann Arbor, MI 48109, USA; Lawrence Berkeley National Laboratory , 1 Cyclotron Road, Berkeley, CA 94720, USA
- P. Wiseman
- School of Physics and Astronomy, University of Southampton , Southampton SO17 1BJ, UK
- DES & DELVE Collaboration
- DOI
- https://doi.org/10.3847/1538-4357/ad07d0
- Journal volume & issue
-
Vol. 961,
no. 1
p. 126
Abstract
We report results from a systematic wide-area search for faint dwarf galaxies at heliocentric distances from 0.3 to 2 Mpc using the full 6 yr of data from the Dark Energy Survey (DES). Unlike previous searches over the DES data, this search specifically targeted a field population of faint galaxies located beyond the Milky Way virial radius. We derive our detection efficiency for faint, resolved dwarf galaxies in the Local Volume with a set of synthetic galaxies and expect our search to be complete to M _V ∼ (−7, −10) mag for galaxies at D = (0.3, 2.0) Mpc. We find no new field dwarfs in the DES footprint, but we report the discovery of one high-significance candidate dwarf galaxy at a distance of ${2.2}_{-0.12}^{+0.05}\,\mathrm{Mpc}$ , a potential satellite of the Local Volume galaxy NGC 55, separated by 47′ (physical separation as small as 30 kpc). We estimate this dwarf galaxy to have an absolute V -band magnitude of $-{8.0}_{-0.3}^{+0.5}\,\mathrm{mag}$ and an azimuthally averaged physical half-light radius of ${2.2}_{-0.4}^{+0.5}\,\mathrm{kpc}$ , making this one of the lowest surface brightness galaxies ever found with $\mu =32.3\,\mathrm{mag}\,{\mathrm{arcsec}}^{-2}$ . This is the largest, most diffuse galaxy known at this luminosity, suggesting possible tidal interactions with its host.
Keywords
