MAGAZ3NE: Evidence for Galactic Conformity in z ≳ 3 Protoclusters

Ian McConachie; Gillian Wilson; Ben Forrest; Z. Cemile Marsan; Adam Muzzin; M. C. Cooper; Marianna Annunziatella; Danilo Marchesini; Percy Gomez; Wenjun Chang; Stephanie M. Urbano Stawinski; Michael McDonald; Tracy Webb; Allison Noble; Brian C. Lemaux; Ekta A. Shah; Priti Staab; Lori M. Lubin; Roy R. Gal

doi:10.3847/1538-4357/ad8f36

The Astrophysical Journal (Jan 2024)

MAGAZ3NE: Evidence for Galactic Conformity in z ≳ 3 Protoclusters

Ian McConachie,
Gillian Wilson,
Ben Forrest,
Z. Cemile Marsan,
Adam Muzzin,
M. C. Cooper,
Marianna Annunziatella,
Danilo Marchesini,
Percy Gomez,
Wenjun Chang,
Stephanie M. Urbano Stawinski,
Michael McDonald,
Tracy Webb,
Allison Noble,
Brian C. Lemaux,
Ekta A. Shah,
Priti Staab,
Lori M. Lubin,
Roy R. Gal

Affiliations

Ian McConachie: ORCiD; Department of Astronomy, University of Wisconsin–Madison , 475 N. Charter St., Madison, WI 53706 USA, USA ; [email protected]; Department of Physics and Astronomy, University of California, Riverside , 900 University Avenue, Riverside, CA 92521, USA
Gillian Wilson: ORCiD; Department of Physics and Astronomy, University of California, Riverside , 900 University Avenue, Riverside, CA 92521, USA; Department of Physics, University of California, Merced , 5200 North Lake Road, Merced, CA 92543, USA
Ben Forrest: ORCiD; Department of Physics and Astronomy, University of California, Riverside , 900 University Avenue, Riverside, CA 92521, USA; Department of Physics and Astronomy, University of California, Davis , One Shields Avenue, Davis, CA 95616, USA
Z. Cemile Marsan: ORCiD; Department of Physics and Astronomy, York University , 4700, Keele Street, Toronto, ON MJ3 1P3, Canada
Adam Muzzin: ORCiD; Department of Physics and Astronomy, York University , 4700, Keele Street, Toronto, ON MJ3 1P3, Canada
M. C. Cooper: ORCiD; Department of Physics and Astronomy, University of California, Irvine , 4129 Reines Hall, Irvine, CA, USA
Marianna Annunziatella: ORCiD; Centro de Astrobiología (CSIC-INTA) , Ctra de Torrejón a Ajalvir, km 4, E-28850 Torrejón de Ardoz, Madrid, Spain
Danilo Marchesini: ORCiD; Department of Physics & Astronomy, Tufts University , MA 02155, USA
Percy Gomez: ORCiD; W.M. Keck Observatory , 65-1120 Mamalahoa Hwy., Kamuela, HI 96743, USA
Wenjun Chang: ORCiD; Department of Physics and Astronomy, University of California, Riverside , 900 University Avenue, Riverside, CA 92521, USA
Stephanie M. Urbano Stawinski: ORCiD; Department of Physics and Astronomy, University of California, Irvine , 4129 Reines Hall, Irvine, CA, USA
Michael McDonald: Department of Physics and Astronomy, University of California, Riverside , 900 University Avenue, Riverside, CA 92521, USA
Tracy Webb: Department of Physics, McGill Space Institute, McGill University , 3600 rue University, Montréal, QC H3A 2T8, Canada
Allison Noble: School of Earth and Space Exploration, Arizona State University , Tempe, AZ 85287, USA; Beus Center for Cosmic Foundations, Arizona State University , Tempe, AZ 85287, USA
Brian C. Lemaux: ORCiD; Department of Physics and Astronomy, University of California, Davis , One Shields Avenue, Davis, CA 95616, USA; Gemini Observatory , NSF's NOIRLab, 670 N. A’ohoku Place, Hilo, HI 96720, USA
Ekta A. Shah: ORCiD; Department of Physics and Astronomy, University of California, Davis , One Shields Avenue, Davis, CA 95616, USA
Priti Staab: ORCiD; Department of Physics and Astronomy, University of California, Davis , One Shields Avenue, Davis, CA 95616, USA
Lori M. Lubin: ORCiD; Department of Physics and Astronomy, University of California, Davis , One Shields Avenue, Davis, CA 95616, USA
Roy R. Gal: ORCiD; Institute for Astronomy, University of Hawai’i , 2680 Woodlawn Drive, Honolulu, HI 96822, USA

DOI: https://doi.org/10.3847/1538-4357/ad8f36
Journal volume & issue: Vol. 978, no. 1
p. 17

Abstract

Read online

We examine the quiescent fractions of massive galaxies in six z ≳ 3 spectroscopically confirmed protoclusters in the COSMOS field, one of which is newly confirmed and presented here. We report the spectroscopic confirmation of MAGAZ3NE J100143+023021 at $z={3.122}_{-0.004}^{+0.007}$ by the Massive Ancient Galaxies At z > 3 NEar-infrared (MAGAZ3NE) survey. MAGAZ3NE J100143+023021 contains a total of 79 protocluster members (28 spectroscopic and 51 photometric). Three spectroscopically confirmed members are star-forming ultramassive galaxies (UMGs; $\mathrm{log}({M}_{\star }/{M}_{\odot })$ > 11), the most massive of which has $\mathrm{log}({M}_{\star }/{M}_{\odot })$ $\,=\,{11.15}_{-0.06}^{+0.05}$ . Combining Keck/MOSFIRE spectroscopy and the COSMOS2020 photometric catalog, we use a weighted Gaussian kernel density estimator to map the protocluster and measure its total mass ${2.25}_{-0.65}^{+1.55}\times {10}^{14}\,{M}_{\odot }$ in the dense “core” region. For each of the six COSMOS protoclusters, we compare the quiescent fraction to the status of the central UMG as star-forming or quiescent. We observe that galaxies in these protoclusters appear to obey galactic conformity: Elevated quiescent fractions are found in protoclusters with UVJ -quiescent UMGs and low quiescent fractions are found in protoclusters containing UVJ star-frming UMGs. This correlation of star formation/quiescence in UMGs and the massive galaxies nearby in these protoclusters is the first evidence for the existence of galactic conformity at z > 3. Despite disagreements over mechanisms behind conformity at low redshifts, its presence at these early cosmic times would provide strong constraints on the physics proposed to drive galactic conformity.

Published in The Astrophysical Journal

ISSN: 1538-4357 (Online)
Publisher: IOP Publishing
Country of publisher: United Kingdom
LCC subjects: Science: Astronomy: Astrophysics
Website: https://iopscience.iop.org/journal/0004-637X

About the journal

Abstract

Keywords