The "Cosmic Seagull": A Highly Magnified Disk-like Galaxy at z ≃ 2.8 behind the Bullet Cluster
Artikel i vetenskaplig tidskrift, 2018
We present Atacama Large Millimeter/submillimeter Array measurements of the "Cosmic Seagull," a strongly magnified galaxy at z = 2.7779 behind the Bullet Cluster. We report CO(3-2) and continuum 344 μm (rest-frame) data at one of the highest differential magnifications ever recorded at submillimeter wavelengths (μ up to ∼50), facilitating a characterization of the kinematics of a rotational curve in great detail (at ∼620 pc resolution in the source plane). We find no evidence for a decreasing rotation curve, from which we derive a dynamical mass of (6.3 ± 0.7) × 1010Mowithin r = 2.6 ± 0.1 kpc. The discovery of a third, unpredicted, image provides key information for a future improvement of the lensing modeling of the Bullet Cluster and allows a measure of the stellar mass, , unaffected by strong differential magnification. The baryonic mass is expected to be dominated by the molecular gas content (fgas≤ 80 ± 20%) based on an mass estimated from the difference between dynamical and stellar masses. The star formation rate (SFR) is estimated via the spectral energy distribution (SFR = 190 ± 10 Moyr-1), implying a molecular gas depletion time of 0.25 ± 0.08 Gyr.
galaxies: ISM
galaxies: clusters: individual (1ES0657-558)
galaxies: evolution
gravitational lensing: strong
submillimeter: galaxies
Författare
V. Motta
Universidad de Valparaíso
E. Ibar
Universidad de Valparaíso
T. Verdugo
Universidad Nacional Autónoma de México
J. Molina
Universidad de Chile
T. M. Hughes
Chinese Academy of Sciences
University of Science and Technology of China
Universidad de Valparaíso
M. Birkinshaw
University of Bristol
O. López-Cruz
Instituto Nacional de Astrofísica, Óptica y Electrońica
John H Black
Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik
D. Gunawan
Universidad de Valparaíso
Cathy Horellou
Chalmers, Rymd-, geo- och miljövetenskap, Astronomi och plasmafysik
J. Magana
Universidad de Valparaíso
Astrophysical Journal Letters
2041-8205 (ISSN) 2041-8213 (eISSN)
Vol. 863 2 L16Ämneskategorier
Subatomär fysik
Astronomi, astrofysik och kosmologi
Atom- och molekylfysik och optik
Fundament
Grundläggande vetenskaper
DOI
10.3847/2041-8213/aad6de