The Complexity of the Cetus Stream Unveiled from the Fusion of STREAMFINDER and StarGO

Abstract

We combine the power of two stream-searching tools, STREAMFINDER and StarGO applied to the Gaia EDR3 data, to detect stellar debris belonging to the Cetus stream system that forms a complex, nearly polar structure around the Milky Way. In this work, we find the southern extensions of the northern Cetus stream as the Palca stream and a new southern stream, which overlap on the sky but have different distances. These two stream wraps extend over more than $\sim 100°$ on the sky ($-60°<\delta <+40°$). The current N-body model of the system reproduces both wraps in the trailing arm. We also show that the Cetus system is confidently associated with the Triangulum/Pisces, Willka Yaku, and the recently discovered C-20 streams. The association with the ATLAS-Aliqa Uma stream is much weaker. All of these stellar debris are very metal-poor, comparable to the average metallicity of the southern Cetus stream with [Fe/H] = $-2.17\pm 0.2$. The estimated stellar mass of the Cetus progenitor is at least $10^{5.6}{\mathrm{M}}_{\odot }$, compatible with Ursa Minor or Draco dwarf galaxies. The associated globular cluster with similar stellar mass, NGC 5824 very possibly was accreted in the same group infall. The multi-wrap Cetus stream is a perfect example of a dwarf galaxy that has undergone several periods of stripping, leaving behind debris at multiple locations in the halo. The full characterization of such systems is crucial to unravel the assembly history of the Milky Way and, as importantly, to provide nearby fossils to study ancient low-mass dwarf galaxies.

arXiv commentaccepted to ApJ. The N-body model of the Cetus system is published at https://zenodo.org/record/5771585

References in corpus (111)

• Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds
• The NumPy array: a structure for efficient numerical computation
• The Sloan Digital Sky Survey: Technical Summary
• Gaia Data Release 2. Summary of the contents and survey properties
• The Astropy Project: Building an inclusive, open-science project and status of the v2.0 core package
• Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD
• On the variation of the Initial Mass Function
• The Gaia mission
• PARSEC: stellar tracks and isochrones with the PAdova and TRieste Stellar Evolution Code
• The Initial Mass Function of Stars: Evidence for Uniformity in Variable Systems
• galpy: A Python Library for Galactic Dynamics
• Small-Scale Challenges to the $\Lambda$CDM Paradigm
• The merger that led to the formation of the Milky Way's inner stellar halo and thick disk
• SEGUE: A Spectroscopic Survey of 240,000 stars with g=14-20
• The mass distribution and gravitational potential of the Milky Way
• A 2MASS All-Sky View of the Sagittarius Dwarf Galaxy: I. Morphology of the Sagittarius Core and Tidal Arms
• Tracing Galaxy Formation with Stellar Halos I: Methods
• Co-formation of the Galactic disc and the stellar halo
• Gaia Early Data Release 3: Photometric content and validation
• The Universal Stellar Mass-Stellar Metallicity Relation for Dwarf Galaxies
• Dynamical evolution of star clusters in tidal fields
• Debris streams in the solar neighbourhood as relicts from the formation of the Milky Way
• Eight New Milky Way Companions Discovered in First-Year Dark Energy Survey Data
• The Faintest Dwarf Galaxies
• AGAMA: Action-based galaxy modelling architecture
• Beasts of the Southern Wild: Discovery of nine Ultra Faint satellites in the vicinity of the Magellanic Clouds
• Eight Ultra-faint Galaxy Candidates Discovered in Year Two of the Dark Energy Survey
• The Sagittarius Dwarf Galaxy: a Model for Evolution in a Triaxial Milky Way Halo
• Evidence for Two Early Accretion Events That Built the Milky Way Stellar Halo
• A New Milky Way Dwarf Galaxy in Ursa Major
• Gaia EDR3 view on Galactic globular clusters
• A Faint New Milky Way Satellite in Bootes
• Origin of the system of globular clusters in the Milky Way
• Evidence from the H3 Survey that the Stellar Halo is Entirely Comprised of Substructure
• A New Milky Way Companion: Unusual Globular Cluster or Extreme Dwarf Satellite?
• Formation of omega Centauri from an ancient nucleated dwarf galaxy in the young Galactic disc
• The Luminosity Function of the Milky Way Satellites
• The Quenching of the Ultra-Faint Dwarf Galaxies in the Reionization Era
• The Dark Energy Survey Data Release 2
• Discovery of an Unusual Dwarf Galaxy in the Outskirts of the Milky Way
• A Catalog of Globular Cluster Systems: What Determines the Size of a Galaxy's Globular Cluster Population?
• The Milky Way stellar halo out to 40 kpc : Squashed, broken but smooth
• Tango for three: Sagittarius, LMC, and the Milky Way
• Stellar Streams Discovered in the Dark Energy Survey
• A Prescription for Building the Milky Way's Halo from Disrupted Satellites
• Galactic Halo substructure in the Sloan Digital Sky Survey: the ancient tidal stream from the Sagittarius dwarf galaxy
• The Pristine survey I: Mining the Galaxy for the most metal-poor stars
• Multiple retrograde substructures in the Galactic halo: A shattered view of Galactic history
• Sagittarius II, Draco II and Laevens 3: three new Milky Way satellites discovered in the Pan-STARRS 1 3pi Survey
• The stellar mass-halo mass relation of isolated field dwarfs: a critical test of $\Lambda$CDM at the edge of galaxy formation
• The Sausage Globular Clusters
• Pre-reionization Fossils, Ultra-faint Dwarfs and the Missing Galactic Satellite Problem
• Masses and Scaling Relations for Nuclear Star Clusters, and their Coexistence with Central Black Holes
• Ghostly Tributaries to the Milky Way: Charting the Halo's Stellar Streams with the Gaia DR2 catalogue
• The Auriga Stellar Haloes: Connecting stellar population properties with accretion and merging history
• Contributions to the accreted stellar halo: an atlas of stellar deposition
• The Streams of the Gaping Abyss: A population of entangled stellar streams surrounding the Inner Galaxy
• Charting the Galactic acceleration field I. A search for stellar streams with Gaia DR2 and EDR3 with follow-up from ESPaDOnS and UVES
• Detailed Chemical Abundances in the r-Process-Rich Ultra-Faint Dwarf Galaxy Reticulum 2
• Scaling Relations and the Fundamental Line of the Local Group Dwarf Galaxies
• Hydra II: a faint and compact Milky Way dwarf galaxy found in the Survey of the Magellanic Stellar History
• Gaia early DR3 systemic motions of Local Group dwarf galaxies and orbital properties with a massive Large Magellanic Cloud
• Constraints on the shape of the Milky Way dark matter halo from the Sagittarius stream
• Dynamical Relics of the Ancient Galactic Halo
• Discovery of a New, Polar-Orbiting Debris Stream in the Milky Way Stellar Halo
• Was the Progenitor of the Sagittarius Stream a Disc Galaxy?
• Off the beaten path: Gaia reveals GD-1 stars outside of the main stream
• The Southern Stellar Stream Spectroscopic Survey ($S^5$): Overview, Target Selection, Data Reduction, Validation, and Early Science
• STREAMFINDER I: A New Algorithm for detecting Stellar Streams
• Tracing the formation of the Milky Way through ultra metal-poor stars
• Halo Substructure in the SDSS-Gaia Catalogue : Streams and Clumps
• Origin of the excess of high-energy retrograde stars in the Galactic halo
• $S^5$: The Orbital and Chemical Properties of One Dozen Stellar Streams
• The PAndAS Field of Streams: stellar structures in the Milky Way halo toward Andromeda and Triangulum
• A Cold Milky Way Stellar Stream in the Direction of Triangulum
• A Low-Mass Stellar-Debris Stream Associated with a Globular Cluster Pair in the Halo
• The GALAH Survey: Chemical tagging and chrono-chemodynamics of accreted halo stars with GALAH+ DR3 and $Gaia$ eDR3
• The Pristine survey X: a large population of low-metallicity stars permeates the Galactic disk
• The Southern Stellar Stream Spectroscopic Survey (S5): Chemical Abundances of Seven Stellar Streams
• Elevated r-process enrichment in Gaia Sausage and Sequoia
• Orbital Clustering Identifies the Origins of Galactic Stellar Streams
• Kinematics of Highly R-Process-Enhanced Field Stars: Evidence for an Accretion Origin and Detection of Several Groups from Disrupted Satellites
• Current velocity data on dwarf galaxy NGC1052-DF2 do not constrain it to lack dark matter
• $R$-process enhancements of Gaia-Enceladus in GALAH DR3
• MyGIsFOS: an automated code for parameter determination and detailed abundance analysis in cool stars
• Predicted Extension of the Sagittarius Stream to the Milky Way Virial Radius
• Broken into Pieces: ATLAS and Aliqa Uma as One Single Stream
• Dynamically Tagged Groups of Very Metal-poor Halo Stars from the HK and Hamburg/ESO Surveys
• StarGO: A New Method to Identify the Galactic Origins of Halo Stars
• Evidence of a dwarf galaxy stream populating the inner Milky Way Halo
• Beyond spectroscopy. I. Metallicities, distances, and age estimates for over twenty million stars from SMSS DR2 and Gaia EDR3
• A stellar stream remnant of a globular cluster below the metallicity floor
• The tidal remnant of an unusually metal-poor globular cluster
• The R-Process Alliance: Chemo-Dynamically Tagged Groups of Halo $r$-Process-Enhanced Stars Reveal a Shared Chemical-Evolution History
• Milky Way Tomography with the SkyMapper Southern Survey. II. Photometric Re-calibration of SMSS DR2
• Phlegethon, a nearby $75°$-long retrograde stellar stream
• Formation of Omega Centauri by Tidal Stripping of a Dwarf Galaxy
• Multiple components of the Jhelum stellar stream
• The minimum metallicity of globular clusters and its physical origin -- implications for the galaxy mass-metallicity relation and observations of proto-globular clusters at high redshift
• Kinematics of Tidal Debris from Omega Centauri's Progenitor Galaxy
• The Milky Way's Shell Structure Reveals the Time of a Radial Collision
• Discovery of a Stellar Overdensity in Eridanus-Phoenix in the Dark Energy Survey
• The S2 Stream: the shreds of a primitive dwarf galaxy
• Dynamically Tagged Groups of Metal-Poor Stars from the Best \& Brightest Survey
• Disruption of a Dwarf Galaxy Under Strong Shocking: The Origin of omega Centauri
• Kinematic Discovery of a Stellar Stream located in Pisces
• Revealing the Complicated Story of the Cetus Stream with StarGO
• Is NGC 5824 the Core of the Progenitor of the Cetus Stream?
• R-process-rich stellar streams in the Milky Way
• The chemical composition of NGC5824, a globular cluster without iron spread but with an extreme Mg-Al anticorrelation
• The GALAH Survey: Accreted stars also inhabit the Spite Plateau

Cited by in corpus (19)

• galstreams: A Library of Milky Way Stellar Stream Footprints and Tracks
• GASTRO library I: the simulated chemodynamical properties of several GSE-like stellar halos
• The Pristine survey -- XVI. The metallicity of 26 stellar streams around the Milky Way detected with the STREAMFINDER in Gaia EDR3
• Streams on FIRE: Populations of Detectable Stellar Streams in the Milky Way and FIRE
• The Cetus-Palca stream: A disrupted small dwarf galaxy. A prequel to the science possible with WEAVE with precise spectro-photometric distances
• The e-TidalGCs Project: Modeling the extra-tidal features generated by Galactic globular clusters
• The SDSS-Gaia View of the Color-Magnitude Relation for Blue Horizontal-branch Stars
• Auriga Streams I: disrupting satellites surrounding Milky Way-mass haloes at multiple resolutions
• Hidden deep in the halo: selection of a reduced proper motion halo catalogue and mining retrograde streams in the velocity space
• Existence of Tidal Tails for the Globular Cluster NGC 5824
• A Ghost in Boötes: The Least Luminous Disrupted Dwarf Galaxy
• The Pristine survey: XXVII. The extremely metal-poor stream C-19 stretches over more than 100 degrees
• Globular clusters in \textsc{OrbIT}: complete dynamical characterisation of the globular cluster population of the Milky Way through updated orbital reconstruction
• Segue 2 Recently Collided with the Cetus-Palca Stream: New Opportunities to Constrain Dark Matter in an Ultra-Faint Dwarf
• Milky Way's Metal-Poor Stars display Chemical Transition near the Solar Radius
• Identification of a dwarf galaxy stream in Gaia, and its possible association with the VPOS structure
• HR-GO II: chemical abundances of low-$E$ retrograde dynamically-tagged-groups: Revealing Thamnos as a very metal-poor substructure
• Epicyclic Density Variations in the Indus Stellar Stream
• Investigating the origin of the Milky Way streams. A revised look at their orbital pole distribution in light of precession effects