Multiple populations in low mass globular clusters: Palomar 13

Abstract

Since the discovery of chemically peculiar stars in globular clusters in the last century, the study of multiple populations has become increasingly important, given that chemical inhomogeneity is found in almost all globular clusters. Despite various proposed theories attempting to explain this phenomenon, fitting all the observational evidence in globular clusters with one single theory remains notoriously difficult and currently unsuccessful. In order to improve existing models and motivate new ones, we are observing globular clusters at critical conditions, e.g., metal-rich end, metal-poor end, and low mass end. In this paper, we present our first attempt to investigate multiple populations in low mass globular clusters. We obtained low-resolution spectra around 4000 A of 30 members of the globular cluster Palomar 13 using OSIRIS/Multi-object spectrograph mounted at the Gran Telescopio Canarias. The membership of red giant branch stars is confirmed by the latest proper motions from Gaia DR2 and literature velocities. After comparing the measured CN and CH spectral indices with those of the stellar models, we found a clear sign of nitrogen variation among the red giant branch stars. Palomar 13 may be the lowest mass globular cluster showing multiple populations.

ApJ accepted

References in corpus (62)

• Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds
• Gaia Data Release 2. Summary of the contents and survey properties
• A grid of MARCS model atmospheres for late-type stars I. Methods and general properties
• The merger that led to the formation of the Milky Way's inner stellar halo and thick disk
• Co-formation of the Galactic disc and the stellar halo
• Multiple Stellar Populations in Globular Clusters
• The SDSS View of the Palomar-Green Bright Quasar Survey
• Formation and Dynamical Evolution of Multiple Stellar Generations in Globular Clusters
• A catalogue of masses, structural parameters and velocity dispersion profiles of 112 Milky Way globular clusters
• Properties of stellar generations in Globular Clusters and relations with global parameters
• Determining stellar atmospheric parameters and chemical abundances of FGK stars with iSpec
• The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. I. Overview of the Project and Detection of Multiple Stellar Populations
• Evidence for Two Early Accretion Events That Built the Milky Way Stellar Halo
• Origin of the system of globular clusters in the Milky Way
• Thermohaline mixing: A physical mechanism governing the photospheric composition of low-mass giants
• Super-Massive Stars as a Source of Abundance Anomalies of Proton-Capture Elements in Globular Clusters
• Proper motions and dynamics of the Milky Way globular cluster system from Gaia DR2
• Thermohaline instability and rotation-induced mixing. I - Low- and intermediate-mass solar metallicity stars up to the end of the AGB
• Abundance patterns of multiple populations in Globular Clusters: a chemical evolution model based on yields from AGB ejecta
• Origin of the abundance patterns in Galactic globular clusters: constraints on dynamical and chemical properties of globular clusters
• A MegaCam Survey of Outer Halo Satellites. III. Photometric and Structural Parameters
• The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. III. A quintuple stellar population in NGC2808
• Homogeneous Analysis of Globular Clusters from the APOGEE Survey with the BACCHUS Code. II. The Southern Clusters and Overview
• On the Formation of Multiple Stellar Populations in Globular Clusters
• Ruprecht 106: the first single population Globular Cluster?
• Age as a Major Factor in the Onset of Multiple Populations in Stellar Clusters
• Light-element Abundance Variations in the Milky Way Halo
• CN abundance variations on the main sequence of 47 Tuc
• Similarities in Populations of Star Clusters
• Gas expulsion in massive star clusters? Constraints from observations of young and gas-free objects
• Multiple populations in globular clusters and their parent galaxies
• Atypical Mg-poor Milky Way field stars with globular cluster second-generation like chemical patterns
• The Search for Multiple Populations in Magellanic Cloud Clusters III: No evidence for Multiple Populations in the SMC cluster NGC 419
• Palomar 13's Last Stand
• NGC 6535: the lowest mass Milky Way globular cluster with a Na-O anti-correlation? Cluster mass and age in the multiple population context
• Structure and Dynamics of the Globular Cluster Palomar 13
• Chemodynamics of newly identified giants with globular cluster like abundance patterns in the bulge, disk, and halo of the Milky Way
• A search for stellar tidal debris of defunct dwarf galaxies around globular clusters in the inner Galactic halo
• Tidal tails around the outer halo globular clusters Eridanus and Palomar 15
• Two Groups of Red Giants with Distinct Chemical Abundances in the Bulge Globular Cluster NGC 6553 Through the Eyes of APOGEE
• RR Lyrae-based calibration of the Globular Cluster Luminosity Function
• Purveyors of fine halos: Re-assessing globular cluster contributions to the Milky Way halo build-up with SDSS-IV
• The Blue Straggler and Main-sequence Binary Population of the Low-Mass Globular Cluster Palomar 13
• The Metal-poor non-Sagittarius (?) Globular Cluster NGC 5053: Orbit and Mg, Al and Si Abundances
• Wolf-Rayet stars in M81: Detection and Characterization using GTC/OSIRIS spectra and HST/ACS images
• Chemical and kinematic analysis of CN-strong Metal-poor Field Stars in LAMOST DR3
• No evidence for multiple stellar populations in the low-mass Galactic globular cluster E 3
• ESO452-SC11: The lowest mass globular cluster with a potential chemical inhomogeneity
• Explaining the multiple populations in globular clusters by multiple episodes of star formation and enrichment without gas expulsion from massive star feedback
• Ruprecht 106: A riddle, wrapped in a mystery, inside an enigma
• Discovery of Extended Tidal Tails around the Globular Cluster Palomar 13
• On the Chemical and Kinematic Consistency Between N-rich Metal-poor Field Stars and Enriched Populations in Globular Clusters
• HST/WFC3 Observations of Low-Mass Globular Clusters AM 4 and Palomar 13: Physical Properties and Implications for Mass Loss
• Searching for GC-like abundance patterns in young massive clusters II. - Results from the Antennae galaxies
• Chemical abundance analysis of red giant branch stars in the globular cluster E3
• When does the onset of multiple stellar populations in star clusters occur? Detection of enriched stellar populations in NGC 2121
• When does the onset of multiple stellar populations in star clusters occur-III: No evidence of significant chemical variations in main-sequence stars of NGC 419
• A Nitrogen-Enhanced Metal-Poor star discovered in the globular cluster ESO280-SC06
• Pal 13: its moderately extended low density halo and its accretion history
• Identifying Multiple Populations in M71 Using CN
• Searching for Multiple Populations in the Integrated Light of the Young and Extremely Massive Clusters in the Merger Remnant NGC~7252
• When does the onset of multiple stellar populations in star clusters occur-II: No evidence of multiple stellar populations in Lindsay 113

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