Long period variables in the globular cluster 47 Tuc: radial velocity variations

Abstract

We present near infrared velocity curves for 12 long period variables (LPVs) in the globular cluster 47 Tuc (NGC 104). New light curves are also presented for these variables. Results are compared with the period-luminosity sequences occupied by the LPVs in the LMC. Sequence C variables (fundamental mode pulsators) have larger velocity amplitudes than sequence B variables (first overtone pulsators). We show that, at similar luminosities, higher mass loss rates are associated with larger pulsation amplitudes. One variable (V18) does not fit the normal period luminosity sequences and it has an unusually large amount of circumstellar dust, suggesting that it has recently undergone a thermal pulse on the AGB. Finally, we report the discovery of three new long period variable stars in the cluster core, all previously found to have a large infrared excess.

arXiv commentaccepted for publication in A&A

References in corpus (14)

• Abundances for Globular Cluster Giants: I. Homogeneous Metallicities for 24 Clusters
• Variable Stars in Galactic Globular Clusters
• Distances and ages of NGC 6397, NGC 6752 and 47 Tuc
• A new IR-Array photometric survey of Galactic Globular Clusters: A detailed study of the RGB sequence as a step towards the global testing of stellar models
• A new analysis of the Red Giant Branch "Tip" distance scale and the value of the Hubble constant
• Red variables in the OGLE-II database. I. Pulsations and period-luminosity relations below the tip of the Red Giant Branch of the LMC
• ISOCAM observations of Galactic Globular Clusters: mass loss along the Red Giant Branch
• Hipparcos period-luminosity relations for Miras and semiregular variables
• Globular Clusters and the Mira Period-Luminosity Relation
• Hubble Space Telescope Observations of the Planetary Nebula K648 in the Globular Cluster M15
• Pulsation at the tip of the first giant branch?
• Evolution of the dust mass loss with luminosity along the giant branch of the globular cluster 47 Tuc
• A Superwind from Early Post-Red Giant Stars?
• A Polarimetric Survey for Dust in 47 Tucanae (NGC 104)

Cited by in corpus (19)

• Horizontal Branch Stars: The Interplay between Observations and Theory, and Insights into the Formation of the Galaxy
• Line formation in AGB atmospheres including velocity effects. Molecular line profile variations of long period variables
• Long period variables in 47 Tuc: direct evidence for lost mass
• Near-Infrared Photometry of Globular Clusters Towards the Galactic Bulge: Observations and Photometric Metallicity Indicators
• A PSF-based Approach to TESS High quality data Of Stellar clusters (PATHOS) -- I. Search for exoplanets and variable stars in the field of 47 Tuc
• Tracing the development of dust around evolved stars: The case of 47 Tuc
• Dust, pulsation, chromospheres and their role in driving mass loss from red giants in Galactic globular clusters
• Dust production and mass loss in the Galactic globular cluster 47 Tucanae
• The first 8-13 micron spectra of globular cluster red giants: circumstellar silicate dust grains in 47 Tucanae (NGC 104)
• High-velocity stars in the cores of globular clusters: The illustrative case of NGC 2808
• Abundance analysis for long-period variables II. RGB and AGB stars in the globular cluster 47\,Tuc
• The Strikingly Metal-Rich Halo of the Sombrero Galaxy
• ALMA reveals sunburn: CO dissociation around AGB stars in the globular cluster 47 Tucanae
• Discovery of long-period variable stars in the very-metal-poor globular cluster M15
• Abundance analysis for long period variables. Velocity effects studied with O-rich dynamic model atmospheres
• The Isaac Newton Telescope monitoring survey of Local Group dwarf galaxies. II. The star formation history of Andromeda I derived from long period variables
• Circumstellar CO J = 3-2 detected around the evolving metal-poor ([Fe/H] ~ -1.15 dex) AGB star RU Vulpeculae
• On the impossible NGC 4372 V1 and V2: an extended AGB to the [Fe/H] = -2.2 cluster
• Automated Identification of the Tip of the Red Giant Branch in Globular Clusters with Gaia Data