Thermohaline instability and rotation-induced mixing II- Yields of 3He for low- and intermediate-mass stars
arXiv:1109.5704 · doi:10.1051/0004-6361/201117739
Abstract
Context. The 3He content of Galactic HII regions is very close to that of the Sun and the solar system, and only slightly higher than the primordial 3He abundance as predicted by the standard Big Bang nucleosynthesis. However, the classical theory of stellar evolution predicts a high production of 3He by low-mass stars, implying a strong increase of 3He with time in the Galaxy. This is the well-known "3He problem". Aims. We study the effects of thermohaline and rotation-induced mixings on the production and destruction of 3He over the lifetime of low- and intermediate-mass stars at various metallicities. Methods. We compute stellar evolutionary models in the mass range 1 to 6M\odot for four metallicities, taking into account thermohaline instability and rotation-induced mixing. For the thermohaline diffusivity we use the prescription based on the linear stability analysis, which reproduces Red Giant Branch (RGB) abundance patterns at all metallicities. Rotation-induced mixing is treated taking into account meridional circulation and shear turbulence. We discuss the effects of these processes on internal and surface abundances of 3He and on the net yields. Results. Over the whole mass and metallicity range investigated, rotation-induced mixing lowers the 3He production, as well as the upper mass limit at which stars destroy 3He. For low-mass stars, thermohaline mixing occuring beyond the RGB bump is the dominant process in strongly reducing the net 3He yield compared to standard computations. Yet these stars remain net 3He producers. Conclusions. Overall, the net 3He yields are strongly reduced compared to the standard framework predictions.
References in corpus (11)
- Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Likelihoods and Parameters from the WMAP data
- A Bitter Pill: The Primordial Lithium Problem Worsens
- Thermohaline mixing: A physical mechanism governing the photospheric composition of low-mass giants
- Deep Mixing of He-3: Reconciling Big Bang and Stellar Nucleosynthesis
- Rotational mixing in low-mass stars II. Self-consistent models of Pop II RGB stars
- First stars IX -Mixing in extremely metal-poor giants. Variation of the 12C/13C, [Na/Mg] and [Al/Mg] ratios
- Diagnoses to unravel secular hydrodynamical processes in rotating main sequence stars
- New Praesepe white dwarfs and the initial mass-final mass relation
- Inhibition of thermohaline mixing by a magnetic field in Ap star descendants: Implications for the Galactic evolution of 3He
- The extra-mixing efficiency in very low metallicity RGB stars
- Thermohaline mixing in low-mass giants
Cited by in corpus (37)
- Stellar yields from metal-rich asymptotic giant branch models
- Thermohaline instability and rotation-induced mixing. III - Grid of stellar models and asymptotic asteroseismic quantities from the pre-main sequence up to the AGB for low- and intermediate-mass stars at various metallicities
- Improved angular momentum evolution model for solar-like stars II. Exploring the mass dependence
- Stellar mass and age determinations - I. Grids of stellar models from Z=0.006 to 0.04 and M=0.5 to 3.5 Msun
- Helium enrichment and Carbon-star Production in Metal-rich Populations
- The role of super-asymptotic giant branch ejecta in the abundance patterns of multiple populations in globular clusters
- The Gaia-ESO survey: impact of extra-mixing on C- and N-abundances of giant stars
- Population synthesis to constrain Galactic and Stellar Physics- I- Determining age and mass of thin-disc red-giant stars
- The Role of Thermohaline Mixing in Intermediate- and Low-Metallicity Globular Clusters
- The Gaia-ESO Survey: CNO abundances in the open clusters Trumpler 20, NGC 4815, and NGC 6705
- Lithium in red giant stars: Constraining non-standard mixing with large surveys in the Gaia era
- Phosphorus-rich stars with unusual abundances are challenging theoretical predictions
- The magnetic strip(s) in the advanced phases of stellar evolution - Theoretical convective turnover timescale and Rossby number for low- and intermediate-mass stars up to the AGB at various metallicities
- C, N, O abundances and carbon isotope ratios in evolved stars of the open clusters Collinder 261 and NGC 6253
- Models of red giants in the CoRoT asteroseismology fields combining asteroseismic and spectroscopic constraints
- Effects of thermohaline instability and rotation-induced mixing on the evolution of light elements in the Galaxy : D, 3He and 4He
- Chemical Mixing Induced by Internal Gravity Waves in Intermediate Mass Stars
- Fingering Convection in Red Giants Revisited
- A phenomenological modification of thermohaline mixing in globular cluster red giants
- The effect of rotation on fingering convection in stellar interiors
- Red clump stars of the Milky Way - laboratories of extra-mixing
- The extent of mixing in stellar interiors: the open clusters Collinder 261 and Melotte 66
- Is Thermohaline Mixing the Full Story? Evidence for Separate Mixing Events near the Red Giant Branch Bump
- The most metal-rich stars in the universe: chemical contributions of low and intermediate mass asymptotic giant branch stars with metallicities between
- Green Bank Telescope Observations of 3He+: HII Regions
- Bridging the Gap between Intermediate and Massive Stars I: Validation of MESA against the State-of-the-Art Monash Stellar Evolution Program for a 2 AGB Star
- Chemical composition of evolved stars in the young open clusters NGC 4609 and NGC 5316
- Lithium in red giants: the roles of the He-core flash and the luminosity bump
- Chemical composition of giant stars in the open cluster IC 4756
- A combined study of thermohaline mixing and envelope overshooting with PARSEC: Calibration to NGC 6397 and M4
- Green Bank Telescope Observations of : Planetary Nebulae
- Do All Low-Mass Stars Undergo Extra Mixing Processes?
- NLTE CNO abundances in a sample of nine field RR lyr type stars
- Toward a Comprehensive Grid of Cepheid Models with MESA II. Impact of Physical and Numerical Assumptions on Elemental Abundances
- Detailed theoretical analysis of core Helium-burning stars: Mixed mode patterns I. Impact of the He-flash discontinuity and of induced semi-convection
- Physical interpretation of the oscillation spectrum on the RGB and AGB
- Primordial helium-3 redux: The helium isotope ratio of the Orion nebula