Dark matter capture and annihilation in stars: Impact on the red giant branch tip

Abstract

Context: While stars have often been used as laboratories to study dark matter (DM), red giant branch (RGB) stars and all the rich phenomenology they encompass have frequently been overlooked by such endeavors. Aims: We study the capture, evaporation, and annihilation of weakly interacting massive particle (WIMP) DM in low-mass RGB stars ($M=0.8-1.4{\mathrm{M}}_{\odot }$). Methods: We used a modified stellar evolution code to study the effects of DM self-annihilation on the structure and evolution of low-mass RGB stars. Results: We find that the number of DM particles that accumulate inside low-mass RGB stars is not only constant during this phase of evolution, but also mostly independent of the stellar mass and to some extent stellar metallicity. Moreover, we find that the energy injected into the stellar core due to DM annihilation can promote the conditions necessary for helium burning and thus trigger an early end of the RGB phase. The premature end of the RGB, which is most pronounced for DM particles with $m_{\chi }\simeq 100\mathrm{GeV}$, is thus achieved at a lower helium core mass, which results in a lower luminosity at the tip of the red giant branch (TRGB). Although in the current WIMP paradigm, these effects are only relevant if the number of DM particles inside the star is extremely large, we find that for light WIMPs ($m_{\chi }\simeq 4\mathrm{GeV}$), relevant deviations from the standard TRGB luminosity ($\sim 8\%$) can be achieved with conditions that can be realistic in the inner parsec of the Milky Way.

11 pages, 10 figures, 2 tables

References in corpus (22)

• Modules for Experiments in Stellar Astrophysics (MESA)
• Modules for Experiments in Stellar Astrophysics (MESA): Pulsating Variable Stars, Rotation, Convective Boundaries, and Energy Conservation
• Updated Electron-Conduction Opacities: The Impact on Low-Mass Stellar Models
• A new Generation of Standard Solar Models
• WIMP Annihilation and Cooling of Neutron Stars
• Compact Stars as Dark Matter Probes
• Dark matter and the first stars: a new phase of stellar evolution
• Towards Closing the Window on Strongly Interacting Dark Matter: Far-Reaching Constraints from Earth's Heat Flow
• Axion and neutrino bounds improved with new calibrations of the tip of the red-giant branch using geometric distance determinations
• The brightness of the Red Giant Branch tip: Theoretical framework, a set of reference models, and predicted observables
• Dark matter burners
• The RGB tip of galactic globular clusters and the revision of the bound of the axion-electron coupling
• A possible indication of momentum-dependent asymmetric dark matter in the Sun
• The Zero Age Main Sequence of WIMP burners
• Towards the use of asteroseismology to investigate the nature of dark matter
• Signatures of dark matter burning in nuclear star clusters
• A particle dark matter footprint on the first generation of stars
• The Effects of Asymmetric Dark Matter on Stellar Evolution I: Spin-Dependent Scattering
• Asymmetric Dark Matter Imprint on Low-mass Main-sequence Stars in the Milky Way Nuclear Star Cluster
• The impact of composition choices on solar evolution: age, helio- and asteroseismology, and neutrinos
• Towards a more rigorous treatment of uncertainties on the velocity distribution of dark matter particles for capture in stars
• Stellar convective cores as dark matter probes

Cited by in corpus (9)

• Evaporation Barrier for Dark Matter in Celestial Bodies
• Simulation of energy transport by dark matter scattering in stars
• Optimal Celestial Bodies for Dark Matter Detection
• Probing Dark Sectors with Neutron Stars
• Dark Matter (H)eats Young Planets
• Red-Giant Branch Stellar Cores as Macroscopic Dark Matter Detectors
• Influence of dark matter on gravitational stability of isothermal gas clouds
• Impact of Simultaneous Stellar Modeling Uncertainties on the Tip of the Red Giant Branch for Axion-Election Coupling
• Probing Heavy Dark Matter in Red Giants