%0 Generic %1 rindlerdaller2020stability %A Rindler-Daller, Tanja %A Freese, Katherine %A Townsend, Richard H. D. %A Visinelli, Luca %D 2020 %K journal_club %T Stability and pulsation of the first dark stars %U http://arxiv.org/abs/2011.00231 %X The first bright objects to form in the Universe might not have been ördinary" fusion-powered stars, but "Dark Stars" (DSs) powered by the annihilation of dark matter (DM) in the form of Weakly Interacting Massive Particles (WIMPs). If discovered, DSs can provide a unique laboratory to test DM models. DSs are born with a mass of order $M_ødot$ and may grow to a few million solar masses; in this work we investigate the properties of early DSs with masses up to $\! 1000 \, M_ødot$, fueled by WIMPS weighing $100$ GeV. We improve the previous implementation of the DM energy source into the stellar evolution code MESA. We show that the growth of DSs is not limited by astrophysical effects: DSs up to $\! 1000 \, M_ødot$ exhibit no dynamical instabilities; DSs are not subject to mass-loss driven by super-Eddington winds. We test the assumption of previous work that the injected energy per WIMP annihilation is constant throughout the star; relaxing this assumption does not change the properties of the DSs. Furthermore, we study DS pulsations, for the first time investigating non-adiabatic pulsation modes, using the linear pulsation code GYRE. We find that acoustic modes in DSs of masses smaller than $\! 200 \, M_ødot$ are excited by the $\kappa-\gamma$ and $\gamma$ mechanism in layers where hydrogen or helium is (partially) ionized. Moreover, we show that the mass-loss rates potentially induced by pulsations are negligible compared to the accretion rates.

@misc{rindlerdaller2020stability, abstract = {The first bright objects to form in the Universe might not have been "ordinary" fusion-powered stars, but "Dark Stars" (DSs) powered by the annihilation of dark matter (DM) in the form of Weakly Interacting Massive Particles (WIMPs). If discovered, DSs can provide a unique laboratory to test DM models. DSs are born with a mass of order $M_\odot$ and may grow to a few million solar masses; in this work we investigate the properties of early DSs with masses up to $\sim \! 1000 \, M_\odot$, fueled by WIMPS weighing $100$ GeV. We improve the previous implementation of the DM energy source into the stellar evolution code MESA. We show that the growth of DSs is not limited by astrophysical effects: DSs up to $\sim \! 1000 \, M_\odot$ exhibit no dynamical instabilities; DSs are not subject to mass-loss driven by super-Eddington winds. We test the assumption of previous work that the injected energy per WIMP annihilation is constant throughout the star; relaxing this assumption does not change the properties of the DSs. Furthermore, we study DS pulsations, for the first time investigating non-adiabatic pulsation modes, using the linear pulsation code GYRE. We find that acoustic modes in DSs of masses smaller than $\sim \! 200 \, M_\odot$ are excited by the $\kappa-\gamma$ and $\gamma$ mechanism in layers where hydrogen or helium is (partially) ionized. Moreover, we show that the mass-loss rates potentially induced by pulsations are negligible compared to the accretion rates.}, added-at = {2020-11-03T08:57:51.000+0100}, author = {Rindler-Daller, Tanja and Freese, Katherine and Townsend, Richard H. D. and Visinelli, Luca}, biburl = {https://www.bibsonomy.org/bibtex/29983e0739a74cc2913aef587c5f6eebc/bhvzchhn}, description = {[2011.00231] Stability and pulsation of the first dark stars}, interhash = {d88f64a5916c7ea9a397da19beea555a}, intrahash = {9983e0739a74cc2913aef587c5f6eebc}, keywords = {journal_club}, note = {cite arxiv:2011.00231Comment: submitted to MNRAS; 14 pages, 6 Figures}, timestamp = {2020-11-03T08:57:51.000+0100}, title = {Stability and pulsation of the first dark stars}, url = {http://arxiv.org/abs/2011.00231}, year = 2020 }