TY - JOUR
T1 - Evolution of supernovae-driven superbubbles with conduction and cooling
AU - El-Badry, Kareem
AU - Ostriker, Eve C.
AU - Kim, Chang Goo
AU - Quataert, Eliot
AU - Weisz, Daniel R.
N1 - Funding Information:
We thank the referee for a thoughtful report. We are grateful to Chris Mckee, Yuan Li, and Ken Shen for helpful discussions, and to Drummond Fielding for providing an implementation of radiative cooling in Athena++. KE was supported by an NSF graduate research fellowship. The work of ECO was supported in part by ATP grant NNX17AG26G from NASA and Investigator grant 510940 from the Simons Foundation. CGK was supported in part by grant 528307 from the Simons Foundation. EQ and KE are supported by a Simons Investigator Award from the Simons Foundation and by NSF grant AST-1715070. DRW is supported by a fellowship from the Alfred P. Sloan Foundation and acknowledges support from the Alexander von Humboldt Foundation. This work was initiated as
Publisher Copyright:
© 2019 The Author(s)
PY - 2019/12/1
Y1 - 2019/12/1
N2 - We use spherically symmetric hydrodynamic simulations to study the dynamical evolution and internal structure of superbubbles (SBs) driven by clustered supernovae (SNe), focusing on the effects of thermal conduction and cooling in the interface between the hot bubble interior and cooled shell. Our simulations employ an effective diffusivity to account for turbulent mixing from non-linear instabilities that are not captured in 1D. The conductive heat flux into the shell is balanced by a combination of cooling in the interface and evaporation of shell gas into the bubble interior. This evaporation increases the density, and decreases the temperature, of the SB interior by more than an order of magnitude relative to simulations without conduction. However, most of the energy conducted into the interface is immediately lost to cooling, reducing the evaporative mass flux required to balance conduction. As a result, the evaporation rate is typically a factor of ∼3-30 lower than predicted by the classical similarity solution of (Weaver et al. 1977), which neglects cooling. Blast waves from the first ∼30 SNe remain supersonic in the SB interior because reduced evaporation from the interface lowers the mass they sweep up in the hot interior. Updating the Weaver solution to include cooling, we construct a new analytic model to predict the cooling rate, evaporation rate, and temporal evolution of SBs. The cooling rate, and hence the hot gas mass, momentum, and energy delivered by SBs, is set by the ambient interstellar mass density and the efficiency of non-linear mixing at the bubble-shell interface.
AB - We use spherically symmetric hydrodynamic simulations to study the dynamical evolution and internal structure of superbubbles (SBs) driven by clustered supernovae (SNe), focusing on the effects of thermal conduction and cooling in the interface between the hot bubble interior and cooled shell. Our simulations employ an effective diffusivity to account for turbulent mixing from non-linear instabilities that are not captured in 1D. The conductive heat flux into the shell is balanced by a combination of cooling in the interface and evaporation of shell gas into the bubble interior. This evaporation increases the density, and decreases the temperature, of the SB interior by more than an order of magnitude relative to simulations without conduction. However, most of the energy conducted into the interface is immediately lost to cooling, reducing the evaporative mass flux required to balance conduction. As a result, the evaporation rate is typically a factor of ∼3-30 lower than predicted by the classical similarity solution of (Weaver et al. 1977), which neglects cooling. Blast waves from the first ∼30 SNe remain supersonic in the SB interior because reduced evaporation from the interface lowers the mass they sweep up in the hot interior. Updating the Weaver solution to include cooling, we construct a new analytic model to predict the cooling rate, evaporation rate, and temporal evolution of SBs. The cooling rate, and hence the hot gas mass, momentum, and energy delivered by SBs, is set by the ambient interstellar mass density and the efficiency of non-linear mixing at the bubble-shell interface.
KW - ISM: bubbles
KW - ISM: kinematics and dynamics
KW - ISM: supernova remnants
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U2 - 10.1093/mnras/stz2773
DO - 10.1093/mnras/stz2773
M3 - Article
AN - SCOPUS:85079446881
SN - 0035-8711
VL - 490
SP - 1961
EP - 1990
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 2
ER -