J/MNRAS/465/2471 Enhanced momentum feedback from clustered SN (Gentry+, 2017)
Enhanced momentum feedback from clustered supernovae.
Gentry E.S., Krumholz M.R., Dekel A., Madau P.
<Mon. Not. R. Astron. Soc. 465, 2471 (2017)>
=2017MNRAS.465.2471G 2017MNRAS.465.2471G (SIMBAD/NED BibCode)
ADC_Keywords: Models ; Supernovae
Keywords: hydrodynamics - ISM: bubbles - ISM: supernova remnants
Abstract:
Young stars typically form in star clusters, so the supernovae (SNe)
they produce are clustered in space and time. This clustering of SNe
may alter the momentum per SN deposited in the interstellar medium
(ISM) by affecting the local ISM density, which in turn affects the
cooling rate. We study the effect of multiple SNe using idealized 1D
hydrodynamic simulations which explore a large parameter space of the
number of SNe, and the background gas density and metallicity. The
results are provided as a table and an analytic fitting formula. We
find that for clusters with up to ∼100 SNe, the asymptotic momentum
scales superlinearly with the number of SNe, resulting in a momentum
per SN which can be an order of magnitude larger than for a single SN,
with a maximum efficiency for clusters with 10-100 SNe. We argue
that additional physical processes not included in our simulations -
self-gravity, breakout from a galactic disc, and galactic shear -
can slightly reduce the momentum enhancement from clustering, but the
average momentum per SN still remains a factor of 4 larger than the
isolated SN value when averaged over a realistic cluster mass function
for a star-forming galaxy. We conclude with a discussion of the
possible role of mixing between hot and cold gas, induced by
multidimensional instabilities or pre-existing density variations, as
a limiting factor in the build-up of momentum by clustered SNe, and
suggest future numerical experiments to explore these effects.
Description:
Key parameters, extracted from every simulation after all SN have
occured and the momentum has reached a maximum.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
results.dat 132 672 SNe simulation results
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Byte-by-byte Description of file: results.dat
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Bytes Format Units Label Explanations
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1- 13 E13.6 kg/m3 Dens Initial gas density
15- 27 E13.6 --- Met Initial gas metallicity
29- 41 E13.6 kg Mcl Cluster mass
43- 46 I4 --- NSNe Number of SNe
48- 60 E13.6 kg.m/s Momentum Peak momentum
62- 74 E13.6 s Time Time of peak momentum
76- 88 E13.6 m Rad SNR radius at time of peak momentum
90-102 E13.6 kg MSNR SNR mass at peak momentum
104-116 E13.6 J EkinSNR SNR kinetic energy at peak momentum
118-130 E13.6 J EintSNR SNR internal energy at peak momentum
132 I1 --- Flag [0/1] Simulation data quality flag (1)
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Note (1): Simulation data quality flag as follows:
1 = successful
0 = unphysical
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Acknowledgements:
Eric Gentry, egentry(at)ucsc.edu
(End) Eric Gentry [[UCSC], Patricia Vannier [CDS] 23-May-2016