===== New CHIMERA simulations page (Series B) =====

We have updated the four CHIMERA simulations for 12-25 solar mass progenitors and provide some details and downloadable content on this page.

==== Simulation details ====

These models (designated **Series B**) are started from the pre-supernova progenitors of [[http://adsabs.harvard.edu/abs/2007PhR...442..269W|Woosley & Heger (2007)]] using 256 angular (theta) zones and 512 radial zones. The initial state extends to 20000-30000 km, which is in the oxygen-rich layers of the progenitor. We use a modern and detailed neutrino-matter interaction set and the [[http://adsabs.harvard.edu/abs/1991NuPhA.535..331L|Lattimer-Swesty]] K=220 MeV nuclear matter equation of state. We use an axisymmetric spherical-polar (r-theta) grid and evolve the models from collapse, through core bounce, to shock revival and explosion.

The four simulations, designated B12-WH07, B15-WH07, B20-WH07, and B25-WH07 are initialized from the 12, 15, 20, and 25 solar mass Woosley-Heger progenitors respectively.

^   Model     ^      Progenitor   ^
| B12-WH07 | 12 solar mass |
| B15-WH07 | 15 solar mass |
| B20-WH07 | 20 solar mass |
| B25-WH07 | 25 solar mass |

==== Paper and plots ====

Paper available at: [[http://arxiv.org/abs/1212.1747|arXiv:1212.1747]]

{{:activities:chimera:b12-wh07_v-radial_entropy.mp4|Animation of radial velocity and entropy}}

==== Relation to previous simulations ====

These models are similar, but not identical to previous simulations (retroactively designated **Series A**) reported in [[http://adsabs.harvard.edu/abs/2009JPhCS.180a2018B|Bruenn et al. (2009)]]. Relative to Series A, these models (Series B) have several improvements and changes to the code and input physics. These include:

Series B models have 512 radial zones (rather than 256) and extend further out into the progenitor.

Series B models use the K=220 MeV version of the Lattimer-Swesty equation of state (rather than K=180 MeV). This reflects better the revised upper limit for neutron stars.

Series B models include neutrino scattering on positrons. (Though this is likely of little impact.)

==== References ====

Paper: Bruenn et al. 2012, submitted to ApJL, [[http://arxiv.org/abs/1212.1747|arXiv:1212.1747]]

Progenitors: Woosley & Heger 2007, Phys. Rep., 442 [[http://adsabs.harvard.edu/abs/2007PhR...442..269W|269]]

Dense nuclear EoS: Lattimer & Swesty 1991, Nuc. Phys. A, 535, [[http://adsabs.harvard.edu/abs/1991NuPhA.535..331L|331]]