Core-collapse Supernovae discussion notes ----------------------------------------- 1) Reisswig & Sutton: mano-a-mano Shock stalls need another mechanism to revive shock, otherwise collapse to black hole (collapsar) accreting matter onto proto NS is remnant iron core can collapsar be simulated? Not entirely because the hyper accretion phase lasts for hundreds of seconds and requires a lot of computing power. Need magnetic fields, better EOS (previously used polytrope) and neutrinos. Getting collapsar BH waveforms required about 3 months and, apart from missing physics, need smart NR approach to deal with hyper accretion move from 2D to 3D, the SASI amplitude is not as large because there are more degrees of freedom combination of neutrino heating, SASI (and others?) revive the shock SASI is a robust feature in 2D but difficult to simulate neutrino transport in 3D different groups use/focus on different physics in their simulations perhaps the SNe simulators can agree on the physics they want in their models and compare the results of their simulations (2D or even 3D?) quantifying importance of GR: modified Newtonian is sufficient for slow rotating, CFC approximation is ok for fast rotation. Multiple bounce spikes are ruled out by GR Dimmelmeier waveform power spectrum is flat across the band which is interesting (some process is saturating?) what governs the size of time-freq pixels? They are chosen by the analysts but, in general, the code looks at the data on different time-frequency resolutions are these waveforms a good sample? The main features are robust if we assume that there is always some rotation. Without rotation, convection takes over and it looks like a broadband white noise burst all waveforms are linearly polarised and the broadband white noise bursts should be randomly polarised polarisation content can inform the search so it is important to get correct information 2) Reisswig: Neutrinos and core-collapse supernovae most stars are not rotating rapidly ("rapid" as defined in the simulations) 3D...octant (only simulate 1 octant of 3D space) why the different SNR? More rotation means core bounce is more oblate which triggers a stronger f-mode signal why does IceCube have poor timing resolution? how long over which most(~90%) of neutrinos ejected? proto NS cools in seconds, so most neutrinos are radiated within that time will neutrinos affect formation of black hole? The neutrino signal will shut off when BH is formed since neutrinos are radiated from proto NS 3) Logue: Inferring Core-Collapse Supernova Physics with GWs shouldn't these waveforms be the same or robust features be similar? no rotation in neutrino waveforms, magnetorotational have rotation...etc... what features are robust? are the time delays between features robust? For rapid rotation, the PNS modes will be excited. For SASI, the broadband white noise burst will definitely be expected. 4) Cera-Duran: Simulating BHs from collapsars Kerr metric in conformal flatness is used to get a rough idea of BH formation Difference in delay to BH formation time due to accretion heating which is included in GRID while CoCoNUT uses neutrino leakage how do you treat the outer boundary? The density is smaller and it does not affect things very much 5) Discussion If there was one thing you can get from DA, what would you like? Pablo L: better quantify what they mean about robust features so that they can better focus their simulations Christian R: if you can pull the features apart from SNe waveforms and get the physics out, that would be great Pablo CD: create some parameterised catalogue which tries to fit the main features; bounce, linearly polarised and scale with NS plus convection, circularly polarised and scale with..., at high rotation, we get bar mode instability, observations will inform simulators (description of features, etc) Can get orientation info from neutrinos, eg SK? Can the ratio of neutrino flavours be predicted in the code? Not right now