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Comments from Amol, June 29 2010

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Garching fluxes:

1. Their latest paper (0912. 0260 [astro-ph.SR] 0912.0260, now accepted in PRL) studies two models with 8.8 solar mass till 9 sec. The fluxes we need are in Fig 1 and Fig 2 of this paper, and the tables for these fluxes have been attached. The format of the tables should be self-evident, and we can convert them to whichever form we want for our inputs.

These fluxes, as you can see, predict rather low energies, and also the energies of different neutrino species are rather close together. So the results we get from these simulations may not be very optimistic. However as I mentioned before, these are 8.8 solar mass stars, rather light ones. (no iron, only O-Ne-Mg)

2. Some earlier Garching papers have predictions from stars with 12 and 15 solar masses:

A. astro-ph/0303226: 15 solar masses This is the one whose figures are normally shown in talks. This has the feature of a prominent accretion phase, and the particle flux of nux exceeding that of nue and nuebar at late times (which introduces multiple splits). So this is a model whose numbers may be worth using. Unfortunately the tables for this model are not available (it is too old for them to fish out the tables) However the Figure 3 from this paper can be digitized and used (I think it has enough resolution for our purposes).

B. Phys.Rev.Lett.90:241101,2003 astro-ph/0303171: 11.2 and 15 solar masses This is the "published" Garching version, however it only goes on till about 0.25 sec, so the late-time feature of high nux flux is not seen in this. Here also the tables are not available, but the figure can be digitized.

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Basel fluxes: 8.8, 10.8 and 18 solar masses

These are available in arXiv:0908.1871 [astro-ph.HE] . Again no tables for these, but their fig 2 and fig 14, if digitized, can be used.

These fluxes show almost exact equipartition at all times, so we'll only have the "classic" single split.

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Livermore fluxes:

These are the old simulations that neglect many processes. These give equipartition at all times, and large difference in the nuebar and nux average energies. Here also, only the "classic" single split occurs.

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Now my opinion:

We would like to use fluxes that are realistic and show as many different features as possible. Then we can examine which of these features can be seen at the detectors. Also, we may not want to get lost in different models.

In this sense, I suggest the model from astro-ph/0303226. The features involved are: 1. Prominent accretion phase 2. During accretion phase, only "classic" single split 3. At late times, nux flux exceeds nue/nuebar flux, and "multiple splits" can be observed.

These cover the major features we would like to see. We can then digitize Fig 3 of this paper, and make a table of fluxes. The simulation goes till only 0.75 sec, but one can use a smooth extrapolation if needed.


Cheers, Amol