The Diffuse Supernova Neutrino Background

[trinitree88]

You've all heard of the CMB, the cosmological microwave background. Add the DSNB, the diffuse supernova neutrino background. I sorely missed a lecture by John Beacom @ MIT a while back due to professional responsibilities, and came across this ArXiv preprint. While supernovae generate spectacular light shows, revealing lots of information about isotopic compositions of ejecta, light echoes, gamma ray bursts, shock propagation velocities, pulsar transverse velocities and morphologies of remnants....it's the prompt neutrino emissions that characterize the core collapse type 2's. Interestingly, a little gadolinium salts added to Superkamiokande may help open up a study of the diffuse background. Well thought out, with no insurmountable experimental obstacles in sight, a new window on the universe opens up. Man, I'm hoping there's an opportunity for a summer workshop working on this baby. pete

SEE:http://arxiv.org/PS_cache/arxiv/pdf/1004/1004.3311v1.pdf

[baric]

That was a great paper; thanks for the link! There's a lot of overview provided establishing the background for neutrino astronomy, from star formation to stellar mass density to core collapse SN and their frequency. The science behind the use of gandolinium in the SK neutrino detector is discussed.

All in all, an excellent paper worth reading -- even moreso for those (like me) without a formal background in this subject.

[trinitree88]

baric. You're welcome. Glad you enjoyed the paper. Despite most professionals having a great command of their subject matter, and years, often decades of intense research interests, the clarity of their ideas in journals/preprints/talks/blogs doesn't always come across....this one does for me,too. It only takes a glance at Fig. 7 to see that it's doable. pete

[Jerry]

If SK is modified with dissolved gadolinium to reduce detector backgrounds and increase the energy range for analysis, then it should detect
the DSNB at a rate of a few events per year, providing a new probe of supernova neutrino emission and the cosmic core-collapse rate. If the DSNB is not detected, then new physics will be required.

New physics, or a new physical model for supernova events?

There is also another interesting issue: If the true supernova rate is much higher than the detected rate (that is, many more obscured Supernovae than current thinking about dust lanes and such suggests); It could be impossible to seperate 'event' neutrinos from 'background' neutrinos. So 'non-detection' could actually be an indication that the supernova rate is at least equal to expections and well above the observed rate.