The paper to read today is one from the ATLAS collaboration at the CERN Large Hadron Collider -my competitors, as I work for the other experiment across the ring, CMS. ATLAS has just produced a new article which describes the search for the CP-odd A boson, a particle which arises in Supersymmetry as well as in more generic extensions of the Standard Model called "two-higgs doublet models". What are these ?

"1. Interaction with matter changes the neutrino mixing and effective mass splitting in a way that depends on the mass hierarchy. Consequently, results of oscillations and flavor conversion are different for the two hierarchies.
2. Sensitivity to the mass hierarchy appears whenever the matter effect on the 1-3 mixing and mass splitting becomes substantial. This happens in supernovae in large energy range, and in the matter of the Earth.[...] 
4. Multi-megaton scale under ice (water) atmospheric neutrino detectors with low energy threshold (2-3 GeV) may establish mass hierarchy with (3-10)σ confidence level in few years. [...]

Less than three weeks separate us from the XVI Neutrino Telescopes, a very interesting conference held in Venice every two years. The physics of neutrinos is a very special niche in the realm of particle physics, one not devoid of cunning experimental techniques, brilliant theoretical ideas, and offering possible avenues to discover new physics. Hence I am quite happy to be attending the event, from where I will also be blogging (hopefully with the help of a few students in Padova).(NB this article, as others with neutrinos as a subject for the next month or so, appears also in the conference blog).

A preprint article by the IceCube collaboration captured my attention today in the Cornell Arxiv, and even more interesting was the main result of the analysis it reports, which can be shown as a "temperature plot" on an equilateral triangle. We will get to that, but let me first explain what is the experiment, what are the goals, and what it is that was measured.