The CDF and DZERO experiments recently produced a combination of their precision measurements of the W boson mass
, and proceeded to include the LEP II results to obtain a "world average" of that very important parameter of the Standard Model.
The measurement is described in detail in a paper which explains the combination procedure (not trivial, since there are a number of systematic uncertainties that are partly correlated between the experiments). The Tevatron inputs are as follows:
CDF Run I (107/pb, 1.8 TeV): M_W = 80432+-79 MeV
CDF Run II (2.2/fb, 1.96 TeV): M_W = 80387+-19 MeV
DZERO Run I (95/pb, 1.8 TeV): M_W = 80478+-83 MeV
The Dolomites are a mountain range in north-eastern Italy. They take their name from the mineral called dolomite, a carbonate rock which gives these mountains a characteristic pale pink colour, especially notable at sunset. Their composition is also responsible, at least in part, for their shape.
Most of the peaks are in the 2500-3000 meters of height above sea level, the tallest being mount "Marmolada", at 3342 meters. Despite being less tall than other mountain ridges in the Italian Alps, the Dolomites are reknowned for their breathtaking landscapes, as well as for the ski slopes they offer, especially -but not only- in the region around Cortina d'Ampezzo.
Today I received news of an interesting measurement of angular distributions of the decay products in the rare decay of the B meson to a K* and a muon pair - one of the specialties of the LHCb collaboration, which has more horse-power in some of these low-energy measurements than ATLAS and CMS.
I reported two days ago on the new measurements by the CMS Collaboration of the decay of B hadrons into muon pairs, revealed at the opening of the EPS 2013 conference in Stockholm and in a preprint. Funnily, I wrote the piece oblivious of the LHCb result, which is basically equivalent (in importance, precision, and sensitivity) to the CMS one; when I found out that LHCb had also a comparable result, I made up for that by pointing out the LHCb result in a "UPDATE" at the end of the post - I did not want to rewrite half of the piece!
Today I am quite happy to report of a new groundbreaking result from the CMS collaboration at the CERN LHC - the experiment to which I devote 100% of my research time. We published overnight a report on the Cornell arxiv
, and will present this week at the EPS conference in Stockholm
, of the observation of B_s meson decays to muon pairs, an exceedingly rare process which is of extreme importance for the searches of new physics beyond the standard model. And in so doing, CMS now leads this race, with better results than LHCb and ATLAS. (UPDATE
: but see below, at the bottom of the article).
The querelle on the device patented by Andrea Rossi, the E-CAT, which allegedly produces heat from nuclear fusion processes inside a small cylindrical reactor fueled with Hydrogen and Nickel powder, continues to draw the attention of the gullible as well as that of the knowledgeable. It is just entertaining to both!