I have reported about the studies of resonances in the decays of the B+ meson by CDF, CMS, and LHCb a few times in the recent past. The situation, in a nutshell, was the following until yesterday: CDF found a new particle, the Y(4140), as a resonant (J/ψ φ) intermediate state produced when B+ mesons decay into a J/ψ, a φ, and a positive kaon; CDF also saw some evidence for a further excitation of the same two-body system; CMS confirmed the CDF claims, finding observation-level significance for both states; and LHCb did not confirm either of the two.
Furthermore Belle, a B-factory experiment studying electron-positron collisions, also found no evidence for the Y(4140) state.
The ATLAS Collaboration published last week
the results of a search for dark matter particles produced in association with a W or Z boson by the 8-TeV proton-proton collisions collected during the 2012 run of the Large Hadron Collider. The search uses techniques similar to ones I have described in recent articles here discussing results of the CMS experiments on different new physics signatures, and I thought it would be interesting to review it here.
Three weeks ago I gave a plenary talk at the 2nd International Conference on New Frontiers in Physics
, which was held in Kolymbari, in the greek island of Crete. The talk focused on some of the most interesting new results by the CMS Collaboration, but being just 30' long it only contained a summary of these. The purpose of the talk was primarily that of advertising the many talks on specific physics topics -Top, Higgs, Exotica, QCD- which were given by some of my colleagues in the parallel sessions; however I was able to show and discuss some nice new measurements myself.
Every once in a while I feel compelled to write in clear what should be self-evident to anybody with a working brain; to give a sort of "advice to surfers". I don't expect that such an advice be taken seriously - nobody wants to be told what to read and what to avoid - but at least it is posted, can be referred to, and it provides a sort of "disclaimer of liability".
Writing a serious blog, i.e. one that informs with continuity one audience and provides a true service, is already quite a demanding task; having to cope with the aftermath of articles that may inflame some readers, or with out-of-topic comments, or with the anger of whomever happens to feel outraged or offended, is sometimes too much. Hence the wish to keep that extra work at a minimum, manageable level.