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Higgs boson discovery passes peer review

The discovery of the Higgs boson, which “completes the standard model [of particle physics]” according to New Scientist, has passed peer review. Two papers, from the two experiments which each contributed to the discovery, have been published in Volume 716, Issue 1 (17 September 2012) of Physics Letters B, the same journal as Peter Higgs’ original paper which proposed the existence of a “mass-giving boson”. Despite declaring the standard model complete, the New Scientist piece says it is “lacking” and welcomes “the hunt for new physics”. Both papers are “Universally Available” at Science Direct (links below).

Source:  Higgs boson gets peer-review seal of approval (New Scientist).

Papers:
Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC (ATLAS Collaboration, 2012, Physics Letters B, 1-29);
Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC (CMS Collaboration, 2012, Physics Letters B, 30-61).

Related: Have they discovered the Higgs boson? Probably.

Have they discovered the Higgs boson? Probably

I feel that we should acknowledge the announcement made at CERN this morning. As put by Brian Cox on Twitter: “ATLAS and CMS have independently discovered a new particle mass ~ 126 GeV which behaves like [the standard model] Higgs”. This is all based on statistical analysis of experimental data and, since the Higgs cannot be observed directly, there are some outstanding questions that require further research.

Have they discovered the Higgs boson? The answer is: probably. If it’s the Higgs, then it’s a nice example of theoretical physics making demonstrable predictions about nature. If the discovered particle is something else, then there’s a bunch more theoretical work to do to understand this.

Two possible errors in FTL neutrino result

The OPERA project has identified two possible sources of error in the experiment that appeared to observe neutrinos travelling faster than the speed of light. The CERN press release reads:

The OPERA collaboration has informed its funding agencies and host laboratories that it has identified two possible effects that could have an influence on its neutrino timing measurement. These both require further tests with a short pulsed beam. If confirmed, one would increase the size of the measured effect, the other would diminish it. The first possible effect concerns an oscillator used to provide the time stamps for GPS synchronizations. It could have led to an overestimate of the neutrino’s time of flight. The second concerns the optical fibre connector that brings the external GPS signal to the OPERA master clock, which may not have been functioning correctly when the measurements were taken. If this is the case, it could have led to an underestimate of the time of flight of the neutrinos. The potential extent of these two effects is being studied by the OPERA collaboration. New measurements with short pulsed beams are scheduled for May.

Source: OPERA experiment reports anomaly in flight time of neutrinos from CERN to Gran Sasso: UPDATE 23 February 2012.

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