Dear friends,
I was informed of an article in the journal "Le Monde" commenting new experiments done with the Large Hadron Collider. As I am not a specialist in the matter of the Standard Model, can somebody tell me what is the conclusion of this article? Do the new experiments place under question mark the existence of Higgs' boson? Here is the site of the article:
http://mobile.lemonde.fr/sciences/article/2016/08/29/quelle-strategie-pour-la-physique_4989446_1650684.html
I translate below the first few sentences:
"In the summer of 2012, two international experiments performed with the Large Hadron Collider (LHC), the particle accelerator of the European Organisation for nuclear research (CERN), near Genève, annonced the discovery of Higgs' boson – the last of the particles predicted by the theory of fundamental interactions, baptised « standard model ».
Since then, the machine increased by 60 % the collision energy of the protons. From August, the same teams delivered their last results based on a big number of collision at high energy. The most frequent reaction among the theoreticians in the physics of particles, was consternation.
Contrary to the expectations, the new results confirmed in a spectacular way the predictions of the standard model. This is even more deceiving than the fuzzy preliminary results in the end of 2015, which seemed to indicate the existence of a new particle – sadly famous from now on « resonance of two photons of 750 GeV ».
Such a particle is no part of the Standard Model . . . "
My questions are: 1) what is this resonance; 2) has it any connection with Higgs' boson?
In LHC proton proton collisions are occurring at 13 TeV center of mass. In the scattering process a final state containing two photons is among many processes which are studied. There is a distribution of the number of events vs the invariant mass of the two photons. This graph shows a peak at 750 GeV. This peak also shows an excess of events over the number of those expected assuming purely standard model (that is no new physics). The statistical significance is more than 3σ in both experiemnts (CMS and ATLAS). However still it cannot be called a "discovery" because for that one needs an excess of events which has a statistical significance of 5σ, and which must be supported by two independent experiments.
It is possible that as more and more data is collected by ATLAS and CMS experiments, the excess of number of events over standard model background (which is seen presently) may become statistically less significant or even insignificant.
It has nothing to do with the Higgs, it would have been another new particle, however there is a rumour that more extensive data shows it may have been a false alarm. See the link.
https://www.newscientist.com/article/2100075-physicists-mourn-as-hinted-particle-vanishes-in-leaked-lhc-data/
Dear Sofia D. Wechsler, the resonance frequency for the photon to 750GeV is exactly equal to 750x1000 / 0.51 and equal to 1.47059 * 10 ^ 6 Herz. Regards
Dear Sofia D. Wechsler.
Sorry, I crossed the wires, for any energy of the electron, the frecuancia resonance is always constant and equal to ((2.9979246 * 10 ^ 8) ^ 2 * 9.1095591 * 10 ^ -31) / (6,626 * 10 ^ -34 ) = 1.23563 * 10 ^ 20 Herz. Regards. See: "Teoría QEDa - El átomo y su núcleo", The inverse of expression No. 65 on page No. 54, https://www.researchgate.net/publication/268503521_Teoria_QEDa_-_El_atomo_y_su_nucleo?ev=prf_pub
Book Teoría QEDa - El átomo y su núcleo.
The link has a brief introduction to resonances of the type being discussed.
https://www.physicsforums.com/insights/physics-virtual-particles/
Dear Sofia D. Wechsler.
Today is not my day ! The resonance frequency of the photon (I was thinking of the electron) at 750 GeV is f = E / h equal to 750,000,000 eV / 6.626 * 10 ^ -34 J.s =1.1319*10^42 s^-1. Regards
Daniel, it isn't that kind of resonance, have a look at the link I posted in my last reply.
Dear Sofia D. Wechsler.
Hello, I returned to botch it, I multiplied potatoes with tomatoes! Auful!
The resonance frequency of the photon at 750 GeV is f = E / h equal to (750*10^9*1.602176487*10^-19) J/(6.626*10^-34) J.s=1.81351*10^26 s^-1.
The answer to 2) is the simplest: it doesn't have anything to do with the Higgs boson. Were it a true signal, it would be a new, neutral, spin 0, particle, that could decay into two photons and whose mass would have been 750 times the mass of the proton. It turns out this resonance is just a statistical fluctuation. No such particle exists, when looking at larger datasets. That's the answer to question 1). And it was expected to be, most likely than not, such a fluctuation
- Badges
- Science topic
- Similar topics
- Physical Sciences
- Quantum Physics