Evidence found for the Higgs boson direct decay into fermions

Jun 22, 2014
Simulated production of a Higgs event in ATLAS. Image credit: CERN.

For the first time, researchers at CERN have found evidence for the direct decay of the Higgs boson into fermions—another strong indication that the particle discovered in 2012 behaves in the way the standard model of particle physics predicts. Researchers from the University of Zurich made a significant contribution to the study published in Nature Physics.

For the first time, scientists from the CMS experiment on the Large Hadron Collider (LHC) at CERN have succeeded in finding evidence for the direct decay of the Higgs boson into . Previously, the Higgs particle could only be detected through its decay into bosons. "This is a major step forwards," explains Professor Vincenzo Chiochia from the University of Zurich's Physics Institute, whose group was involved in analyzing the data. "We now know that the Higgs particle can decay into both bosons and fermions, which means we can exclude certain theories predicting that the Higgs particle does not couple to fermions." As a group of elementary particles, fermions form the matter while bosons act as force carriers between fermions.

According to the of , the interaction strength between the fermions and the Higgs field must be proportional to their mass. "This prediction was confirmed," says Chiochia; "a strong indication that the particle discovered in 2012 actually behaves like the Higgs particle proposed in the theory."

Combined data analysis

The researchers analyzed the data gathered at the LHC between 2011 and 2012, combining the Higgs decays into bottom quarks and tau leptons, both of which belong to the fermion particle group. The results reveal that an accumulation of these decays comes about at a Higgs particle mass near 125 gigaelectron volts (GeV) and with a significance of 3.8 sigma. This means that the probability of the background alone fluctuating up by this amount or more is about one in 14,000. In particle physics, a discovery is deemed confirmed from a significance of five sigma.

Measuring the Higgs decay modes

Three different processes were studied, whereby the UZH researchers analyzed the Higgs decay into taus. Because the Higgs particle is extremely short-lived, it cannot be detected directly, but rather only via its decay products. The bottom quarks and taus, however, have a long enough lifetime to be measured directly in the CMS experiment's pixel detector.

Explore further: ATLAS sees Higgs boson decay to fermions

More information: Paper: Evidence for the direct decay of the 125 GeV Higgs boson to fermions, Nature Physics DOI: 10.1038/nphys3005

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User comments : 10

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George_Rajna
Jun 22, 2014
This comment has been removed by a moderator.
Whydening Gyre
5 / 5 (3) Jun 22, 2014
George,
You seem to have written a lot of papers on a lot of different things. You maintain a credential list, I assume...?
One other thing - what school is sponsor for academia.edu?
otero
Jun 22, 2014
This comment has been removed by a moderator.
Scryer
5 / 5 (3) Jun 22, 2014
And yet there is always more out there to be discovered.
otero
Jun 22, 2014
This comment has been removed by a moderator.
Uncle Ira
1.3 / 5 (4) Jun 22, 2014
George,
You seem to have written a lot of papers on a lot of different things. You maintain a credential list, I assume...?
One other thing - what school is sponsor for academia.edu?


Hey Whydening-Skippy. How you are Cher? He has only the one paper that he keeps recycling. I got tricked into going to it a couple times of times to see if it was different, it's not different. Same ol mumbo jumbo on all the linkums.
Uncle Ira
1 / 5 (4) Jun 22, 2014
One other thing - what school is sponsor for academia.edu?


P.S. for you Whydening-Skippy. I check on that my own self me. Best I could make out it not a school no. I think is the place where anybody can write their own blog papers and pretend to be the scientist. Zephir-Skippy used to have one of those, but it was a different place he wrote his on. His was a pretty good one too, he had lots of fans come by and read it all the time.
TechnoCreed
4.5 / 5 (8) Jun 22, 2014

@ Zephir
Conclusions
The electric currents causing self maintaining electric potential is the source of the special and general relativistic effects. The Higgs Field is the result of the electromagnetic induction. The graviton is two photons together.
...This comes from George Rajna.

You call that uncontroversial! If you would know any physics you would know that this is garbage from a coo coo. By the way that is the same kind of garbage that you are flooding physorg with. So do not ask yourself why Lubos Motl call you a crackpot and Sabine Hossenfelder do not answer your comments any more.
otero
Jun 22, 2014
This comment has been removed by a moderator.
DeliriousNeuron
3 / 5 (4) Jun 23, 2014
One other thing - what school is sponsor for academia.edu?


P.S. for you Whydening-Skippy. I check on that my own self me. Best I could make out it not a school no. I think is the place where anybody can write their own blog papers and pretend to be the scientist. Zephir-Skippy used to have one of those, but it was a different place he wrote his on. His was a pretty good one too, he had lots of fans come by and read it all the time.


Uncle Ira the Gravity Wizard is at it again!! Looks like you're yhe Skippy around here.
You're posts make 0 sense! Take your meds and go to bed little boy..
mohammadshafiq_khan_1
Jun 23, 2014
This comment has been removed by a moderator.
TimLong2001
5 / 5 (2) Jun 23, 2014
The energies required to form the Higgs boson are much greater than those required for pair-formation, so in a universe formed by "continuous creation" (rather than from a 'big bang') of 1.0216 mev gammarays, the Higgs process would have to come into play at a much later stage of cosmic evolution where the higher energies could exist.
Nashingun
1 / 5 (1) Jun 23, 2014
Evidence you say? Well, how sure are you that what you see is real? Or does it?
How much evidence that it is not Dark Matter that involved itself with it? Science has been adjusting, theorizing and assuming to wrong conclusions over and over and right now we're nowhere close to anything. If Fermions is the end product of Higgs boson... Where is this leading us again?
Mimath224
not rated yet Jun 23, 2014
I need some help here; just what is the Higgs field composed of? Does it vary from point to point (as a temperature field) and therefore open to vector and tensor treatment? The Higgs also get it's mass from the HF so how is the field sustained?
I would appreciate it if someone could direct me to a site/paper that might answer my questions because items that I've veiwed do not.
otero
Jun 28, 2014
This comment has been removed by a moderator.
11791
1 / 5 (1) Jul 02, 2014
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