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Hi everybody, just wanted to point out that the figure is wrong: the W boson cannot decay to a bottom and a charm. I am sure someone here has the original figure and can fix that? — Preceding unsigned comment added by 5.172.125.72 ( talk) 17:22, 15 September 2015 (UTC)
top lifetime is wrong! — Preceding unsigned comment added by 105.135.86.193 ( talk) 18:21, 25 February 2014 (UTC)
(Ironically, it is not of Top importance.)
Press release from Rolf Heurer: "Chicago, USA and Geneva, Switzerland, 19 March 2014. Scientists working on the world’s leading particle collider experiments have joined forces, combined their data and produced the first joint result from Fermilab’s Tevatron and CERN’s Large Hadron Collider (LHC), past and current holders of the record for most powerful particle collider on Earth. Scientists from the four experiments involved—ATLAS, CDF, CMS and DZero—announced their joint findings on the mass of the top quark today at the Rencontres de Moriond international physics conference in Italy.
Together the four experiments pooled their data analysis power to arrive at a new world’s best value for the mass of the top quark of 173.34 ± 0.76 GeV/c2."
That breaks down as 173.34±0.27(stat)±0.71(syst) GeV ( http://arxiv.org/abs/1403.4427). Graphics are available at http://www.interactions.org/cms/?pid=2100&image_no=OT0172. Pulu ( talk) 20:54, 19 March 2014 (UTC)
I have a rule of thumb about particle physics equations. If I can't make heads or tails out of it, despite being a grad student (albeit an experimentalist), it may be too complex for a general-use encyclopedia. And I have to say I don't understand the the Electroweak symmetry breaking section; in particular, I don't understand the purpose. Is the idea that the proximity of the top mass to a fixed point in the SM RGE is an argument for the MSSM or other supersymmetry model? If so, that should be made explicit, just for starters. One could also ask if we need all those equations, and if the top quark article is really the right place for that argument. -- SCZenz 02:13, 27 January 2006 (UTC)
Sorry for the poor writing. I was just trying clarify what 'evidence for the MSSM' meant -- a bit of an oblique statement. The heaviness of the top disfavours many models of EWSB that involve a composite Higgs or technicolour models -- but that just means it favours an elementary Higgs. Some people claim that the proximity of the top quark's mass to its RG fixed point is evidence for the MSSM over the SM (both of which have elementary HIggs). I (or someone else) should explain that there is a basin of attraction around fixed points of RGs where couplings will flow to at low energies regardless of the initial value of the coupling. Therefore, if you believe that the top Yukawa is just a random number to start with at high energies then it is much more likely for it to be near the fixed point at low energies than some place else. There is certainly a lot that can be said explaining what a fixed point of an RG equation is -- but that probably belongs some place else.
I personally don't like blanket statements about whether a piece of experimental data supports or refutes some unproven theory unless the caveats are stated. To my knowledge this RG argument is the only way that the MSSM is preferred over the SM, and it is not amazingly strong evidence. Nonetheless it is interesting, especially with the (as yet unwritten) backstory that after the top was discovered, every theorist and their brother posted a paper claiming that they had predicted the top mass (through small modifications of this equation).
More concretely, I feel that the questions someone will come to the top quark page with is "what is it?" "why is it special?" "how did we discover it?" "what is the history behind the top?" "why do we care about it?"
Again, my regrets on the poor writing.
-- jay 06:31, 28 January 2006 (UTC)
I'm uncomfortable with the wording. The article states "It was discovered in 1995 by the CDF and D0 experiments at Fermilab". Surely this should read "It was first observed...". Theorists predicted it before then, and as such it was expected to turn up at some high mass.
Apologies if I've missed a previous discussion on use of the word "discovered". I've had a look around and couldn't see anything conclusive.
86.15.240.245 04:26, 28 November 2006 (UTC)
The top quark needs to stay with two other quarks or an antiquark. The strong force overrides the other three forces.-- 67.10.200.101 06:18, 30 June 2007 (UTC)
Someday I want an R baryon to appear, with three top quarks, a spin of 3/2, and a charge of +2. I know that it's not normally possible, but I do wish for a longer lifetime for the top quark.-- Mathexpressions 03:44, 11 July 2007 (UTC)
the t-Quark does have 172.5 ± 2.7 GeV by partical group -> http://pdg.lbl.gov/2007/listings/q007.pdf —Preceding unsigned comment added by 87.123.231.207 ( talk) 04:43, 20 February 2008 (UTC)
And BTW, the 2+2=4 comment in the edit isn't meant to be condescending, it's just that the statement that t quarks have mass comparable to that of a tungsten atom comes down to a simple division. Headbomb ( ταλκ · κοντριβς) 02:51, 12 June 2008 (UTC)
Decay branching ratios were just added to the infobox. Can this information be put in the article itself, along with the source? I don't see it in the PDG, but perhaps I'm just not looking in the right place. - David Schaich Talk/ Cont 16:57, 27 July 2009 (UTC)
See Talk:Quark#Harari's quark model. Headbomb { ταλκ κοντριβς – WP Physics} 00:05, 22 February 2010 (UTC)
H. Harari actually COINED the names of the "top" and "bottom" quarks. Harari was the first to propose a model of six quarks and six leptons, naming the two new quarks “top” and “bottom” (names presently accepted by all), and predicting the existence of six leptons. In August 1975, at the Stanford International Particle Physics conference he presented, for the first time ever, the full synthesis accepted today as “the standard model” of six quarks and six leptons. Its seems that the authors of this page arent from the field of HEP Barak90 ( talk) 10:21, 22 February 2010 (UTC)
2010 PDG values have been posted,
http://pdg.lbl.gov/2010/2010/tables/rpp2010-sum-quarks.pdf
I will wait a few more days before making the changes to mass. If there are no objections I'll apply the changes on Friday August 06, 2010 sometime between 0700 and 2200 UTC.
Abyssoft (
talk) 20:31, 2 August 2010 (UTC)
Added link to full text on arxiv. Someone may wish to remove the reference to the article as published in Prosper's book. It's better to refer to the version everyone can freely access electronically. -- Biggus Dictus ( talk) 18:03, 13 October 2011 (UTC)
There a several passages in the article that are speculative over the existence or mass of the Higgs boson, particularly 'using the bare quark and extensions of the standard model to predict the Higgs Boson's mass'. The Higgs boson was first confirmed in 2013 with a mass between 125 and 127 GeV/(c^2). Should the article be rewritten to reflect this? — Preceding unsigned comment added by 2001:630:E4:4220:F0A7:549B:32AC:5019 ( talk) 01:48, 5 February 2017 (UTC)
An editor has asked for a discussion to address the redirect Heaviest subatomic particle. Please participate in the redirect discussion if you wish to do so. Steel1943 ( talk) 20:39, 20 September 2019 (UTC)
Hi all, these two paragraphs under the section about Higgs coupling have some redundancy:
"The Standard Model generates fermion masses through their couplings to the Higgs boson. This Higgs boson acts as a field filling space. Fermions interact with this field in proportion to their individual coupling constants y i {\displaystyle y_{i}} y_{i}, which generates mass. A low-mass particle, such as the electron has a minuscule coupling y electron = 2 × 10 − 6 {\displaystyle y_{\text{electron}}=2\times 10^{-6}} {\displaystyle y_{\text{electron}}=2\times 10^{-6}}, while the top quark has the largest coupling to the Higgs, y t ≃ 1 {\displaystyle y_{\text{t}}\simeq 1} {\displaystyle y_{\text{t}}\simeq 1}. These couplings are usually called the Higgs–Yukawa couplings, and they vary slowly as the energy scale at which they are measured is varied, due to a quantum effect called the renormalization group.
In the Standard Model, all of the quark and lepton Higgs–Yukawa couplings are small compared to the top-quark Yukawa coupling. This hierarchy in the fermion masses remains a profound and open problem in theoretical physics. Higgs–Yukawa couplings are not fixed constants of nature, as their values vary slowly as the energy scale (distance scale) at which they are measured. This dynamics of Higgs–Yukawa couplings, called "running coupling constants", is due to a quantum effect called the renormalization group."
150.135.165.22 ( talk) 03:38, 21 November 2020 (UTC)
I'm not familiar in this subject, but was wondering if this was in wikipedia.
[1] - Observation of the associated production of a top quark and a Z boson in pp collisions at s√=13 TeV with the ATLAS detector. Thanks,
Marasama (
talk) 22:23, 22 November 2020 (UTC)
This is wrong. There is no coupling to the Higgs Boson. The coupling is to the Higgs Field. 134.171.73.35 ( talk) 10:55, 31 October 2023 (UTC)
A fact from this article was featured on Wikipedia's Main Page in the On this day section on March 2, 2020. |
This
level-5 vital article is rated B-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | |||||||||||
|
Hi everybody, just wanted to point out that the figure is wrong: the W boson cannot decay to a bottom and a charm. I am sure someone here has the original figure and can fix that? — Preceding unsigned comment added by 5.172.125.72 ( talk) 17:22, 15 September 2015 (UTC)
top lifetime is wrong! — Preceding unsigned comment added by 105.135.86.193 ( talk) 18:21, 25 February 2014 (UTC)
(Ironically, it is not of Top importance.)
Press release from Rolf Heurer: "Chicago, USA and Geneva, Switzerland, 19 March 2014. Scientists working on the world’s leading particle collider experiments have joined forces, combined their data and produced the first joint result from Fermilab’s Tevatron and CERN’s Large Hadron Collider (LHC), past and current holders of the record for most powerful particle collider on Earth. Scientists from the four experiments involved—ATLAS, CDF, CMS and DZero—announced their joint findings on the mass of the top quark today at the Rencontres de Moriond international physics conference in Italy.
Together the four experiments pooled their data analysis power to arrive at a new world’s best value for the mass of the top quark of 173.34 ± 0.76 GeV/c2."
That breaks down as 173.34±0.27(stat)±0.71(syst) GeV ( http://arxiv.org/abs/1403.4427). Graphics are available at http://www.interactions.org/cms/?pid=2100&image_no=OT0172. Pulu ( talk) 20:54, 19 March 2014 (UTC)
I have a rule of thumb about particle physics equations. If I can't make heads or tails out of it, despite being a grad student (albeit an experimentalist), it may be too complex for a general-use encyclopedia. And I have to say I don't understand the the Electroweak symmetry breaking section; in particular, I don't understand the purpose. Is the idea that the proximity of the top mass to a fixed point in the SM RGE is an argument for the MSSM or other supersymmetry model? If so, that should be made explicit, just for starters. One could also ask if we need all those equations, and if the top quark article is really the right place for that argument. -- SCZenz 02:13, 27 January 2006 (UTC)
Sorry for the poor writing. I was just trying clarify what 'evidence for the MSSM' meant -- a bit of an oblique statement. The heaviness of the top disfavours many models of EWSB that involve a composite Higgs or technicolour models -- but that just means it favours an elementary Higgs. Some people claim that the proximity of the top quark's mass to its RG fixed point is evidence for the MSSM over the SM (both of which have elementary HIggs). I (or someone else) should explain that there is a basin of attraction around fixed points of RGs where couplings will flow to at low energies regardless of the initial value of the coupling. Therefore, if you believe that the top Yukawa is just a random number to start with at high energies then it is much more likely for it to be near the fixed point at low energies than some place else. There is certainly a lot that can be said explaining what a fixed point of an RG equation is -- but that probably belongs some place else.
I personally don't like blanket statements about whether a piece of experimental data supports or refutes some unproven theory unless the caveats are stated. To my knowledge this RG argument is the only way that the MSSM is preferred over the SM, and it is not amazingly strong evidence. Nonetheless it is interesting, especially with the (as yet unwritten) backstory that after the top was discovered, every theorist and their brother posted a paper claiming that they had predicted the top mass (through small modifications of this equation).
More concretely, I feel that the questions someone will come to the top quark page with is "what is it?" "why is it special?" "how did we discover it?" "what is the history behind the top?" "why do we care about it?"
Again, my regrets on the poor writing.
-- jay 06:31, 28 January 2006 (UTC)
I'm uncomfortable with the wording. The article states "It was discovered in 1995 by the CDF and D0 experiments at Fermilab". Surely this should read "It was first observed...". Theorists predicted it before then, and as such it was expected to turn up at some high mass.
Apologies if I've missed a previous discussion on use of the word "discovered". I've had a look around and couldn't see anything conclusive.
86.15.240.245 04:26, 28 November 2006 (UTC)
The top quark needs to stay with two other quarks or an antiquark. The strong force overrides the other three forces.-- 67.10.200.101 06:18, 30 June 2007 (UTC)
Someday I want an R baryon to appear, with three top quarks, a spin of 3/2, and a charge of +2. I know that it's not normally possible, but I do wish for a longer lifetime for the top quark.-- Mathexpressions 03:44, 11 July 2007 (UTC)
the t-Quark does have 172.5 ± 2.7 GeV by partical group -> http://pdg.lbl.gov/2007/listings/q007.pdf —Preceding unsigned comment added by 87.123.231.207 ( talk) 04:43, 20 February 2008 (UTC)
And BTW, the 2+2=4 comment in the edit isn't meant to be condescending, it's just that the statement that t quarks have mass comparable to that of a tungsten atom comes down to a simple division. Headbomb ( ταλκ · κοντριβς) 02:51, 12 June 2008 (UTC)
Decay branching ratios were just added to the infobox. Can this information be put in the article itself, along with the source? I don't see it in the PDG, but perhaps I'm just not looking in the right place. - David Schaich Talk/ Cont 16:57, 27 July 2009 (UTC)
See Talk:Quark#Harari's quark model. Headbomb { ταλκ κοντριβς – WP Physics} 00:05, 22 February 2010 (UTC)
H. Harari actually COINED the names of the "top" and "bottom" quarks. Harari was the first to propose a model of six quarks and six leptons, naming the two new quarks “top” and “bottom” (names presently accepted by all), and predicting the existence of six leptons. In August 1975, at the Stanford International Particle Physics conference he presented, for the first time ever, the full synthesis accepted today as “the standard model” of six quarks and six leptons. Its seems that the authors of this page arent from the field of HEP Barak90 ( talk) 10:21, 22 February 2010 (UTC)
2010 PDG values have been posted,
http://pdg.lbl.gov/2010/2010/tables/rpp2010-sum-quarks.pdf
I will wait a few more days before making the changes to mass. If there are no objections I'll apply the changes on Friday August 06, 2010 sometime between 0700 and 2200 UTC.
Abyssoft (
talk) 20:31, 2 August 2010 (UTC)
Added link to full text on arxiv. Someone may wish to remove the reference to the article as published in Prosper's book. It's better to refer to the version everyone can freely access electronically. -- Biggus Dictus ( talk) 18:03, 13 October 2011 (UTC)
There a several passages in the article that are speculative over the existence or mass of the Higgs boson, particularly 'using the bare quark and extensions of the standard model to predict the Higgs Boson's mass'. The Higgs boson was first confirmed in 2013 with a mass between 125 and 127 GeV/(c^2). Should the article be rewritten to reflect this? — Preceding unsigned comment added by 2001:630:E4:4220:F0A7:549B:32AC:5019 ( talk) 01:48, 5 February 2017 (UTC)
An editor has asked for a discussion to address the redirect Heaviest subatomic particle. Please participate in the redirect discussion if you wish to do so. Steel1943 ( talk) 20:39, 20 September 2019 (UTC)
Hi all, these two paragraphs under the section about Higgs coupling have some redundancy:
"The Standard Model generates fermion masses through their couplings to the Higgs boson. This Higgs boson acts as a field filling space. Fermions interact with this field in proportion to their individual coupling constants y i {\displaystyle y_{i}} y_{i}, which generates mass. A low-mass particle, such as the electron has a minuscule coupling y electron = 2 × 10 − 6 {\displaystyle y_{\text{electron}}=2\times 10^{-6}} {\displaystyle y_{\text{electron}}=2\times 10^{-6}}, while the top quark has the largest coupling to the Higgs, y t ≃ 1 {\displaystyle y_{\text{t}}\simeq 1} {\displaystyle y_{\text{t}}\simeq 1}. These couplings are usually called the Higgs–Yukawa couplings, and they vary slowly as the energy scale at which they are measured is varied, due to a quantum effect called the renormalization group.
In the Standard Model, all of the quark and lepton Higgs–Yukawa couplings are small compared to the top-quark Yukawa coupling. This hierarchy in the fermion masses remains a profound and open problem in theoretical physics. Higgs–Yukawa couplings are not fixed constants of nature, as their values vary slowly as the energy scale (distance scale) at which they are measured. This dynamics of Higgs–Yukawa couplings, called "running coupling constants", is due to a quantum effect called the renormalization group."
150.135.165.22 ( talk) 03:38, 21 November 2020 (UTC)
I'm not familiar in this subject, but was wondering if this was in wikipedia.
[1] - Observation of the associated production of a top quark and a Z boson in pp collisions at s√=13 TeV with the ATLAS detector. Thanks,
Marasama (
talk) 22:23, 22 November 2020 (UTC)
This is wrong. There is no coupling to the Higgs Boson. The coupling is to the Higgs Field. 134.171.73.35 ( talk) 10:55, 31 October 2023 (UTC)