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antoniseb
2011-Dec-03, 02:21 PM
Rumor is that on Dec 13 they will announce an almost three sigma likely candidate for the Higgs particle at about 125 GeV. Lots of buzz, but you'll probably have to wait for Dec 13 for the full story.

trinitree88
2011-Dec-03, 07:19 PM
Antoniseb. Here's the initial flurry @ ~ 120 Gev/c2 SEE:http://www.science20.com/quantum_diaries_survivor/lhc_combination_higgs_limits_mh141_gev-84800



and Peter Higgs @ Easter ...... SEE:http://blog.vixra.org/2011/11/21/where-does-higgs-fit-best/


and a video of the concerns and plans from last summer....here:http://www.youtube.com/watch?v=jOn5YwrVcE8

Ivan Viehoff
2011-Dec-05, 10:53 AM
With all that data, 3-sigs come and go. There was a 4-sig something that came and went previously.

Though, as I forget who said, the most tedious possible result for the LHC was that it found the Higgs, and nothing else.

Cougar
2011-Dec-05, 02:27 PM
Rumor is that on Dec 13 they will announce an almost three sigma likely candidate for the Higgs particle at about 125 GeV.

That's well within the range of the Tevatron.

trinitree88
2011-Dec-06, 04:08 PM
That's well within the range of the Tevatron.

Cougar. Yep, that's what I've been thinking. It should have been a bump in the cross-sections there before the LHC and it wasn't....so it might disappear. I've been led astray by some stats before. We'll see. pete

trinitree88
2011-Dec-06, 05:06 PM
Cougar. Yep, that's what I've been thinking. It should have been a bump in the cross-sections there before the LHC and it wasn't....so it might disappear. I've been led astray by some stats before. We'll see. pete

here's Lubos Motl's blog on CERN stuff....SEE:http://indico.cern.ch/conferenceDisplay.py?confId=164744

and....based on a heavy Z interacting with a ( double-W)- Z....with half of each splitting off in the resonance, you could predict a final mass of ~ 125.99 Gev/c2.....and still no new particle. pete

W =~ 80.398 Gev/c2
Z = ~ 91.198 Gev/c2

80.398 W plus half the Z as a neutrino or antineutrino..45.599..(yep energy is mass) yields ~ 125.99, and the carrier of mass, the Z, is the carrier of the gravitational field as was predicted in my paper to the Grav. Research Foundation and in my talk at Williams College 1993 at the AAPT/joint APS. pete

Perikles
2011-Dec-08, 09:09 AM
I just love it when scientists try to make a general statement which is not black or white. This from the BBC:


the director of research at Cern, Sergio Bertolucci.... He told me, somewhat enigmatically: "It's too early to say…I think we may get indications that are not consistent with its non-existence."

Cougar
2011-Dec-08, 08:28 PM
This from the BBC:

Right. I noticed BBC picked up the story yesterday. Like Antoniseb's OP noted, BBC said the announcement was scheduled for Dec. 13.

BetaDust
2011-Dec-09, 07:00 AM
And from Space.com (http://www.space.com/13871-physicists-major-god-particle-announcement-week.html)

Physicists to Make Major 'God Particle' Announcement Next Week


Scientists at the Swiss lab that hosts the world's largest atom smasher, the Large Hardon Collider (LHC), will announce their latest findings in the search for an elusive subatomic particle called the Higgs boson or "God particle," next week. Already blogs and online news outlets are abuzz with speculation about the big announcement. More... (http://www.space.com/13871-physicists-major-god-particle-announcement-week.html
[URL="http://www.space.com/13871-physicists-major-god-particle-announcement-week.html)

-- Dennis

tnjrp
2011-Dec-09, 10:54 AM
And from Scientific American:
http://www.scientificamerican.com/article.cfm?id=higgs-lhc

George
2011-Dec-09, 09:12 PM
I just love it when scientists try to make a general statement which is not black or white. This from the BBC:
...the director of research at Cern, Sergio Bertolucci.... He told me, somewhat enigmatically: "It's too early to say…I think we may get indications that are not consistent with its non-existence." ... [My green.]
I could be right, but I think this might be partially hilarious..maybe.

tnjrp
2011-Dec-13, 01:32 PM
The show's on!

CERN's webcast (http://webcast.web.cern.ch/webcast/) was choked as of moments ago but Quantum Diaries still works:
http://www.quantumdiaries.org/author/aidan-randle-conde/

Strange
2011-Dec-13, 01:38 PM
There is a lot of stuff on Twitter (which, I have to say, I hardly ever look at): https://twitter.com/#!/search?q=%23Higgs


Perhaps the game "Battleships" is a good analogy for the #Higgs search. We're putting in pegs to rule out certain areas.

ToSeek
2011-Dec-13, 05:16 PM
ATLAS and CMS experiments present Higgs search status (http://press.web.cern.ch/press/PressReleases/Releases2011/PR25.11E.html)


The main conclusion is that the Standard Model Higgs boson, if it exists, is most likely to have a mass constrained to the range 116-130 GeV by the ATLAS experiment, and 115-127 GeV by CMS. Tantalising hints have been seen by both experiments in this mass region, but these are not yet strong enough to claim a discovery.

Higgs bosons, if they exist, are very short lived and can decay in many different ways. Discovery relies on observing the particles they decay into rather than the Higgs itself. Both ATLAS and CMS have analysed several decay channels, and the experiments see small excesses in the low mass region that has not yet been excluded.

Taken individually, none of these excesses is any more statistically significant than rolling a die and coming up with two sixes in a row. What is interesting is that there are multiple independent measurements pointing to the region of 124 to 126 GeV. It's far too early to say whether ATLAS and CMS have discovered the Higgs boson, but these updated results are generating a lot of interest in the particle physics community.

Cougar
2011-Dec-13, 07:30 PM
"Higgs bosons, if they exist, are very short lived and can decay in many different ways."

How do they know the various decay modes?

thoth II
2011-Dec-13, 07:44 PM
good,

they've pinned down the expected Higgs mass now and that's within it.

A major prof. of mine, David Cline was on Rubio's CERN team that made the last big experimental discovery in particle physics, the W,Z bosons and I am reminded I still have the paper. This would be great if they discovered the Higgs at last.

trinitree88
2011-Dec-13, 08:42 PM
How do they know the various decay modes?

Cougar. Computers fed with algorithms that search decays for specific characteristics like constant momentum, conservation of charge, baryon number, lepton family number, associated production in strangeness (they can violate conserving it in decays past the production point). Out of billions of events they are sorted into likely bins and the stats pile up.
They used to use photographs in bubble chambers, but the high speed of spark chambers, wire chambers, scintillators and germanium calorimeters, coupled with advances in raw computer speed makes it possible to look for more specific events much more quickly now....similar to the terabyte sorting done in galaxy surveys.
The Wiki site for Z decays gives typical stats....a certain percentage expected in a variety of channels, and it's not infinite, most of the decays are pretty routine, quark pairs...(the B/B-bar channel)/lepton pairs....the electron muon and tau with their respective antiparticle, pairs of all three types of neutrinos, hadrons (meson and baryon pairs).
Even before the LHC was up and running, calibration of the detector could be done with known cosmic ray shower activity which comes in as it runs but has incorrect momentum and can be screened out as background. pete

Jens
2011-Dec-14, 12:22 AM
Something seems strange, though. If it really is there, then why don't they get better figures? Is it just that there is insufficient data?

Shaula
2011-Dec-14, 06:17 AM
Something seems strange, though. If it really is there, then why don't they get better figures? Is it just that there is insufficient data?
More to do with the way it works, although data volumes are important. They collide stuff, remove the known decays and look for a residual signal. Because all of the events they are looking for are probabilistic you do need a lot of events to be sure that the residual is significant and not just a 'lucky' set of data. Hence the sigma results. They are giving the odds that the residual is significant, that it is not just the data playing games with them. To be very sure you need a LOT of data.

tnjrp
2011-Dec-14, 06:50 AM
I'm sure it's all just politics... :whistle:

Some commentaries shamelessly pilfered from Bad Astronomer's g+ post:
* Sean Carroll: http://blogs.discovermagazine.com/cosmicvariance/2​011/12/13/science-it-marches-on/
* Brian Greene: http://worldsciencefestival.com/blog/brian_greene_reacts_to_todays_cern_announcement
* Matt Strassler: http://profmattstrassler.com/2011/12/13/what-did-i-learn-today-during-and-after-presentation/

And one more - Lubos Motl: http://motls.blogspot.com/2011/12/higgs-17-hours-ahead-of-world.html

trinitree88
2011-Dec-27, 06:55 PM
I'm sure it's all just politics... :whistle:

Some commentaries shamelessly pilfered from Bad Astronomer's g+ post:
* Sean Carroll: http://blogs.discovermagazine.com/cosmicvariance/2​011/12/13/science-it-marches-on/
* Brian Greene: http://worldsciencefestival.com/blog/brian_greene_​reacts_to_todays_cern_announcement
* Matt Strassler: http://profmattstrassler.com/2011/12/13/what-did-i​-learn-today-during-and-after-presentation/

And one more - Lubos Motl: http://motls.blogspot.com/2011/12/higgs-17-hours-ahead-of-world.html

tnjrp. two of your links are amiss. While the graphs show a bump in activity @ ~ 126 Gev/c2, that is also consistent with the creation of two Z bosons with an asymmetrical distribution of energy. The Z from the Z-pole , slightly over 90 Gev/c2, and a much heavier Z in the form of the particle/antiparticle pair consisting of two W bosons of ~ 80 Gev each. When they interact via the neutral current, the heavy Z can split into a neutrino/antineutrino pair...George Gamow's proposed "graviton" from his text written for the Harvard Project Physics course years ago, which occurs in the diagonal of the SU(5) symmetry from Howard Georgi's 1981 article in Scientific American. As such it provides the first glimpse not only of the putative carrier of mass, but the quantum of the gravitational field. You can't create mass without a commensurate change in the ambient gravitational field. It is massless as a neutrino/antineutrino pair and travels at c, requisite to the rate of expansion of the field, as is required by GR.
The coincidences seen at the Rome/Maryland gravitational wave observatories, and the IMB, Kamiokande/ Mont Blanc/ and Baksan neutrino detectors, during supernova 1987a, also at > 3.0 sigma (Larry Sulak,IMB), were likely the result of neutral currents interacting via the same mechanism at a lower energy level. One only has to have a Milky Way galactic supernova to see it more distinctly. Merry Christmas and a Happy New Year. pete

tnjrp
2011-Dec-28, 04:54 AM
tnjrp. two of your links are amiss.Wonders of cut-and-paste, apparently. Trivially correctable however.

lpetrich
2011-Dec-29, 07:09 PM
tnjrp. two of your links are amiss. While the graphs show a bump in activity @ ~ 126 Gev/c2, that is also consistent with the creation of two Z bosons with an asymmetrical distribution of energy. The Z from the Z-pole , slightly over 90 Gev/c2, and a much heavier Z in the form of the particle/antiparticle pair consisting of two W bosons of ~ 80 Gev each.
I don't see what you are talking about. Colliding quarks with enough energy could radiate Z's, but they'd produce a continuous spectrum of reconstructed putative Higgs masses, making this process a background process.


When they interact via the neutral current, the heavy Z can split into a neutrino/antineutrino pair...George Gamow's proposed "graviton" from his text written for the Harvard Project Physics course years ago, which occurs in the diagonal of the SU(5) symmetry from Howard Georgi's 1981 article in Scientific American. ...
What a mixup. Heavy Z-like particles or Z''s are a byproduct of extensions of the Standard Model and of GUT's, but they are NOT gravitons. As to Gamow and Georgi, I would like to see their words on this subject, but I'm sure that they are sure that a Z' particle cannot be a graviton. Z''s are massive and have spin 1, the graviton is massless and has spin 2.

lpetrich
2011-Dec-29, 07:40 PM
The peaks that they found are about 2 to 3 standard deviations (sigmas) above the background, but they are nearly coincident at 125 GeV, giving their statistical significance about 3 to 4 sigmas.

That's almost but not quite the 5-sigma official discovery limit.

But physicists have already been exploring the implications of this putative discovery. [1112.3017] Implications of a 125 GeV Higgs scalar for LHC SUSY and neutralino dark matter searches (http://arxiv.org/abs/1112.3017)

Supersymmetric extensions of the Standard Model have a very large parameter space, so physicists have come up with simplifications with only a few paremters, like CMSSM / mSUGRA and NUHM2. That papers authors find that in these models, superpartners of known particles must have masses from nearly 1 TeV to a few TeV.

This means that it'll be awfully hard for the LHC to detect supersymmetric particles.

trinitree88
2011-Dec-30, 06:47 PM
I don't see what you are talking about. Colliding quarks with enough energy could radiate Z's, but they'd produce a continuous spectrum of reconstructed putative Higgs masses, making this process a background process.


What a mixup. Heavy Z-like particles or Z''s are a byproduct of extensions of the Standard Model and of GUT's, but they are NOT gravitons. As to Gamow and Georgi, I would like to see their words on this subject, but I'm sure that they are sure that a Z' particle cannot be a graviton. Z''s are massive and have spin 1, the graviton is massless and has spin 2.


Ipetrich. The Z can be any particle/antiparticle pair. At high energy, the pairs may be massive, but neutral currents were seen at Gargamelle, where knock-on electrons appeared...ghostlike...in tanks of supercritical hydrogen. No incoming or exiting particle was seen, indicating that a neutrino had emitted a Z which interacted, via the neutral current (a Z)...and left the tank.This is not prohibited at low energy, and below 1.022 Mev/c2 it can [color]only[/color is red] be neutrino/antineutrino or photon/photon. As such, it's Gamow's graviton.

Tensor
2011-Dec-30, 07:25 PM
Ipetrich. The Z can be any particle/antiparticle pair. At high energy, the pairs may be massive, but neutral currents were seen at Gargamelle, where knock-on electrons appeared...ghostlike...in tanks of supercritical hydrogen. No incoming or exiting particle was seen, indicating that a neutrino had emitted a Z which interacted, via the neutral current (a Z)...and left the tank.This is not prohibited at low energy, and below 1.022 Mev/c2 it can [color]only[/color is red] be neutrino/antineutrino or photon/photon. As such, it's Gamow's graviton.

It can't be Gamow's graviton. Georgi and Glashow's SU(5) has been eliminated as possible by proton decay. Their SU(5) predicted proton decay half-life of 1031 years, current measurements indicate that the proton has a half-life of, at least, 1032 years. SU(5) can still be part of a GUT under SO(10) or a Flipped SU(5), but Georgi and Glashow's doesn't work. And if Gamow is taking his graviton off of Georgi and Glashow's work, well, you can see the problem.

lpetrich
2011-Dec-31, 05:41 AM
Ipetrich. The Z can be any particle/antiparticle pair.
It cannot "be" a particle/antiparticle pair, but it can *make* most Standard-Model particle-antiparticle pairs. There's a BIG difference between the two.


... As such, it's Gamow's graviton.
The Z cannot be a graviton. The Z has spin 1 and a mass of 91 GeV, while the graviton has spin 2 and is massless.

trinitree88
2011-Dec-31, 05:27 PM
It can't be Gamow's graviton. Georgi and Glashow's SU(5) has been eliminated as possible by proton decay. Their SU(5) predicted proton decay half-life of 1031 years, current measurements indicate that the proton has a half-life of, at least, 1032 years. SU(5) can still be part of a GUT under SO(10) or a Flipped SU(5), but Georgi and Glashow's doesn't work. And if Gamow is taking his graviton off of Georgi and Glashow's work, well, you can see the problem.

Tensor. The failure to see proton decay eliminated the X particle....the putative leptoquark boson that allowed a fermion to convert into a lepton in two sets of 6interactions...no? The remainder of the interactions were correctly modeled ...gluons for quantum chromodynamics, the W's for weak interactions, photons for electromagnetic, and Z's universally...acting on all the right-handed members across the diagonal. pete
edit: In essence, it predicts that an increase in the ambient flux of the neutrino sea from a particular direction, regardless of energy level (though the cross-sections vary as E2), will result in an increase in the probability of the interaction rate (flux...phi, times sigma...) and be correspondingly felt as an increase in the ambient gravitational field. When SN1987a's prompt neutrino pulses set off the six detectors simultaneously @ ~ 3.2 sigma, it confirmed my prediction from my paper from April of 1982....same level as the recent news from the LHC. It did get me a standing ovation at Williams College in 93, along with the introduction of the trinity of equivalence, but some people remain in denial and have pretty short memories, and I am remineded that S. Chandrasekhar refused to speak publicly for ~ 10 years, though correct, on black holes after a public chastising by Eddington, an accomplished,authoritatively positioned astrophysicist...but who nevertheless was wrong on that one. C'est la vie. pete

trinitree88
2012-Jan-04, 07:22 PM
Tensor. The failure to see proton decay eliminated the X particle....the putative leptoquark boson that allowed a fermion to convert into a lepton in two sets of 6interactions...no? The remainder of the interactions were correctly modeled ...gluons for quantum chromodynamics, the W's for weak interactions, photons for electromagnetic, and Z's universally...acting on all the right-handed members across the diagonal. pete
edit: In essence, it predicts that an increase in the ambient flux of the neutrino sea from a particular direction, regardless of energy level (though the cross-sections vary as E2), will result in an increase in the probability of the interaction rate (flux...phi, times sigma...) and be correspondingly felt as an increase in the ambient gravitational field. When SN1987a's prompt neutrino pulses set off the six detectors simultaneously @ ~ 3.2 sigma, it confirmed my prediction from my paper from April of 1982....same level as the recent news from the LHC. It did get me a standing ovation at Williams College in 93, along with the introduction of the trinity of equivalence, but some people remain in denial and have pretty short memories, and I am reminded that S. Chandrasekhar refused to speak publicly for ~ 10 years, though correct, on black holes after a public chastising by Eddington, an accomplished,authoritatively positioned astrophysicist...but who nevertheless was wrong on that one. C'est la vie. pete edit typo