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Tag search results for: "relive"
What Is Dead? (by Philip E. Gibbs): Abstract: There is a lot of interesting talk around the blogs about the fate of SUSY and even the whole field of phenomenology. It is a fascinating debate.

Comparing Combos (by Philip E. Gibbs): Abstract: The Tevatron Higgs Combination is up, so time to compare with my prediction.

Higgs Combination and Fits Revisited (by Philip E. Gibbs): Abstract: Now that the Tevatron Higgs combination is public and I can see how much error there is in the direct combination process, it seems like a good idea to redo my earlier combinations. I know lots of people are interested to see these now to give information about where we stand.

Higgs Combos, Global Fit, the Dead, the Alive & the New (by Philip E. Gibbs): Abstract: If we accept the combination uncertainty estimate and the statistical validity of combining all direct searches with electroweak fits: We indirectly rule out a lone standard model Higgs boson of any mass with no additional BSM physics at 90% confidence, i.e. a fair bit short of conclusively. We directly rule out any standard model Higgs boson at 95% confidence except in the mass ranges 114GeV to 144GeV or 240 GeV to 265 GeV or above 480 GeV. We do not rule out other BSM Higgs-type mechanisms including composite Higgs, technicolor Higgs, Higgs doublets, SUSY Higgs etc. We do not rule out high-mass Higgs bosons above 480 GeV in combination with other BSM physics that could explain electroweak fits and cure theoretical limitations of the SM at higher energies. We see excesses at around 130 GeV to around 160 GeV that could be between two and three sigma level. It might suggest some new physics such as some kind of Higgs particle(s) in this region. However, these are not high levels of statistical significance.

Administrator · Jul 20 '12 · Tags: 2011, particle physics, relive
SUSY Was Not Around the Corner (by Philip E. Gibbs): Abstract: ATLAS has produced new exclusions limits for SUSY (Taffard) models using jets plus missing transverse energy from 1/fb of data. These go well beyond previous limits leading to the conclusion that “SUSY” was NOT “just rounnd the corner” as theorists hoped.

Big Day for Higgs Boson (by Philip E. Gibbs): Abstract: Today at the EPS conference in Grenoble the world’s largest hadron colliders will be revealing the results of their latest searches for the Higgs boson, using data collected up until the last few weeks. We will be posting the plots here as they appear. The individual experiments Dzero, CDF, ATLAS and CMS will each show their all channel combined plots. There will also be separated plots for individual channels and some separate searches for a charged Higgs as predicted in some models such as MSSM.

Higgs Combos (by Philip E. Gibbs): Abstract: Some people have been asking if confidence level plots can be combined now that we have the individual data from Dzero, CDF, ATLAS and CMS. The answer is of course not. You need to combine the underlying event data and all the backgrounds etc., and re-derive the levels from that.

Global Fit Kills (or at least Wounds) the Standard Model (by Philip E. Gibbs): Abstract: A few days ago I showed how to combine the Higgs confidence level plots by adding in inverse square. At the time I did not understand why this worked (I am a bit slow at statistics.) Since then I have looked again at the work on electroweak precision tests and the global fit where you can find the same calculation being done. The inverse square of the 95% confidence level limits is just one-quarter of the Δχ2 estimator. For independent variables these can be directly added to give an overall Δχ2 which can then be mapped back to an overall confidence level limit. This is exactly what I was doing in my combinations. So now I know that these combo plots are essentially correct, neglecting any correlations which should be zero.

Administrator · Jul 19 '12 · Tags: 2011, particle physics, relive
EPS Early Posters Showing Up to 1.21/fb from ATLAS (by Philip E. Gibbs): Abstract: The Europhysics HEP conference (EPS) starts in earnest on July 22, 2011 with a good chance that some very strong results on Higgs searches will be revealed. There is likely to be either a plausible signal or an extensive exclusion, and maybe both.

Higgs Update from D0 and CDF (by Philip E. Gibbs): Abstract: This is a Higgs Update from D0 and CDF. The small amount of additional data helps to extend the exclusion range, but we will need to see a combination with CDF to get the best limits.

CDF Report 327 GeV Anomaly in 4l Channel (by Philip E. Gibbs): Abstract: In a presentation at EPS-HEP today CFD will show a surprising cluster of 4 events in the 4 lepton “golden channel” consistent with a particle at 327GeV.

Highlights of EPS First Morning (by Philip E. Gibbs): Abstract: Undoubtedly the most talked about presentation so far will be the CDF search for ZZ resonances (Robson) with the below striking peek at 327 GeV. This is the only talk so far that has not seen everything consistent with standard model. The talks themselves have not been broadcast so we only have the slides to go by. It would be nice to know what questions were asked at this one.

Administrator · Jul 18 '12 · Tags: 2011, particle physics, relive
Exciting New Era of Particle Physics (by Philip E. Gibbs): Abstract: I don’t think there has ever been a moment quite like this in physics before. Within the next few months, weeks or even days we will learn something new about the universe that will change our thinking forever. I don’t mean something like a little CP asymmetry or a new observation of neutrino physics. These things are great but they just pose questions that we cannot answer yet. What we are about to learn is going to generate so many new ideas in physics that the arXiv will run out of four digit numbers so that people have to start posting their papers in viXra. Am I exaggerating? Let us see take a look.

The Dawn of a Brave New World in Particle Physics (by Huping Hu, Maoxin Wu): Abstract: This issue of Prespacetime Journal celebrates the great success of LHC and Tevatron through a series of Special Reports written by Philip Gibbs, several Editorials and other regular pieces. All people associated with LHC and Tevatron deserve our special thanks. We are in the super-connected Age of Internet and technological wonders made possible through science. There is no doubt that we are also at the dawn of a brave New World in particle physics and science overall. Every genuine truth seeker should seize this moment. Here we briefly discuss: (1) the great unknown in light of the great success of LHC and Tevatron, (2) Higgsless models published in this journal; and (3) the search for the genuine “God Particle.” What we have witnessed so far is the rise of collaborative spirit in physics. We urge all genuine truth seekers to work together to make the brave New World a reality. We conclude with a poem “A Praise to Prespacetime.”

Physics in a Higgsless World (by Lawrence B. Crowell): Abstract: The ATLAS and CMS data is giving a 2-σ exclusion on the light Higgs fields in the 110 -140GeV energy scale. This is a 95% probability of no signal from the Higgs field. The data so far is lack luster for those who promote Higgsian theories, but we are at about 1/1000 the total data expected, so there are lot more to come. In light of the foregoing, the author discusses here Higgsless alternatives. Clearly the time we live in currently is interesting, and we may be in a time where our understanding of the foundations of physics might radically change. The one advantage of living in a time where a lot of physical theory is falsified is that it clears the way for different modes of thought.

The Aftermath of Europhysics 2011 (by Matti Pitkänen): Abstract: In this Guest Editorial, some alternative visions about the physics after Europhysics 2011 are discussed.

Administrator · Jul 17 '12 · Tags: 2011, particle physics, relive