* Astronomy

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RE: Higgs Particles

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Cern scientist expects 'first glimpse' of Higgs boson

A respected scientist from the Cern particle physics laboratory has told the BBC he expects to see "the first glimpse" of the Higgs boson next week.
It comes as the search for the mysterious fundamental particle reaches its endgame.
The teams have been focussing-in on the Higgs by ruling out energy ranges where it might be lurking. They now expect to see it at around 120 to 125 GeV (gigelectronvolts), where one GeV is about the mass of a proton.
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Title: Invisible Higgs and Scalar Dark Matter
Authors: Y. Mambrini

In this proceeding, we show that when we combined WMAP and the most recent results of XENON100, the invisible width of the Higgs to scalar dark matter is negligible(<10%), except in a small region with very light dark matter (< 10 GeV) not yet excluded by XENON100 or around 60 GeV where the ratio can reach 50% to 60%. The new results released by the Higgs searches of ATLAS and CMS set very strong limits on the elastic scattering cross section.

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'Moment of truth' approaching in Higgs boson hunt

Earlier this month, physicists announced results of a combined search for the Higgs by the Atlas and CMS experiments at the Large Hadron Collider (LHC).
Their analysis, presented at a meeting in Paris, shows that physicists have now covered a large chunk of the search area in detail, ruling out a broad part of the mass range where the boson could be lurking.
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Higgs Boson hunt '80% complete'

Scientists at Cern will be able to say whether the Higgs Boson exists or not within one year, according to physicist Jon Butterworth.
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Public Lecture - Hunting the Elusive Higgs Boson and the Origin of Mass

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Title: Evasive Higgs Manoeuvres at the LHC
Authors: Christoph Englert, Joerg Jaeckel, Emanuele Re, Michael Spannowsky

Non-standard decays of the Higgs boson produced at the Large Hadron Collider can lead to signatures which can easily be missed due to non-adapted trigger or search strategies. Keeping electroweak symmetry breaking Standard Model-like we classify the phenomenology of an evasive Higgs boson into three categories and discuss how they can be described in an effective field theory. We comment on how one can improve the search strategies to also detect such an evasive Higgs.

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Title: Higgs-Dilaton Cosmology: From the Early to the Late Universe
Authors: Juan García-Bellido, Javier Rubio, Mikhail Shaposhnikov, Daniel Zenhäusern

We consider a minimal scale-invariant extension of the Standard Model of particle physics combined with Unimodular Gravity formulated in Shaposhnikov:2008xb. This theory is able to describe not only an inflationary stage, related to the Standard Model Higgs field, but also a late period of Dark Energy domination, associated with an almost massless dilaton. A number of parameters can be fixed by inflationary physics, allowing to make specific predictions for any subsequent period. In particular, we derive a relation between the tilt of the primordial spectrum of scalar fluctuations, n_s, and the present value of the equation of state parameter of dark energy, omega_{DE}^0. We find bounds for the scalar tilt, n_s<0.97, the associated running, -0.0006<d\ln n_s/d\ln k\lesssim-0.00015, and for the scalar-to-tensor ratio, 0.0009\lesssim r<0.0033, which will be critically tested by the results of the Planck mission. For the equation of state of dark energy, the model predicts omega_{DE}^0>-1. The relation between n_s and omega_{DE}^0 allows us to use the current observational bounds on n_s to further constrain the dark energy equation of state to 0< 1+\omega_{DE}^0< 0.02, which is to be confronted with future dark energy surveys.

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Higgs particle could be found by Christmas

The hunt for the Higgs particle is well ahead of schedule, say researchers at the Large Hadron Collider (LHC).
Earlier this year they said they would either discover the Higgs or confirm it does not exist by the end of 2012.
Now, because the machine is working so well, an LHC spokesman, Professor Guido Tonelli, has told BBC News that the search could be completed much sooner.
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Higgs boson range narrows at European collider

Scientists at the Large Hadron Collider say a signal that suggested they might have seen "hints" of the long-sought Higgs boson particle has weakened.
New results to be presented this week at a conference in India all but eliminate the mid-range where the Higgs - if it exists - might be found.
Physicists will now search for the boson at lower and higher energy ranges.
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