OMEGA
New member
"God Particle" Found? :sheep:
"Historic Milestone" From Higgs Boson Hunters
New particle may be at the core of existence.
In an artist's conception, a Higgs boson erupts from a collision of
protons.
Published July 4, 2012
"I think we have it. You agree?"Speaking to a packed audience Wednesday morning
in Geneva, CERN director general Rolf Heuer confirmed that two separate teams
working at the Large Hadron Collider (LHC) are more than 99 percent certain
they've discovered the Higgs boson, aka the God particle—or at the least a
brand-new particle exactly where they expected the Higgs to be.
The long-sought particle may complete the standard model of physics by
explaining why objects in our universe have mass—and in so doing, why galaxies,
planets, and even humans have any right to exist.
(See Large Hadron Collider pictures.)
"We have a discovery," Heuer said at the seminar. "We have observed a new
particle consistent with a Higgs boson."
At the meeting were four theorists who helped develop the Higgs theory in the
1960s, including Peter Higgs himself, who could be seen wiping away tears as the
announcement was made.
Although preliminary, the results show a so-called five-sigma of significance,
which means that there is only a one in a million chance that the Higgs-like
signal the teams observed is a statistical fluke.
"It's a tremendous and exciting time," said physicist Michael Tuts, who works
with the ATLAS (A Toroidal LHC Apparatus) Experiment, one of the two
Higgs-seeking LHC projects.
The Columbia University physicist had organized a wee-hours gathering of
physicists and students in the U.S. to watch the announcement, which took place
at 9 a.m., Geneva time.
"This is the payoff. This is what you do it for."
The two LHC teams searching for the Higgs—the other being the CMS (Compact Muon
Solenoid) project—did so independently. Neither one knew what the other would
present this morning.
"It was interesting that the competing experiment essentially had the same
result," said physicist Ryszard Stroynowski, an ATLAS team member based at
Southern Methodist University in Dallas. "It provides additional confirmation."
CERN head Heuer called today's announcement a "historic milestone" but cautioned
that much work lies ahead as physicists attempt to confirm the newfound
particle's identity and further probe its properties.
For example, though the teams are certain the new particle has the proper mass
for the predicted Higgs boson, they still need to determine whether it behaves
as the God particle is thought to behave—and therefore what its role in the
creation and maintenance of the universe is.
"I think we can all be proud ... but it's a beginning," Heuer said.
Higgs Boson Results Exceeded Expectations
The five-sigma results from both the ATLAS and CMS experiments exceeded the
expectations of many physicists, including David Evans, leader of the U.K. team
that works on the LHC-based ALICE (A Large Ion Collider Experiment)
Collaboration.
Evans had predicted Tuesday the teams would announce a four-sigma result—just
short of the rigorous standard traditionally required for a new-particle
observation to officially count as a true discovery and not a fluke.
"It's even better than I expected," said Evans, of the University of Birmingham
in the U.K. "I think we can say the Higgs is here. It exists."
Evans attributed the stronger-than-expected results to "a mixture of the LHC
doing a fantastic job" and "ATLAS and CMS doing a fantastic job of improving
their analysis since December," when the two teams announced a two-sigma
observation of signs of a Higgs-like particle.
"So even with the same data, they can get more significance."
ATLAS spokesperson Fabiola Gianotti also had high praise for the LHC, a
multibillion-dollar machine that had suffered numerous mishaps and setbacks in
its early days. (Related: "Electrical Glitch Delays Large Hadron Collider.")
"The LHC and experiments have been doing miracles. I think we are working beyond
design," the Italian particle physicist added.
ALICE's Evans said he was extremely pleased by the Higgs results but admitted
feeling just a bit disappointed that the results weren't more surprising.
"Secretly I would have loved it to be something slightly different than the
standard model predictions, because that would indicate that there's something
more out there."
On God-Particle Hunt, It's "Easy to Fool Yourself"
Wednesday's announcement builds on results from last December, when the ATLAS
and CMS teams said their data suggested that the Higgs boson has a mass of about
125 gigaelectron volts (GeV)—about 125 times the mass of a proton, a positively
charged particle in an atom's nucleus.
(See "Hints of Higgs Boson Seen at LHC—Proof by Next Summer?")
"For the first time there was a case where we expected to [rule out] the Higgs,
and we weren't able to do so," said Tim Barklow, an experimental physicist with
the ATLAS Experiment who's based at Stanford University's SLAC National
Accelerator Laboratory.
A two-sigma finding translates to about a 95 percent chance that results are not
due to a statistical fluke.
While that might seem impressive, it falls short of the stringent five-sigma
level that high-energy physicists traditionally require for an official
discovery. Five sigma means there's a less than one in a million probability
that a finding is due to chance.
"We make these rules and impose them on ourselves because, when you are
exploring on the frontier, it is easy to fool yourself," said Michael Peskin, a
theoretical physicist also at SLAC.
(Related: "'God Particle' May Be Five Distinct Particles, New Evidence Shows.")
Higgs Holds It All Together?
The Higgs boson is one of the final puzzle pieces required for a complete
understanding of the standard model of physics—the so-far successful theory that
explains how fundamental particles interact with the elementary forces of
nature.
The so-called God particle was proposed in the 1960s by Peter Higgs to explain
why some particles, such as quarks—building blocks of protons, among other
things—and electrons have mass, while others, such as the light-carrying photon
particle, do not.
Higgs's idea was that the universe is bathed in an invisible field similar to a
magnetic field. Every particle feels this field—now known as the Higgs field—but
to varying degrees.
If a particle can move through this field with little or no interaction, there
will be no drag, and that particle will have little or no mass. Alternatively,
if a particle interacts significantly with the Higgs field, it will have a
higher mass.
The idea of the Higgs field requires the acceptance of a related particle: the
Higgs boson.
According to the standard model, if the Higgs field didn't exist, the universe
would be a very different place, said SLAC's Peskin, who isn't involved in the
LHC experiments.
"It would be very difficult to form atoms," Peskin said. "So our orderly world,
where matter is made of atoms, and electrons form chemical bonds—we wouldn't
have that if we did not have the Higgs field."
In other words: no galaxies, no stars, no planets, no life on Earth.
"Nature Is Really Nasty" to Higgs Boson Seekers
Buried beneath the French-Swiss border, the Large Hadron Collider is essentially
a 17-mile-long (27-kilometer-long) oval tunnel. Inside, counter-rotating beams
of protons are boosted to nearly the speed of light using an electric field
before being magnetically steered into collisions.
Exotic fundamental particles—some of which likely haven't existed since the
early moments after the big bang—are created in the high-energy crashes. But the
odd particles hang around for only fractions of a second before decaying into
other particles.
(Also see "Strange Particle Created; May Rewrite How Matter's Made.")
Theory predicts that the Higgs boson's existence is too fleeting to be recorded
by LHC instruments, but physicists think they can confirm its creation if they
can spot the particles it decays into. (Explore a Higgs boson interactive.)
Now that the Higgs boson—or something like it—has been confirmed to indeed have
a mass of around 125 to 126 GeV, scientists have a better idea why the God
particle has avoided detection for so long.
This mass is just high enough to be out of reach of earlier, lower-energy
particle accelerators, such as the LHC's predecessor, the Large
Electron-Positron Collider, which could probe to only about 115 GeV.
At the same time 125 GeV is not so massive that it produces decay products so
unusual that their detection would be clear proof of the Higgs's existence.
In reality the Higgs appears to transform into relatively commonplace decay
products such as quarks, which are produced by the millions at the LHC.
"It just so happens that nature is really nasty to us, and the range that we've
narrowed [the Higgs] down to is the range that makes it most difficult to find,"
==================================================
"Historic Milestone" From Higgs Boson Hunters
New particle may be at the core of existence.
In an artist's conception, a Higgs boson erupts from a collision of
protons.
Published July 4, 2012
"I think we have it. You agree?"Speaking to a packed audience Wednesday morning
in Geneva, CERN director general Rolf Heuer confirmed that two separate teams
working at the Large Hadron Collider (LHC) are more than 99 percent certain
they've discovered the Higgs boson, aka the God particle—or at the least a
brand-new particle exactly where they expected the Higgs to be.
The long-sought particle may complete the standard model of physics by
explaining why objects in our universe have mass—and in so doing, why galaxies,
planets, and even humans have any right to exist.
(See Large Hadron Collider pictures.)
"We have a discovery," Heuer said at the seminar. "We have observed a new
particle consistent with a Higgs boson."
At the meeting were four theorists who helped develop the Higgs theory in the
1960s, including Peter Higgs himself, who could be seen wiping away tears as the
announcement was made.
Although preliminary, the results show a so-called five-sigma of significance,
which means that there is only a one in a million chance that the Higgs-like
signal the teams observed is a statistical fluke.
"It's a tremendous and exciting time," said physicist Michael Tuts, who works
with the ATLAS (A Toroidal LHC Apparatus) Experiment, one of the two
Higgs-seeking LHC projects.
The Columbia University physicist had organized a wee-hours gathering of
physicists and students in the U.S. to watch the announcement, which took place
at 9 a.m., Geneva time.
"This is the payoff. This is what you do it for."
The two LHC teams searching for the Higgs—the other being the CMS (Compact Muon
Solenoid) project—did so independently. Neither one knew what the other would
present this morning.
"It was interesting that the competing experiment essentially had the same
result," said physicist Ryszard Stroynowski, an ATLAS team member based at
Southern Methodist University in Dallas. "It provides additional confirmation."
CERN head Heuer called today's announcement a "historic milestone" but cautioned
that much work lies ahead as physicists attempt to confirm the newfound
particle's identity and further probe its properties.
For example, though the teams are certain the new particle has the proper mass
for the predicted Higgs boson, they still need to determine whether it behaves
as the God particle is thought to behave—and therefore what its role in the
creation and maintenance of the universe is.
"I think we can all be proud ... but it's a beginning," Heuer said.
Higgs Boson Results Exceeded Expectations
The five-sigma results from both the ATLAS and CMS experiments exceeded the
expectations of many physicists, including David Evans, leader of the U.K. team
that works on the LHC-based ALICE (A Large Ion Collider Experiment)
Collaboration.
Evans had predicted Tuesday the teams would announce a four-sigma result—just
short of the rigorous standard traditionally required for a new-particle
observation to officially count as a true discovery and not a fluke.
"It's even better than I expected," said Evans, of the University of Birmingham
in the U.K. "I think we can say the Higgs is here. It exists."
Evans attributed the stronger-than-expected results to "a mixture of the LHC
doing a fantastic job" and "ATLAS and CMS doing a fantastic job of improving
their analysis since December," when the two teams announced a two-sigma
observation of signs of a Higgs-like particle.
"So even with the same data, they can get more significance."
ATLAS spokesperson Fabiola Gianotti also had high praise for the LHC, a
multibillion-dollar machine that had suffered numerous mishaps and setbacks in
its early days. (Related: "Electrical Glitch Delays Large Hadron Collider.")
"The LHC and experiments have been doing miracles. I think we are working beyond
design," the Italian particle physicist added.
ALICE's Evans said he was extremely pleased by the Higgs results but admitted
feeling just a bit disappointed that the results weren't more surprising.
"Secretly I would have loved it to be something slightly different than the
standard model predictions, because that would indicate that there's something
more out there."
On God-Particle Hunt, It's "Easy to Fool Yourself"
Wednesday's announcement builds on results from last December, when the ATLAS
and CMS teams said their data suggested that the Higgs boson has a mass of about
125 gigaelectron volts (GeV)—about 125 times the mass of a proton, a positively
charged particle in an atom's nucleus.
(See "Hints of Higgs Boson Seen at LHC—Proof by Next Summer?")
"For the first time there was a case where we expected to [rule out] the Higgs,
and we weren't able to do so," said Tim Barklow, an experimental physicist with
the ATLAS Experiment who's based at Stanford University's SLAC National
Accelerator Laboratory.
A two-sigma finding translates to about a 95 percent chance that results are not
due to a statistical fluke.
While that might seem impressive, it falls short of the stringent five-sigma
level that high-energy physicists traditionally require for an official
discovery. Five sigma means there's a less than one in a million probability
that a finding is due to chance.
"We make these rules and impose them on ourselves because, when you are
exploring on the frontier, it is easy to fool yourself," said Michael Peskin, a
theoretical physicist also at SLAC.
(Related: "'God Particle' May Be Five Distinct Particles, New Evidence Shows.")
Higgs Holds It All Together?
The Higgs boson is one of the final puzzle pieces required for a complete
understanding of the standard model of physics—the so-far successful theory that
explains how fundamental particles interact with the elementary forces of
nature.
The so-called God particle was proposed in the 1960s by Peter Higgs to explain
why some particles, such as quarks—building blocks of protons, among other
things—and electrons have mass, while others, such as the light-carrying photon
particle, do not.
Higgs's idea was that the universe is bathed in an invisible field similar to a
magnetic field. Every particle feels this field—now known as the Higgs field—but
to varying degrees.
If a particle can move through this field with little or no interaction, there
will be no drag, and that particle will have little or no mass. Alternatively,
if a particle interacts significantly with the Higgs field, it will have a
higher mass.
The idea of the Higgs field requires the acceptance of a related particle: the
Higgs boson.
According to the standard model, if the Higgs field didn't exist, the universe
would be a very different place, said SLAC's Peskin, who isn't involved in the
LHC experiments.
"It would be very difficult to form atoms," Peskin said. "So our orderly world,
where matter is made of atoms, and electrons form chemical bonds—we wouldn't
have that if we did not have the Higgs field."
In other words: no galaxies, no stars, no planets, no life on Earth.
"Nature Is Really Nasty" to Higgs Boson Seekers
Buried beneath the French-Swiss border, the Large Hadron Collider is essentially
a 17-mile-long (27-kilometer-long) oval tunnel. Inside, counter-rotating beams
of protons are boosted to nearly the speed of light using an electric field
before being magnetically steered into collisions.
Exotic fundamental particles—some of which likely haven't existed since the
early moments after the big bang—are created in the high-energy crashes. But the
odd particles hang around for only fractions of a second before decaying into
other particles.
(Also see "Strange Particle Created; May Rewrite How Matter's Made.")
Theory predicts that the Higgs boson's existence is too fleeting to be recorded
by LHC instruments, but physicists think they can confirm its creation if they
can spot the particles it decays into. (Explore a Higgs boson interactive.)
Now that the Higgs boson—or something like it—has been confirmed to indeed have
a mass of around 125 to 126 GeV, scientists have a better idea why the God
particle has avoided detection for so long.
This mass is just high enough to be out of reach of earlier, lower-energy
particle accelerators, such as the LHC's predecessor, the Large
Electron-Positron Collider, which could probe to only about 115 GeV.
At the same time 125 GeV is not so massive that it produces decay products so
unusual that their detection would be clear proof of the Higgs's existence.
In reality the Higgs appears to transform into relatively commonplace decay
products such as quarks, which are produced by the millions at the LHC.
"It just so happens that nature is really nasty to us, and the range that we've
narrowed [the Higgs] down to is the range that makes it most difficult to find,"
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