Brown University researchers are heavily Space Telescope in particular, and looking at
involved in the study of the properties of this dark matter on Earth in very deep underground
new particle. labs using Xenon-based detectors.
The actual discovery of the Higgs boson on The current search for dark matter could
July 4, 2012 has been the apex of the LHC build on a potential discovery made by Brown
program and one of the most important physicist Savvas Koushiappas, who recently
physics discoveries of this century. Its detected a potential gamma-ray signal from
discovery occurred when the LHC’s CMS and a dwarf galaxy that could be the result of
ATLAS experiments each announced that dark matter particles at the galaxy’s center
they had observed a new particle (Landsberg, slamming into each other and annihilating into
Narain, Heintz and Cutts all played important gamma rays and quarks. It could be possible
roles in this historic and successful search). to produce the same reaction in reverse at
Despite the fact that the Higgs boson particle the LHC. Instead of two dark matter particles
was found nearly at the place it was expected annihilating to produce quarks, the LHC may
to be, and its properties were very similar to be able to take a pair of quarks and annihilate
what theories predicted, its discovery yielded them to produce dark matter particles.
more questions than answers. Researchers are
now seeking to answer questions such as what
gives the Higgs boson its mass?
Other theoretical concepts that Brown
researchers are involved in include
supersymmetry (every particle that is known
around a giant solenoid magnet that generates First predicted in the 1960s, the Higgs boson, Explaining the now observed properties of has a partner that has slightly different
a field of four tesla — about 100,000 times the sometimes referred to as the “God Particle,” the Higgs boson has led researchers to seek properties) and extra dimensional theory
magnetic field of Earth. is one of the cornerstones of particle physics explanations outside of the Standard Model. (where the universe has more dimensions).
and the Standard Model because it is believed Among the new areas of research that Brown Brown is investigating all of these important
to give mass to very fundamental particles like is immersed in is looking for other particles topics and attempting to go beyond the
electrons, which impacts the atom as we know that could explain the properties of the Higgs standard model — potentially discovering
it. At the instant of the “Big Bang,” nothing had boson. Other explanations could lie in dark something completely new.
mass, not even the electron. As the universe matter, one of the hottest areas of exploration expanded and cooled down, the Higgs boson’s in physics today. Dark matter is invisible to the interaction with particles is what gave them electromagnetic spectrum, but it is believed to mass. This means that all other particles got make up most of the universe. Dark matter is their mass right after the Big Bang. truly a mystery but it is quite likely that missing
PUSHING BEYOND THE STANDARD
MODEL TO MAKE NEW DISCOVERIES
The current Standard Model of particle physics
is a theory that describes how the universe
was created out of basic building blocks of
fundamental particles, and provides the rules
for how these particles behave through the
fundamental forces (strong force, weak force
and electromagnetic force). Although the One of the theoretical founders of Higgs boson
Standard Model is currently the best over half a century ago was Gerald Guralnik,
description that exists of the subatomic Chancellor’s Professor of Physics at Brown
world, there are many important University, who was behind the theoretical
unanswered questions. research that led to its discovery. Current
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clues may be of particle physics origin, in which
case researchers may be able to detect dark
matter at colliders such as the LHC. Brown is
also involved in the research of dark matter in
space, via telescopes such as Fermi Gamma-ray
DATA PIONEERS
The LHC/CMS experiments involve a giant
digital camera taking 3D pictures of an
environment similar to the universe shortly
after the Big Bang, at a rate of 40 million
pictures per second. The data resulting from
those experiments is close to 100 million pixels
per frame! This unbiased data may potentially
produce everything from Higgs bosons, to dark
Stronger Together
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