The Higgs Boson May Disintegrate into Dark Matter

The hunt for the source of dark matter is one of the most hotly anticipated searches of our time and the Higgs boson might be able to light the way to a possible dark matter discovery.

The hunt for the source of dark matter is one of the most hotly anticipated searches of our time and the Higgs boson might be able to light the way to a possible dark matter discovery.

VIDEO: Large Hadron Collider Reboot Ready to Rumble

Confirmation of a Higgs boson discovery came in 2012 after a multi-decade search. Theorized in the 1960′s, experiments at CERN's Large Hadron Collider (LHC) near Geneva, Switzerland, decades later confirmed the particle's decay signature, eventually leading to the 2013 Nobel Prize for Physics being awarded to Peter Higgs and François Englert, two of the key physicists who laid out the theoretical framework for the particle.

As we already know, the Higgs particle mediates the Higgs field, which endows all matter with mass. The discovery of the Higgs boson at the LHC was the last "missing piece" of the Standard Model of physics. The Standard Model governs our understanding of the quantum world; it's a recipe book of sorts that enables us to understand how subatomic particles and forces interact on the smallest of scales.

However, though the basic framework of the Standard Model works for most of our purposes, it is not an all-encompassing model. Most notably, the Standard Model does not incorporate gravity - obviously a very important omission. Also, the Standard Model does not predict the source of mysterious dark matter - a fact that is growing more contentious by the day.

ANALYSIS: LHC Uncovers New Higgs Boson Decay Mechanism

Cosmological studies predict that 84.5 percent of the universe is composed of matter that can exert a gravitational force and yet does not interact with the electromagnetic force. It is a type of matter - known as non-baryonic matter - that cannot be seen, but its effects become extremely obvious when observing the gravitational effects in galactic clusters, for example. It's out there, we're certain of it, but we just can't see it and therefore cannot fully understand its nature.

There are many theories suggesting different exotic sources of dark matter, but a new model put forward by a team headed by theoretical particle physicist Christoffer Petersson, of Chalmers University of Technology in Sweden, will be tested at the LHC when it is restarted this spring.

Petersson suggests that the Higgs boson may decay in an alternative way than what has been observed to date; a decay path that is governed by supersymmetry.

Supersymmetry predicts that there are more massive "super partners" of known particles that exist beyond the Standard Model framework. Although there have been tantalizing hints of these supersymmetric particles, definitive observational evidence has been frustratingly hard to track down.

ANALYSIS: LHC Discovery Maims Supersymmetry, Again

But in the LHC's new phase of operations, where particle collisions will be boosted to record energies, evidence of supersymmetry may be more forthcoming. And this is where the Higgs comes in.

The LHC's detectors didn't directly ‘see' a Higgs boson when it made its discovery. The ATLAS and CMS detectors, over countless billions of particle collisions, slowly built up a picture of post-collision particles that sprayed away from the energy generated after counter-rotating protons smashed into one another. From this collision energy, Higgs boson particles condensed in isolation but rapidly decayed into other particles that the detectors could measure, such as muons (the electron's more massive cousin). This provided a Higgs ‘fingerprint' of sorts, evidence that Higgs bosons are being generated.

Now Petersson's team has suggested that, if supersymmetry is real, the Higgs boson may have another mode of decay, disintegrating into photons and dark matter particles. And the LHC's ATLAS and CMS experiments are on the look-out for this theorized decay mechanism.

"It's a dream for a theorist in particle physics. LHC is the only place where the model can be tested," said Petersson. "It's even nicer that two independent experiments are going to do it.

"If the model is found to fit, it would completely change our understanding of the fundamental building blocks of nature. If not, just the fact that they are willing to test my model at CERN is great."

Source: Chalmers University of Technology via Physorg.com

Computer simulation showing particle tracks inside the LHC's detectors after a Higgs boson decays.

Every year at Discovery News we reach out to our loyal readers to find out what

their

favorite space stories were for 2013. These aren't necessarily the biggest science stories nor the biggest discoveries; they are the stories that engaged

YOU

over the past 12 months. 2013 has been nothing short of epic for adventures in space -- but after pooling your nominations and taking web traffic into consideration, you voted and there is a clear winner for the year. So, what was the "Reader's Choice: Favorite Space Story of 2013"?

Read on to find out.

How do you go about finding the coldest place in the universe? Well, it helps if you have a stonking great radio telescope to scan the skies. On Oct. 23, we reported on a chilly discovery by the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile. ALMA had zeroed in on the Boomerang Nebula and gauged its temperature. Not only was the dark cloud of space dust cold, it was

the coldest object ever spotted in the Cosmos

, barely tipping the temperature scale at one Kelvin -- that's –458 degrees Fahrenheit or –272 degrees Celsius.

READ MORE: This Is The Coldest Place In The Universe

NASA's Kepler space telescope has literally transformed our understanding of planetary systems in our galaxy. Although the mission has suffered some serious setbacks this year, Kepler data continue to reveal smaller and smaller worlds circling their stars in orbits not too dissimilar to Earth's orbit around the sun. So that raises the question: How many 'habitable' worlds are out there? On Nov. 4, astronomers announced their answer:

10 billion

. Yes, there are likely 10 billion habitable exoplanets in the Milky Way.

READ MORE: Galaxy Hosts 10 Billion 'Habitable' Earth-Size Worlds

Oh Comet ISON, what the heck happened? In September 2012, Comet ISON was discovered by Russian astronomers and it was quickly revered as the "Comet of the Century." It was a virgin comet, fresh from the Oort Cloud, and it was destined to barrel past the sun to become one of the brightest objects in the sky. The world rallied behind the comet. Daily comet health updates read like war reports. The media cheered ISON on. As it got closer and closer to the sun everything was looking good! The comet was holding it together! It was going to make it! Until... it didn't. The Thanksgiving Day roast proved to be too much for this famous comet. Although there were signs that ISON's nucleus survived the encounter, the sun's extreme heat and tidal shear likely ripped it to shreds. This cosmic story may not have had a a happy ending, but ISON was no turkey; it was mainstream news for months, proving that mankind's fascination with astronomy is alive and well.

READ MORE: ISON's Ghost: 'Comet of the Century' is Now Ex-Comet

On Dec. 14, China became only the third nation ever to softly land a robot on the moon, a feat that hasn't been achieved since the Soviet Luna 24 sample return mission in 1976. The mission, Chang'e 3, lowered its six-wheeled rover, "Yutu" ("Jade Rabbit"), to the lunar surface, where it's currently taking a spin in the lunar regolith. Jade Rabbit expected to carry out science for at least 3 months.

READ MORE: China's Rover Rolls! Yutu Begins Moon Mission

Few worlds inspire the imagination quite like Europa, one of Jupiter's largest moons. The icy crust protects a sub-surface ocean of liquid water, heated from the inside by tidal interactions with the gas giant. Spectroscopic observations of Europa's ice reveal a dynamic interplay between the ocean and surface, leading to the theory that nutrients and oxygen can be cycled down below. All these factors have led astrobiologists to call for a mission to the moon; a mission that could reveal a Europan biosphere -- potentially hosting

complex organisms

. Now, in new observations by the Hubble Space Telescope, plumes of water vapor have been discovered venting into space. Wouldn't it be awesome if we could fly a spacecraft through that plume to see if any biological material has hitched a ride? Sadly, NASA's planetary sciences budget has been slashed, likely sidelining that bold idea for many years to come.

READ MORE: Hubble Discovers Water Plumes Over Europa

In a "Reader's Choice" first, I'm exercising my editorial muscle and including a multidecade story that reached its satisfying conclusion this year -- one of my favorite stories of 2013.

The hunt for the Higgs Boson, the "last" component of the Standard Model of physics, came to an end in March when physicists analyzing data from the Large Hadron Collider, near Geneva, Switzerland,

confirmed that the particle had been discovered

. This concluded the "99 percent certainty" discovery announcement of July 2012 that the particle was, without a shadow of a doubt,

the

Higgs boson. The Higgs boson is the "exchange particle" that mediates the Higgs field, endowing all matter in the universe with mass. The discovery quickly led to the original Higgs boson theoretical physicists -- Francois Englert of Belgium (pictured here, left) and Peter Higgs of the United Kingdom (right) --

being awarded the 2013 Nobel Prize for Physics

. From Higgs field theory in the 1960s, to the construction of the most complex machine humans have ever conceived (the LHC), to the boson's ultimate discovery, it's one of the biggest discoveries and most fascinating physics journeys of our time.

READ MORE: Particle 'Consistent' With Higgs Boson Discovered

The Kepler Space Telescope has discovered some weird exoplanets, worlds that are rewriting well-established planetary formation theories. However, the "Award for Weirdest" will likely go to Kepler-76b, the exoplanet that shouldn't even exist. It's small, it's rocky and it orbits its star every 8.5 hours. The location for this hot lava world has astronomers scratching their heads -- how could a world only 20 percent bigger than Earth have formed so close to a star?

READ MORE: Kepler-78b: Mystery Exoplanet Shouldn't Even Exist

As the first Canadian to command the International Space Station (ISS), astronaut Chris Hadfield had more than his fair share of responsibilities on the orbiting outpost. But that didn't stop the Ontario native from sharing his awesome experiences with Earth. For his infectious enthusiasm for bringing orbital sciences down to Earth during his five-month stay on the ISS, engaging millions in the process and starring in the first ever space music video, Discovery News selected Hadfield for the first ever "2013 DNews Person of the Year."

READ MORE: Chris Hadfield: DNews Person Of The Year

NASA's Mars rover Curiosity continues to blow us away with the incredible science it's doing in Gale Crater, gradually unraveling the mysteries of the Red Planet's habitable past one rock at a time. But on Dec. 9, mission scientists announced a groundbreaking discovery: the rover had uncovered an ancient lake bed that would have once been perfectly suited for colonies of simple, rock-eating microbes found in caves and hydrothermal vents on Earth. Although Mars roving

is taking its toll

on the robot's wheels, we can expect many more incredible science discoveries in the months and years to come.

READ MORE: Mars Rover Finds Ancient Life-Supporting Lakebed

This date -- Feb. 15, 2013 -- will be a date forever remembered as when Earth suffered a cosmic flesh wound. During the chilly morning commute in the city of Chelyabinsk, Russia, a fireball -- or "superbolide meteor" -- lit up the sky, outshining the dawn sunlight. The fireball was caused by a 12,000–13,000 ton asteroid slamming into our atmosphere at 60 times the speed of sound. The shockwaves generated by the atmospheric impact

caused 1,500 injuries (mainly from blown-out windows) and cost millions of dollars in property damage

. The Russian meteor event -- the largest in modern history and the first documented case of a large fireball explosion over a populated region -- strengthened arguments for improved asteroid impact mitigation strategies. The Chelyabinsk event proved that it's not a matter of if, it's a matter of

when

we'll get hit again.

READ MORE: Huge Fireball Explodes Over Russia

Finally,

Voyager 1 has gone interstellar!

After 35 years and 13 billion miles, scientists announced on Sept. 12 that the veteran spacecraft has left the heliosphere -- the sun's sphere of magnetic influence -- and entered interstellar space. This is the first man made spacecraft to ever achieve such a feat, officially making us a civilization that has the technology to explore the universe beyond our interplanetary front door. This achievement appears to have inspired our readers, propelling it to the #1 spot of this year's "Reader's Choice." As Voyager 1 (and her sister spaceship Voyager 2) are showing us,

space is vast

. But they also prove that accessing the space between the stars is not an impossible task. But if we are to become a true interstellar race, we'll need a faster mode of transportation before we realize our star-trekking dreams.

READ MORE: Voyager: Goodbye Solar System, Hello Interstellar Space