80beats: Are There 5 Higgs Bosons?

[bystander]

Fermilab Particle Physicists Wonder: Are There 5 Higgs Bosons?
Discover Blogs | 80beats | 15 June 2010

If the Higgs boson is the “God Particle,” then some particle physicists just turned polytheistic. To explain a recent experiment, they wonder if five Higgs bosons give our universe mass instead of one.

Last month, we discussed a curious experiment at the Tevatron particle accelerator at Fermilab near Chicago. Colliding protons and antiprotons, the Tevratron’s DZero group found more matter than antimatter.

This agrees well with common sense–if the Big Bang had really churned out equal amounts of matter and antimatter, the particles would have annihilated each other, and we wouldn’t be here. Unfortunately, the physics for this matter favoritism doesn’t make sense.

For one, it requires some fudging to fit the Standard Model, the organizing theory for particle physics. This might seem sad since we were so close to finishing the Standard Model up, with the Higgs filling the last cage in physicists’ particle zoo:

For those who believe the Standard Model is nearly complete, the discovery of the Higgs boson–a theoretical particle that imparts mass to all the other particles–would close out the final chapter. But for others who think that undiscovered physics properties exist–so-called new physics–a sequel to the Standard Model is needed. [Symmetry]

What would a sequel to the Standard Model look like? The Higgs Strikes Back might include five Higgses, particle physicists at the DZero group speculate: all with the same mass, three uncharged, one with a positive charge, and one with a negative charge. Theoretical physicists have already dreamt up this possibility, calling it the “two-Higgs doublet model.”

As explained in a BBC report, this version of the Standard Model would leave most of the original theory intact, a feat in a system that doesn’t have much wiggle room:

“In models with an extra Higgs doublet, it’s easy to have large new physics effects like this DZero result,” [Fermilab's Adam Martin] explained. “What’s difficult is to have those large effects without damaging anything else that we have already measured.” Dr Martin explained that there were other possible interpretations for the DZero result. But he added: “The Standard Model fits just about every test we’ve thrown at it. To fit in a new effect in one particular place is not easy.” [BBC]

Given, that the Fermilab found this antimatter vs matter result, we might wonder if they too will find these fascinating, elusive Higgs boson particles, perhaps stepping on the toes of their higher-energy rival, the Large Hadron Collider.

It may comes down to how much mass these particles have (currently unknown). If the Higgs are Greek god particles, Fermilab is better suited to detect a more delicate Athena Higgs, while LHC might more easily find a fatter Silenus particle.

Related content:
Discoblog: World Science Festival: What if Physicists Don’t Find the Higgs Boson?
80beats: In the Universe’s Decisive Battle, Why Did Matter Prevail Over Antimatter?
80beats: LHC Beam Zooms Past 1 Trillion Electron Volts, Sets World Record
80beats: In 1 Week, the LHC Will Try to Earn the Title, “Big Bang Machine”
Discoblog: I Swear: Subatomic Particles Are Singing to Me!

[bystander]

Study finds there may be multiple 'God particles'
PhysOrg | General Physics | 16 June 2010

Recent research in the US suggests there may be five versions of the theorized Higgs boson.

The Higgs was dubbed the "God particle" by Nobel laureate Leon Lederman because its discovery could unify our understanding of the universe and help us “know the mind of God”.

The Higgs is extremely important to the accepted theory of physics, known as the “Standard Model”, which was developed in the 1970s to incorporate everything known at the time about interactions between sub-atomic particles. The Higgs boson is thought to be the sub-atomic particle that mediates the force through which all other sub-atomic particles acquire their mass.

Scientists have been trying for five decades to detect the Higgs boson, but have so far failed. Now theoretical physicist Adam Martin and colleagues at the Fermilab’s Tevatron particle accelerator near Chicago in Illinois in the US have analyzed results from the DZero experiment and suggest there may be multiple versions of the Higgs boson.

CP violation in B_s mixing from heavy Higgs exchange

• arXiv.org > hep-ph > arXiv:1005.4238 > 23 May 2010

[The Code]

If at some point, all the universe was smaller than a nucleus, I would say, the elusive mass particle, could be as small as the universe is big.

[bystander]

The Higgs Boson May Have 'Five Faces'
Discovery News | 21 June 2010

Fermilab's Tevatron accelerator has been making some serious waves the last few months. Back in May, I wrote about the latest results from the D-Zero collaboration, co-discovers of the top quark in the 1990s. The D-Zero scientists analyzed data from a bunch of proton-anti-proton collisions and found a 1 percent asymmetry in the number of muons produced compared to anti-muons, hinting at "a new particle not predicted by the Standard Model" -- colorfully dubbed "the toe of god" by Fermilab scientist Joe Lykken.

[youtube]http://www.youtube.com/watch?v=1_HrQVhg ... r_embedded[/youtube]

And now the team is back with even more intriguing results to announce from their subsequent analysis, published on arVix. See, the Standard Model doesn't fully explain why this asymmetry between matter and antimatter should exist. Yet, as Fermilab scientist Adam Martin pointed out to BBC News, "What's difficult is to have those large effects without damaging anything else we've already measured. The Standard Model fits just about every test we've thrown at it. To fit in a new effect in one particular place is not easy."

Nonetheless, theoretical physicists are pondering possible alternate explanations that would keep much of the Standard Model's framework intact while still offering a potential explanation of this latest experimental evidence. And they've come up with a doozy: maybe there isn't just one Higgs boson (the as-yet-undiscovered subatomic particle believed to impart mass); maybe, instead, there are five different versions, with similar masses but different electric charges.

Yes, it's not enough that the Standard Model already has so many types of subatomic particles that it's impossible to keep them all straight without a handy cheat sheet. Never mind that the theory of supersymmetry would add countless more particles to the mix. Now we have to contend with five -- count 'em, five! -- Higgs bosons: three with a neutral charge and one each with a negative and positive charge, known as the "two-Higgs doublet model." Apparently this would account for the latest D-Zero results.