Comments on: CDF Ghost Muons

By: New Physics?

New Physics? — Mon, 10 Nov 2008 07:11:07 +0000

[...] Physicist at the Fermilab Collider Detector (CDF) report multi-moun events. Until now, nobody knows, why CDF detected these ghost mouns – “it’s either an unaccounted-for background or it’s new physics”, as John a physicist wrote in his weblog. [...]

By: Hello world! « How the World Works

Hello world! « How the World Works — Mon, 10 Nov 2008 01:40:08 +0000

[...] Here is a basic explanation of the results:CDF Ghost Muons [...]

By: Chris Austin

Chris Austin — Sat, 08 Nov 2008 20:15:50 +0000

Hi John,

Thanks for the helpful explanations. What is your opinion on Bob McElrath’s suggestion above that the explanation will turn out to be unknown B-hadrons with anomalously long lifetimes, and do you have the necessary raw data that would be required to disentangle the contributions of different unknown B-hadrons, and analyse exclusive final states as he suggests?

Best regards,
Chris

By: Maynard Handley

Maynard Handley — Thu, 06 Nov 2008 23:04:53 +0000

“Due to a subtlety in the weak interaction that we need not explore here, a b quark (or more properly speaking a B hadron) flying along can change spontaneously into its own antiparticle.”

Can you clarify this statement?

Would you have a problem with the claim that the essential difference between a particle and an antiparticle is the sign of the rate of change with time. (So for an energy eigenstate, this rate of change, ie the frequency, is either positive or negative, giving us particle or anti-particle)? Or would you say such a characterization in fundamentally misguided?

If we assume this characterization is correct, is the point then that a B meson
- is not in fact an energy eigenstate AND
- unlike most “simple” non-eigenstates. if we were to plot “phase” (in some vague sense) against time, rather than seeing some variety of sinusoid like a beat pattern, the plot is best done showing a complex point against time, with the point moving first clockwise, then slowing down, stopping, moving anti-clockwise, then the whole thing reversing?

By: Sili

Sili — Mon, 03 Nov 2008 21:40:06 +0000

What is it they say? “New physics isn’t hailed with a ‘Heureka!”, but by someone going ‘Huh. That’s odd.’”

By: News from the CDF and PAMELA experiments « Theorema Egregium

News from the CDF and PAMELA experiments « Theorema Egregium — Mon, 03 Nov 2008 20:42:02 +0000

[...] See a new post over at Cosmic Variance by John Conway, another CDF [...]

By: a quantum diaries survivor

a quantum diaries survivor — Mon, 03 Nov 2008 20:09:39 +0000

Hi optimistic,

a third of the collaboration objected about the publication process, the paper content, the personality of the main author, and the day of the week of the release.

The thing is, the main author is a brilliant physicist, with zero PR skills. He alienated most of his colleagues during 25 years of work in CDF. This explains some of the reaction to his analysis.

The analysis itself is complicated, as John states from the outset above. It entails loosening the criteria of identification of muon candidates, which have a good reason to be there. But still, we need to understand our muon candidates even with loose cuts. This leads us to this sample, which is very hard to reconcile with SM sources. Many in CDF thought that we should keep to ourself our dirty laundry, others thought we should release that information.

Cheers,
.

By: Lawrence B. Crowell

Lawrence B. Crowell — Mon, 03 Nov 2008 15:41:30 +0000

The paper by Arkani-Hamed & Weiner makes these suggestions in figure 2. If I am right these ideas of “gauge-Moose” are a sort of twisted SUSY with a chain of gauge fields on the winding loop around some space. I’d have to read this paper more fully to get a better idea of where this is heading. Yet figure 2 does point to electrons as the lepton jet. One might expect this do dominate over muon production.

This paper along with Sean’s recent paper and with other conjectures and hypotheses on DM do hint that DM might in some way reflect a weakly interacting ghost world that couples to our “gauge world” by gravity and very weakly by other interactions.

Lawrence B. Crowell

By: Neal Weiner

Neal Weiner — Mon, 03 Nov 2008 13:23:58 +0000

Hi Bob
Our statement about lepton jets wasn’t just about production of the vector itself, because typical decays through the G_dark sector don’t go right to the vector, but proceed through some intermediate states, hence the n>=2 rather than n=2 definition of the lepton jets…

That said, getting this rate would be a challenge!

Neal

By: Bob McElrath

Bob McElrath — Mon, 03 Nov 2008 08:52:02 +0000

The model by Arkani-Hamed and Weiner absolutely cannot be responsible for these muons. Their light boson would be extremely narrow, and would show up in an opposite sign dilepton plot quite clearly (just as the J/Psi does in at least one of the plots).

I think the answer is clear: some currently unknown B-baryon or B-meson (or maybe several) has an anomalously large lifetime. The lifetime is only a factor of 10 over the B meson, so a B-hadron is an obvious choice. These states are not in Pythia and will not show up in your MC. Most of the B-baryons are unknown. These things definitely are in the sample, the only question is whether there is anything in there that’s not B-hadrons, and why does the state have an anomalously long lifetime.

A more specific analysis need to be done looking at exclusive final states to identify the B-hadrons. The paper has a lot of plots which clearly mix a lot of different signals coming from different mesons, so it’s extremely hard to interpret them. The only thing that’s clear is that there is no new state with a 2-body dimuon decay (which B-decays aren’t anyway). But discovering a pile of B-hadrons not in the PDG is exciting!