Arcadian Functor

occasional meanderings in physics' brave new world

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Marni D. Sheppeard

Thursday, November 06, 2008

Picoseconds I

Soon after the arxiv release of the exciting new CDF result, a phenomenological paper proposing new physics also appeared.

Using the PYTHIA Monte Carlo event generator, the authors found that a cascade of three new states (called $h_1$, $h_2$ and $h_3$) could explain the observed excess of correlated muons with high impact parameter. This cascade ends with the generation of eight $\tau$ particles from four $h_3$ states:

$h_1 \rightarrow 2 h_2 \rightarrow 4 h_3 \rightarrow 8 \tau$

The generator assumes a $p \overline{p} \rightarrow H \rightarrow 2 h_1$ process, where $H$ is the fairy field, but it is pointed out that this is for convenience only, and the actual process is a mystery. In the words of the authors: the observed pair production cross section is a few orders of magnitude larger than what is predicted if the $h_{i}$ states belonged to the Higgs sector.

The best fit to the data, which includes vertex reconstruction, results from attributing the long lifetime (about 20 picoseconds) to the $h_3$ state. The mass triplet for $(h_1,h_2, h_3)$ appears to scale as $(4,2,1)$, with $m(h_1) \simeq 15 GeV/c^2$.

Aside: See also posts by Matti Pitkanen and Carl Brannen.


Blogger Kea said...

P.S. Funnily enough, one of the authors of this paper applied for a tenured position at UC. I listed him as my preferred candidate, but I suspect that nobody took my opinion seriously. Anyway, he wasn't hired.

November 06, 2008 5:33 PM  
Blogger Matti Pitkanen said...

Dear Kea,

thank you for the link. I have had little health problems but I am trying to see whether the TGD based model for jets based on strong decay cascade of p-adically scale up tau-pions (neutral ones have masses 2,4, 8 m(tau) and charged ones 1,2,4 m(tau)in good approximation) is consistent with what is know about the opening angle for the lepton jets.


November 07, 2008 12:09 AM  
Blogger Matti Pitkanen said...


I found that the kinematics for sequential decays of p-adically scaled up pions implies the jet property correctly also at quantitative level.

If it is assumed that the decays of neutral pion can occur to on mass shell pions (this is absolutely essential) at longer p-adic length scale, the very small phase space available implies the jet property.

The cone angle is predicted to be 45 degrees for for first secondary muons and 26.6 degrees for second secondary muon. The measured opening angle is 38.6 degrees.

TGD predictions are consistent with all basic quantitative and qualitative aspects of the lepton jets according to CDF collaboration that I know now: masses; lifetime 20*10^(-12) seconds of the longest lived new particle (there are actually several them); opening angle of jets. The model involves only known masses and coupling constants. p-Adic fractality and colored leptons are basic predictions of TGD.

The rate for the production tau-pion with p-adic scale k=103 is yet to be calculated: this requires only the use of already existing formulas and some numerical integration.

For the detailed argument see my blog.

November 07, 2008 3:56 AM  

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