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Comment: Re:I got a butt chewing for giving my daughter hon (Score 1) 239

by Pro-feet (#49121605) Attached to: Study: Peanut Consumption In Infancy Helps Prevent Peanut Allergy

This has nothing to do with allergies. You don't feed babies honey to avoid the very rare cases where it actually causes immediate problems. After a year it is perfectly fine.
It's like some of the things that are excluded while being pregnant (cats, game meat,...), just a precaution for the possible rare, but severe consequences of an unwanted contamination.

Comment: Re:Actually 13/8 times the energy (Score 1) 89

by Pro-feet (#49086555) Attached to: Scientists To Hunt For Supersymmetric Particle In LHC

The gluino plays a similar naturalness role as the stop, at 2-loop level. Now you are aware, though I made that point in my previous post too.

Just beyond the limits is not an arbitrary choice. Given our current limits already, naturalness points to these masses being as low as possible.

Comment: Re:Actually 13/8 times the energy (Score 1) 89

by Pro-feet (#49082473) Attached to: Scientists To Hunt For Supersymmetric Particle In LHC

For the same reasons the stop is expected light (naturalness, i.e. SUSY as a solution to the hierarchy problem), also the gluino is expected light. What is light? Some put it at 400GeV for the stop, and 1.5 TeV for the gluino. But it's a bit of a subjective point. So if you like natural SUSY, you expect the gluino to be around the corner, and the stop to be within reach, but probably decaying softly and therefore having escaped detection so far. How likely is such a scenario? There is no good metrci for the likelihood of models. Therefore I prefer to look at it experimentally, i.e. wrt our current limits. If the gluino and stop are just beyond our current limits, then, according to my previous posts (which apparenntly completely missed the point...) the gluino will jump in our face, while the stop will take more time.

Comment: Re:Actually 13/8 times the energy (Score 1) 89

by Pro-feet (#49075747) Attached to: Scientists To Hunt For Supersymmetric Particle In LHC

I referred to the current limits (~1.2TeV for gluino versus 700GeV for stop), which is more or less corresponding to a couple of events on a small background - for both gluino and stop searches at their high-mass extremes.
Production probability (cross section) plot for 8TeV can be seen here:
http://inspirehep.net/record/1...
Couldn't find a 13TeV version quickly; but the trends are the same: much higher probability for gluino paris (~g~g in red) than for stop pairs (blue curve).
Now, when we move from 8TeV to 13TeV, for a gluino just at the limit, the production probability goes up much more than for a stop at its own somewhat lower limit.
So I'm not assuming same mass, I'm assuming a heavier gluino actually.
Of course, for a 5TeV gluino, no chance; but the same goes for a 2TeV stop - production rate too low.

Comment: Re:Actually 13/8 times the energy (Score 1) 89

by Pro-feet (#49069187) Attached to: Scientists To Hunt For Supersymmetric Particle In LHC

Yes, the stop (and sbottom) squark is a prime target too.
But it will come again a little later than the gluino. The reason is that we have excluded the gluino in most scenarios already wel beyond 1.2TeV, while the stop squark is unlimited above ~700GeV (and that's assuming ideal decays).
Now, with the increase in energy, the heavier is the particle, the higher the increase in production probability. This is visualised in the following (M_X being the "mass" of the produced system, in this case twice the gluino or stop mass, since they come in paris; and the solid line being the most relevant here for strong production):
http://www.hep.ph.ic.ac.uk/~ws...
For a gluino at the limit of what we could exclude until now, a ~ fifteenfold increase in production probability is expected, while for stops it will be more a factor 6 or 7.
A final argument why stops take a little longer is that the main backgrounds (top quark pairs, mainly) are looking quite similar even in the easier decay modes, while many of the possible gluino decays lead to signals that have a tiny background (like four-top final states).

Comment: Re:Actually 13/8 times the energy (Score 2) 89

by Pro-feet (#49061591) Attached to: Scientists To Hunt For Supersymmetric Particle In LHC

True.
But, if we are going to discover a SUSY particle in the first months after turning on, it is indeed very likely to be the gluino. Just because the probability of creating it, if it is within kinematical reach, will be large, compared to many other SUSY particles. All weakly produced particles will take more data to get hold of because they are rarer. In addition, in most models, the gluino decays give rise to spectacular collisions, that are relatively easy to distinnguish from known backgrounds.

Comment: Re:proton decay? (Score 1) 89

by Pro-feet (#49061581) Attached to: Scientists To Hunt For Supersymmetric Particle In LHC

You only need one extra symmetry (so-called R parity) to protext the proton from decay. Such a symmetry is not far-fetched, and arises in some GUT models even dynamically. Imposing this R parity yields also automatically a stable lightest supersymmetric particle, and it turns out that that can be a really plausible dark-matter candidate. This said, studies also go on about models where this R parity is not conserved, still keeping the proton's lifetime within the stringent experimental bounds.

Comment: Re:Wow they might find a new particle (or not) (Score 3, Interesting) 89

by Pro-feet (#49061551) Attached to: Scientists To Hunt For Supersymmetric Particle In LHC

A 126 GeV Higgs boson as we (also CMS did, btw) have observed it, and studied its properties in detail, is no problem to be accomodated in even the minimal versions of supersymmetry. What makes you say it was not expected at that mass? It's on the high side, but the higher the mass, the more that Higgs boson with or without supersymmetry would look the same in our detectors...

Comment: OPERA did not claim FTL neutrinos (Score 1) 142

by Pro-feet (#48681021) Attached to: New Paper Claims Neutrino Is Likely a Faster-Than-Light Particle

What the OPERA collaboration claimed was that they had an anomaly in their data, which led to a possible interpretation of nneutrinos travelling faster-than-light. Since they found that a very extrordinary claim, they knew they needed extrordinary evidence, and after a few months of searching within, they opened up to the scientific community to help find their mistake, if any. They were very scientific about the whole thing, and didn't at any point claim "hey look here, we found neutrinos to go faster than lightspeed!".

In summary, TFS contains crap on the part I know about, so I'm not inclined to go read TFA... I'll hear it from a more reliable source if it turns out to be anything important.

Comment: The nobel was for prediction, not discovery (Score 3, Insightful) 137

by Pro-feet (#48346263) Attached to: CERN May Not Have Discovered Higgs Boson After All

TFSFS, i.e. The First sentence of TFS, is a load of crap. Physicists Peter Higgs and Francois Englert won the Nobel Prize for *predicting* the Higgs Boson, *not* for discovering it!

And the rest of the summary doesn't make me a bit interested in reading TFA either. There's been Higgs imposter models out there from before the discovery was made. And sure they have their merit. But as long as we have no new physics observed, the Standard Model covers it just fine.

"It's when they say 2 + 2 = 5 that I begin to argue." -- Eric Pepke

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