Monday, 6 May 2013

Pheno 2013 Live Blog

I am abanding this live blog, as it is impossible on this total piece of shit tablet.  I leave what is below for posterity.
I'm unfortunately on a tablet right now, which will be a problem.

Talk 1: Cristina Blino: SM Results from LHC

We start with a review of theSM results from the LHC.

Actually, we start with some bad feedback, but that's been fixed now.

Usual stuff, namely illustrating the challenge that the experimentalists must face with pile up, for example.  It convinces me; I think the whole thing is black magic.

Standard Model  background to the interesting stuff, but it describes the data so qell over so many orders of magnitude that it is really a bit too good.

Writng on this tablet is awful.

Despite the LHC being a hadronic machine, and thus not clean, the high luminosity has already let to some impressive precision, especially for the gauge bosons (leptonic modes).

Forward-Backward asymmetry in lepton pair production.  Any asymmetry at LHC is tricky, due to symmetric initial state.  Measured, agrees with lepton machines; relevant for future studies of ttbar asymmetry.

W-photon production slightly in excess of theory; look into this later.

Triple gauge couplings are a common result; I don't actually know what models would show up there.  Limits improve, of course.

One problem with some of these plots for diboson production, is that it's not clear if theoretical errors are shown.  Some of jh the measurements are slightly off the theory lines, but I expect there's still one-sigma agreement.

Top Quark:
  • One top pair per second.
  • Cross Section already systematics-dominated.
  • Ah theory errors shown here.  Even the small difference from 7 to 8 TeV cross section can be resolved.
  • Single top; errors here still relatively large.
First talk runs long.  Not an auspicious opening.

In summary, we have a terrifying array of data, with precision and agreement with theory that is both impressive and intimidating.  The most interesting result I saw was the W-gamma measurement, which probably isn't significant but right now we can't be too picky.

Talk 2: K.K. Gan: BSM searches at LHC

The obvious folow-up to the previous talk.

I really fucking hate trying to write on this tablet.  I'm spending far tpo much time fighting the fucking interface.  And forget correcting typos, that would imply being able to move the fucking cursor, and clearly that's an unreasonable functionality to expect.

SUSY: standard motivations.
  • Stop searches; leptons plus MET.
  • The degenerate slices still exist.
  • Coverage away from that is pretty good.  Exclusion up to order 400 GeV.
It's notable how the results immediately fpocus on stops.  No time wasted on traditional searches.  That's  the time we live in.
  • Heavy stop pairs, decaying to stop plus Z.  Gah, missed the limits there.
  • Gluino pair production, decaying to stops.
  • The usual TeV exclusion.
  • Two things occur to me.  How much wiggle room remains in the degenerate regimes, and can such a specyrum even arise in a top-down manner?
  • The pMSSM papers can probably answer that first question.
  • Squark and sbottom searches slightly underperformed expectations.  Interesting.
  • Electroweak production; chargino-neutralino production.  Three leptons, clean to compensate low cross section.
  • Limits on LSP up to 200 GeV for appropriate spectrum.  Chargino to 600 GeV for same assumptions.
  • Just lost a minute trying to make this thing work.  Fuck.
In summary: SUSY continues to look dead.  Lecture says don't worry; we can never exclude SUSY,so we have plenty of job security!

  • Exotica: Z primes?  Really, not very exotoc.  Of course, eady for experimentalists thanks to leptons.

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