Results from EPS-HEP 2011
Results from the EPS-HEP 2011 conference that began today are starting to appear. These include the first results making use of most of the 2011 LHC run data. This is a factor of 30 or so more data than that from the 2010 run, which was the source of almost all previous results released by the LHC experiments. Some of the news so far:
ATLAS pretty much says here that there are no squarks or gluinos below 1 TeV (see page 9). Comparing to analyses of the regions considered mostly likely (see for example here, figure 7) pre-LHC, significantly more than half of the region in which supersymmetry was supposed to appear is now ruled out. Another factor of 10 or so in data should come in during the rest of the 2011/2012 run, which should allow limits to be pushed a bit higher. At this point, it looks like SUSY is on its way out. It will be interesting to see if die-hards insist that the factor of 2 in energy at the next (starting in 2014-5) run will make a difference.
For results relevant to strings, black holes, extra dimensions, split supersymmetry, and other exotica, CMS has them appearing here, for ATLAS they’re here. No such objects are being seen, with limits being pushed up dramatically from those coming from the 2010 data. Again, it’s going to be very hard to argue that there’s a significant probability that such things will be seen in the rest of this run, or even later ones at full energy.
CDF results available here say no Higgs between 156 and 175 GeV, D0 exclusion (here) looks like it covers about 160-170 GeV. Fermilab has issued a press release about this, advertising the release of the combined numbers at a July 27 talk. This should also include low mass searches which might provide exclusion above the 114 GeV LEP limit. The press release mentions a “most likely” range of 114-137 GeV for the Higgs mass, and links to earlier Tevatron exclusion limits, but I suspect the 137 number comes from a different source, not a Tevatron direct search result.
CMS and ATLAS results on the Higgs are to be announced tomorrow afternoon (an early version of the CMS results leaked here). A combination of results from the two camps will be done after the conference, planned to be announced at Lepton Photon 2011 in late August, although a rough guess as to what that will look like should be available just from seeing the two independent results.
Philip Gibbs is keeping a close eye on this at viXra log.
Update: Tommaso Dorigo has some more news here: CMS is not seeing the SM violating forward-backward top pair production asymmetry seen at the Tevatron (more about it here).
Update: ATLAS results on the Higgs are 95% exclusion 155-190 GeV and 295-450 GeV. They see a 2.8 sigma excess of events in the 120-140 GeV range.
Update: I just noticed that Matt Strassler now has a blog and is blogging from Grenoble.
Update: Matt Strassler reports from the CMS Higgs combination talk that they exclude 145-480 GeV at the 90% confidence level. Some excess 120-145 GeV, smaller than ATLAS.
So, in summary, it looks like the LHC + Tevatron have pretty much excluded a high mass Higgs, narrowed the possible mass range down to 114-150 GeV or so. No evidence at all of anything but the SM. The big story of the next few months will be to watch and see if a Higgs signal emerges in the last non-excluded region. Or not….
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