
What to Expect from the L.H.C. Reboot - jonbaer
http://www.newyorker.com/tech/elements/what-to-expect-from-the-rebooted-large-hadron-collider
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sgt101
The article claims that 1000's of Higg's events were detected. My belief is
that CMS saw 20 ish events and Atlas about 200. Is there anyone who actually
_knows_?

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mattheww
This is not a very straight-forward question to answer. The short answer is
that both CMS and ATLAS detected a couple thousand Higgs events.

The long answer depends on your definition of detected. As you probably know,
the Higgs decays into many different combinations of particles. In some of
these cases, we have very little chance of determining whether there was a
Higgs in the event. In fact, only in H(iggs) -> ZZ -> 4l(eptons), do we stand
a reasonably good chance of saying whether a specific event contains the
Higgs. In this channel, CMS and ATLAS both observed ~20 events.

The next two most sensitive channels are H->WW->2l+2nu (neutrino) and
H->2photon. In the most Higgs-enriched regions that have been constructed, the
contribution from Higgs is ~10% in H->WW->2l+2nu and ~20% in H->2photon. So in
these channels, we have very little chance to say whether a specific event
contained a Higgs, but if we look at all the events, we see features that
wouldn't be present if there weren't any Higgs bosons. The contributions from
Higgs in these channels are a few hundred events in CMS and ATLAS.

Then there are even less sensitive channels, which means we have even less
chance to say whether a specific event contains a Higgs. CMS and ATLAS
probably detected a few hundred to a thousand or so events each in these
channels.

