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Dear Colleagues,

We have been thinking about ways to explain the interest in the continuation of the experimental
program in Energy Frontier.   We propose the following idea, which we ask you to address in
the studies of your working groups and in your final write-ups.   We will discuss this idea further
at the phone meeting tomorrow.

We tend to think in terms of eliminating regions where new physics might be. We wonder if we 
might also talk about a few test-case discoveries. We anticipate that this might be a healthy way 
for groups to talk to one another, but also in the end a useful way to explain how our detectors are 
capable of following up realistic leads that might point to new physics. It also would be a useful 
story-telling device for our writeup and eventual public and agency consumption. We also thought 
it might be fun.

We have made a list of anomalies below which are gentle extrapolations from current hints in the 
data, or signals that are reasonable and "right around the corner" when 14TeV running begins.  There 
are 9 cases in all. We have tried to include at least one specific to each working group, and also to 
include anomalies that are actually attracting interest now (at an unconvincing level of significance) 
and could become established later in the decade.

For each of these anomalies, we would like you to discuss

1. What would an experiment need to do to be convincing?

How will we establish that this effect indeed exists and is a violation of the Standard Model? What are
the dangerous systematics? What tests would a group do?  This will
      be primarily the task of the specific working group under which the anomalies are listed.  Note that
         for #3 under New Phenomena this is really the task of the Cosmic Frontier.

2. What could it be?

What kinds of new physics models lead to this particular deviation from the Standard Model?  For this
     we would like you to look at all of the anomalies, not just those in your working group.  In the
      area of your working group, what future experimental program -- over the next 20 years -- would be
         required to follow up on and explain the discovery?

3. What next?

Note that any of these discoveries would lead to the need for future research. What would the most 
fruitful next directions? Within, and outside of the EF?


We hope that this task will not be burdensome and will add some needed optimism to your assessments. 
We plan to talk more about this at the Brookhaven meeting.

Thank you very much,


Chip Brock and Michael Peskin


On Mar 17, 2013, at 9:19 PM, "Peskin, Michael E." <[log in to unmask]<mailto:[log in to unmask]>> wrote:




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Electroweak Challenges (2)
----------------------

1. W mass
With the inclusion of the full Tevatron and future LHC data sets, the W mass is measured to be     mW = 80.400 pm 10 MeV .

https://indico.in2p3.fr/getFile.py/access?contribId=41&sessionId=8&resId=0&materialId=slides&confId=7411

2. WW production cross section
sig(WW) production determined to be 1.2 pm 0.05 x sig(SM)

https://indico.in2p3.fr/getFile.py/access?contribId=43&sessionId=10&resId=0&materialId=slides&confId=7411

Top Challenges (1)
--------------

1. An enhancement is observed at M(ttbar) = 1.8 TeV in the semileptonic channel.

https://indico.in2p3.fr/getFile.py/access?contribId=31&sessionId=8&resId=0&materialId=slides&confId=7411

Higgs Challenges (1)
----------------

1.  The overall rate for  gg -> h -> gamma gamma at the LHC is seen at a value sigmaxBR/ Standard Model =  2.0 pm 0.2

https://indico.in2p3.fr/getFile.py/access?contribId=45&sessionId=6&resId=0&materialId=slides&confId=7411


QCD Challenges (1)
--------------

1. An enhancement in the dijet invariant mass observed above M(jj) > 6000 GeV

NP Challenges (3)
--------------

1. A narrow enhancement in dilepton invariant mass is found at 3 TeV, consitent with the signal of a sequential Z' of mass 3 TeV.

2. A peak appears in the dilepton invariant mass is found at 2.5 TeV leading to a cross section which is roughly 5% of a sequential Z’ cross section at that mass.

https://indico.in2p3.fr/getFile.py/access?contribId=52&sessionId=8&resId=0&materialId=slides&confId=7411

3. The feature at about 130 GeV in the Fermi GST gamma ray spectrum near the galactic center is confirmed to be a narrow line with 5 sigma significance.

https://indico.fnal.gov/contributionDisplay.py?sessionId=13&contribId=105&confId=6199


Flavor Challenges (1)
-----------------

1. The LHC experiments at 14 TeV discover a  5 sigma excess of trileptons, with no discernable structure and no obvious correlation with missing energy or
Z production.   The signals, including hadronic tau events, are consistent with  (e, mu, tau)  production.

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