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Quaero
Bruce KnutesonBerkeley/Chicago
An automatic model-tester
A new way to publish HEP data
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Motivation
How do new physics searches usually work in this field?• Theorist writes down a model• Six months later an experimentalist decides it is worth checking• Two years later her graduate student finishes the analysis• Six months after that the publication comes out
Is it possible to this in 3 hours, rather than 3 years?
An automatic model-tester
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Where do we spend most time during an analysis?1. Understanding backgrounds to data2. Generating signal Monte Carlo and associated bookkeeping3. Optimizing cuts and setting limits
Not a whole lot we can do about #1 . . .
But can we offload #2, and automate #3?
MotivationAn automatic model-tester
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Quaero final statesAn automatic model-tester
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The details of the Quaero algorithm have been presented in New Phenomena and Run I meetings
The basic idea is quite simple:
The algorithmAn automatic model-tester
1. Construct a background estimate
2. Construct a signal estimate
4. Choose Dcut to optimize an expected 95% limit
3. Define D=p(s)/[p(s)+p(b)]
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But does it work?
ExamplesAn automatic model-tester
Example analyses performed:
WW eET
ZZ eejj
h WW eETjj(nj)
h ZZ eejj
tt eEtjj
tt eETjjjj
Z’ tt eETjjjj
LQLQ eejjDetails available in draft Quaero PRL
Results all appear reasonable, with no fine-tuning
(w/ Greg Landsberg)
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An automatic model-tester
A new way to publish HEP data
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Now that Run I is winding down, how can we preserve our data in an accessible form?
• Our data are “context-specific”(You need to understand an awful lot about it
in order to do anything with it)
Is there a way that we can make our data easily available, both to ourselves and people outside
DØ?
MotivationA new way to publish HEP data
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Astrophysicists appear to have solved this problem
High energy physicists so far have not, despite serious attempts (e.g. at LEP)
Perhaps DØ has hit upon a solution?
MotivationA new way to publish HEP data
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Advantages include:# of models outnumbers # of us by lots
Put theorists to work
Perhaps we missed something?Never hurts to have another pair of eyes
Increase number of DØ citationsReferences to the papers describing the data
Education / outreach via QuarkNetSome additional work (niftier interface), but great PR
potential
Frees us up to focus on Run IIBut lets us make the most of Run I
Facilitates communication with theoristsShould help bridge the theory/experimental gap
DØ would be leading HEP in making its data accessible
Other experiments have tried (and failed) to solve this problem
Allows us to beat any CDF analysis by at least a year
Quaero has the answer in a matter of hours.
PossibilitiesA new way to publish HEP data
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There are a number of ways Quaero could be implemented
PolicyA new way to publish HEP data
“Put the data out there”Make data available to all with no internal review
Make data available with limited scope and internal review
Restrict those who are allowed to use QuaeroReview all Quaero results before releasing them
Don’tKeep Quaero as an internal tool
Make data available with general scope and more limited internal review
many variations on these themes
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Representative comments/concerns from collaborators(Opinions were uniformly thoughtful and reasoned —
thanks to many for valuable discussions)
DØ worked incredibly hard for Run I data. Do we really want to “give it away”?
What responsibility would DØ be shouldering? What if some nut claims an unfounded discovery?
Does this set a dangerous precedent for Run II? Would this have a detrimental effect somehow on exp
HEP?Does DØ have the resources to conduct an internal review of all Quaero results?
Who would do it? What would the rules be?Does making Quaero results available only after internal review seem slimy and unforthcoming?
PolicyA new way to publish HEP data
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My view/proposal:
We have a real opportunity here
There are legitimate concerns about making DØ data publicThis has not been done before
These concerns can be addressed (I think)
I began this effort believing that an internal review of Quaero results was necessary
Does DØ have resources to commit to this effort? No.Would it be cleaner to provide results directly? Yes.What if there are bugs in Quaero? Make sure there aren’t.
I currently feel that the cleanest approach (with greatest potential advantages) is to “put the data out there”
PolicyA new way to publish HEP data
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The present plan:
EB 139 is reviewing the accuracy of the Quaero method and example analysesQuaero was made available for general New Phenomena group testing beginning December 2000 All are welcome to test Quaero beginning today.http://www-d0.fnal.gov/~knuteson/d0_private/quaero/(From Feb 15th onward Quaero will also generate signal for you.)
Comments and suggestions are actively solicited
PRL draft existsDescribes Quaero method, data, and results of examples
Hope to simultaneously publish in PRL and release Quaero to the HEP community
PolicyA new way to publish HEP data
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Quaero
An automatic model-tester
A new way to publish HEP data?
Conclusions
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