1. Bard An algorithmic solution to the LHC interpretation problem
Bruce Knuteson
MIT
Pheno May 2006

3. These data are not available to you
HERA DESY Hamburg, Germany
These data are not available to you
e p
300 GeV
1992 -
2000
2002 -
2006

4. These data are not available to you
LEP II CERN Geneva, Switzerland
These data are not available to you
e+ e-
200 GeV
1996 -
2000

5. These data are not available to you
Tevatron Run I Fermilab Chicago
These data are not available to you
p p
1800 GeV
1992 -
1996

6. These data are not available to you
Tevatron Run II Fermilab Chicago
These data are not available to you
p p
1960 GeV
2001 -
2009

7. These data will not be available to you
LHC CERN Geneva, Switzerland
These data will not be available to you
p p
14000 GeV
2008 -

8. 8 9 9 8 8 9 10 7 ½ ½ ½ Detector effect Statistical fluctuation
Poor prediction
Compelling interpretation

9. Standard Model
Data

10. Bard
model construction
“weave a story”

11. hep-ph/

12. 105 d 10
(1 sec)

13. If we see a signal, how do we interpret it in terms of the underlying physical theory?

15. Generic new particles spin 0, ½, 1 electric charge n/3
color singlet, triplet or octet

16. Generic new vertices

17. Bard stories
|g|2 m1 m2 m3

18. Bard output
Ordered list of stories, together with best fit parameters and errors
Analysis details are available from links

20. Quaero status currently no competition DØ Run I H1 L3 Aleph CDF Run II
PRL H1 L3
Aleph
technically complete, not yet published
CDF Run II
under development
Run I data
discrepancy finding

21. Sleuth How do we find the excess? quasi model independent
New physics will appear:
1. Predominantly in one exclusive final state
2. At large ΣpT
3. As an excess

22. Sleuth / General Search status
currently no competition
DØ Run I
Phys.Rev.D 62:092004,2000
Phys.Rev.D 64:012004,2001
Phys.Rev.Lett.86:3712,2001
H1 Run I
Phys.Lett.B 602:14-30,2004
P=0.03

23. Vista How do we understand the data in the first place?
currently no competition

24. Vista e  b   j  Define physics objects Estimate backgrounds
Filter events of interest b  p p  j 
Fit for experimental & theoretical fudge factors
Simulate detector response
(mis)Id
reconstructed e    j b
0.91
0.02
0.001
0.07
1e-3
0.87
0.10
0.90
0.81
0.19
1e-4
2e-6
3e-3
6e-4 1
2e-3
5e-3
8e-4
0.60
0.40
true

25. Discovery threshold 5
CDF + 5 DØ 7

26. Not combining CDF and D data (in a global Tevatron analysis)
delays a Fermilab discovery by 1 year

27. The solution to the “LHC Inverse Problem”
Summary
Interpreting new frontier energy collider physics Bard
The solution to the “LHC Inverse Problem”
Quickly testing specific hypotheses Quaero
Finding an excess Sleuth
Systematically understanding the data in the first place Vista
Special thanks to:
CERN
DESY
Fermilab
and many others