hb Coupling at large tan b

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h-b Coupling at large tan b
The Search for SUSY Higgs
3-b tagged event
A. Haas, A. Kharchilava, G. Watts
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Higgs Production and Large tan?

• Low tan ?, ? Standard Model Higgs
• High tan ?, ? enhanced bbH
• Cross section rises like tan2?
• Recent work indicates that the LO cross-sections
  are an underestimate by a factor 3
• Some theoretical bias towards expecting tan ? gt
  30
• b-t-t Yukawa unification at the GUT scale ? mt/mb
  tan ? ?

CP-odd HiggsProduction
CP-even HiggsProduction
tan ?
3
Search Strategy
hb and hbb
Use 3 b-tags
Design Search Appropriately
Backgrounds Include
QCD bbh, bbjj, bbbb EQ/St Zb, Z, tt
4 Jet HF MC QCD not well tested design around
its use
Look for excess in di-jet mass window
Use shoulders to calibrate
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But Watch It!
Jet Double Counting!
Almost exact overlap
2nd Spectator b might think it was far forward!
Can use hb, hbb, or use spectator b pT to cut over
Thus no overlap But turn on FSR in MC
Makes Almost No difference (lt5)
Use hb only
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Trigger
QCD 3-jet rate means we cant write everything to
tape!
V10 CJT(4,5), L2(3,8)L2HT(50), L3(3,15) V11
CJT(3,5), L2(3,8)L2HT(50), L3(2,25)L3(3,15)
Done for all trigger components
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b-tagging
p13 Data
HF JES
Using the SVT algorithm
JLIP was also used as a cross check
Extra Loose Operating Point
LQ 3
hbb
B-tagging as a function of jet multiplicity was
observed flat within statistics.
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DiJet Mass Resolution
All Analysis Cuts Applied
2 highest pT jets found to give cleanest peak
JES Error Also Used
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Where We Are Headed
Fit to Window
Data

• Fitted Background
• Multijet Data

Fitted Background
bh
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Multi-jet Background
Full Multijet Sample
Calculate TRF (pT 3 Regions of h)
2-Tagged Sample
Apply TRF
3-Tagged Jet Distribution
bbbb, zbb
Fitted Background
Shapes are similar, so fit should take care of
them to first order
Fit outside to real 3 Tagged Distribution
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Fitted outside
Use a 1 s window around the Higgs mass window
But higgs gets wide at large tan b!
Optimization performed
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Errors
Systematic Errors on Acceptance ()
Systematic Errors on Backgrounds
Both b-id related and statistics 8-11 depending
upon the optimized point
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Results
Counting
TLimit
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Results

• Set limit using fitted distributions (TLimit)
• Will be down at 40 with MA100 at 1.6 fb-1
• No analysis improvements taking into account!

Search for SUSY Higgs at high tan b
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CDF/DZERO
How did that happen???

• Better understanding of MC
• We cant reproduce their analysis yet
• EB has some useful suggestions
• Different BID operating point
• Are in contact with CDF as well

On going effort thanks to the EB for their help
with this!
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Conclusions

• Preliminary limit on tan b as a function of SUSY
  Neutral Higgs Mass.
• MC Cross Checks performed for the QCD backgrounds
• ALGEN is quite close (factor of 1.1 for bbjj and
  0.65 for bbbb)
• Approved by Higgs Group
• Thanks for all your comments!
• Now in Editorial Board
• Aiming for Moriond Release
• First big meeting just occured
• Mostly small questions a few bigger ones
• Waiting to hear back from EB more detailed list
• A p14 based analysis has started