Physics at 7 TeV With Less Than 1 fb -1

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Physics at 7 TeV

With Less Than 1 fb ^-1 Physics at 7 TeV

With Less Than 1 fb ^-1

Scott Thomas Scott Thomas Rutgers University

US CMS Meeting

May 7, 2010

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Focus Rutgers: Early – Medium Term Physics

Open String Di-Jet Regge Resonances

Benchmarks / Parameter Spaces

Multi-Leptons, Photons, Higgs, Z’s, HITs from . Split Messenger GMSB

Model Independent Combination of Multiple Channels

Consistent On-Shell Effective Theory for . Cascade Decay Correlations

Top Quark

. Mass, Spin, New Physics in Decay Correlations . MET Background . Kinematic Fits, …

SUSY Di-Object Correlations

NNOMET Procedure for Extracting Masses and Spins

Multi-Jet Resonances

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Open String Di-Jet Regge Resonances

High p_T: σσσσ(pp jj) Largest – First Place to Look . for New Physics

String Scale αααα^′′′′ ^-1 = m_s² Could be O(TeV)

SU(3)

SU(2)

Quark

W-Boson Gluon

Quarks, Gluons = Open String Modes on D-Branes

Open String Regge Excitations - Any Realization of . String Theory - Observable for m_s = O(TeV)

Tower of Excitations for Gluon, All Quarks, … g^* , q^* m_n² = n m_s² n=0,1,2,3,… Equally Spaced in m² Degenerate (up to small finite corrections)

Regge Excitation Spins ∆∆∆∆ J = 0,1,…,n

(Lath, Rose, Kilic, Winter, Halkiadakis, Thomas)

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String-String Scattering

=

∑ ∑ ∑ ∑ _n

_n

+ ∑ ∑ ∑ ∑ _n

ⁿ

Open String Di-Jet Regge Resonances

Veneziano Form Factor

Crossing Symmetry: x ↔↔↔↔ y

s-Channel Resonances for Entire |Matrix Element|² m_s = O(TeV) - Significant Modification of Di-Jets

Regge Level Spin

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Open String Di-Jet Regge Resonances

Di-Jets

1. s ∼∼∼∼ m_s² Regge Resonances m_n² = n m_s² , ΓΓΓΓ_n = ΓΓΓΓ_n(m_s) 2. s ≪≪≪≪ m_s² Contact Interaction Form Factor

Previous Work

Cullen, Perlestein, Peskin e⁺e^- Colliders

Anchordoqui, Goldberg, Lust, Tried To Interpret Open String Amplitudes

. Nawata, Stieberger, Taylor Only Some Channels

. No Quantum Interference . Widths – Incoherent Limit Bad

Veneziano Monte Carlo Generator (Can Kilic)

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Open String Di-Jet Regge Resonances

Model Independent Probe of String Theory . (Minimal Regge Resonances – Actual Model Likely Stronger)

Incorporate String Regge Resonances into Model List for . Di-Jet Resonance Search (Contacted Rob Harris)

Contact Interaction Search Most Sensitive (Probe m_s² > s)

Constructive Interference

Destructive Interference

1^st Resonance BIG –

. All Channels, . Gluon, All Quarks, . Multiple Spins

m_n² Spacing Γ

Γ Γ

Γ_n Grow Rapidly with n

Constructive-Destructive . Opposite Standard g^*, q^*

7 Tev

Parton Level

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Benchmarks / Parameter Spaces

Cautionary Tale of Two Collaborations:

Over Many Decades Theorists Developed a Framework for New Astro Physics A Standard Benchmark for the New Astro Physics Emerged

When Experimental Advances Finally Probed the New Astro Physics

Collaboration A –

Developed Search Strategy Based on the Benchmark - . Analyzed an Enormous Amount of Data with no Success

Collaboration C –

Ignored the Benchmark - First Searched Quickly through . Data for Signatures that Could be Discovered First

Discovered New Astro Physics !!

. (Immediately Confirmed by Collaboration A in Existing Data)

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Benchmarks / Parameter Spaces

Collaboration A –

Collaboration C –

This Already Happened in the Search for Extrasolar Planets !

Benchmark = Jupiter mass Planet with O(10) yr Orbit Discovery = Jupiter mass Planet with O(few) day Orbit

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Benchmarks / Parameter Spaces

Collaboration A –

Collaboration C –

This Already Happened in the Search for Extrasolar Planets !

Benchmark = Jupiter mass Planet with O(10) yr Orbit Discovery = Jupiter mass Planet with O(few) day Orbit

Lesson

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Benchmarks / Parameter Spaces

Over Many Decades Theorists Developed a Framework for New SUSY Physics A Standard Benchmark for the New SUSY Physics Emerged

When Experimental Advances Finally Probed the New SUSY Physics

Collaboration A –

Collaboration C –

Discovered New SUSY Physics !!

This Could Happen in the Search for New Physics at the LHC

Benchmark = … , mSUGRA , … (See Backup Slides for Comments) Discovery = … , SUSY with Compressed Spectrum , … , ???

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SUSY Benchmarks / Parameter Spaces

Search First for What Can be Discovered First

Gauge Ordered Spectrum . “Natural Expectation”

Compressed Spectrum

“Reasonable Expectation”

Y. Gershtein

(Gershtein, Shih, Thomas)

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SUSY Benchmarks / Parameter Spaces

Discovery Potential of Gauge Ordered vs Compressed Spectra Minimal Gauge Mediation:

Gauge Ordered Spectrum Weak Production Dominates

Reach not Far Beyond Tevatron

General Gauge Mediation:

Compressed Spectrum Strong Production Dominates

Reach Rapidly Exceeds Tevatron

Y. Gershtein NNN

N₅₅₅₅=1=1=1=1

(Widely Held View – Even Among Theorists who Should Know Better)

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Gauge Mediation with Split Messengers

100

120 140

35 000 40 000 45 000 50 000 55 000 60 000 65 000

10 000 20 000 30 000 40 000 50 000 60 000

Independent SUSY Breaking for Minimal Messengers

L, d

Simple Version (Linda Carpeter) ΛΛ

ΛΛ_LLLL ((((TeVTeVTeV) ) ) ) TeV ΛΛΛΛ ^dddd((((TeVTeVTeVTeV))))

100100 100100 120120 120120

Benchmark Points,

. Lines/Slopes, . Manifolds

140 140 140 140

Gauge Ordered . Spectra

Compressed . Spectra

400 400 400 400 800 800 800 800 1200 12001200 1200 400400

400400 500500500500

50 50 50 50 40

40 40

40 60606060 5050

5050 40 40 40 40

20 20 20 20 30 30 30 30 60 60 60 60

mmmmglu ino gluin ogluino gluin oGeVGeV((((GeVGeV) ) ) ) mm

mm_wino_wino_wino_wino ((((GeVGeVGeV) ) ) ) GeV

M in im a l G a u g e M e d ia tio n M in im a l G a u g e M e d ia tio n M in im a l G a u g e M e d ia tio n M in im a l G a u g e M e d ia tio n mm

mm_Slepton_Slepton_SleptonSleptonRRRR ((((GeVGeVGeV) ) ) ) GeV

NNN N₅₅₅₅=3=3=3=3

(R. Gray, Somalwar, Park, Zhao, Thomas)

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1

2

5

10

15

35 000 40 000 45 000 50 000 55 000 60 000 65 000

20 000 30 000 40 000 50 000 60 000

0.5 0.6

0.7 0.8

35 000 40 000 45 000 50 000 55 000 60 000 65 000

20 000 30 000 40 000 50 000 60 000

Gauge Mediation with Split Messengers

ΛΛ

0.70.7

0.70.7 0.60.60.60.6 0.50.50.50.5

400400

400400 500500500500

50 50 50 50 40

40 40

40 60606060 5050

5050 40 40 40 40

20 20 20 20 30 30 30 30 60 60 60 60

mm

M in im a l G a u g e M e d ia tio n M in im a l G a u g e M e d ia tio n M in im a l G a u g e M e d ia tio n M in im a l G a u g e M e d ia tio n Weak

Weak Weak

Weak σσσσ ((((pbpbpbpb) 7 ) 7 ) 7 ) 7 TeVTeVTeVTeV

ΛΛ

1010 10105555 1111

400400

400400 500500500500

50 50 50 50 40

40 40

40 60606060 5050

5050 40 40 40 40

20 20 20 20 30 30 30 30 60 60 60 60

mmmmglu ino gluin ogluino gluin oGeVGeV((((GeVGeV) ) ) ) mm

M in im a l G a u g e M e d ia tio n M in im a l G a u g e M e d ia tio n M in im a l G a u g e M e d ia tio n M in im a l G a u g e M e d ia tio n Total

Total Total

Total σσσσ ((((pbpbpbpb) 7 ) 7 ) 7 ) 7 TeVTeVTeVTeV

0.80.8 0.80.8

2222 20 20 20 20 NNN

N₅₅₅₅=3=3=3=3 NNNN₅₅₅₅=3=3=3=3

(Most of Plane Not Excluded by Tevatron)

400 400 400 400 800 800 800 800 1200 12001200 1200

(R. Gray, Somalwar, Park, Zhao, Thomas)

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Neutralino NLSP γγγγ, Higgs, Z + Goldstino (MET) Slepton Co-NLSP Leptons, Tau + Goldstino (MET) Stau NLSP Tau + Goldstino (MET)

Squark, Gluino Jets + Goldstino (MET)

MetaStable Slepton, Stau Massive - Charged Tracks MetaStable Gluino, Stop Charge Exchange Tracks, …

Metasble Neutralino, Slepton Displaced γγγγ , Higgs, Z , . Kink Tracks, …

Gauge Mediation with Split Messengers

Split GMSB Parameter Spaces Useful for Studies …

Rutgers Modification of IsaSugra 7.80 for Split GMSB can be Made Available to Anyone in CMS

(Currently Beta Version , Backward Compatible)

(R. Gray, Somalwar, Richards, Panwalkar, Contreras, Zywicki, Zhao, Park, Thomas)

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Physics Interpretation of Results (The Inverse Problem)

Benchmark Points, Lines, Manifolds, …

Can be Useful for Presenting Null Results –

. Quantify How Well Probe Specific Models . But Then Presentation of Results – Can Be Very Model Specific

Unlikely to be as Useful if Postive Results -

. Probably Won’t Capture All Features of Signal

Example – Tevatron Tri-Lepton Searches

mSUGRA parameter space

(see backup Slides for comments)

Search Results in this form:

Mapping from σσσ····σ Br Results . in Multiple Channels Onto . Model Space n =0,1,2,3

ττττ

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Physics Interpretation of Results (The Inverse Problem)

Benchmark Points, Lines, Manifolds, …

Can be Useful for Presenting Null Results –

. Quantify How Well Probe Specific Models . But Then Presentation of Results – Can Be Very Model Specific

Unlikely to be as Useful if Postive Results -

. Probably Won’t Capture All Features of Signal

Example – Tevatron Tri-Lepton Searches

mSUGRA parameter space

(see backup Slides for comments)

Search Results in this form:

Mapping from σσσ····σ Br Results . in Multiple Channels Onto . Model Space n =0,1,2,3

ττττ

Any Point in Model Space ⇒⇒⇒⇒ Model Dependent

Correlation Among Spectrum, σσσσ, and Br’s Information Lost 17

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Physics Interpretation of Results

(Dube, Glatzer, Somalwar, Sood, Thomas)

1. Hypothesis for New Process

Alternative Model Independent Method of Presenting Results . Factorize Mapping: Data Model Space

2. Parameterize Experimental Acceptance or

. σσσ ····σ Br Br Sensitivity in Each Channel as Br Br . function of masses Only (Br’s=1)

3. Map Results Onto Any Model

*

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http://www.physics.rutgers.edu/pub-archive/0901/

Physics Interpretation of Results

(Dube, Glatzer, Somalwar, Sood, Thomas)

Factorized Mapping Method: Data Model Space . (Solve the Inverse Problem)

Simple Method to Probe Many Models . (Promises to be More Efficient Than Other Suggestions for . Filling Model Spaces with Full Mapping)

Another Means to Present Experimental Results User Friendly (Theorist and Experimentalist)

Sensitivity Parameterizations for CDF . Tri-Lepton Results Available at (Steps 1 + 2)

arXiv:0808.1605 [hep-ph]

Plan to Quantify Multi-Channel Multi-Lepton Searches . in this Way (in Addition to Traditional Model Spaces)

(R. Gray, Somalwar, Richards, Panwalkar,

Contreras, Zywicki, Park, Zhao, Thomas) 19

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Top Quarks

Invariant Kinematic Distributions - . Extracting Top Quark Mass

1/ΓdΓ\dm bl

m_{b l}

Three Novel Methods for Extracting Top Mass from Templates 1. m_bl Scale

2. m_bl Shape

3. m_µ_µ_µ_µ _lfrom b µµµµ

Total

e, µ

τ → e, µ

(Grasser, Shelton, Thomas, Lath, Halkiadakis, Schnetzer)

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Top Quarks

Theory Study –

Full Simulations . Needed to

Generate Templates

(Grasser, Shelton, Thomas, Lath, Halkiadakis, Schnetzer)

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Top Quarks

MET Characterization/Calibration (Park, Lath, Thomas)

For Unpolarized pp W X l νννν X the p _T Distribution of . Lepton and Neutrino are Identical . Even Though There is a Charge Asymmetry

W-Boson Leptonic Decay

For Unpolarized pp t t b b l l νννν νννν the . Vector Sum p_T,1+2 Distribution of Lepton₁+Lepton₂

. and for Neutrino₁ + Neutrino₂ are Identical . Even Though There is a Charge Asymmetry

Parton Level MET Distribution Identical to Vector Sum P_T Distribution of Lepton₁+Lepton₂

Provides In Situ Measurable Handle on MET from Tops !!

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Lepton₁

Lepton₁ + Lepton₂ Neutrino₁

Nuetrino₂ Neutrino₁ + Neutrino₂

Top Quarks

(Park, Lath, Thomas)

MET Lepton₁ + Lepton₂

Parton Level Dileptonic Top . 14 TeV

. 130 pb^-1

1. Calibrate MET with Distributions in Top Dominated Control Region – 2. Search for New Physics Contamination from Deviations in Signal Region

Technique for Tops Subsequently Adopted by Santa Barbara Group

Gev Gev

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Top Quarks

Kinematic Invariants (Lath, Schnetzer, Hits, Thomas)

… …

Hadronic Top - Invariant Sub-Matrix Element

Use

NOT

Common Mistake

For i,j,k Jets from Hadronic Top

Ordered List m_ij² < m_ik² < m_jk²

m_W² ∈∈∈∈ (m_ij² , m_ik²) Always Lowest Two Pairs

m_W² ≠≠≠≠ m_jk² Never Highest Pair . (Ignoring Jet Resolution) 24

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Consistent On-Shell Effective Theory

for Cascade Decay Correlations (COSET)

(Thomas, Graesser, Shelton, Park)

Develop Effective Field Theory - . Calculate Cascade Decay Correlations

Systematic Expansion in ΓΓΓΓ/m , m/M

Provides Framework to Consider Wide Class . Standard Model + New Physics Processes

. Correlations in Generalized Multi-Dimensional . Dalitz Spaces of Invariants

Leading Order in COSET Expansion:

Invariant Mass Distributions in Generalized Dalitz Space

– . Uniquely Determined by Masses and Spins . (No Arbitrary Couplings)

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COSET – Sequential Two-Body Cascade Decay Correlations

½

0

½

½ ½

0

½ 0

½

0

½ 0

½

Triangle Hump Half-Cusp

Chiral Insertion

Chiral Structure Unique - Independent of Majorana/Weyl, Dirac, PseudoDirac, …

(1 / Γ)( d Γ/ dx) (1 / Γ)( d Γ/ dx) (1 / Γ)( d Γ/ dx)

x x x

Only Possibilities for Adjacent Branch Correlations with J=0, ½ (Almost) Complete List of Correlations - Three Sequential Decays J 1

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(Thomas, Graesser, Shelton)

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Discerning SUSY In

Cascade Decay Correlations

(Template) Search for Correlations in Data

Limited Set of Possible Adjacent Branch Correlations : J=0, ½ Adjacent Di-Lepton Distributions – All Possible SUSY Spectra

SUSY

Distinctive Patterns

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(Thomas, Graesser, Shelton)

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Next To Nearest OnShell Mass Extraction Technique (NNOMET)

Correlations Uniquely Determined by Masses and Spins

(SUSY) Three Sequential Cascade Decays

Jets+

Leptons +MET

Includes Combinatoric

“Non-Confusion” for Lepton_1,2

Distribution In 3D Dalitz Space Uniquely Determined in Terms of 4 Mass

Parameters 4 Sparticle Masses in Cascade Decay Tree

m²_jl

d Γ/ d m jl

m²_jl Does Not Use Measurent of MET

m²_ll m²_jl

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(Lath, Thomas, Park, Chavez)

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Next To Nearest OnShell Mass Extraction Technique (NNOMET)

LM1 Benchmark . TDR Cuts , 14 TeV , 100 pb^-1

Red – SUSY Decay Sequence

Blue – SUSY “Combinatoric” Decay Sequence Green – SUSY + Top Background

Likelihood Entropy Kinematic Mass Parameters

(S+S)/B ∼∼∼∼ 1/3 O(50) SUSY Events

Form an Ensemble of All . Jets p_T > 60 GeV + 2 Leptons Multiple Entries per Event

B (GeV)

A (GeV)

Working to Extend to . Discovery Level …

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Next To Nearest OnShell Mass Extraction Technique (NNOMET)

Multi-Dimensional Dalitz Space Distributions for n-Sequential Cascade Decays - Include All Possible Invariant Correlations

Superior to Kinematic Edge, End Points, Special Points , … . (Strongest Correlations Washed Out in Projection)

Can Test Hypotheses for Spin Assignments for n ≥≥≥≥ 2 . (n=2,3 Correlations from COSET List)

Can Extend to n ≥≥≥≥ 3

. Very Strong Correlations in High Dimensional Dalitz Space . (n=2,3,4 Correlations for SUSY From COSET List)

Physics Based Correlations – Directly from COSET Formalism . (Extracting from Neural Net Seems Hopeless)

For n-Sequential Cascade Decays , n=1,2

. NNOMET Can Not Reconstruct All Masses . (Techniques That Use MET May Be Useful in These Cases)

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Extracting Hadronic Resonances

Using Jet Ensemble Correlations

(Duggan, Hidas, Bavier, Halkiadakis, Lath, Thomas)

Purely Hadronic Final States Very Difficult Great Discovery Potential … jetjet

jetjet jetjet jetjet jetjet

jetjet

j j j j j j j j j j j j pp QQ

pp QQ

mjjj

p_T,jets

Standard Techniques Fail on High Multiplicity Final States

QCD Fills Up Phase Space !!

Accept Combinatoric Confusion Form Ensemble of Permutations Invariant- Non-Invariant Correlation Extend to Other Signatures …

SUSY – Hadronic RPV Q= gQ= g~~

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Cut Accept

7 TeV 10 pb^-1

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Conclusion

We Theorists are Here to Contribute Constructively …

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Back Up Slides

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Benchmarks / Parameters Spaces

Pre-Discovery:

Generators for Signatures – Develop + Optimize Searches Every Benchmark has Particular Details –

. Easy to get too Invested Theory:

Designed to Probe Underlying Theoretical Framework -

. But Actual Benchmark = Arbitrary Subspace of a . Contrived Model with Hidden Uncontrolled Assumptions …

Experiment:

Possible to Over Specialize / Optimize Search Strategy . Or Neglect Interesting Signatures Based Benchmark Details . (e.g. Constrained SUSY Based on Higgs mass, …)

Post-Discovery:

Don’t Try (Too Hard) to Jam Positive Results into Benchmark 34

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Benchmarks / Parameters Spaces

mSUGRA is Probably the Most Widely Abused . Benchmark / Parameter Space

Messenger Scale O(M_p) “Perfectly Good” Theoretical . Framework for SUSY Breaking (Hall, Lykken, Weinberg)

mSUGRA Perfectly Good Generator for Jets+Leptons+MET

But it is an Arbitrary Subspace Defined at an Inaccessible

Scale Within a Contrived

“Model” with Hidden

Uncontrolled Assumptions

So Don’t Take Fine Details Too Seriously – e.g. Higgs Mass

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Benchmarks / Parameters Spaces

mSUGRA is Probably the Most Widely Abused . Benchmark / Parameter Space

Messenger Scale O(M_p) “Perfectly Good” Theoretical . Framework for SUSY Breaking (Hall, Lykken, Weinberg)

mSUGRA Perfectly Good Generator for Jets+Leptons+MET

But it is an Arbitrary Subspace Defined at an Inaccessible

Scale Within a Contrived

“Model” with Hidden

Uncontrolled Assumptions

So Don’t Take Fine Details Too Seriously – e.g. Higgs Mass

Please Describe with Relevant Parameters (not m₀ , m_1/2 )

??

OK

If You Don’t Believe Me - . Ask Him . Yourself

??

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Physics at 7 TeV With Less Than 1 fb -1

Physics at 7 TeV

With Less Than 1 fb -1 Physics at 7 TeV

With Less Than 1 fb -1

Scott Thomas Scott Thomas Rutgers University

US CMS Meeting

May 7, 2010

Focus Rutgers: Early – Medium Term Physics

Open String Di-Jet Regge Resonances

∑ ∑ ∑ ∑ n

+ ∑ ∑ ∑ ∑ n

Open String Di-Jet Regge Resonances

Open String Di-Jet Regge Resonances

Open String Di-Jet Regge Resonances

Benchmarks / Parameter Spaces

Benchmarks / Parameter Spaces

Benchmarks / Parameter Spaces

Benchmarks / Parameter Spaces

SUSY Benchmarks / Parameter Spaces

SUSY Benchmarks / Parameter Spaces

Gauge Mediation with Split Messengers

Gauge Mediation with Split Messengers

Gauge Mediation with Split Messengers

Physics Interpretation of Results (The Inverse Problem)

ττττ

Physics Interpretation of Results (The Inverse Problem)

ττττ

Physics Interpretation of Results

Physics Interpretation of Results

Top Quarks

Top Quarks

Top Quarks

Top Quarks

Top Quarks

Consistent On-Shell Effective Theory

for Cascade Decay Correlations (COSET)

COSET – Sequential Two-Body Cascade Decay Correlations

Discerning SUSY In

Cascade Decay Correlations

Next To Nearest OnShell Mass Extraction Technique (NNOMET)

Next To Nearest OnShell Mass Extraction Technique (NNOMET)

Next To Nearest OnShell Mass Extraction Technique (NNOMET)

Extracting Hadronic Resonances

Using Jet Ensemble Correlations

Conclusion

Back Up Slides

Benchmarks / Parameters Spaces

Benchmarks / Parameters Spaces

Benchmarks / Parameters Spaces

With Less Than 1 fb ^-1 Physics at 7 TeV

With Less Than 1 fb ^-1

∑ ∑ ∑ ∑ _n

+ ∑ ∑ ∑ ∑ _n