The Future is Open · Jesse Thaler — The Future is Open: Jet Substructure with CMS Public Data 3 Exposing the QCD Splitting Function with CMS Open Data Andrew Larkoski,1,* Simone

Jesse Thaler — The Future is Open: Jet Substructure with CMS Public Data

CMS Week, CERN — June 25, 2018

1

Jesse Thaler

The Future is OpenJet Substructure with CMS Public Data

Jesse Thaler — The Future is Open: Jet Substructure with CMS Public Data 2

CMS and CERN are pioneering the release of research-grade public collider data

2014 2015 2016 2017 2018 2019 2020 2021

2011A 2012B/C2010B

→


Exposing the QCD Splitting Function with CMS Open Data

Andrew Larkoski,1,*

Simone Marzani,2,†

Jesse Thaler,3,‡

Aashish Tripathee,3,§

and Wei Xue3,∥

1Physics Department, Reed College, Portland, Oregon 97202, USA

PRL 119, 132003 (2017) P HY S I CA L R EV I EW LE T T ER Sweek ending

29 SEPTEMBER 2017

2014 2015 2016 2017 2018 2019 2020 2021

First Publication

MODMIT Open Data

2011A 2012B/C2010B

→


Exposing the QCD Splitting Function with CMS Open Data

Andrew Larkoski,1,*

Simone Marzani,2,†

Jesse Thaler,3,‡

Aashish Tripathee,3,§

and Wei Xue3,∥

1Physics Department, Reed College, Portland, Oregon 97202, USA

PRL 119, 132003 (2017) P HY S I CA L R EV I EW LE T T ER Sweek ending

29 SEPTEMBER 2017

2014 2015 2016 2017 2018 2019 2020 2021

First Publication

MODMIT Open Data

2011A 2012B/C2010B

A Milestone for Public Collider Data

A Milestone for Jet Physics

An Opportunity/Challenge for our Community


Viability of public collider datadepends on interest/enthusiasmof particle physics community

Highlight the opportunitiesExpose the challengesInspire you to help

Goals of this talk:


The Future of Public Collider Data

Jet Substructure and QCD Splittings

Using the CMS Open Data

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CMS 2010 Open Data

Theory (MLL; all)

Pythia 8.219

Herwig 7.0.3

Sherpa 2.2.1

pPFCT > 1.0 GeV

AK5; |η| < 2.4

pjetT > 150 GeV

SD: β = 0, zcut = 0.1

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Outline

Recent progress processing the 2011 dataset

Highlights from our 2010 publications

Back to the future with ALEPH data





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CMS 2010 Open Data

Theory (MLL; all)

Pythia 8.219

Herwig 7.0.3

Sherpa 2.2.1

pPFCT > 1.0 GeV

AK5; |η| < 2.4

pjetT > 150 GeV

SD: β = 0, zcut = 0.1

0.0 0.1 0.2 0.3 0.4 0.5 0.6

Track zg

0.5

1.0

1.5

2.0

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Pyth

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November 2014:!

Run 2010B7 TeV, 32 pb–1

!

>20 TB, no MC!

(First publication: QCD)

April 2016:!

Run 2011A7 TeV, 2.5 fb–1

!

>100 TB, with MC!

(In the pipeline: BSM, ML)

opendata.cern.ch/research/CMS

December 2017:!

Run 2012B/C8 TeV, 11.6 fb–1

!

>1 PB, with MC

Kati Lassila-Perini,Achim Geiser, ...

http://opendata.cern.ch/research/CMS


The MIT Open Data Team

2010QCD:

Aashish Tripathee Wei Xue Simone MarzaniAndrew Larkoski Summer intern:Alexis Romero

CMS advice:Sal Rappoccio

2011BSM:

Wei XueMatt Strassler Yotam Soreq Cari Cesarotti Raffaele D'Agnolo

2011ML:

Radha Mastandrea Preksha Naik …

Today:very preliminary 2011 results(only 16%, still debugging)

Patrick Komiske


Key Challenge: Initial Data Processing

CernVM + CMSSW 5.3.32 (for 2011)!

AOD Format (CMS Root)RAW → RECO → “Analysis Object Data”!

Access via XRootD, write custom EDAnalyzer

For novices, very steep learning curve for using Rootand understanding overall data structure (esp. triggers)

Jet Primary Dataset: 4.7 TB for 3 million AOD eventsDaunting amount of information!


Our Strategy: Simplified Analysis Framework

MOD

MODProducer + MODAnalyzer + FastJet 3.3.1!

MOD Format (ASCII)For 2010: Cross-check with flat Root n-tuples!

Access via External Hard Drive

Text files as educational tool and debugging strategyAccess only essential information, sacrifice flexibility

Jet Primary Dataset: ~500 GB for 3 million MOD eventsNew for 2011: Separate processing for triggers/luminosity


Example MOD Metadata (Simplified)

New for 2011: Effective luminosity information per trigger

BeginFile Version 6 CMS_2011A Data Jet !# File Filename TotalEvents ValidEvents IntLumiDel IntLumiRec File A850-02163E008D77 30284 29057 895036.1 884409.2 !#Block RunNum LumiBlock Events Valid? IntLumiDel IntLumiRec Block 160578 366 53 1 28.6 27.5 Block 160578 367 58 1 28.6 27.5 Block 160578 368 38 1 28.6 27.5 Block 160578 369 40 1 28.6 27.5 Block 160578 370 57 1 28.6 27.5 Block 160578 371 46 1 28.6 27.5 Block 160578 372 37 1 28.6 27.5 ... !# Trig Name Present Valid Fired EffLumiDel EffLumiRec AvePrescale Trig HLT_Jet240_v2 16530 9 1 27228.1 27026.7 3.0 Trig HLT_DiJetAve140U_v4 13754 5 1 11705.3 11582.4 1.0 Trig HLT_Jet240_v1 13754 5 1 18387.4 18205.5 1.0 Trig HLT_Jet150_v2 16530 9 2 2722.8 2702.6 30.0 Trig HLT_Jet190_v2 16530 9 2 8168.4 8108.0 10.0 Trig HLT_Jet190_v1 13754 5 2 6939.9 6872.4 3.0 Trig HLT_DiJetAve15U_v4 13754 5 1 1.0 1.0 7500.0 Trig HLT_DiJetAve110_v2 11772 3 1 358.3 356.0 75.0 ... !EndFile


Example MOD Metadata (Simplified)

New for 2011: Effective luminosity information per trigger

BeginFile Version 6 CMS_2011A Data Jet !# File Filename TotalEvents ValidEvents IntLumiDel IntLumiRec File A850-02163E008D77 30284 29057 895036.1 884409.2 !#Block RunNum LumiBlock Events Valid? IntLumiDel IntLumiRec Block 160578 366 53 1 28.6 27.5 Block 160578 367 58 1 28.6 27.5 Block 160578 368 38 1 28.6 27.5 Block 160578 369 40 1 28.6 27.5 Block 160578 370 57 1 28.6 27.5 Block 160578 371 46 1 28.6 27.5 Block 160578 372 37 1 28.6 27.5 ... !# Trig Name Present Valid Fired EffLumiDel EffLumiRec AvePrescale Trig HLT_Jet240_v2 16530 9 1 27228.1 27026.7 3.0 Trig HLT_DiJetAve140U_v4 13754 5 1 11705.3 11582.4 1.0 Trig HLT_Jet240_v1 13754 5 1 18387.4 18205.5 1.0 Trig HLT_Jet150_v2 16530 9 2 2722.8 2702.6 30.0 Trig HLT_Jet190_v2 16530 9 2 8168.4 8108.0 10.0 Trig HLT_Jet190_v1 13754 5 2 6939.9 6872.4 3.0 Trig HLT_DiJetAve15U_v4 13754 5 1 1.0 1.0 7500.0 Trig HLT_DiJetAve110_v2 11772 3 1 358.3 356.0 75.0 ... !EndFile

Effective Luminosity per Trigger Testing Trigger Consistency


Example MOD Event (Simplified)BeginEvent Version 6 CMS_2011A Data Jet !# /Run2011A/Jet/MOD/12Oct2013-v1/20000/000D4260-D23E-E311-A850-02163E008D77.mod !#Cond RunNum EventNum LumiBlock NPV Timestamp msOffset Cond 160578 38142433 366 4 1300254008 84656 !#Trig Name Prescale_1 Prescale_2 Fired? Trig HLT_DiJetAve30U_v4 1 15 0 Trig HLT_DiJetAve50U_v4 1 3 1 Trig HLT_Jet110_v1 1 1 1 ... !# AK5 px py pz energy jec area no_of_const neu_had_frac ... AK5 -48.53 91.23 922.46 928.25 1.15 0.77 3 0.17 ... AK5 27.14 -27.95 -176.24 180.60 1.11 0.71 14 0.11 ... AK5 6.87 -27.39 -127.71 130.89 1.13 0.59 10 0.14 ... ... # PFC px py pz energy pdgId PFC 3.05 -2.27 -18.08 18.48 211 PFC 3.51 -3.48 -21.66 22.22 211 PFC 2.83 -3.01 -20.00 20.42 -211 PFC 2.89 -2.37 -18.40 18.77 211 PFC 1.21 -1.31 -7.58 7.79 -211 PFC 1.62 -2.72 -12.17 12.58 -211 PFC 7.15 -7.56 -46.86 48.01 22 ... !EndEvent

Crucial: JEC factors, jet quality criteria, and particle flow candidates


Example MOD Event (Simplified)BeginEvent Version 6 CMS_2011A Data Jet !# /Run2011A/Jet/MOD/12Oct2013-v1/20000/000D4260-D23E-E311-A850-02163E008D77.mod !#Cond RunNum EventNum LumiBlock NPV Timestamp msOffset Cond 160578 38142433 366 4 1300254008 84656 !#Trig Name Prescale_1 Prescale_2 Fired? Trig HLT_DiJetAve30U_v4 1 15 0 Trig HLT_DiJetAve50U_v4 1 3 1 Trig HLT_Jet110_v1 1 1 1 ... !# AK5 px py pz energy jec area no_of_const neu_had_frac ... AK5 -48.53 91.23 922.46 928.25 1.15 0.77 3 0.17 ... AK5 27.14 -27.95 -176.24 180.60 1.11 0.71 14 0.11 ... AK5 6.87 -27.39 -127.71 130.89 1.13 0.59 10 0.14 ... ... # PFC px py pz energy pdgId PFC 3.05 -2.27 -18.08 18.48 211 PFC 3.51 -3.48 -21.66 22.22 211 PFC 2.83 -3.01 -20.00 20.42 -211 PFC 2.89 -2.37 -18.40 18.77 211 PFC 1.21 -1.31 -7.58 7.79 -211 PFC 1.62 -2.72 -12.17 12.58 -211 PFC 7.15 -7.56 -46.86 48.01 22 ... !EndEvent

Crucial: JEC factors, jet quality criteria, and particle flow candidates

Trigger Turn-on Behavior Hardest Jet pT

0 100 200 300 400 500 600 700 800

Trigger Jet pT [GeV]

0.7

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1.0

1.1

1.2

1.3

Cro

ssS

ect

ion

Rati

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480390

310270

210150

11090

AK5; |η| < 2.4

Preliminary (16%)

Jet60 / Jet30

Jet80 / Jet60

Jet110 / Jet80

Jet150 / Jet110

Jet190 / Jet150

Jet240 / Jet190

Jet300 / Jet240

Jet370 / Jet300

CMS 2011 Open DataCMS 2011 Open Data

New for 2011:Detector Simulated Data (!)

10−810−710−610−510−410−310−210−1100101102103104105106

Dif

f.C

ross

Sect

ion

[pb/G

eV

]

Preliminary (16%)

CMS 2011 Open Data

Pythia 6 Tune Z2 (Simulated)

Pythia 6 Tune Z2 (Truth)

CMS 2011 Open Data

AK5; |η| < 2.4

pjetT > 90 GeV

0 200 400 600 800 1000 1200 1400 1600 1800

pT [GeV]

0.5

1.0

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Sim

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ted


Basic Jet PropertiesPseudorapidity

Jet Mass (without JMC)

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[nb]

Preliminary (16%)

CMS 2011 Open Data



CMS 2011 Open Data

AK5

pjetT > 270 GeV

−4 −3 −2 −1 0 1 2 3 4

η

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CMS 2011 Open Data



CMS 2011 Open Data

AK5; |η| < 2.4

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0 10 20 30 40 50 60 70 80 90

Mass [GeV]

0.5

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Track Multiplicity

Expected mismatch with truth from strange hadrons (cτ0 ∈ [10,1000] mm)

Mismatch with simulated under study

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CMS 2011 Open Data



CMS 2011 Open Data

AK5; |η| < 2.4

pjetT > 270 GeV

0 10 20 30 40 50 60

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Opportunity to streamline,since steps common to almost every collider data project

Preliminary 2011 Processing:!

2 students, ~6 months!(First collider physics project,previous experience in Python/C++,using template from 2010 analysis)

MOD





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CMS 2010 Open Data

Theory (MLL; all)

Pythia 8.219

Herwig 7.0.3

Sherpa 2.2.1

pPFCT > 1.0 GeV

AK5; |η| < 2.4

pjetT > 150 GeV

SD: β = 0, zcut = 0.1

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1.0

1.5

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Pyth

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CMS 2010 Run B7 TeV pp31.8 pb–1

!Jet Primary Dataset768,687 events(from 20 million)!HLT_Jet70UHLT_Jet100UHLT_Jet140U

MOD


Anti-kt, R = 0.5|η| < 2.4pT > 20 GeV“Loose” JQC


Anti-kt, R = 0.5|η| < 2.4Hardest pT > 150 GeV“Loose” JQC PFC pT > 1 GeV


Jet Grooming: mMDT/Soft Drop β = 0

![Larkoski, Marzani, Soyez, JDT, 1402.2657; Dasgupta, Fregoso, Marzani, Salam, 1307.0007;

see also Butterworth, Davison, Rubin, Salam, 0802.2470]

zg > zcut θgβ

zg

1–zg

θg

Drop radiation until:

zg > zcut θgβ

zg

θg



0.0 0.1 0.2 0.3 0.4 0.5

zg

0.0

0.2

0.4

0.6

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1.0

θg

pPFCT > 1.0 GeV

AK5; |η| < 2.4

pjetT > 150 GeV

mMDT / SDβ=0 : zcut = 0.1


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Collinear

dPi→ig '

2αs

πCi

dθ

θ

dz

z

Soft

Cq = 4/3Cg = 3

Soft/Collinear Behavior

z ≈ zg

zg > zcut θgβ


[Larkoski, Marzani, JDT, 1502.01719; see also Larkoski, JDT, 1307.1699]

(!)z

1–zg

θ

zg > zcut θgβ

zg

θg



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AK5; |η| < 2.4

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dPi→ig '

2αs

πCi

dθ

θ

dz

z

Soft

Cq = 4/3Cg = 3

Soft/Collinear Behavior

z ≈ zg

zg > zcut θgβ


[Larkoski, Marzani, JDT, 1502.01719; see also Larkoski, JDT, 1307.1699]

(!)z

1–zg

θ

Perfect application of CMS Open Data

Benefits from low trigger thresholds and low pileup

2010 data ⇒ 2014 release ⇒ 2015 idea ⇒ 2017 analysis


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CMS 2010 Open Data

Theory (MLL)

Pythia 8.219

Herwig 7.0.3

Sherpa 2.2.1

pPFCT > 1.0 GeV

AK5; |η| < 2.4

pjetT > 150 GeV


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zg

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Initial 2011 Results2010 Analysis

[Larkoski, Marzani, JDT, Tripathee, Xue, 1704.05066]

zg

Exposing the QCD Splitting Function

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Preliminary (16%)

CMS 2011 Open Data



CMS 2011 Open Data

AK5; |η| < 2.4

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Clear impact from detector(N.B.: no PFC pT cut imposed)





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Theory (MLL; all)

Pythia 8.219

Herwig 7.0.3

Sherpa 2.2.1

pPFCT > 1.0 GeV

AK5; |η| < 2.4

pjetT > 150 GeV

SD: β = 0, zcut = 0.1

0.0 0.1 0.2 0.3 0.4 0.5 0.6

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V. ADVICE TO THE COMMUNITY

A. Challenges

B. Recommendations

VI. CONCLUSION

As the LHC explores the frontiers of scientific knowl-

edge, its primary legacy will be the measurements and

discoveries made by the LHC detector collaborations. But

there is another potential legacy from the LHC that could be

just as important: granting future generations of physicists

access to unique high-quality data sets from proton-proton

collisions at 7, 8, 13, and 14 TeV.

In our view, the best way to build a legacy data set is to

Jet substructure studies with CMS open data

Aashish Tripathee,1,*

Wei Xue,1,†

Andrew Larkoski,2,‡

Simone Marzani,3,§

and Jesse Thaler1,∥

1

PHYSICAL REVIEW D 96, 074003 (2017)


E.g. ALEPH Confronts the CMS Ridge

[Badea, Baty, Chang, Innocenti, Yen-Jie Lee, Maggi, McGinn, Peters, Sheng, JDT, appeared at Quark Matter 2018]

pp

pp pPb Pb PbPb

vs.e+e–

1990–95 e+e– data

2010 pp surprise!

⇒

2018 e+e– analysis

Competes with needs

of the collaboration

Less impact on

the target audience


Different Options for “Public Data”

Audience

Timing

Event Displays

Instant Quarter Year Decade

Outreach

Archival

Education

Few Years

Research

Balance

openness and

priority

Competes with needs

of the collaboration

Less impact on

the target audience


Different Options for “Public Data”

Audience

Timing

Event Displays

Instant Quarter Year Decade

Outreach

Archival

Education

Few Years

Research


Data preservation (and outside analyses)require significant resources:

People, time, ideas, and money

To help justify these resources,let me address three common concerns

about public collider data raised by our work

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Theory (MLL)

Pythia 8.219

Herwig 7.0.3

Sherpa 2.2.1

pPFCT > 1.0 GeV

AK5; |η| < 2.4

pjetT > 150 GeV


0.01 0.02 0.05 0.10 0.20 0.50 1.00

θg

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dσ

dθg

Preliminary (16%)

CMS 2011 Open Data



CMS 2011 Open Data

AK5; |η| < 2.4

pjetT > 270 GeV


0.01 0.02 0.05 0.10 0.20 0.50 1.00

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!

“There is no way you can do an external analysis with thesame degree of sophistication as within the collaboration”

Balance between Sophistication and Exploration

Agreed (mostly)!

But with unexpected theoretical/experimental issues at play, value in exploratory studies

[Tripathee, Xue, Larkoski, Marzani, JDT, 1704.05842]


!

“This work competes with ongoing collaboration analyseswithout the scrutiny of internal review”

Synergy between Internal and External Efforts

[CMS, 1708.09429 ⇒ Phys. Rev. Lett. 120:142302]

Agreed, but fine line between “compete” and “complement”Important to have robust peer review (e.g. dual referees)

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tN1

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10 Centrality: 50-80%

PbPb

pp smeared

CMS

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1.8

-1bµ, PbPb 404 -1 = 5.02 TeV, pp 27.4 pbNN

s

gz0.1 0.2 0.3 0.4 0.5

0

gz0.1 0.2 0.3 0.4 0.5

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gz0.1 0.2 0.3 0.4 0.5

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gz0.1 0.2 0.3 0.4 0.5

0


!

“If you really wanted to do this jet substructure measurement,you should have joined CMS as an associate member”

Value of Open-Ended Investigations

Agreed, but what I really wanted to do is figure out theanswer to this question (curiosity-driven research)


The CMS Open Data is a fantastic resource,with many exciting applications

My View

Stress-testing archival data strategies

Enabling exploratory/proof-of-principle studies

Facilitating dialogue between theory and experiment

Educating future scientists

Researching physics in and beyond the standard model

These are only possible with sustainedinvestment in public data initiatives





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CMS 2010 Open Data

Theory (MLL; all)

Pythia 8.219

Herwig 7.0.3

Sherpa 2.2.1

pPFCT > 1.0 GeV

AK5; |η| < 2.4

pjetT > 150 GeV

SD: β = 0, zcut = 0.1

0.0 0.1 0.2 0.3 0.4 0.5 0.6

Track zg

0.5

1.0

1.5

2.0

Rati

oto

Pyth

iaSummary

Unique collider data set, ideal for exploratory studies

Exposing the universal singularity structure of gauge theories

Sustained investment from outreach to research to archives


Backup Slides


Additional 2011 PlotsAzimuth

Track Mass

Constituent Multiplicity

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CMS 2011 Open Data

AK5; |η| < 2.4

pjetT > 270 GeV

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Constituent Multiplicity

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CMS 2011 Open Data



CMS 2011 Open Data

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pjetT > 270 GeV

0 10 20 30 40 50 60

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CMS 2011 Open Data



CMS 2011 Open Data

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pjetT > 270 GeV

0 π/2 π 3π/2 2π

φ

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Sewing Together Simulated Data Samples

0 100 200 300 400 500 600 700

Hardest Jet pT [GeV]

10−3

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10−1

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Preliminary (16%)

pGenT ∈ [15,30] GeV




pGenT ∈ [120,170] GeV

pGenT ∈ [170,300] GeV

pGenT ∈ [300,470] GeV


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Hardest Jet pT [GeV]

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Preliminary (16%)

pGenT ∈ [470,600] GeV

pGenT ∈ [600,800] GeV

pGenT ∈ [800,1000] GeV

pGenT ∈ [1000,1400] GeV

pGenT ∈ [1400,1800] GeV

pGenT ≥ 1800 GeV



Textbook QCD: Universal Collinear Limit

Collinearsingularity

Softsingularity

dPi→ig '

2αs

πCi

dθ

θ

dz

z

x

1→2

2z

1–zθ

Splitting Function

Cq = 4/3Cg = 3

≈

2. . .

. . .

2. . .

. . .

2→n 2→n–1


A Quad-Jet Puzzle in Archival ALEPH Data

[Kile, von Wimmersperg-Toeller, 1706.02242, 1706.02255, 1706.02269]

2: ∆ for 45 GeV < Σ < 61 GeV.

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.00 G

eV

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LEP2 ALEPH archived dataSherpa MEPS@LO

4fWW

4fZZother

Nfit = 223.28 ± 61.41Mean = 53.97 ± 1.24

Width = 3.55 ± 1.14

0.6

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1

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(a)

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LEP2 ALEPH archived data

SHERPA MEPS@LO

4fWW

4fZZ

Other

0.6

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1

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1.4

-100 -80 -60 -40 -20 0 20 40 60 80 100

(?!)

Sym-Dijet Mass Average Sym-Dijet Mass Difference


Example of stress-testing archival data strategies


New: Public neutrino data!

Derived data from 2008-2012 ⇒ Released May 2018

Documents

The Future is Open · Jesse Thaler — The Future is Open: Jet Substructure with CMS Public Data 3 Exposing the QCD Splitting Function with CMS Open Data Andrew Larkoski,1,* Simone