+ All Categories
Home > Documents > Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... ·...

Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... ·...

Date post: 26-Sep-2020
Category:
Upload: others
View: 6 times
Download: 0 times
Share this document with a friend
24
Experimentalists view on Shower Deconstruction Nicolas Gutierrez
Transcript
Page 1: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

Experimentalists view on Shower Deconstruction

Nicolas Gutierrez

Page 2: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

2 Using jet substructure - Oregon

Jet substructure techniques in ATLAS

Substructure techniques are usually divided in two categories, simple and complicated. Having more than two equations in the description of a particular technique do take away popularity points.

Page 3: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

3 Using jet substructure - Oregon

Jet substructure techniques in ATLAS

A second layer divides these techniques in those on which a particular group is and is not involved. No involvement usually means a technique is madness. Shower Deconstruction as a start up method could be very well placed in the complicated- madness group.

Page 4: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

4

Lets  take  one  boosted  top:    

 Fairly  boosted  pT  ~  850  GeV    Fairly  central    η  ~  -­‐0.1  

   With  a  relaAvely  large  microjet  mulAplicity  :      6  microjets      pT  from  20  up  to  400  GeV  

η

-1

-0.5

0

0.5

1

φ

0.20.4

0.60.81

1.21.4

1.61.82

2.22.4

TH

igh

pT

Low

p

Using jet substructure - Oregon

Shower Deconstruction

Page 5: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

5

η

-1

-0.5

0

0.5

1

φ

0.20.4

0.60.81

1.21.4

1.61.82

2.22.4

TH

igh

pT

Low

p

χlog -10 -8 -6 -4 -2 0 2 4 6 8 100

0.01

0.02

0.03

0.04

0.05

0.06

0.07

Shower  DeconstrucAon  χ  observable  would  be  ~  550    

Around  here  

Using jet substructure - Oregon

Shower Deconstruction

Page 6: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

6

η

-1

-0.5

0

0.5

1

φ

0.20.4

0.60.81

1.21.4

1.61.82

2.22.4

TH

igh

pT

Low

p

χlog -10 -8 -6 -4 -2 0 2 4 6 8 100

0.01

0.02

0.03

0.04

0.05

0.06

0.07

Shower  DeconstrucAon  χ  observable  would  be  ~  550    

Around  here  

There  are  more  than  1800  possible  shower  histories.    About  20  histories  have  dominaAng  weights.    Some  of  which  are  permutaAons  of  the  same  physics  case.  Reducing  the  number  to  4.  

Using jet substructure - Oregon

Shower Deconstruction

Page 7: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

7

η

-1

-0.5

0

0.5

1

φ

0.20.4

0.60.81

1.21.4

1.61.82

2.22.4

TH

igh

pT

Low

-1

-0.5

0

0.5

1

φ

0.20.4

0.60.81

1.21.4

1.61.82

2.22.4

mW  ~  77.3  GeV  

Using jet substructure - Oregon

Shower Deconstruction

Page 8: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

8

η

-1

-0.5

0

0.5

1

φ

0.20.4

0.60.81

1.21.4

1.61.82

2.22.4

TH

igh

pT

Low

-1

-0.5

0

0.5

1

φ

0.20.4

0.60.81

1.21.4

1.61.82

2.22.4 mW  ~  83.1  GeV  

Using jet substructure - Oregon

Shower Deconstruction

Page 9: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

9

η

-1

-0.5

0

0.5

1

φ

0.20.4

0.60.81

1.21.4

1.61.82

2.22.4

TH

igh

pT

Low

-1

-0.5

0

0.5

1

φ

0.20.4

0.60.81

1.21.4

1.61.82

2.22.4

mW  ~  77.3  GeV  

Using jet substructure - Oregon

Shower Deconstruction

Page 10: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

10

η

-1

-0.5

0

0.5

1

φ

0.20.4

0.60.81

1.21.4

1.61.82

2.22.4

TH

igh

pT

Low

-1

-0.5

0

0.5

1

φ

0.20.4

0.60.81

1.21.4

1.61.82

2.22.4 mW  ~  83.1  GeV  

Using jet substructure - Oregon

Shower Deconstruction

Page 11: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

η

-1

-0.5

0

0.5

1

φ

0.20.4

0.60.81

1.21.4

1.61.82

2.22.4

η

-1

-0.5

0

0.5

1

φ

0.20.4

0.60.81

1.21.4

1.61.82

2.22.4

Shower Deconstruction

η

-1

-0.5

0

0.5

1

φ

0.20.4

0.60.81

1.21.4

1.61.82

2.22.4

η

-1

-0.5

0

0.5

1

φ

0.20.4

0.60.81

1.21.4

1.61.82

2.22.4

Which  shower  is  the  right  one  ?  

We  don’t  know  !  

Let’s  take  the  QM  approach  use  them  all  through    Shower  DeconstrucAon  

Using jet substructure - Oregon 11

Page 12: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

Using jet substructure - Oregon

On the menu

Although we wont be showing any ATLAS performance plots, we hope to present a diagnosis of the technique. Something we should probably do before jumping into an actual analysis. Plots on the following slides are to be compared only to other slides on this talk. We wont be comparing Shower Deconstruction to other techniques.

12

Page 13: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

large-R-jet mass [GeV]100 150 200 250 300 350 4000

500

1000

1500

2000

2500

3000

3500

MCsmeared MC

microjet energy [GeV]10 210 310

JER

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

0.4

0.45

0.5A simple exercise      We  will  take  a  MC  sample  and  apply  a  

parameterizaAon  of  the  microjet’s  Energy  resoluAon.          Then  see  how  does  this  affect  the  performance.            Also  we  will  see  how  does  a  flat  energy  uncertainty  of  4%  affect  the  performance.    This  by  no  means  could  replace  a  full  simulaAon  of  the  detector  effects  !      

~10%  @  100  GeV  

~20%  @  20  GeV  

40-­‐50%  @  5  GeV  

Top-­‐jet  mass  distribuAon  before/a`er  smearing  

Using jet substructure - Oregon 13

Page 14: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

Samples and selections

Event cuts: Reject events with W -> l + v Require jet with mass > 120 GeV

Object selection: Clustering with AntiKt with radii parameter 1.0 Required to have |η| < 0.3 and pT ≥ 350 GeV

Binning: pT [600-800]

MC Pythia Zprime {mass 1750 GeV} Pythia8 dijets

Using jet substructure - Oregon 14

Page 15: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

Effect of microjet energy smearing on χ

χ-10 -8 -6 -4 -2 0 2 4 6 8 100

0.002

0.004

0.006

0.008

0.01MC

smeared MC

χ-10 -8 -6 -4 -2 0 2 4 6 8 100

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08MC

smeared MC

Dijets   Tops  

Using jet substructure - Oregon 15

Page 16: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

Effect of microjet energy smearing on performance

Signal Efficiency0 0.1 0.2 0.3 0.4 0.5 0.6 0.7

Fake

rate

-310

-210

-110 MCsmeared MC

Using jet substructure - Oregon 16

Page 17: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

Effect of microjet’s minimum transverse momentum

Signal Efficiency0 0.1 0.2 0.3 0.4 0.5 0.6 0.7

Fake

rate

-310

-210

-110 MC minimum pT 20MC minimum pT 10MC minimum pT 5

Using jet substructure - Oregon 17

Page 18: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

Effect of microjet’s minimum transverse momentum

Signal Efficiency0 0.1 0.2 0.3 0.4 0.5 0.6 0.7

Fake

rate

-310

-210

-110 smeared MC minimum pT 20smeared MC minimum pT 10smeared MC minimum pT 5

Using jet substructure - Oregon 18

Page 19: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

Effect of microjet energy uncertainty

χlog -10 -8 -6 -4 -2 0 2 4 6 8 100

0.002

0.004

0.006

0.008

0.01

smeared MC

smeared MC JESup

smeared MC JESdown

χlog -10 -8 -6 -4 -2 0 2 4 6 8 100

0.01

0.02

0.03

0.04

0.05

0.06

0.07 smeared MC

smeared MC JESup

smeared MC JESdown

Dijets   Tops  

Using jet substructure - Oregon 19

Page 20: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

Signal Efficiency0 0.1 0.2 0.3 0.4 0.5 0.6 0.7

Fake

rate

-310

-210

-110 smeared MCsmeared MC JESupsmeared MC JESdown

Using jet substructure - Oregon

Effect of microjet energy uncertainty

20

Page 21: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

Signal Efficiency0 0.1 0.2 0.3 0.4 0.5 0.6 0.7

Fake

rate

-310

-210

-110

= 1.75 TeVZ'

jet pT [600,800] M

smeared MC microjet radii 0.2smeared MC microjet radii 0.15

Using jet substructure - Oregon

Effect of microjet radii

21

Page 22: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

Signal Efficiency0 0.1 0.2 0.3 0.4 0.5 0.6

Fake

rate

-310

-210

-110

= 3 TeVZ'

jet pT [1000,2000] M

smeared MC microjet radii 0.2smeared MC microjet radii 0.15

Using jet substructure - Oregon

Effect of microjet radii

22

Page 23: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

Wrap up

η

-1

-0.5

0

0.5

1

φ

0.20.4

0.60.81

1.21.4

1.61.82

2.22.4

TH

igh

pT

Low

p

Using jet substructure - Oregon

Energy resolution might very well be a dominating factor on the actual performance of Shower Deconstruction. The further down we go in transverse momentum the more we face this downfalls. 20 GeV seems to be a good benchmark to cut on the microjet’s momentum. A ~ 4% in energy uncertainty does not seem to be a deal breaker. At the Terascale resolving the W->qq system indicates the need of a finer description of the microjets. Could it be easier to adapt the taggers rather than push the limits of ATLAS calorimetry ? Can we reconstruct with enough accuracy the microjets with the ATLAS detector ? How would pileup, in particular additional pileup microjets affect the performance ?

23

Page 24: Nicolas Gutierrez - University of Oregonpages.uoregon.edu/soper/TeraJets2013/TeraJets2013... · Using jet substructure - Oregon 2 Jet substructure techniques in ATLAS Substructure

The team

Using jet substructure - Oregon 24

Prof.  Tony  Doyle   Dr.  James  Ferrando   Dr.  Deepak  Kar  

Growing  ..  


Recommended