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tth, hbb with EventViews

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An Algorithm' is something which sequences tools. ... Adding soft 's back in to the jet helps. Using Kt alg. also helps.. Kt R-param=0.45. ... – PowerPoint PPT presentation

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Title: tth, hbb with EventViews

1
tth, (h?bb) with EventViews

Chris Collins-Tooth, Christian Shaw
28-Apr-2006

2
Introduction

tth (h?bb) physics overview.
Algorithms, Tools and EventViews.
EventView stages for tth (h?bb).
Some output (for 20k Mh130 GeV) MC Sample
Sim,Dig9.0.4
Reco10.0.4
Soon CSC only 2k events?!!
These are not even simulated yet.
Should we request more?
Difficulties.

3
The tth (h?bb) channel

Event trigger is a high Pt lepton.

4
The tth (h?bb) channel

Event trigger is a high Pt lepton.
Aim throw away most of the event leaving the
correct two b-jets, allowing Mh
reconstruction.

5
The tth (h?bb) channel

Event trigger is a high Pt lepton.
Aim throw away most of the event leaving the
correct two b-jets, allowing Mh
reconstruction.
Many combinatorical possibilities!
Must keep them in the list of possible Event
Views until we can judge which is the most
accurate combination (from comparison to truth,
t-mass reco.)

EV software tools suited to this..

6
Some Athena knowledge

An Algorithm is something which sequences
tools.
A Tool might correspond to one stage in your
analysis.
Normally, the first few tools will be inserters
Inserters take particles (or other info) from one
AOD event and insert them into an EventView. NB
Inserter order matters!
This EventView will then normally be passed to
your own tools, specialised for your analysis.

Algorithm
Inserters
myTool1
myTool2
EventView
Order of Inserters matters..
EventView
AOD
EventView
EventView
EventView
EventView
7
What do Tools and Algs look like?

Analysis Algs/Tools run in sequence.
You will notice EventView branches on the last
diagram.
Each tool can be made to spawn several new
EventViews.
The spawned EVs are then used as input to the
next tool.
The final collection of EVs can be looked at by a
new algorithm to decide upon the best EV.

theApp.TopAlg "EVMultipleOutputToolLooper/defa
ultEventView" theApp.TopAlg
"EVMultipleOutputToolLooper/analEventView" theAp
p.TopAlg "EVMultipleInputToolLooper/selectBest
EV" theApp.TopAlg "EVPointerToolLooper/dumpBe
stEventView" theApp.TopAlg "EVPointerToolLoop
er/CCTAAN" defaultEVAlg Algorithm(
"defaultEventView" ) analEVAlg Algorithm(
"analEventView" ) bestEVAlg Algorithm(
"selectBestEV" ) CCTAANAlg Algorithm( "CCTAAN"
) defaultEVAlg.EventViewTools
"EVElectronInserter", "EVMuonInserter",
"EVMuonInserter/bJetMuons",
"EVJetTagInserter/bjet", "EVJetTagInserter/lje
t, ... analEVAlg.EventViewTools
"EVTriggerLeptonFinder/trig",
"EVMuonJetAdder/mujetadder",
"EVnuSolutions", "EVSimpleCombo/WHad",
"EVttbar/ttbarCombos", "EVSimpleCombo/Hbb"
CCTAANAlg.EventViewTools
8
What do Tools and Algs look like?

Analysis Algs/Tools run in sequence.
You will notice EventView branches on the last
diagram.
Each tool can be made to spawn several new
EventViews.
The spawned EVs are then used as input to the
next tool.
The final collection of EVs can be looked at by a
new algorithm to decide upon the best EV.

Its like using a set of screwdrivers with round
ends!
Getting output found best to use
AthenaAwareNtuple.
To pass the best EV to the AANtuple, I had to
make a whole new class called PointerToolLooper!
PointerToolLooper takes in a pointer to an
existing EV.
Trying to re-record an EV in StoreGate which is
already there is not allowed!

10
Difficulties using EV in 11.0.3

Its like using a set of screwdrivers with round
ends!
Getting output found best to use
AthenaAwareNtuple.
To pass the best EV to the AANtuple, I had to
make a whole new class called PointerToolLooper!
PointerToolLooper takes in a pointer to an
existing EV.
Trying to re-record an EV in StoreGate which is
already there is not allowed!
The Tools I used were not by default set up to
give multiple EVs as output.. it requires a small
change.
Labelling and inserting the Truth Particles was
difficult
Inserting on overlap with other objects (needed)
causes labelling to go awry
Solution is to set overlap to VERY small for
truth particles, and use the OverlapNoCopyLabels
property.

11
tth (h?bb) tools...

For this channel, we need lots of items in the
EV

For this channel, we need lots of items in the
EV

For this channel, we need lots of items in the
EV

For this channel, we need lots of items in the
EV

defaultEVAlg.EventViewTools
"EVElectronInserter", "EVMuonInserter",
"EVMuonInserter/bJetMuons",
"EVJetTagInserter/bjet", "EVJetTagInserter/lje
t", "EVMissingEtUserData",
"EVEventInfoUserData", "EVTruthParticleInserte
r/truthSlim", "EVTruthLabeller/truthLabeller
analEVAlg.EventViewTools
"EVTriggerLeptonFinder/trig",
"EVMuonJetAdder/mujetadder",
"EVnuSolutions", "EVSimpleCombo/WHad",
"EVttbar/ttbarCombos", "EVSimpleCombo/Hbb"

Inserters
Put MissingEt into EV
Put MC truth info into EV
15
tth (h?bb) tools...

For this channel, we need lots of items in the
EV

For this channel, we need lots of items in the
EV

For this channel, we need lots of items in the
EV

For this channel, we need lots of items in the
EV

For this channel, we need lots of items in the
EV

For this channel, we need lots of items in the
EV

For this channel, we need lots of items in the
EV

When only a trigger electron..
Trigger electrons are
Ptgt25 GeV
no soft electrons
IsEM applied
Isolation no more than 15 GeV in cone 0.45
When theres only a trigger muon..
Trigger muons are
Ptgt 20 GeV
Muon track Chi2NdofCut lt 20
We intend to implement an isolation cut.

deltaR (electron only)
deltaR (muon only)
23
Electron or Muon?

When theres a trigger electron and some muons
which qualify as trigger candidates..
use the electron!!!
NB events with gt1 trigger electron candidate are
very rare.

24
b-jet Energy

Look at Ebjet/Ebquark
Adding soft ?s back in to the jet helps.
Using Kt alg. also helps..
Kt R-param0.45.
BEWARE theres a bug!
Value actually given in JobOpts0.2 (0.452).
Seems like a small effect, but b-jet
combinatorics sensitive to small energy shifts!

Add Muons
Cone
Kt
25
b-jet Energy

Look at Ebjet/Ebquark
Adding soft ?s back in to the jet helps.
Using Kt alg. also helps..
Kt R-param0.45.
BEWARE theres a bug!
Value actually given in JobOpts0.2 (0.452).
Seems like a small effect, but b-jet
combinatorics sensitive to small energy shifts!

Add Muons
Cone
better mean, more symmetric
Kt
26
Higgs Masses
Add Muons

Cone 0.7 simply not applicable to this
channel..too many jets!
Cone 0.4 not callibrated
Input Mh130 GeV.
Use Kt with ?s added.
Mass peaks
Cone4, no ?s 118 GeV
Kt4, with ?s 125 GeV

Cone
Kt
27
More detail...

If you want to see exactly how the tth (h?bb)
analysis is run, you can see my online log at

http//ppewww.ph.gla.ac.uk/chrisc/logs/eventview1
103-data1004.html
28
Finally

Backgrounds
We simulated gg-gtttbb with AcerMC
Other Backgrounds tbd with Atlfast.
Significances to follow soon havent had time
yet!

29
(No Transcript)
30
An EventView is....

A Container, much as an ElectronContainer.
It holds particles and objects of different
species.
It also holds user data, and user-created
particles.
It is one view of the event, and there may be
many views to choose from.. (explained later).

per event
AOD Electrons
EventView particle 1, labelElectron particle
2, labelMuon ... ... ...
AOD Muons
AOD bJetTags
AOD MissingEt data
AOD Truth info
31
Difficulties

Noticed BestEventView for first successful
event from any AOD file has many 0s for the
data.
The Tools I used were not by default set up to
give multiple EVs as output.. it requires a small
change.
Labelling and inserting the Truth Particles was
difficult
Inserting on overlap with other objects (needed)
causes labelling to go awry.
Solution is to set overlap to VERY small for
truth particles, and use the OverlapNoCopyLabels
property.