ATLAS

ATLAS-CONF-2012-137
とあるExotics会議のサマリーより
2
→　話はRUN2へ
新粒子発見の前兆とは •  最近の新粒子、成長の記録が取れている好例　：　Hà 4 leptons
3
新粒子発見の前兆とは •  最近の新粒子、成長の記録が取れている好例　：　Hà 4 leptons
4
2011年末の段階 •  discovery paper PLB 716(2012) 1 は10.7 fb-1 (4ℓ𝓁-channelのみで~3.5𝜎)
•  2011年末の段階(4.8 fb-1)では、既に兆候ははっきりとしていた、が。
ATLAS-CONF-2012-092
20
Data
ATLAS Preliminary
(*)
Background ZZ
(*)
Background Z+jets, tt
H ZZ
4l
Signal (m =125 GeV)
H
Ldt = 4.8 fb-1
Signal (m =150 GeV)
H
Signal (m =190 GeV)
s = 7 TeV
H
Syst.Unc.
15
0
25
Local p
Events/5 GeV
質量分布はかなり心眼が必要
102
10
10-2
10-3
5
ATLAS Preliminary
(*)
4l
H ZZ
s=7 TeV: Ldt =4.8 fb-1
s=8 TeV: Ldt =5.8 fb-1
1
10-1
10
Obs. combined
Exp. combined
Obs. 2011
Exp. 2011
Obs. 2012
Exp. 2012
1
2
3
10-4
4
0
-5
100
150
200
250
m4l [GeV]
10
110 120 130 140 150 160 170 180
mH [GeV]
教訓：
一. ぱっと見、ないからと言って諦めてはいけない
一. 統計処理するには十分なBG理解が必要
5
統計処理すると
結構見えてる（2011は青）
けれど2σちょっと
88TTeeVVのデータを見る上で •  始めから「ない」と思って見てはいけません
（Run-2の発見の兆候が見えてるかも知れません）
うが
ひょっとしたら、という穿った目で見てください
•  Higgsの例ほどきれいには分からないであろう理由
•  Exoticsは high energy tail の部分なのでBGのモデリング・評価
• 
の不定性が大きい
SM Higgsのような（ある程度）確実は信号モデルがない
→ ピーク or excess
→ ピークだとしても幅・大きさは隠れてる物理次第
•  このトークでは
•  スペクトルを見る、できれば統計情報も見る(p0分布はない)
•  BG評価、不定性の主な寄与は何か
6
Exotics strategy – 1
•  signature-based & model-independentな探索が望ましい
しかし余りにもphase-spaceが広すぎる
•  ある程度モデルをガイドにして ’hot’ な領域を重点的に攻める
•  Naturalness : 余剰次元、 Little Higgs, à (VLQ)
•  Dark Matter à mono-X 探索
•  Exotic Higgs decays / Higgs in Exotic decays
•  長寿命粒子 à hidden valley シナリオ等
•  また近年のBoosted Objects(Jet,W,Z ... )に対する技術的
発展も最大限活用していく
7
Exotics strategy – 2
•  Signature-basedに基づく探索（これで多くの現象論をカバーする）
•  探索結果に基づき→現象論毎の解釈
•  ここでは、単純な系→複雑な系へ、信号順に紹介
•  1 object
単純な系
•  Mono-X ; X=jet, photon, W/Z, etc
•  2 objects
•  Dilepton, Dijet, Photon+X, etc
•  more objects
•  Dijet + W/Z, DiBoson Resonance, etc
•  many objects
•  特別なケース
•  ttbar resonance
複雑な系
•  VLQ (vector like quarks)
•  Long-lived particle
8
Mono-X
/ Z / Jet / 𝛾
Large PT object + Large MET (recoil)
9
Mono-Jet (or Photon)
超過は見えていない
10
[Events/GeV]
dN/dp
T
s = 8 TeV
10
q/ g
G
1
Data / BG
10-1
1.5
1
0.5
300
400
500
600
700
800
900
1000 1100 1200
p jet1 [GeV]
jet pT [GeV]
T
断面積の上限
95% CL
ATLAS Preliminary
Expected limit
-1
Ldt=10.5 fb
1
Observed limit
s = 8 TeV
±1
exp
±2
exp
10-1
10-2
SR4
ppà KK massive graviton + jet (MDの下限値)
• GMSBモデル
ppà gravitino + squark/gluino (graivitino質量)
SR3
-1
Ldt=10.5fb
SR3
• Large Extra Dimensionモデル
102
SR2
•  Interpretation
data 2012
Total BG
Z(
) + jets
W ( l ) + jets
Z(
ll ) + jets
Dibosons
tt + single top
ADD n=2, MD=3 TeV
D5 M=80GeV, M*=670GeV
~
G +~
q/~
g, M~ ~=1TeV, M~ =10-4eV
ATLAS Preliminary
SR1
•  SR4ではかなりMCとずれてしまう
10.5 /fb
[pb]
• 
(SR1,2,3,4: xxx=120,220,350,500)
• 2nd jet pT>30GeVがいれば排除
BG
• Z(à𝜈𝜈)+jets
• W(àℓ𝓁𝜈)+jets
• Z/Wが系統誤差の主な要素
MCベースの評価
×A ×
•  Selection
• MET> xxx GeV, 1 jet pT> xxx GeV
ATLAS-CONF-2012-147
Mono-Jet (or Photon)
107
6
10
Z
CMS Preliminary
W l
s = 8 TeV
Phys.Rev.Lett. 110, 011802 (2013)
19.5 /fb
tt
t
-1
L dt = 19.5 fb
105
QCD
Z l+l
ADD M D= 2 TeV, = 3
DM = 0.9 TeV, M = 1 GeV
4
10
UNP dU=1.7,
103
U
Events / GeV
Events / 25 GeV
CMS EXO-12-048
Data 2011 ( s =7 TeV)
Z(
)+
W/Z+
W/Z+jet
top, +jet, multi-jet, diboson
Total background
ADD NLO, MD=1.0 TeV, n=2
WIMP, D5, m =10 GeV, M*=400 GeV
ATLAS
2
10
-1
L dt = 4.6 fb
10
1
= 2 TeV
Data
2
10
10-1
10
10-2
Data / MC
1
10-3
150
2
1.5
1
0.5
0
200
300
400
500
600
700
•  mono-jet (CMS)
11
800
900
1000
Emiss
[GeV]
T
•  8TeV 全統計
•  解析手法はATLASと同じ
•  超過は見えていない
200
250
300
350
400
450
500
miss
ET [GeV]
•  mono-photon (ATLAS)
•  7 TeV 4.6/fb
•  photon pT>150GeV要求
•  pT>30GeV jetがいれば除外
è Dark Matterに焼き直して制限付け
Mono-W/Z 探索 20.3 /fb
ATLAS-CONF-2013-073
•  Large radius jet
• capture two quarks from W/Z
• 内部subjetのbalanceをで評価
y
y = min(pT 1, pT 2 )ΔR / m jet
Events / 10 GeV
Phys.Rev.Lett. 112, 041802 (2014)
250
200
Data
Z(νν)+jet
W/Z(e/µ/τ)+jet
Top
Diboson
uncertainty
D5(u=d) x100
D5(u=-d) x1
ATLAS 20.3 fb-1 s = 8 TeV
> 350 GeV
SR: Emiss
T
ETmiss > 350GeV
150
100
•  Selection
• MET trigger > 150GeV
Events / 10 GeV
50
+ large radius jet (R=1.2, >250GeV,
m=50~120GeV, √y>0.4)
• MET>350,500GeV
•  BG
0
50
35
30
25
12
90
ETmiss > 500GeV
100
110
D5(u=d) x20
D5(u=-d) x0.2
120
100
120
20
15
10
• Z(à𝜈𝜈)+jets
5
• W(àℓ𝓁𝜈)+jets
• 主な系統誤差はCRの統計の少なさに 050
起因するもの
60
70
80
miss
SR: ET > 500 GeV
60
70
目立った超過は見えていない
80
90
110
m
[GeV]
jet
mJET [GeV]
Dark Matterへの制限現在のリミット(LUX)
•  仮定するinteractionの形式でspin
(in)dependenceが決まる
またenhanceする効果の有無
• 
10-36
D5(u=-d):obs
90% CL-36
10
D5(u=d):obs
D5:ATLAS 7TeV j(χχ)
10-38
10-38
D9:obs
D9: ATLAS 7TeV j(χχ)
spin-independent
spin-dependent
10-40
10-40
10-42
10-42
COUPP 2012
CoGeNT 2010
XENON100 2012
CDMS low-energy
-44
10
10-46
1
ATLAS 20.3 fb-1 s = 8 TeV
-44
10
10-463
10 1
10
mχ [GeV]
2
10
SIMPLE 2011
IceCube W+W
COUPP 2012
PICASSO 2012
10
IceCube bb
102
3
10
mχ [GeV]
mono-𝛾 Phys.Rev.Lett. 110, 011802 (2013)
13
10-29
ATLAS
s = 7 TeV, 4.7 fb , 90%CL
XENON100 2012
10-31
CDMSII low-energy
CoGeNT 2010
-33
10
D5: CDF qq
-35
10
j(
)
Dirac
D1: qq j( )
Dirac
D5: qq j( )
Dirac
D11: gg j( )
Dirac
-1 theory
-37
10
10-39
10-41
10-43
10-45
Spin-independent
1
ATLAS
-1
10
102
103
WIMP mass m [ GeV ]
WIMP-nucleon cross section [ cm2 ]
WIMP-Nucleon cross section [ cm2 ]
mono-jet (4.8/fb) JHEP 04 (2013) 075
-1
s = 7 TeV, 4.7 fb , 90%CL
SIMPLE 2011
Picasso 2012
D8: CDF qq j( )
Dirac
D8: CMS qq j( )
-35
10
10-36
Dirac
D8: qq j(
D9: qq j(
-1 theory
)Dirac
)Dirac
-37
10
10-38
10
-33
10
-34
10
-35
-Nucleon cross section [cm2]
χ-N cross-section [cm2]
mono-W/Z Phys.Rev.Lett. 112, 041802 (2014)
-36
10
-37
10
-38
10
-39
10
-40
10-40
10
1
10
2
ATLAS, D8, qq
ATLAS, D9, qq
ATLAS
10
10
WIMP mass m [ GeV ]
Dirac
(
)
Dirac
)
Dirac
(
(
)
Dirac
)
Dirac
-1
s =7 TeV, Ldt = 4.6 fb
-45
1
3
)
-43
10-44
10
j(
-1
10-41
10-42
Spin-dependent
Picasso
Dirac
10-39
10-41
SIMPLE
CDF, D8, qq
CMS (5 fb ), D8, qq
10
90% CL, Spin Independent
XENON100
CDMS
CDF, D5, qq j(
CoGeNT
CMS (5 fb-1), D5, qq
( )
Dirac
ATLAS, D5, qq
( )
Dirac
ATLAS, D1, qq
( )
90% CL, Spin Dependent
10
102
3
10 1
m [GeV]
10
102
3
10
m [GeV]
Two Objects
14
Dilepton channel
•  オーソドックスで簡素な解析
•  high-pT, 十分にisolateしたレプトンを要求
•  invariant massを組む、high mass tailではelectron channelが分解能良し
•  主なBGはZ/𝛾*ドレルヤン，NNLO MCで評価
•  80-110GeV領域でdataと規格化
ATLAS-CONF-2013-017
•  2TeVにおける、主な系統誤差はPDFの不定性
Data 2012
Z/ *
L dt = 20 fb
10
3
10
Observed / Expected
15
1
1
10-1
10-1
Z’ à ee 探索
200
300 400
Z’ à 𝜇𝜇 探索
10-2
0.6
100
Z’(2500 GeV)
3
10
1
0.8
1000
Max=1541GeV
2000 3000
mee [GeV]
Z’(1500 GeV)
10
10
1.2
tt
Diboson
s = 8 TeV
104
102
1.4
Z/ *
L dt = 20 fb
10
102
10-2
Data 2012
-1
5
Diboson
Z’(1500 GeV)
Z’(2500 GeV)
s = 8 TeV
104
ATLAS Preliminary
Z’ µµ Search
6
10
tt
Dijet & W+Jets
-1
5
Events
ATLAS Preliminary
Z’ ee Search
6
10
20 /fb
107
Observed / Expected
Events
107
1.4
1.2
1
0.8
0.6
100
200
300 400
1000
Max=1844GeV
2000 3000
mµµ [GeV]
Dilepton channel
Events
19.5 /fb
•  Spin-1 boson
• 
• 
ATLAS Preliminary
L dt = 19.5 fb-1
s = 8 TeV
104
103
102
GUT based Z’ : E6 model lightest Z’𝜒,Z’𝜓
Sequential SM (SSM) Z’ : SMと同じ結合を仮定
10
•  Spin-2 boson
• 
ATLAS-CONF-2013-066
1
10-1
RS graviton
10-2
obs. / exp.
•  Lepton universalityを破るようなBSMモデル
→ Di-tau 探索
ATLAS-CONF-2013-017
10-3
1.5
1
0.5
200 300
mtot
T (
ATLAS Preliminary
s = 8 TeV
Z’ ee
Expected limit
Expected ± 1
ATLAS Preliminary
s = 8 TeV
Z’ µµ
10-1
Expected ± 2
Observed limit
Z’SSM
10-2
1
B [pb]
B [pb]
1
Expected limit
Expected ± 2
10-4
Z’
Z’
10-3
L dt = 20 fb
10-4
-1
Z’ à ee 探索
16
L dt = 20 fb
-1
Z’ à 𝜇𝜇 探索
-5
-5
10
BG予想とよく一致
Observed limit
Z’SSM
Z’
10-3
0.5
1
1.5
2
2.5
3
3.5
MZ’ [TeV]
10
0.5
1
1.5
2
2000
1000
miss
,
E
)
[GeV]
T
had-vis
Expected ± 1
10-2
Z’
,
had-vis
back-to-backで反対方向にでる
di-tau（hadronic decay）事象
だけを選ぶ
20 /fb
10-1
Data 2012
Z/ *
Multijet
W /Z +jets
t t +single top
Diboson
Z’ (1750)
2.5
3
3.5
MZ’ [TeV]
106
Events / GeV
Events / GeV
Dilepton channel (CMSでは）
-1
CMS Preliminary, 8 TeV, 19.6 fb
105
DATA
+
γ /Z→e e-
104
tt, tW, WW, WZ, ZZ, ττ
jets (data)
103
2
10
17
106
CMS Preliminary, 8 TeV, 20.6 fb-1
105
DATA
+
γ /Z→µ µ-
104
tt, tW, WW, WZ, ZZ, ττ
jets (data)
103
2
10
10
10
1
1
-1
-1
10
10
10-2
10-2
10-3
10-3
10-4 70
CMS EXO-12-061
100
200
300 400
e & 𝜇 合わせると
2000
1000
m(ee) [GeV]
10-4 70
100
200
300 400
2000
1000
m(µ+µ-) [GeV]
M(Z’SSM) expected observed 参考 7TeV 5/fb では
ATLAS >2.96 TeV >2.96 TeV CMS >2.85 TeV >2.86 TeV ATLAS arXiv:1209.2535
obs (exp) 2.22 (2.25) TeV
Dijet channel
•  断面積大、最も高い質量領域へ感度
•  Inclusive dijet チャンネルでは、excited quarkベンチマークと
JESやLuminosity変動にrobust
105
13 /fb
ATLAS Preliminary
Data
Background
104
×
10
s = 8 TeV
L dt = 13.0 fb-1
ATLAS-CONF-2012-148
[pb]
Events
• 
• 
model independent bumpを探索
R=0.6 anti-kT jetsを捕まえて質量を組む
BGは滑らかな関数を用いてフィット
3
103
q* MC12
Observed 95% CL upper limit
Expected 95% CL upper limit
68% and 95% bands
102
10
102
10
Significance
1
18
2
1
highest pT = 2.34 TeV
highest M = 4.69 TeV
2000
3000
ATLAS Preliminary
L dt = 13.0 fb-1
s = 8 TeV
10-1
4000
10-2
0
10-3
-2
2000
3000
4000
Reconstructed mjj [GeV]
2000
3000
4000
5000
Mass [GeV]
Dijet channel (CMSでは)
10
19.6 /fb
1
Data
Fit
10-1
10
QCD MC
JES Uncertainty
-2
10-3
Cross Section × B × A (pb)
d!/dmjj (pb/GeV)
CMS EXO-12-059
W’ (1.9 TeV)
10-4
10-5
A / C (3.6 TeV)
(Data-Fit)/!Data
10-8
CMS Preliminary
102
s = 8 TeV, L = 19.6 fb-1
|η| < 2.5, |∆ η | < 1.3
10
jj
W’
Z’
1
10-1
10-3
CMS Preliminary
s = 8 TeV , L= 19.6 fb-1
|"| < 2.5 , |# " | < 1.3
jj
mjj > 890 GeV , Wide Jets
Observed 95% CL Upper Limit
Expected 95% CL Upper Limit
10-4
4
3
2
1
0
-1
-2
-3
-4
Expected Limit ± 1σ
-5
10
Expected Limit ± 2σ
-6
10
1000
1500
2000
2500
3000
3500
4000
4500
5000
5500
1000 1500 2000 2500 3000 3500 4000 4500 5000 5500
qq Resonance Mass (GeV)
Dijet Mass (GeV)
•  データポイントは5TeVを越えている
•  幾つか気になるbumpが存在　19
Axigluon/Coloron
E6 Diquark
10-2
10-6
10-7
103
M(q*) 95% CL luminosity expected observed ATLAS 8TeV 13.0 /5 > 3.70 TeV > 3.84 TeV CMS 8TeV 19.6 /5 > 3.75 TeV > 3.50 TeV Phys.Lett.B 728 (2014) 562
Events
Photon + X (=q,ℓ𝓁) channel
10
ATLAS
Data
Fit
104
•  Compositenessモデルではレプトンやクォークの
• 
5
s = 8 TeV
L dt = 20.3 fb-1
103
励起状態を予想
シングル生成を想定→電磁輻射崩壊
102
10
•  Selections
• ≥1 jet + ≥1 photon, pT > 125GeV
•  𝛾, j の角度に対する制限
Significance
1
2 0.5
1.5
1
1.5
Data
Fit
2.5
-2
2
q* (1.0 TeV, f = 1.0)
2.5
m γj
m
[TeV]
j [TeV]
Data
104
Background from Fit
q* (1.5 TeV, f = 1.0)
Events
103
• Dijet探索ではtrigger rescaleでinsensitiveな
2
0
0.5
•  BG
• Dijet同様の４パラメータfunctionをfitに用いる
1
Background from MC
102
q* (2.5 TeV, f = 0.5)
CMS Preliminary
低エネルギー領域0.5-1.0TeVを重点的に探索
10
s = 8 TeV
∫ Ldt=19.7 fb
-1
(Data-Fit)/ σData
1
20
q* → qγ
600
800 1000 1200 1400 1600 1800 2000 2200 2400 2600 2800 3000
600
800 1000 1200 1400 1600 1800 2000 2200 2400 2600 2800 3000
3
2
1
0
-1
-2
-3
1000
1500
2000
Mass Mγ jet (GeV)
M
[GeV]
γ jet
CMS EXO-13-003
2500
3000
m γj [TeV]
More Objects
21
Boosted objects
2.2
2
1.8
QCD, pile-up, underlying, etc
arXiv: 1306.4945
ATLAS Simulation
200
Pythia Z'→ tt, t → Wb
180
Δ R(q,q)
Δ R(W,b)
ΔR ≈ 2m / pT
4
3.5
160
1.4
140
1.2
120
1
0.8
100
80
1.5
0.6
60
1
0.4
40
0.2
20
pt [GeV]
T
0
200
Pythia Z' → tt, t → Wb
180
3
1.6
0
0 100 200 300 400 500 600 700 800 900
ATLAS Simulation
140
2.5
120
2
100
W q
q
b
80
60
40
0.5
0
0
160
20
100 200 300 400 500 600 700 800
0
pW [GeV]
T
•  LHCでは (√s ≫EW scale) Top, W, Z, HiggsなどLorentz boostされる
• 
• 
22
separationはpTに反比例して狭まる（→全体が1つのJetに包含される）
重い複数の‘中身’を持つJetの特徴
•  大質量を持つ
•  2,3体のhigh-pT sub componentがある
QCD radiation, パイルアップなどからのゴミを除いて（Glooming）、
中の構成要素だけを捕まえる（Tagging）
構成要素の質量<<全体質量, バランスも保持
arXiv: 1306.4945
performanceの一例
Arbitrary units
Boosted objects cont’d
•  Mass Drop Filtering algorithm (2 steps)
•  mass-drop & symmetry 過程： 2構成要素を生成 0.18
0.16
ATLAS Simulation
jet
C/A LCW jets, 600 ≤ p
T
0.14
Ungroomed Z→ qq
Ungroomed Dijets
Filtered Z→ qq
Filtered Dijets
0.12
0.1
0.08
< 800 GeV
two-prong decay
0.06
filtering過程：改めてsubjetを作る
•  Trimming, Pruning, HEPTopTaggerなど他のalgorithm
• 
23
0.02
3 hardest jets 以外は捨てる
も開発・用途に合わせて使用
現在は、
•  Boosted-W,Z用にtuningしたtagger
•  Boosted Hàbb用にtrack-jetを使ってbbをseparate
が開発・実用化されつつある
0
0
Arbitrary units
• 
0.04
0.14
50
100
150
200 250 300
Jet mass [GeV]
ATLAS Simulation
jet
0.12
0.1
0.08
C/A LCW jets, 600 ≤ pT < 800 GeV
Ungroomed Z'→ tt
Ungroomed Dijets
Trimmed Z'→ tt
Trimmed Dijets
three-prong decay
0.06
0.04
0.02
0
0
50
100
150
200 250 300
Jet mass [GeV]
pile-up依存性もきれいに抑制
100
ATLAS-CONF-2013-074
×103
L dt = 20.3 fb -1
s = 8 TeV
Data
W/Z + jets
Multijet
ATLAS Preliminary
W
l(e, µ) +
tt+single-t
(400)
W
2 jets
T
(290)
W
T
T(240) X10
T(160)
X10
Entries / 10 GeV
•  Models
• ED, LittleH, TCなどが候補
•  Selections
•  W/Zはleptonic崩壊
Entries / 10 GeV
Dijet + W/Z (VJJ signature)
WJJ
50
L dt = 20.3 fb -1
s = 8 TeV
10000
Data
W/Z + jets
ATLAS Preliminary
Z
l(e, µ) +
tt+single-t
2 jets
(400)
Z
T(240)
X10
(290)
Z
T(160)
X10
T
T
ZJJ
5000
•  pT(ℓ𝓁ℓ𝓁/ℓ𝓁𝜈)>50GeV, 2Jets pT>30GeV
•  115< mJJ< 300 GeV
•  Results
0
1.0
0.9
100
200
m jj [GeV]
300
400
1
LSTC
±
T
Z
±
T
assuming m =3/2*m +55 GeV
T
T
Observed 95% Upper Limit
0.8
Expected 95% Upper Limit
+1 Sigma Uncertainty
+2 Sigma Uncertainty
0.6
WJJ
100
200
300
400
100
200
300
400
1.1
1.0
0.9
0
mjj [GeV]
× BR [pb]
0
•  目立つ超過はなし
•  ZJJ のテイル部は単なる統計か
•  LSTC(ベンチマーク)への制限：省略
24
Data/Bkg
1.1
× BR [pb]
tuned at CR, pT(ℓ𝓁ℓ𝓁/ℓ𝓁𝜈)の形が
dataに合うように矯正
•  WJJ channel : ttbar MCから
0
0
Data/Bkg
•  BG
•  主に W/Z + jets
6
LSTC
0.4
± ,0
T
W
0,±
T
assuming m =3/2*m +55 GeV
T
T
Observed 95% Upper Limit
Expected 95% Upper Limit
ZJJ
+1 Sigma Uncertainty
4
+2 Sigma Uncertainty
L dt = 20.3 fb-1
s = 8 TeV
ATLAS Preliminary
-1
L dt = 20.3 fb
s = 8 TeV
ATLAS Preliminary
m jj [GeV]
mjj [GeV]
2
0.2
0
0
150
200
250
m jj [GeV]
300
M T [GeV]
150
200
250
m jj [GeV]
300
M T [GeV]
Di-Boson 共鳴 (WZ)
ED (Bulk RS): G*àWW,ZZ,HH
EGM : W’àWZ, Z’àZH
Composite Higgs, Walking TC, etc
•  VV à ( qq / lv / ll ) ⊗ ( qq / lv / ll ) = many
102
s = 8 TeV
10
Z+
ZZ
ll + jets
WZ
2012 Data
Total Error
ATLAS Preliminary
10-1
10-2
•  WZ à 3l + v mode
•  Selections
10-3
• 3 lepton pT>25 GeV, leptonは不可
• one pair satisfies “Zàll condition”
• MET>25 GeV
4th
•  BG
• SM WZが主：MCで評価、tail部の不定性
が大きい
(CRは実は余り合っていない)
10-40
200 400 600 800 1000 1200 1400 1600 1800 2000
MWZ [GeV]
Expected 95% CL Limit
±1
±2
W’ EGM Cross Section
1
Observed Limit
ATLAS Preliminary
s = 8 TeV
-1
Ldt = 13.0 fb
10-1
200
25
-1
Ldt = 13.0 fb
1
× BR(WZ) (pb)
• 
• 
• 
Events / 40 GeV
•  共鳴を作るモデル群
ATLAS-CONF-2013-015
400
600
800
1000 1200 1400 1600
W’ Mass [GeV]
Di-Boson 共鳴 (ZZ)
ZZ ) [pb]
ATLAS-CONF-2012-150
•  ll +qq mode
•  lepton pair = Zからの
G*) × BR( G*
(pp
800
1000 1200 1400 1600 1800 2000
104
ATLAS Preliminary
Merged Selection
Data
Background
s = 8 TeV
L dt = 7.2 fb-1
10
resolved
2 3×102
0
4× 102
1
10
3
-2
3×102
m(lljj )
103
2× 10
3
Significance
Significance
26
600
102
1
今後Boosted W/Z tagging が確立されると、一気に感度が上がる領域 10
103
102
Smooth Functionで
fitして評価
-1
s = 8 TeV , Ldt = 7.2 fb
-1
combined
s = 8 TeV
L dt = 7.2 fb-1
4
ATLAS Preliminary
mG* [GeV]
Data
Background
ATLAS Preliminary
Resolved Selection
10
Expected 95% Upper Limit
±1
±2
10-2 400
Events
Events
主なBGは
Z+jets, SM Diboson
Observed 95% Upper Limit
1
崩壊であることを満たす
•  まだBoosted Z tagは
使っていない
•  pT(ll)=200GeVを境に、2jet resolve (以下）か
1jet merge (以上）のSRを設定、それぞれ
mjj or mjがZ mass付近にいることを要求
106
RS Graviton, /mPlanck= 1.0
2×103
m(lljj) [GeV]
1
0
-1
merged
6× 102
6×102
10
3
m(llj )10
3
2× 10
3
2×103
m(llj) [GeV]
特別なケース
27
Boosted
ttbar Resonance Searches
•  多くのモデルで重く、topとの結合が強い粒子を予言
•  ATLASのベンチマーク
• 
• 
b-tag要求
1つのlarge jet (R=1.0)と
してtopを構成する
leptophobic top color model : Z’ 幅が細い1.2%
RS KK-gluon : 幅 15.3%
•  ttbar à leptonic崩壊＋hadronic崩壊
•  不変質量再構成分布にbumpを探す
•  再構成に2方式
• 
Fraction of events / 100 GeV
Fraction of events / 50 GeV
ATLAS Preliminary
0.25
Simulation, s=8TeV
Resolved
0.2
Z’ (0.5 TeV)
Z’ (1.0 TeV)
Z’ (1.5 TeV)
Z’ (2.0 TeV)
0.15
0.1
0.05
28
１つ以上b-tag
Boosted (pT>300GeV) / Resolved (それ以外)
Resolved
0
0
Resolved
2-3のsmall jet (R=0.4)
としてtopを構成する
Boosted
0.3
ここでは
Trimmingという
手法が使われる
ATLAS Preliminary
Simulation, s=8TeV
Boosted
0.25
Z’ (1.0 TeV)
Z’ (1.5 TeV)
Z’ (2.0 TeV)
Z’ (3.0 TeV)
0.2
0.15
ATLAS-CONF-2013-052
0.1
0.05
0.5
1
1.5
2
2.5
3
3.5
mreco
[TeV]
tt
0
0
0.5
1
1.5
2
2.5
3
3.5
mreco
[TeV]
tt
6
10
Data
tt
Multi-jets
5 × Z’ (1.5 TeV)
5 × g (2.0 TeV)
KK
s = 8 TeV
104
Z’
3
10
102
Data/Bkg
1.5
1
0.5
0
0.5
1
1.5
2
2.5
3
10
L dt = 14.3 fb-1
102
ATLAS Preliminary
10
3.5
10-1
10-2
0
0.5
1
1.5
2
2.5
3
mreco
tt
29
Obs. 95% CL upper limit
Exp. 95% CL upper limit
Exp. 1 uncertainty
Exp. 2 uncertainty
Leptophobic Z’ (LO x 1.3)
1
10
1
s = 8 TeV
3
W+jets
Other Backgrounds
105
tt) [pb]
108 ATLAS Preliminary
-1
107
L dt = 14.2 fb
ATLAS-CONF-2013-052
× BR(Z’
Events / TeV
ttbar Resonance Searches
3.5
[TeV]
0.5
1
•  BG
•  SM ttbar, W+jetsが主
•  系統誤差の主な寄与はJESから
•  若干over estimate気味だが、不定性の範囲
•  0.5-1.8 TeV Z’-like resonance 排除
•  ‘Boosted’の進展 → m=2〜3TeVは十分にいける
1.5
2
2.5
3
Z’ mass [TeV]
Vector-like quarks (VLQ)
•  Top quarkのパートナー(T)がヒッグス発散を抑制
•  VLQ(T,B)の対生成(QCD), シングル生成
（mixing with quarks）を探索
•  FCNC崩壊（TàtZ）は抑制されない
•  BR (TàWb, TàZt, TàHt) はモデル依存性大
SUSYの代わりに、Higgs質量の発散を抑え
てくれる、”yet もう一つ”の案
３つのチャンネルを独立にみる
Branching Ratio
30
1
(T,B) or
SU(2) Singlet
0.8
(X,T) Doublet
T → Wb
T → Wb
T → Zt
T → Ht
T → Zt
T → Ht
Branching Ratio
Bからの崩壊比
Tからの崩壊比
1
SU(2) Singlet
0.8
0.6
0.6
0.4
0.4
0.2
0.2
0
0
300
400
500
600
700
800
900
1000
mT [GeV]
300
(B,Y) Doublet
B → Wt
B → Wt
B → Zb
B → Hb
B → Zb
B → Hb
400
500
600
700
(T,B) Doublet
B → Wt
800
900
1000
mB [GeV]
VLQ (TWb)
•  崩壊モードのうち、Top decayと質量以外同じ
•  手法は4th quark探索と同様
•  ここではT対生成を想定
•  Selection
TT (600) Chiral
TT (600) Singlet
tt
Non-t t
Total BG uncert.
120
100
60
赤領域の下辺が
total BG予想
40
20
0
1.5
1
0.5
mreco [GeV]
102
ATLAS Preliminary
Theory (approx. NNLO prediction ±1 )
95% CL expected limit
Events / 150 GeV
TT) [pb]
Data ( s = 8 TeV)
loose
系統誤差の主な原因
• 大きな逸脱は見えていない
ATLAS Preliminary
L dt = 14.3 fb -1
0 100 200 300 400 500 600 700 800 900 1000
Data ( s = 8 TeV)
45
40
35
30
95% CL expected limit ±1
10
(pp
•  BG
• 主に ttbar :
140
80
Data / BG
•  1 lepton (e/m) + ≥ 4 jets + ≥ 1 b-tag
•  b-jetとjetsの角度要求（ttbar抑制）
•  HT(jets+leptons+MET)>800GeV (loose)
Events / 150 GeV
ATLAS-CONF-2013-060
95% CL observed limit
1
tt
Non-t t
Total BG uncert.
tight
25
95% CL expected limit ±2
TT
TT (600) Chiral
TT (600) Singlet
更にbjets
ATLAS pt1>160GeV,
Preliminary
pt2>80GeV要求
L dt = 14.3 fb -1
20
Wb+X
15
10
10-1
s = 8 TeV
-1
Ldt = 14.3 fb
300
31
400
500
SU(2) singlet
600
700
800
900
mT [GeV]
Data / BG
10-2
5
0
3
2
1
0 100 200 300 400 500 600 700 800 900 1000
mreco [GeV]
VLQ (TàHtàbbt, TàZt)
•  それぞれ、T→Wbと相補的な関係
•  Selection
(TàHtàbbt)
(TàZt)
•  1 lepton (e/m) + ≥ 6 jets
•  3 SR : 2,3, ≥ 4 b-tagged jets
2 lepton (e/m) + 2 b-jets
pT(Z)>150GeV, HT(jets)>600GeV
100
80
60
ATLAS Preliminary
L dt = 14.3 fb -1
e+µ
6 jets, 4 b-tags
Data ( s = 8 TeV)
t’t’ (600)
t t +light jets
t t +HF jets
ttH
ttV
W+jets
Z+jets
Diboson
Single top
Multijet
Tot bkg unc.
ATLAS-CONF-2013-056
Entries / 150 GeV
Events / 100 GeV
ATLAS-CONF-2013-018
60
ATLAS
Preliminary
50
∫Ldt = 14.3 fb
data 2012
-1
Z+light
Z+bottom
s = 8 TeV
ee + µ µ
tt
Other bkg
B B (600 GeV)
T T (600 GeV)
Uncertainty
40
1 b-tag
30
40
≥4 b-tag
20
20
0
1.5
1
0.5
0
200 400 600 800 1000 1200 1400 1600 1800 2000
HT [GeV]
32
boosted Hàbbを捉えられるか今後の課題
Data/bkg
Data / MC
10
0
1.5
200
400
600
800
1000
1200
1400
m(Zb) [GeV]
1
0.5
0
200
400
600
800
1000
1200
1400
m(Zb) [GeV]
VLQのまとめ
Ht)
mQを固定、対生成に対してBrを変えて、同じ解析手法を行う
1
1
Fo
0.8
mT = 350 GeV
rb
id
BR(T
de
0.6
bid
de
n
0.6
Fo
rb
idd
en
0.8
0.6
0.4
0.4
0.4
0.2
0.2
0.2
mT = 450 GeV
Status: Lepton-Photon 2013
-1
s = 8 TeV,
L dt = 14.3 fb
95% CL exp. excl.
95% CL obs. excl.
Ht+X
[ATLAS-CONF-2013-018 ]
Same-Sign [ ATLAS-CONF-2013-051]
0
0
0.2
0.4
0.6
0.8
1
1
0
0
0.2
0.4
0.6
0.8
1
1
Fo
0.8
mT = 500 GeV
rb
id
de
0.6
0
0.2
0.4
0.6
0.8
1
1
mT = 550 GeV
Fo
r
bid
0.8
n
0
0.6
0.6
mT = 600 GeV
0.4
0.2
0.2
0.2
0.2
0.4
0.6
0.8
1
1
0
0
0.2
0.4
0.6
0.8
1
1
Fo
0.8
rb
id
mT = 700 GeV
de
0.6
0
0.2
0.4
0.6
0.8
1
1
mT = 750 GeV
Fo
r
bid
0.8
n
0
0.6
0
Fo
rb
idd
en
0.6
mT = 800 GeV
0.4
0.4
0.2
0.2
0.2
0.2
0.2
0.4
0.6
0.8
1
0
0
0.2
0.4
0.6
0.8
1
0
0
0.2
0.4
0.6
0.8
1
0
0.2
0.4
mT = 850 GeV
Fo
rb
idd
en
0.6
0.4
0
en
0.8
0.4
0
idd
1
0.8
de
n
SU(2) singlet
mT = 650 GeV
0.6
0.4
0.2
[ATLAS-CONF-2013-060 ]
Fo
rb
0.8
0.4
0
[ATLAS-CONF-2013-056 ]
Wb+X
1
Fo
rb
idd
en
0.8
de
n
Zb/t+X
SU(2) (T,B) doub.
0.4
0
33
Fo
r
0.8
n
ATLAS Preliminary
1
mT = 400 GeV
0.6
0.8
1
0
0
0.2
BR(T
0.4
0.6
Wb)
0.8
1
Long-Lived Particles (Non-SUSY)
•  長生き後 2-jets decayするような中性粒子
•  ベンチマークはHidden Valley Model
•  pp→H0→2X0, X0→q-qbar
• 
• 
X0（hidden sector粒子）が長生き
ATLASは7TeVでq-qbarの代わりに𝜇-pair
CMSが8TeV full statでUpdateした
CMS EXO-12-038
34
Long-Lived Particles (Non-SUSY)
Secondary Vertex
candidate event
35
まとめ
Large ED (ADD) : monojet + E T ,miss
Large ED (ADD) : monophoton + E T ,miss
Large ED (ADD) : diphoton & dilepton, m / ll
UED : diphoton + E T ,miss
S1/Z 2 ED : dilepton, mll
RS1 : dilepton, mll
RS1 : WW resonance, mT ,l l
Bulk RS : ZZ resonance, mlljj
RS g
tt (BR=0.925) : t t
l+jets, m
KK
tt
ADD BH ( M TH /M D =3) : SS dimuon, N ch. part.
ADD BH ( M TH /M D =3) : leptons + jets, p
T
Quantum black hole : dijet, F (mjj )
qqqq contact interaction : (m )
jj
qqll CI : ee & µµ, m
ll
uutt CI : SS dilepton + jets + E T ,miss
Z’ (SSM) : mee/ µ µ
Z’ (SSM) : m
Z’ (leptophobic topcolor) : tt
l+jets, mtt
W’ (SSM) : mT,e/µ
W’ ( tq, g =1) : mtq
R
W’R ( tb, LRSM) : m
tb
Scalar LQ pair ( =1) : kin. vars. in eejj, e jj
Scalar LQ pair ( =1) : kin. vars. in µµjj, µ jj
Scalar LQ pair ( =1) : kin. vars. in jj, jj
th
4 generation : t’t’ WbWb
4th generation : b’b’ SS dilepton + jets + E
ATLAS Exotics Searches* - 95% CL Lower Limits (Status: May 2013)
-1
M D ( =2)
Extra dimensions
•  8TeVの解析ではオーソドックスなチャンネルをしっかりと
L =4.7 fb , 7 TeV [1210.4491]
4.37 TeV
-1
1.93 TeV
L =4.6 fb , 7 TeV [1209.4625]
M D ( =2)
ATLAS
4.18 TeV M S (HLZ =3, NLO)
Preliminary
Compact. scale R -1
-1
4.71 TeV MKK ~ R
2.47 TeV Graviton mass (k / M Pl = 0.1)
1.23 TeV Graviton mass (k / M Pl = 0.1)
Ldt = ( 1 - 20) fb-1
850 GeV Graviton mass (k / M Pl = 1.0)
2.07 TeV g mass
KK
s = 7, 8 TeV
1.25 TeV M D ( =6)
1.5 TeV M D ( =6)
4.11 TeV M D ( =6)
-1
L =4.7 fb , 7 TeV [1211.1150]
-1
1.40 TeV
L =4.8 fb , 7 TeV [1209.0753]
V’
CI
抑えながら、同時に新しい領域を次々と開拓している
•  これまでのところ明らかな超過等はなく、制限付けが
粛々と行われてきている
•  各チャンネルの個性を見ていくと、全てSM通りということもない
•  統計が足りない、BGの理解が不十分で不定性が大
•  1.5~2.0σ の統計的逸脱はいる
•  今日お見せしたのは、極一握りの結果に過ぎない
•  是非、興味あるチャンネルをコントロールplotからじっくり確認し
て欲しい　-1
L =5.0 fb , 7 TeV [1209.2535]
-1
L =20 fb , 8 TeV [ATLAS-CONF-2013-017]
-1
L =4.7 fb , 7 TeV [1208.2880]
-1
L =7.2 fb , 8 TeV [ATLAS-CONF-2012-150]
-1
L =4.7 fb , 7 TeV [1305.2756]
-1
L =1.3 fb , 7 TeV [1111.0080]
-1
L =1.0 fb , 7 TeV [1204.4646]
-1
L =4.7 fb , 7 TeV [1210.1718]
-1
7.6 TeV
L =4.8 fb , 7 TeV [1210.1718]
-1
13.9 TeV
L =5.0 fb , 7 TeV [1211.1150]
-1
3.3 TeV
L =14.3 fb , 8 TeV [ATLAS-CONF-2013-051]
-1
L =20 fb , 8 TeV [ATLAS-CONF-2013-017]
2.86 TeV
Z’ mass
1.8 TeV Z’ mass
2.55 TeV W’ mass
-1
1.4 TeV
L =4.7 fb , 7 TeV [1210.6604]
-1
L =14.3 fb , 8 TeV [ATLAS-CONF-2013-052]
-1
L =4.7 fb , 7 TeV [1209.4446]
-1
L =4.7 fb , 7 TeV [1209.6593]
(constructive int.)
(C=1)
Z’ mass
430 GeV
W’ mass
-1
L =1.0 fb , 7 TeV [1112.4828]
660 GeV
Other
ferm.
Excit.
New
quarks
LQ
1.84 TeV W’ mass
st
1 gen. LQ mass
nd
-1
L =1.0 fb , 7 TeV [1203.3172]
685 GeV 2 gen. LQ mass
rd
-1
L =4.7 fb , 7 TeV [1303.0526]
534 GeV 3 gen. LQ mass
-1
L =4.7 fb , 7 TeV [1210.5468]
656 GeV t’ mass
-1
L =14.3 fb , 8 TeV [ATLAS-CONF-2013-051]
720 GeV b’ mass
T ,miss
790 GeV T mass (isospin doublet)
Vector-like quark : TT Ht+X L =14.3 fb-1, 8 TeV [ATLAS-CONF-2013-018]
Vector-like quark : CC,ml q L =4.6 fb-1, 7 TeV [ATLAS-CONF-2012-137]
1.12 TeV VLQ mass (charge -1/3, coupling qQ = /mQ)
-1
Excited quarks : -jet resonance, m
L =2.1 fb , 7 TeV [1112.3580]
2.46 TeV q* mass
jet
Excited quarks : dijet resonance, mjj L =13.0 fb-1, 8 TeV [ATLAS-CONF-2012-148]
3.84 TeV q* mass
Excited b quark : W-t resonance,mWt L =4.7 fb-1, 7 TeV [1301.1583]
870 GeV b* mass (left-handed coupling)
-1
Excited leptons : l- resonance, m
L =13.0 fb , 8 TeV [ATLAS-CONF-2012-146]
2.2 TeV l* mass ( = m(l*))
l
-1
Techni-hadrons (LSTC) : dilepton,mee/ µ µ L =5.0 fb , 7 TeV [1209.2535]
/
mass ( m( T/ T) - m( T) = MW )
850 GeV
T
T
-1
Techni-hadrons (LSTC) : WZ resonance (l ll), m
L =13.0 fb , 8 TeV [ATLAS-CONF-2013-015]
mass ( m( T) = m( T) + mW , m(aT) = 1.1 m( T))
920 GeV
WZ
T
1.5 TeV N mass (m(W ) = 2 TeV)
Major. neutr. (LRSM, no mixing) : 2-lep + jets L =2.1 fb-1, 7 TeV [1203.5420]
R
245 GeV
N± mass (|Ve | = 0.055, |Vµ | = 0.063, |V | = 0)
Heavy lepton N± (type III seesaw) : Z-l resonance, mZl L =5.8 fb-1, 8 TeV [ATLAS-CONF-2013-019]
±±
±±
±
±
HL (DY prod., BR(HL ll)=1) : SS ee (µµ), m L =4.7 fb-1, 7 TeV [1210.5070]
409 GeV HL mass (limit at 398 GeV for µ µ )
ll
Color octet scalar : dijet resonance, mjj L =4.8 fb-1, 7 TeV [1210.1718]
1.86 TeV Scalar resonance mass
490 GeV mass (|q| = 4e)
Multi-charged particles (DY prod.) : highly ionizing tracks L =4.4 fb-1, 7 TeV [1301.5272]
-1
862 GeV mass
Magnetic monopoles (DY prod.) : highly ionizing tracks L =2.0 fb , 7 TeV [1207.6411]
-1
L =14.3 fb , 8 TeV [ATLAS-CONF-2013-050]
10-1
36
*Only a selection of the available mass limits on new states or phenomena shown
1
10
102
Mass scale [TeV]
BACKUP SLIDES
37
38
black hole searches
• 
ATLAS
•  [arXiv:1311.2006]
Search for Quantum black holes in high-invariant mass lepton+ jet final states
•  [PRD88, 072001(2013)]
Search for microscopic black holes in a like-sign dimuon final state using large track multiplicity
•  CMS
•  [JHEP97(2013)178]
Search for microscopic black holes with energetic multi-particle final states
39
新粒子発見の前兆とは •  最近の新粒子、成長の記録が取れている好例　：　Hà 𝛾𝛾
40
2011年末の段階 •  discovery paper PLB 716(2012) 1 は10.7 fb-1 (𝛾𝛾-channelのみで4.?𝜎)
•  2011年末の段階(4.8fb-1)では、既に兆候ははっきりとしていた、が。
Events / GeV
質量分布はかなり心眼が必要
0
10
Local p
ATLAS-CONF-2012-091
ATLAS Preliminary
1
1
10-1
2
1000
10-2
Selected diphoton sample
900
800
Data 2011
Background model
SM Higgs boson m = 126.5 GeV (MC)
10-3
-1
-5
H
700
s = 7 TeV,
600
Ldt = 4.8 fb
SM H
10-4
Data 2012, s= 8 TeV, Ldt = 5.9 fb-1
4
10
Observed p 2011+2012 (with ESS)
0
Observed p 2011 (with ESS)
0
-6
ATLAS Preliminary
500
3
Data 2011, s= 7 TeV, Ldt = 4.8 fb-1
10
Observed p 2012 (with ESS)
0
統計処理すると
明らか（2011は青）
Observed p 2011+2012
0
Expected p 2011+2012
0
Observed p 2011
0
Epected p 2011
0
Observed p 2012
0
Expected p 2012
5
0
-7
400
10 110
115
120
125
130
135
140
300
145
150
mH [GeV]
Local p
0
200
Data - Bkg
100
0
50
0
-50
100
110
120
130
140
150
160
m [GeV]
教訓：
一. ぱっと見、ないからと言って諦めてはいけない
一. 統計処理するには十分なBG理解が必要
41
s = 7 TeV (2011), Ldt = 4.8 fb
10 ATLAS
s = 8 TeV (2012), Ldt = 5.9 fb
1
1
10-1
2
10-2
3
10-3 07/11 EPS Prel.
Observed
-4
10
Expected
4
-5 12/11 CERN Prel.
10
Observed
Expected
10-6
5
-7 Spring 2012 PRD
10
Observed
Expected
10-8
07/12
CERN
Prel.
PLB 07/12
6
10-9
Observed
Observed
Expected
Expected
-10
10
110 115 120 125 130 135 140 145 150
-1
-1
N.B. これは全チャンネル
~2𝜎=2011/7は1fb-1
Phys. Lett. B 716(2012)1
mH [GeV]

Download Report