HCAL performance studies and
software integration
FCC-hh detector meeting February 2017
C. Neubüser, A. Henriques, C. Helsens,
J. Faltova, A. Zaborowska, M. Aleksa
CERN
08.02.2017
08.02.2017
Coralie Neubüser
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FCC HCAL barrel
based on ATLAS TileCal
Design until FCC week 2016:
•
12m bore solenoid (6T)
•
Active HCAL depth ≈2m
•
10𝜆 + 2𝜆 ECAL ≈ 12𝜆
HCAL modules
Current baseline:
•
10m bore solenoid (4T)
•
Active HCAL depth 1.8m within (2.85 − 4.65)𝑚
•
9.0𝜆 + 2𝜆 ECAL = 11𝜆
08.02.2017
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Old FCC-hh detector design
Study of impact of containment by
increasing HCAL depth
à 12𝜆 favourable
master
Single pion resolution
2016 JINST 11 P09012
08.02.2017
Coralie Neubüser
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New FCC-hh HCAL requirements
Current baseline:
•
10m bore solenoid (4T)
•
Active HCAL depth 1.8m
•
9.0𝜆 + 2𝜆 ECAL = 11𝜆
Idea
Increase of #interaction lengths by
increasing Fe/Sci ratio from 4.7 to 6
(master thickness from 5 to 7mm)
Fe/Sci ratio
4.7
6.0
𝛌eff
20.6cm
19.8cm
Active depth
(𝜂 = 0)
180cm
180cm
8.7
9.1
#𝝀 (𝜂 = 0)
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•
from (2.5 - 6)m to (3.6 - 5.4)m
from 35 to 22 layers
Master thickness:
•
from 5 to 7mm
à sequence from 18 to 22mm
3 mm
master
air
tile
air
•
5/7mm
Radius:
•
spacer
Changes to earlier study:
4 mm
•
master
•
FTFP_BERT physics list
No ECAL
•
5/7 mm
HCAL Geant4 standalone
10cm
20˚
•
Fe/Sci ratio
𝛌eff
4.7
20.6cm
Effective depth
180cm * arccos(20˚)
𝒆𝒇𝒇𝒆𝒄𝒕𝒊𝒗𝒆#𝝀
9.3
10,20,100 and 2000GeV single 𝜋’s
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Validation
4.7
Master th.
5mm
Scintillator th.
3mm
Sampling
fraction
2.5%
20.6cm
Effective depth
174.2cm * 1.06
𝒆𝒇𝒇𝒆𝒄𝒕𝒊𝒗𝒆#𝝀
9.0
42.6%
⊕ 3.9%
√𝐸
𝛔?
𝐄
0.14
5mm master, 9.0λ HCAL
0.12
rec
𝛌eff
Single pion resolution
2016 JINST 11 P09012
σE / 〈 Erec〉
Fe/Sci ratio
Containment of hadron
showers in FCChh paper
Carlos
JINST(5mm) 9.0λ
0.1
0.08
0.06
Close to perfect
agreement
0.04
0.02
10
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E [GeV]
102
6
Impact of larger Fe/Sci ratio
1.
2.
à
Decreased sampling fraction
2.5% à 1.8%
Increased #interaction lengths
9.3 à 9.7
Check of impact of increased #𝜆E
on linearity:
•
Leakage is visible > 100GeV
beam
(〈Erec 〉-Ebeam)/E
By increasing Fe/Sci ratio
0.05
0
−0.05
−0.1
0.14
σErec/ 〈 Erec〉
•
0.1
102
0.12
103
104
Ebeam [GeV]
5mm master (9.7#λ)
5mm master (9.3#λ)
0.1
5mm master (9.0#λ)
0.08
0.06
0.04
0.02
The non-linearity of pion response
affected by e/h > 1 and leakage
08.02.2017
0
𝐸FGH = 1?𝛼 J 𝐸KLM
𝛼 = 0.023
102
Coralie Neubüser
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104
E [GeV]
7
Impact of larger Fe/Sci ratio
1.
2.
Decreased sampling fraction
2.5% à 1.8%
Increased #interaction lengths
9.3 à 9.7
beam
By increasing Fe/Sci ratio
(〈Erec 〉-Ebeam)/E
•
0.1
0.05
0
−0.05
−0.1
à
Impact of decreased sampling
fraction:
•
Worse resolution and linearity
σErec/ 〈 Erec〉
0.14
102
0.12
103
104
Ebeam [GeV]
5mm master (9.7#λ)
5mm master (9.3#λ)
0.1
7mm master (9.7#λ)
0.08
0.06
𝐸FGH = 1?𝛼 J 𝐸KLM
0.02 𝛼 = 0.023(5𝑚𝑚)
𝛼 = 0.018(7𝑚𝑚)
0.04
Larger non-linearity for higher Fe/Sci ratio,
surprising since e/h~1
08.02.2017
0
102
Coralie Neubüser
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104
E [GeV]
8
Summary electrons
6
Master th.
5mm
7mm
Scintillator th.
3mm
3mm
Sampling
fraction
2.5%
1.8%
0.05
0
−0.05
−0.1
0.14
27.8%
√𝐸
⊕ 0.6%
36.3%
√𝐸
⊕ 2.4%
σErec/ 〈 Erec〉
𝛔?
𝐄
0.1
beam
4.7
(〈Erec 〉-Ebeam)/E
Fe/Sci ratio
102
103 E
[GeV]
beam
5mm master
0.12
7mm master
0.1
0.08
• ATLAS TileCal electron
OP.Q%
resolution √R ⊕ 2.8%
à increased 𝜂 dependence due to worse
sampling frequency
à investigation on-going!
08.02.2017
0.06
0.04
0.02
0
Coralie Neubüser
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103
E [GeV]
9
Summary pions
Fe/Sci ratio
4.7
4.7
4.7
6
Master th.
5mm
5mm
5mm
7mm
Scintillator th.
3mm
3mm
3mm
3mm
Sampling
fraction
2.5%
2.5%
2.5%
1.8%
𝛌eff
20.6cm
20.6cm
20.6cm
19.8cm
Effective
depth
174cm *
1.06
180cm *
1.06
189cm *
1.06
180cm *
1.06
#𝝀
9.0
42.6%
43.5%
9.7
43.6%
9.7
44.1%
√𝐸
⊕ 3.9%
√𝐸
⊕ 3.3%
√𝐸
⊕ 3.0%
√𝐸
⊕ 5.0%
𝛔?
𝐄
𝒆?
𝒉
9.3
1.2
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Summary
à Keep as baseline the
original design with Fe/Sci ratio
of 4.7 (as in ATLAS)
08.02.2017
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190cm
-
10.5
10
9.5
9
8.5
8
7.5
7
6.5
6
5.5
#λn
•
Larger sampling fraction preferred over
larger #𝜆E
Profit of smaller Fe/Sci ratio
questionable (study postponed)
180cm
8
170cm
6
4
2
1
2
σE/〈E〉 of 2TeV π [%]
•
3
4
Coralie Neubüser
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6
7
8
Fe/Sci ratio
11
0
HCAL geometry in FCCSW
“subWedge”
•
•
Check of geometry
implementation
HCalBarrel_geo.cpp – done
Birks law for the scintillator
included
08.02.2017
Tile
Steel absorber
Coralie Neubüser
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Validation of HCAL in FCCSW
•
•
larger response
slight degradation of resolution
à Under investigation! electrons, 𝜂
dependence, bugs in the code…
0.1
beam
(〈Erec〉-Ebeam)/E
First glimpse into single pions
revealed
0.05
0
−0.05
−0.1
0.14
σErec/ 〈 Erec〉
•
102
0.12
103
104
Ebeam [GeV]
Standalone Fe/Sci 4.7 (9.3#
λ)
FCCSW Fe/Sci 4.7 (9.3#λ)
0.1
𝐸KLM
2.8%
𝐸KLM
=
2.3%
0.08
𝐸FGH =
0.06
𝐸FGH
0.04
0.02
0
08.02.2017
work in progress
102
Coralie Neubüser
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104
E [GeV]
13
Software for calorimeter system
Goal is a combined reconstruction
•
Reconstruction tools (generalized for
different technologies/geometries)
•
•
•
•
Merging of energy deposits into cells
Position of cells
Noise (simple)
Sliding window algorithm (single CAL)
✔
✔
✔
✔
work in progress
08.02.2017
Coralie Neubüser
14
Software for calorimeter system
Ongoing
•
Sliding window for E + HCAL
•
Contact with LC ECAL expert on SiW ECAL simulation
à integration in FCCSW
More plans
•
Building topo-clusters to build jets
•
Using topo-clusters as PFA input
à contact with ATLAS expert established
THANK YOU!
08.02.2017
Coralie Neubüser
15