Staus at the LHC - KEKresearch.kek.jp/group/riron/workshop/KEKPH2007/March2/KEKPH07_Hama.pdf ·...
Transcript of Staus at the LHC - KEKresearch.kek.jp/group/riron/workshop/KEKPH2007/March2/KEKPH07_Hama.pdf ·...
Staus at the LHC
based on the works KH, M.M.Nojiri, A.de Roeck (hep-ph/0612060); KH, M.M.Nojiri, Y.Kuno, T.Nakaya (’04);W.Buchmüller, KH, M.Ratz, T.Yanagida (’04);
at KEKPH’07, Mar.’07
Koichi Hamaguchi (Tokyo U.)
Staus at the LHC
based on the works KH, M.M.Nojiri, A.de Roeck (hep-ph/0612060); KH, M.M.Nojiri, Y.Kuno, T.Nakaya (’04);W.Buchmüller, KH, M.Ratz, T.Yanagida (’04);
at KEKPH’07, Mar.’07
Koichi Hamaguchi (Tokyo U.)
Long-lived
Staus at the LHC
based on the works KH, M.M.Nojiri, A.de Roeck (hep-ph/0612060); KH, M.M.Nojiri, Y.Kuno, T.Nakaya (’04);W.Buchmüller, KH, M.Ratz, T.Yanagida (’04);
at KEKPH’07, Mar.’07
Koichi Hamaguchi (Tokyo U.)
Long-lived
this week
and in the early universe
+ KH, T.Hatsuda, M.kamimura, Y.Kino, T.T.Yanagida (hep-ph/0702274)W.Buchmüller, KH, M.Ibe, T.T.Yanagida (’06).
OutlineMotivation + Introduction
Long-lived staus @ LHC
Stopper-detector
Study of stau decay
Remark (catalyzed BBN)
Summary
Motivation:
Can we test the Supergravity at the LHC ?
What would prove the Supergravity ?
What would prove the Supergravity ?
Gravitino Gravitino Interaction: extremely weak
suppressed by (or )
Gravitino Mass: model dependent
!1F
!1
MPm eG!
1MP
eV keV MeV GeV TeV
GMSBgMSB̃
AMSB, mMSB
gravity-MSB
LSP: Cold Dark Matter
We assume SUSY scenarios with
Gravitino LSP (Dark Matter)
Dark Matter in SUSYIn SUSY models + conserved R-parity, the Lightest SUSY Particle (= LSP) is stable.
➞ If neutral, Dark Matter candidate.
Dark Matter candidates in SUSY Standard Model
In SUSY Standard Model in supergravity framework,...
squarks :!
"uL
"dL
#
i
"uRi"dRi
sleptons :!
"!L
"eL
#
i"eRi
gauginos and higgssinos : ""0i , $"±
i , %ggravitino : %G
Dark Matter candidates in SUSY Standard Model
In SUSY Standard Model in supergravity framework,...
neutral and color-singlet
squarks :!
"uL
"dL
#
i
"uRi"dRi
sleptons :!
"!L
"eL
#
i"eRi
gauginos and higgssinos : ""0i , $"±
i , %ggravitino : %G
Dark Matter candidates in SUSY Standard Model
In SUSY Standard Model in supergravity framework,...
neutral and color-singlet
excluded by direct detection experiments(cf. Falk, Olive, Srednicki,’94)
squarks :!
"uL
"dL
#
i
"uRi"dRi
sleptons :!
"!L
"eL
#
i"eRi
gauginos and higgssinos : ""0i , $"±
i , %ggravitino : %G
Dark Matter candidates in SUSY Standard Model
In SUSY Standard Model in supergravity framework,...
neutral and color-singlet
excluded by direct detection experiments(cf. Falk, Olive, Srednicki,’94)
Only Neutralino and Gravitino are viable candidates for the LSP dark matter!
squarks :!
"uL
"dL
#
i
"uRi"dRi
sleptons :!
"!L
"eL
#
i"eRi
gauginos and higgssinos : ""0i , $"±
i , %ggravitino : %G
Dark Matter candidates in SUSY Standard Model
In SUSY Standard Model in supergravity framework,...
neutral and color-singlet
excluded by direct detection experiments(cf. Falk, Olive, Srednicki,’94)
Only Neutralino and Gravitino are viable candidates for the LSP dark matter!
squarks :!
"uL
"dL
#
i
"uRi"dRi
sleptons :!
"!L
"eL
#
i"eRi
gauginos and higgssinos : ""0i , $"±
i , %ggravitino : %G
this talk
NLSP (Next-to-Lightest SUSY Particle)In Gravitino LSP scenario, the NLSP is long-lived.
!1F
!1
MPm eG
Interaction
Lifetime e.g. for mNLSP ! 200 GeV!NLSP ! O(day) for m eG ! 10 GeV
!NLSP ! O(10 min) for m eG ! 1 GeV!NLSP ! O(10 sec) for m eG ! 0.1 GeV
We assume SUSY scenarios with
Gravitino LSP (Dark Matter)
+ Stau NLSP.
Then, we may have a chance to test the supergravity at future colliders.....!
W.Buchmüller, K.Hamaguchi, M.Ratz, T.Yanagida ’04
Planck scale measurementW.Buchmüller, K.Hamaguchi, M.Ratz, T.Yanagida ’04
Planck scale measurementW.Buchmüller, K.Hamaguchi, M.Ratz, T.Yanagida ’04
Planck scale measurementW.Buchmüller, K.Hamaguchi, M.Ratz, T.Yanagida ’04
Is this “Planck scale measurement” possible
at the LHC ???
eV keV MeV GeV
e.g., for m!̃ = 100 GeV ,
mG̃
!!̃µs secmsnsps
kmmmmc!!̃
day
!(!̃ ! G̃! ) "m5
!̃
48"m2G̃
M2pl
!1 #
m2G̃
m2!̃
"4
Long-lived staus @ LHC
Lifetime (decay length) of NLSP stau
eV keV MeV GeV
e.g., for m!̃ = 100 GeV ,
mG̃
!!̃µs secmsnsps
kmmmmc!!̃
Detector Size
day
!(!̃ ! G̃! ) "m5
!̃
48"m2G̃
M2pl
!1 #
m2G̃
m2!̃
"4
Long-lived staus @ LHC
Lifetime (decay length) of NLSP stau
eV keV MeV GeV
e.g., for m!̃ = 100 GeV ,
mG̃
!!̃µs secmsnsps
kmmmmc!!̃
Detector Size No In-flight decay
day
!(!̃ ! G̃! ) "m5
!̃
48"m2G̃
M2pl
!1 #
m2G̃
m2!̃
"4
Long-lived staus @ LHC
Lifetime (decay length) of NLSP stau
We will see long-lived charged particle (like muon).!̃!̃
We can precisely measure its mass (by time of flight), and furthermore reconstruct masses of heavier SUSY particles.
Fig. from CMS webpage Fig. from ATLAS webpage
Here, we would like to discuss the next step.
Long-lived staus @ LHC
➔ We need to stop the staus.
Long-lived staus @ LHC
We would like to study the decay of stau (into gravitino).
➔ We need to stop the staus.
Long-lived staus @ LHC
We would like to study the decay of stau (into gravitino).
➔ We need to stop the staus.
Long-lived staus @ LHC
We would like to study the decay of stau (into gravitino).
Long-lived staus @ LHCHow thick the stopping material should be?
Fig. from Hamaguchi, Kuno, Nakaya, Nojiri ’04
!g, !q ! !!±, !!0 ! !"typically
Review of Particle Physics !"
(num
ber o
f eve
nts)
/bin
/5fb
-1
0 2 4 6 8 0
500
1000
1500
2000
Long-lived staus @ LHCHow thick the stopping material should be?
Fig. from Hamaguchi, Kuno, Nakaya, Nojiri ’04
!g, !q ! !!±, !!0 ! !"typically
Review of Particle Physics
5m Fe
for 100 GeV stau
!"
(num
ber o
f eve
nts)
/bin
/5fb
-1
0 2 4 6 8 0
500
1000
1500
2000
Long-lived staus @ LHCHow thick the stopping material should be?
Fig. from Hamaguchi, Kuno, Nakaya, Nojiri ’04
!g, !q ! !!±, !!0 ! !"typically
Review of Particle Physics
5m Fe
for 100 GeV stau
!"
(num
ber o
f eve
nts)
/bin
/5fb
-1
0 2 4 6 8 0
500
1000
1500
2000
Long-lived staus @ LHCHow thick the stopping material should be?
Fig. from Hamaguchi, Kuno, Nakaya, Nojiri ’04
!g, !q ! !!±, !!0 ! !"typically
Review of Particle Physics
5m Fe
for 100 GeV stau
!"
(num
ber o
f eve
nts)
/bin
/5fb
-1
0 2 4 6 8 0
500
1000
1500
2000
If thick enough, part of produced staus may be stopped.
Fig. from CMS webpage
Long-lived staus @ LHCActually, the LHC detector themselves can stop part of staus...
Fig. from CMS webpage
Long-lived staus @ LHCActually, the LHC detector themselves can stop part of staus...
Fig. from CMS webpage
Long-lived staus @ LHC
We may identify the position of the stopped stau, but....
Actually, the LHC detector themselves can stop part of staus...
it is difficult to identify its decay, which is out-of-time and not originating from beam interaction point.
Long-lived staus @ LHCActually, the LHC detector themselves can stop part of staus...
..... needs New Idea.
it is difficult to identify its decay, which is out-of-time and not originating from beam interaction point.
?
Long-lived staus @ LHCActually, the LHC detector themselves can stop part of staus...
..... needs New Idea.
it is difficult to identify its decay, which is out-of-time and not originating from beam interaction point.
?
Long-lived staus @ LHCActually, the LHC detector themselves can stop part of staus...
We may identify the position of the stopped stau, but....
..... needs New Idea.
Place an additional stopper-detector next to the main detector. [ Hamaguchi, Kuno, Nakaya, Nojiri, ’04 ]
Place a water tank as stopper, and then drain the water to a reservoir. [ Feng, Smith, ’04 ]
Use the stau stopped in the surrounding rock. [ De Roeck, Ellis, Gianotti, Moortgat, Olive, Pape’05 ]
Long-lived staus @ LHC
Ideas:
Place an additional stopper-detector next to the main detector. [ Hamaguchi, Kuno, Nakaya, Nojiri, ’04 ]
Place a water tank as stopper, and then drain the water to a reservoir. [ Feng, Smith, ’04 ]
Use the stau stopped in the surrounding rock. [ De Roeck, Ellis, Gianotti, Moortgat, Olive, Pape’05 ]
Long-lived staus @ LHC
Ideas:
Only this type can identify the timing and position of
the stopping stau precisely.
stopper = detector??
!!!!
!!
!!
!!
!!
High segmentation is crucial to reduce the background...
High segmentation Low segmentation
stopper = detector??
!!!!
!!
!!
!!
!!
cf. atm. neutrino CC event < 1 event/kton/year ➔ OK. charged particle at the surface of detector < 1/cm2/sec (?)
==> For SOUDAN II type detector, this corresponds to < 10% dead time of drift tube ➔ OK.
High segmentation is crucial to reduce the background...
ATLAS vs CMS
diameter length weight
ATLAS 22m 44m 7kt
CMS 15m 21m 12.5kt
CMS is smaller ➔ maybe possible to place stopper-detector(s)
-12-10-8-6 -4-2 0 2 46
810
12-10-8-6-4-20246810
-8-6-4-202468
-12-10-8-6 -4-2 0 2 46
810
3.5m
15m
15m
CMS
stopper-detector
5g/cm3
(total weight 8kt)
stopper-detectorWe assume two stoppers next to CMS.
Hamaguchi, Nojiri, De Roeck’06
CMS main cavern
Fig. from a document at a webpage of TS/CV/DC section of CERN.
テキスト
26m diameter x 60m long
stopper-detectorWe assume two stoppers next to CMS.
Hamaguchi, Nojiri, De Roeck’06
3.5m15m
CMSstopper-detector
➔ maybe possible to install stopper-detectors.
stopper-detectorWe assume two stoppers next to CMS.
Hamaguchi, Nojiri, De Roeck’06
-6
-4
-2
0
2
4
6
-6 -4 -2 0 2 4 6
y-po
sitio
n[m
]
z-positon[m]
-6
-4
-2
0
2
4
6
10 12x[m]
10.012.0
-6 -4 -2 0 2 4 6
x[m
]
distribution of stopped stau
-12-10-8-6 -4-2 0 2 46
810
12-10-8-6-4-20246810
-8-6-4-202468
-12-10-8-6 -4-2 0 2 46
810
GM point! = 40 TeV Hamaguchi, Nojiri, De Roeck, ’06
How many staus are stopped?
table, too
Hamaguchi, Nojiri, De Roeck, ’06
up to O(1000) staus are trapped!
lifetime measurement ➔ SUSY breaking scale
0
2
4
6
8
10
12
14
16
18
0 1 2 3 4 5 6 7 8 9
tdecay ! tstop [in unit of lifetime]
num
ber
ofev
ents
/bi
n
0
2
4
6
8
10
0.7 0.8 0.9 1 1.1 1.2 1.3 1.4 1.5
lifetime [arbitrary unit]2!
lnL
for N = 100
Hamaguchi, Nojiri, de Roeck ’06
lifetime !!1 ! F 2 ,"
F =!
m eGMP = SUSY breaking scale
Note: possible only in a real-time detector
!!/! = 10 ! 15% for Ne! = 100!!/! = 3 ! 4% for Ne! = 1000
Motivation:
Can we test the Supergravity at the LHC ?
Planck scale measurementW.Buchmüller, K.Hamaguchi, M.Ratz, T.Yanagida ’04
Planck scale measurementCrucial to determine the tau energy precisely.
0
50
100
150
200
250
0 20 40 60 80 100 120 140 160
E! [GeV]
mX
[GeV
]
10yrs 1 yr
monthday
m!̃ = 100 GeV
m!̃ = 150 GeV
m!̃ = 200 GeV
m!̃ = 250 GeV
m!̃ = 300 GeV
m eG =!
m2e! ! 2me! E! + m2
!
Figs. from Hamaguchi, Nojiri, De Roeck, ’06(cf. for ILC, see Martyn’06.)
Planck scale measurementCrucial to determine the tau energy precisely.
0
50
100
150
200
250
0 20 40 60 80 100 120 140 160
E! [GeV]
mX
[GeV
]
10yrs 1 yr
monthday
m!̃ = 100 GeV
m!̃ = 150 GeV
m!̃ = 200 GeV
m!̃ = 250 GeV
m!̃ = 300 GeV
m eG =!
m2e! ! 2me! E! + m2
!
0
20
40
60
80
100
120
140
160
0 20 40 60 80 100 120
(a)
Low Stat.Best Fit
Ejet [GeV]
num
ber
ofev
ents
/bi
n
0
2
4
6
8
10
50 55 60 65 70 75 80 85 90 95 100
(b)
E! [GeV]
2!ln
L
-1
-0.5
0
0.5
1
50 55 60 65 70 75 80 85 90 95 100
(c)
E! [GeV]
P!
Figs. from Hamaguchi, Nojiri, De Roeck, ’06(cf. for ILC, see Martyn’06.)
!Ejet/Ejet = 150%/!
Ejet/GeV
Planck scale measurementCrucial to determine the tau energy precisely.
0
50
100
150
200
250
0 20 40 60 80 100 120 140 160
E! [GeV]
mX
[GeV
]
10yrs 1 yr
monthday
m!̃ = 100 GeV
m!̃ = 150 GeV
m!̃ = 200 GeV
m!̃ = 250 GeV
m!̃ = 300 GeV
m eG =!
m2e! ! 2me! E! + m2
!
0
20
40
60
80
100
120
140
160
0 20 40 60 80 100 120
(a)
Low Stat.Best Fit
Ejet [GeV]
num
ber
ofev
ents
/bi
n
0
2
4
6
8
10
50 55 60 65 70 75 80 85 90 95 100
(b)
E! [GeV]
2!ln
L
-1
-0.5
0
0.5
1
50 55 60 65 70 75 80 85 90 95 100
(c)
E! [GeV]
P!
Figs. from Hamaguchi, Nojiri, De Roeck, ’06(cf. for ILC, see Martyn’06.)
!Ejet/Ejet = 150%/!
Ejet/GeV
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8mX/m!̃
!mX
/m!̃
m!̃ = 150 GeV, N! = 100010 yrsyrmonth
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8mX/m!̃
!mX
/m!̃
m!̃ = 150 GeV, N! = 10010 yrsyrmonth
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8mX/m!̃
!mX
/m!̃
m!̃ = 200 GeV, N! = 100010 yrsyrmonth
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8mX/m!̃
!mX
/m!̃
m!̃ = 200 GeV, N! = 10010 yrsyrmonth
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8mX/m!̃
!mX
/m!̃
m!̃ = 300 GeV, N! = 100010 yrsyrmonth
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8mX/m!̃
!mX
/m!̃
m!̃ = 300 GeV, N! = 10010 yrsyrmonth
00 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
mG̃/m!̃
! MP
[GeV
]
m!̃ = 150 GeV, N! = 100010 yrsyrmonth
1 · 1018
2 · 1018
3 · 1018
4 · 1018
5 · 1018
6 · 1018
00 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
mG̃/m!̃
! MP
[GeV
]
m!̃ = 150 GeV, N! = 10010 yrsyrmonth
1 · 1018
2 · 1018
3 · 1018
4 · 1018
5 · 1018
6 · 1018
00 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
mG̃/m!̃
! MP
[GeV
]
m!̃ = 200 GeV, N! = 100010 yrsyrmonth
1 · 1018
2 · 1018
3 · 1018
4 · 1018
5 · 1018
6 · 1018
00 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
mG̃/m!̃
! MP
[GeV
]
m!̃ = 200 GeV, N! = 10010 yrsyrmonth
1 · 1018
2 · 1018
3 · 1018
4 · 1018
5 · 1018
6 · 1018
00 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
mG̃/m!̃
! MP
[GeV
]
m!̃ = 300 GeV, N! = 100010 yrsyrmonth
1 · 1018
2 · 1018
3 · 1018
4 · 1018
5 · 1018
6 · 1018
00 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
mG̃/m!̃
! MP
[GeV
]
m!̃ = 300 GeV, N! = 10010 yrsyrmonth
1 · 1018
2 · 1018
3 · 1018
4 · 1018
5 · 1018
6 · 1018
Possible if
mass reconstruction Mp measurement
Hamaguchi, Nojiri, de Roeck, ’06
1σ
m eG > (0.2 ! 0.3)me!
• may be inconsistent with BBN bounds (especially catalyzed BBN).
Remarkm eG > (0.2 ! 0.3)me!
Recently, bound-state effects have been discussed. ( negatively charged stau ↔ positively charged nuclei )
Pospelov ’06; Kohri, Takayama ’06; Kaplinghat, Rajaraman ’06; Cyburt, Ellis, Fields, Olive, Spanos ’06,KH, Hatsuda, Kamimura, Kino, Yanagida ’07
Pospelov ’06
?!!
• may be inconsistent with BBN bounds (especially catalyzed BBN).
Remarkm eG > (0.2 ! 0.3)me!
catalyzed BBNstandard BBN
enhanced
KH, Hatsuda, Kamimura, Kino, Yanagida ’07
• may be inconsistent with BBN bounds (especially catalyzed BBN).
Remarkm eG > (0.2 ! 0.3)me!
Solved the Schroedinger eq. for 3-body system (He4, d, X) exactly,using the state-of-the-art coupled-channel technique.
Boundstate
Li6
D + (4HeX) ! 6Li + X
KH, Hatsuda, Kamimura, Kino, Yanagida ’07
• may be inconsistent with BBN bounds (especially catalyzed BBN).
Remarkm eG > (0.2 ! 0.3)me!
Solved the Schroedinger eq. for 3-body system (He4, d, X) exactly,using the state-of-the-art coupled-channel technique.
Boundstate
Li6
D + (4HeX) ! 6Li + Xastrophysical S-factor
KH, Hatsuda, Kamimura, Kino, Yanagida ’07
• may be inconsistent with BBN bounds (especially catalyzed BBN).
Remarkm eG > (0.2 ! 0.3)me!
Solved the Schroedinger eq. for 3-body system (He4, d, X) exactly,using the state-of-the-art coupled-channel technique.
Boundstate
Li6
D + (4HeX) ! 6Li + Xastrophysical S-factor
3 4 5 6 7 8Log10!tau_X"sec#$
-16
-15
-14
-13
-12
log10!nX%
s$
-16
-15
-14
-13
-12
X Lifetime
X abundance
upper bound
thermal relic
• But if there is an entropy production of O(a few 100) after NLSP decoupling, the bounds can be avoided.
• may be inconsistent with BBN bounds (especially catalyzed BBN).
Remarkm eG > (0.2 ! 0.3)me!
3 4 5 6 7 8Log10!tau_X"sec#$
-16
-15
-14
-13
-12
log10!nX%
s$
-16
-15
-14
-13
-12
Lifetime
abundance
upper bound
thermal relic O(300)
KH, Hatsuda, Kamimura, Kino, Yanagida ’07
SummaryFor the gravitino LSP, the NLSP becomes long-lived.
To study the decay of a long-lived charged NLSP, a stopper-detector seems necessary.
O(1)kton stopper-detector may be placed next to the CMS detector.
Stau lifetime is measured well.
If , the mass reconstruction (and hence Mp measurement !) may be possible.
Catalyzed BBN is a problem, but may be solved.
m eG > (0.2 ! 0.3)me!
SummaryFor the gravitino LSP, the NLSP becomes long-lived.
To study the decay of a long-lived charged NLSP, a stopper-detector seems necessary.
O(1)kton stopper-detector may be placed next to the CMS detector.
Stau lifetime is measured well.
If , the mass reconstruction (and hence Mp measurement !) may be possible.
Catalyzed BBN is a problem, but may be solved.
m eG > (0.2 ! 0.3)me!
Anyway, if long-lived charged particles are seen at the LHC,............. trap them!!
NLSP
• Which particle is the NLSP?
• Usually , and therefore, the NLSP is neutralino or slepton.
• Among sleptons, typically a charged slepton, especially the stau is the lightest. (but sneutrino NLSP is also possible.)
• In general, other SUSY particle can also be NLSP.
me! ! meq me!01
< me!±1
< meg
!!
NLSP
• Which particle is the NLSP?
• Usually , and therefore, the NLSP is neutralino or slepton.
• Among sleptons, typically a charged slepton, especially the stau is the lightest. (but sneutrino NLSP is also possible.)
• In general, other SUSY particle can also be NLSP.
me! ! meq me!01
< me!±1
< meg
!!
stopper = detector??Hamaguchi, Kuno, Nakaya, Nojiri, ’04
study of 3 body decay
• LSP may be another weakly interacting particle, like axino
• We want to distinguish the decay into the gravitino from the decay into axino by studying the 3-body decay:
3-body decay ... gravitino vs axino
!! ! X!", (X = !G or !a)
!a.
cf.Brandenburg, Covi, Hamaguchi, Roszkowski, Steffen, ’05Buchmüller, Hamaguchi, Ratz, Yanagida ’04
X
! !
3-body decay ... gravitino vs axino
!
E! X = !G or !a ??
!E!/E! = 100%/!
E!/GeV
Required number of staus to see 3sigma diff.
!E! = me" /8 (cut : E! > 10 GeV)!! = "/3 (cut : ! > "/6)
3-body decay ... gravitino vs axinoWe divide and into bins,E! !
mea, m eG ! me! , ! = numerical parameter (not yet calculated)
Buchmüller, Hamaguchi, Ibe, Yanagida ’06