2014.07.16 Seminar at Kyoto U.

1. Yoshitaro
Takaesu
U.
of
Tokyo
LHC
limits
on
the
Higgs-­‐portal
models
arXiv:
1407.XXXX
in
collabora2on
with
M.
Endo
(U.Tokyo)

2. Portal
models
to
Hidden
Sector
2
Consider
another
world
where
par2cles
are
SM
singlets
(Hidden
Sector).
The
par2cles
interacts
to
our
SM
world
through
Gravity.
Also,
they
may
interact
through…
DM
?
HL
FY
µ Xµ
1
fS
Fµ
˜Fµ
S
|H|2
S2
Neutrino
Portal
Vector
Portal
Axion
Portal
Higgs
Portal
Sterile
neutrino
Dark
Photon
Axino-­‐like
par2cle
Higgs
invisible
decay
SM
Hidden
G
In
this
talk,
we
discuss
the
Higgs-­‐portal
possibility.

3. Constraints
on
Higgs-­‐portal
DM
models
3
• Relic
abundance
• Direct
detec2on
• Collider
search
Tight
constraints
on
Higgs-­‐portal
DM.
S2ll
important
to
know
to
what
extent
“LHC”
can
explore
the
heavier
Higgs-­‐portal
models.
Heavy
Higgs-­‐portal
DM
search
[Simone,
Giudice,
Strumia:
1402.6287]
WIMP

4. Collider
search
of
Heavy
Higgs-­‐potal
WIMP
4

5. Direct
searches
for
Higgs
invisible
decay
at
the
LHC
5
Vector
Boson
Fusion
(VBF)
BR_inv
<
0.65
[CMS:
8TeV
19.5
a^-­‐1:
1404.1344]
Z
associated
producNon
(ZH)
BR_inv
<
0.75
[ATLAS:
8TeV
20.3
a^-­‐1:
1402.3244]
BR_inv
<
0.81
[CMS:
8TeV
19.5
a^-­‐1:
1404.1344]
• Good
S/B
(Z-­‐mass
constraint,
2-­‐lepton
+missing)
• Cross
sec2on
is
small
• Useful
for
high
luminosity
• 2nd
largest
Higgs
produc2on
process
• Good
S/B
(large
rapidity
gap
of
2
energe2c
forwarding
jets)
SM
predic2on:
BR(H ZZ 2 2 ) 0.1%
Sizable
BR_inv
is
an
evidence
of
BSM
models!

6. Higgs
producNon
Cross
SecNons
Gluon-­‐fusion
VBF
WH
ZH

7. Mono-­‐X
searches
7
Mono-­‐X
searches
(X
+missing
pT)
are
also
sensi2ve
to
Higgs-­‐portal
models.
Mono-­‐jet
• Large
Cross
sec2on
• Main
mono-­‐X
mode
so
far
• S/B
is
not
good
• Gluon-­‐fusion
Higgs
produc2on
Mono-­‐Z
• S/B
is
good
(Z-­‐mass
constraint)
• Cross
sec2on
is
small
• Useful
for
high
luminosity
• ZH
produc2on
Mono-­‐lepton
• S/B
is
good
(but
no
W-­‐mass
constraint)
• Cross
sec2on
is
small
(but
larger
than
mono-­‐Z)
• Useful
for
high
luminosity
• WH
produc2on

8. We
will
inves2gate
the
constraints
of
the
LHC
invisible
searches
on
Heavier
Higgs-­‐portal
WIMP
models.

9. Higgs-­‐portal
models
to
be
studied
9
Scalar
Vector
AnN-­‐sym.
Tensor
(transverse)
S, Vµ, Bµ are
SM
singlets.
parity
is
assumed
for
and
to
ensure
their
stability.
m2
B = M2
B + 4cBv2
m2
V = M2
V + 2cV v2
m2
S = M2
S + 2cSv2
LV =
1
4
V µ
Vµ +
1
2
M2
V V µ
Vµ + cV |H|2
V µ
Vµ V (V µ
Vµ)2
LB =
1
4
Bµ
Bµ
1
2
µ
Bµ B
1
4
M2
BBµ
Bµ cB|H|2
Bµ
Bµ
BBµ B B B µ
LS =
1
2
µ
S µS
1
2
M2
SS2
cS|H|2
S2
SS4
Z2 S Vµ
ajer
EWSB
Fermionic
hidden
par2cle
is
not
considered
for
simplicity.
(SM
singlet
has
only
the
Higgs-­‐portal
interac2on.
)
Bµ
[A.
Djouadi
et
al.1205.3169,
S.Kanemura
et
al.1005.5651
]
[O.Cata,
A.
Ibarra:
1404.0432]

10. Cross
secNon
of
WIMP-­‐pair
producNon
10
We
can
express
the
WIMP
produc2on
cross
sec2on
as
This
is
the
basic
formulae
for
our
analysis.

11. Analysis
Details
11
• VBF
Higgs
invisible
decay
• Mono-­‐jet
• Mono-­‐Z
*
ZH,
mono-­‐lepton
results
(profile-­‐based)
will
not
be
used
since
they
rely
on
the
on-­‐shell
Higgs
produc2on
topology.

12. VBF
analysis
(CMS
,
1404.1344)
12
We
calculate
under
the
following
cuts
(w/
MCFM-­‐6.8):
Compare
to
the
upper
bound
on
the
signal
events.
Nlim
s = 210 0.65 137
95%
CL
upper
bound
H(pp jj H; mH)
19.5 fb 1
pp H jj jj
c2
(m ) <
Nlim
s
(m , c = 1)L
(m , c )L < Nlim
s
First
VBF
for
BR_inv

13. Mono-­‐jet
analysis
13
pp H j j
We
would
like
to
evaluate
the
cross
sec2on
at
least
NLO
QCD
order.
However,
NLO
cross
sec2ons
are
only
known
in
limit.
mt
We
approximate
the
NLO
cross
sec2on
as
LO
K-­‐factor
K-­‐factor
[R.V.Handler
et
al.
1206.0157]
[L.Altenkamp
et
al.
1211.5015]

14. Mono-­‐jet
analysis
(CMS-­‐PAS-­‐EXO-­‐12-­‐048
)
14
pp H j j
We
calculate
under
the
following
cuts
(w/
MCFM-­‐6.8):
NLO
H (pp jH; mH)
pT H > 450 GeV (for LO
(mt))
pT H > mH/2 (for K factor)
pT j1 > 110 GeV, | j1 | < 2.4
• Taming
the
infinite
top
mass
effects
• Avoiding
large
region
log(mH/pT H)
giving
the
most
stringent
limit
19.5 fb 1
(*
2nd
jet
with
pT
>
30
GeV
(from
NLO
real
emission)
is
not
vetoed,
due
to
technical
reason.
)

15. Mono-­‐Z
analysis
(ATLAS
,
1404.0051)
15
We
calculate
under
the
following
cuts
(w/
HAWK-­‐2.0):
H(pp ZH; mH)
20.3 fb 1
pµ
T > 20 GeV, | µ
| < 2.5
pe
T > 20 GeV, | e
| < 2.47
76 GeV < mll < 106 GeV
| ll
| < 2.5
pT > 150 GeV giving
the
most
stringent
limit

16. 8
TeV
LHC
constraints
16

17. Limits
for
the
Heavy
Higgs-­‐portal
WIMPs
17
S =
c2
Sv2
8 mH
1
4m2
S
m2
H
B =
c2
Bv2
4 mH
m4
H 4m2
Hm2
B + 6m4
B
m4
B
1
4m2
B
m2
H
V =
c2
V v2
32 mH
m4
H 4m2
Hm2
V + 12m4
V
m4
V
1
4m2
V
m2
H
0.1
0.2
0.5
1
2
5
10
50 100 150 200 250 300
cχ
mχ
[GeV]
VBF
Mono-jet
Mono-Z
0.1
0.2
0.5
1
2
5
10
50 100 150 200 250 300
cχ
mχ
[GeV]
0.1
0.2
0.5
1
2
5
10
50 100 150 200 250 300
cχ
mχ
[GeV]
0.1
0.2
0.5
1
2
5
10
50 100 150 200 250 300
cχ
mχ
[GeV]
0.1
0.2
0.5
1
2
5
10
50 100 150 200 250 300
cχ
mχ
[GeV]
0.1
0.2
0.5
1
2
5
10
50 100 150 200 250 300
cχ
mχ [GeV]
VBF
Mono-jet
Mono-Z
0.1
0.2
0.5
1
2
5
10
50 100 150 200 250 300
cχ
mχ [GeV]
0.1
0.2
0.5
1
2
5
10
50 100 150 200 250 300
cχ
mχ [GeV]
0.1
0.2
0.5
1
2
5
10
50 100 150 200 250 300
cχ
mχ [GeV]
0.1
0.2
0.5
1
2
5
10
50 100 150 200 250 300
cχ
mχ [GeV]
0.1
0.2
0.5
1
2
5
10
50 100 150 200 250 300
cχ
mχ
[GeV]
VBF
Mono-jet
Mono-Z
0.1
0.2
0.5
1
2
5
10
50 100 150 200 250 300
cχ
mχ
[GeV]
0.1
0.2
0.5
1
2
5
10
50 100 150 200 250 300
cχ
mχ
[GeV]
0.1
0.2
0.5
1
2
5
10
50 100 150 200 250 300
cχ
mχ
[GeV]
0.1
0.2
0.5
1
2
5
10
50 100 150 200 250 300
cχ
mχ
[GeV]
Tensor
Vector
Scalar
Data
:
BG
VBF
390
:
332(58)
Mono-­‐jet
1772
:
1931(131)
Mono-­‐Z
45
:
52(18)

18. 14
TeV
LHC
prospects
18

19. How
to
perform
(theorist’s)
projecNon
19
We
need
to
know
and
to
es2mate
the
14
TeV
constraints
on
.
Nlim
sig
cc2
(m ) <
Nlim
sig
(m , c = 1)L
is
roughly
es2mated
with
the
following
assump2ons:
Nlim
sig
95%
CL
(simple
Gaussian)
sys
BG does
not
improve
stat
BG reduces
as
Nlim
sig 2 BG
1/ NBG
NBG increases
due
to
PDF
(luminosity
ra2o)
and
integrated
luminosity
L
is
es2mated
by
theore2cal
calcula2ons
with
experimental
cuts.
8TeV
data

20. Mono-­‐jet
channel:
14
TeV
LHC
20
1
10
100
1000
65 80 100 120 140 160 180 200 220 240
CrossSection/c2
χ[fb]
mχ
[GeV]
Tensor DM
pTcut = 400 GeV
600 GeV
800 GeV
1
10
100
1000
65 80 100 120 140 160 180 200 220 240
CrossSection/c2
χ[fb]
mχ
[GeV]
Tensor DM Vector DM
pTcut = 400 GeV
600 GeV
800 GeV
1
10
100
1000
65 80 100 120 140 160 180 200 220 240
CrossSection/c2
χ[fb]
mχ
[GeV]
Tensor DM Vector DM
Scalar DM
pTcut = 400 GeV
pp H j j Cross
Sec2ons
at
14
TeV
Cx
<
1
(100
1/a)
Cx
<
0.2
(100
1/a)
Nlim
s (pT > 400) 2000 (L = 100 fb 1
)

21. Mono-­‐jet
SensiNvity
21
0
1
2
3
4
5
6
7
8
Tensor
Vector
Scalar
Mono-­‐J
8TeV
14TeV
400
(100)
400
(3,000)
600
(100)
600
(3,000)
VBF
8TeV
14TeV
(100)
ZH
8TeV
14TeV
(300)
14TeV
(3,000)
clim
m = 70GeV
pcut
T (L)
*
Rough
Es2mate
Tensor

22. Mono-­‐Z
channel:
14
TeV
LHC
22
0.01
0.1
1
10
100
65 80 100 120 140 160 180 200 220 240
CrossSection/c2
χ[fb]
mχ
[GeV]
Tensor DM
pTcut = 150 GeV
250 GeV
350 GeV
450 GeV
0.01
0.1
1
10
100
65 80 100 120 140 160 180 200 220 240
CrossSection/c2
χ[fb]
mχ
[GeV]
Tensor DM Vector DM
pTcut = 150 GeV
250 GeV
350 GeV
450 GeV
0.01
0.1
1
10
100
65 80 100 120 140 160 180 200 220 240
CrossSection/c2
χ[fb]
mχ
[GeV]
Tensor DM Vector DM
Scalar DM
pTcut = 150 GeV
250 GeV
350 GeV
450 GeV
Cross
Sec2ons
at
14
TeV
(L = 100 fb 1
)Nlim
s (pT > 450) 5
pp ZH Z

23. VBF
and
ZH
channels
23
[5]
ATLAS,
1402.3244
[6]
CMS,
1404.1344
[16]
D.Gosh
et
al.,
1211.7015
[17]
ATL-­‐PHYS-­‐PUB-­‐2013-­‐014
[18]
Snowmass,
1309.7925
95%
Upper
bounds
on
the
Higgs
inv.
decay
ra2o
at
mH
=
125
GeV
The
VBF
bound
will
be
improved
by
a
factor
of
4
at
mH
=
125
GeV.
The
Upper
bound
on
improves
a
factor
of
2.
c
=
4m2
d˜s
2
H(˜s) (˜s)
2 ˜s
(˜s m2
H)2 + 2
Hm2
H
The
ZH
bound
will
be
improved
by
a
factor
of
2
~
4
(300
1/a)
and
4
~
12
(3,000
1/a).
The
Upper
bound
on
will
be
improved
by
a
factor
of
1.5
~
2
(300
1/a)
and
2
~
3.5
(3,000
1/a).
c
If
this
level
of
improvement
holds
for
any
mH,
the
Upper
bound
on
improves
a
factor
of
4.
Profile-­‐based
Cut-­‐based

24. SensiNvity
Summary
(Mono-­‐j,
VBF,
Mono-­‐Z)
24
0
2
4
6
8
10
12
Tensor
Vector
Scalar
Mono-­‐J
8TeV
14TeV
400
(100)
400
(300)
600
(100)
600
(300)
Mono-­‐Z
8TeV
14TeV
450
(100)
450
(300)
VBF
8TeV
14TeV
(100)
m = 70GeV
MJ
MZ
VBF
MJ
MZ
VBF
MJ
MZ
VBF
*
Rough
Es2mate
Tensor
MJ
MZ
VBF
clim

25. Summary
25
LHC
constraints
on
the
Heavy
Higgs-­‐portal
models
have
been
Studied.
8
TeV
LHC
results
can
access
the
Higgs-­‐portal
couplings
below
1
for
the
vector
and
tensor
case.
Scalar
coupling
limit
is
very
weak.
14
TeV
LHC
can
reach
at
O(0.1)
couplings
for
vector
and
tensor
case.
The
scalar
coupling
below
O(1)
will
be
remained
unexplored.
VBF
channel
already
shows
good
performance
in
8
TeV
LHC,
replacing
the
mono-­‐jet
channel.
ZH
channel
will
also
be
a
leading
channel
in
14
TeV
LHC.