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. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Dark matter searches at high energy colliders
Zhao-Huan YU (余钊焕)
Key Laboratory of Particle Astrophysics,Institute of High Energy Physics, CAS
December 13, 2013
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 1 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Dark matter
Dark matter (DM) in the Universe
Dark matter exists at various scales in the Universe.(galaxies, clusters, large scale structures, cosmological scale)
However, its microscopic property remains unknown.
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 2 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Dark matter
Different kinds of DM detections
DMDM
SMSM
Unknownphysics
Direct detection
Inirectdetection
Colliderdetection
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 3 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Direct detection
DM direct detection
Detect recoil signals of nuclei scattered by DM particles(photons, phonons, ionization)
Work underground to reduce cosmic ray backgrounds
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 4 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Direct detection
Direct detection results (spin independent)
]2WIMP Mass [GeV/c6 7 8 910 20 30 40 50 100 200 300 400 1000
]2W
IMP-
Nuc
leon
Cro
ss S
ectio
n [c
m
-4510
-4410
-4310
-4210
-4110
-4010
-3910
]2WIMP Mass [GeV/c6 7 8 910 20 30 40 50 100 200 300 400 1000
]2W
IMP-
Nuc
leon
Cro
ss S
ectio
n [c
m
-4510
-4410
-4310
-4210
-4110
-4010
-3910
]2WIMP Mass [GeV/c6 7 8 910 20 30 40 50 100 200 300 400 1000
]2W
IMP-
Nuc
leon
Cro
ss S
ectio
n [c
m
-4510
-4410
-4310
-4210
-4110
-4010
-3910
DAMA/I
DAMA/Na
CoGeNT
CDMS (2010/11)EDELWEISS (2011/12)
XENON10 (2011)
XENON100 (2011)
COUPP (2012)
SIMPLE (2012)
ZEPLIN-III (2012)
CRESST-II (2012)
XENON100 (2012)observed limit (90% CL)
Expected limit of this run:
expectedσ 2 ± expectedσ 1 ±
⇐ XENON100, arXiv:1207.5988
mWIMP (GeV/c2)
WIM
P−nu
cleo
n cr
oss
sect
ion
(cm
2 )
101 102 103
10−45
10−44
6 8 10 12
10−44
10−42
10−40
LUX, arXiv:1310.8214 ⇒ LUX
XENON100
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 5 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Indirect detection
DM indirect detection
Search for products from DM annihilation or decay
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 6 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Indirect detection
Indirect detection experiments
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 7 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Indirect detection
Indirect detection results
10-2
10-1
100
100
101
102
103
e+/(
e- +
e+)
E (GeV)
bkgdm
total
10-2
10-1
100
100
101
102
103
e+/(
e- +
e+)
E (GeV)
AMSHEAT94+95
HEAT00PAMELAAMS-02
AMS-02 positron fraction interpretedby the DM annihilation into τ+τ−
[Yuan, Bi, et al., arXiv:1304.1482]
e+/(
e−
+ e
+)
E (GeV)
AMSHEAT94+95HEAT00PAMELA
AMS02TotalBkgGeminga
10-2
10-1
100
100
101
102
103
AMS-02 positron fraction interpretedby the nearby pulsar Geminga[Yin, ZHY, Yuan, Bi, arXiv:1304.4128]
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 8 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Indirect detection
10−22
10−23
10−24
10−25
10−26
〈σv〉(
cm3
s−1)
e+e−
Observed Limit
Median Expected
68% Containment
95% Containment
10−22
10−23
10−24
10−25
10−26
〈σv〉(
cm3
s−1)
µ+µ−
101 102 103
Mass (GeV/c2)
10−22
10−23
10−24
10−25
10−26
〈σv〉(
cm3
s−1)
τ+τ−
uu
bb
101 102 103
Mass (GeV/c2)
W+W−
Fermi γ-ray observations on15 dwarf spheroidal satellitegalaxies of the Milky Wayhas set strict constraints onDM annihilations.
Reach down to the canonicalannihilation cross section ofthermal produced dark mat-ter (∼ 3× 10−26 cm3 s−1).
[arXiv:1310.0828]
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 9 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Colliders
Past and current hadron colliders
TEVATRON: pp collider(Fermilab, 1987-2011)Circumference: 6.28 kmCollision energy: ps = 1.96 TeVLuminosity: ∼ 4.3× 1032 cm−2 s−1
Detectors: CDF, D;
LHC: pp collider (also pPb, PbPb)(CERN, 2009-)Circumference: 26.659 kmCollision energy: ps = 7, 8, 13, 14 TeVLuminosity: ∼ 50−500×1032 cm−2 s−1
Detectors: ATLAS, CMS, ALICE, LHCb
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 10 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Colliders
Future e+e− colliders
ILC: International Linear ColliderCollision energy:p
s = 250, 350, 500, 1000 GeVLuminosity: ∼ 75−500×1032 cm−2 s−1
Detectors: SiD, ILD
CEPC: Circular Electron-Positron Collider (China)Collision energy: ps ∼ 250 GeV
CLIC: Compact Linear ColliderCollision energy: ps ∼ 1− 3 TeV
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 11 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
DM searching at colliders
Particle identification in collider detectors
How about DM particles? Missing energy (/E or /ET)(similar to neutrinos)
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 12 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
DM searching at colliders
DM searching channels at colliders.
......
g
g
bχ02
ℓ−
g qχ+
1 νℓ′
g
g
bb
qq′
ℓ+
ℓ−
χ01
χ01
νℓ′
ℓ′+
.
......
q
q
g
χ
χ
q
Social DMAccompanied by other new particles
Complicated decay chainsVarious final states(jets+ leptons+ /ET, ...)
Maverick DMDM particle is the only new particle
reachable at the collision energyMono-X+ /E final states
(monojet, mono-γ, mono-W/Z , ...)
(Classified by Rocky Kolb)Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 13 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
DM searching at colliders
Results from LHC
]2 [GeV/cχM1 10
210
310
]2
-Nucle
on C
ross S
ection [
cm
χ
-4610
-4410
-4210
-4010
-3810
-3610
-3410
-3210
-3010
-2810
-2710CMS 2012 Vector
CMS 2011 Vector
CDF 2012
XENON100 2012
COUPP 2012
SIMPLE 2012
CoGeNT 2011
CDMSII 2011
CDMSII 2010
CMS Preliminary = 8 TeVs
Spin Independent
-1L dt = 19.5 fb∫
2Λ
q)µγq)(χ
µγχ(
]2 [GeV/cχM1 10
2103
10
]2
-Nu
cle
on
Cro
ss S
ectio
n [
cm
χ
-4610
-4410
-4210
-4010
-3810
-3610
-3410
-3210
-3010
-2810
-2710CMS 2012 Axial Vector
CMS 2011 Axial Vector
CDF 2012
SIMPLE 2012
CDMSII 2011
COUPP 2012
-
W+
Super-K W-
W+IceCube W
CMS Preliminary = 8 TeVs
-1L dt = 19.5 fb∫
Spin Dependent
2Λ
q)5
γµγq)(χ5
γµ
γχ(
Constraints on DM-nucleon scattering cross section given by the CMSdark matter search in the monojet+ /ET final state with an integratedluminosity of ∼ 20 fb−1 at ps = 8 TeV
[CMS PAS EXO-12-048]Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 14 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
DM searching at colliders
Expected sensitivity at the CEPC.
......
e
e−
e+
γ
χ
χ
e
e−
e+
χ
χ
γ
Oe =1Λ2 χΓχχ eΓee
Λ
(Ge
V)
mχ (GeV)
e+e
− collider, √s = 250 GeV
100 fb-1
1000 fb-1
Γχ = 1, Γe = 1
Γχ = γ5, Γe = γ5
Γχ = γ µ, Γe = γµ
Γχ = γ µγ5, Γe = γµγ5
0
200
400
600
800
1000
1200
1400
1600
0 20 40 60 80 100 120
< σ
an
nv >
(c
m3 s
-1)
mχ (GeV)
e+e
− collider, √s = 250 GeV
100 fb-1
1000 fb-1
Γχ = γ5, Γe = γ5
Γχ = γ µ, Γe = γµ
Fermi 4-year upper limit
10-31
10-30
10-29
10-28
10-27
10-26
10-25
10-24
10-23
5 50 1 10 100
Expected sensitivities (3σ reaches) tointeractions between DM and electronsin the monophoton+ /E searchingchannel at the circular electron-positroncollider (CEPC)
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 15 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
γ-ray line spectrum
γ-ray emission from DM: line spectrum
In general, DM particles (χ) should not have electric chargeand not directly couple to photons
⇓DM particles may couple to photons via high order loop diagrams(highly suppressed, the branching fraction may be only ∼ 10−4− 10−1)
χ
χ
γ
γ
For nonrelativistic DM particles, thephotons produced in χχ → γγ would bemono-energetic
⇓A γ-ray line at energy ∼ mχ
(“smoking gun” for DM particles)
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 16 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
γ-ray line spectrum
γ-ray emission from DM: line spectrum
In general, DM particles (χ) should not have electric chargeand not directly couple to photons
⇓DM particles may couple to photons via high order loop diagrams(highly suppressed, the branching fraction may be only ∼ 10−4− 10−1)
χ
χ
γ
γ For nonrelativistic DM particles, thephotons produced in χχ → γγ would bemono-energetic
⇓A γ-ray line at energy ∼ mχ
(“smoking gun” for DM particles)
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 16 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
γ-ray line spectrum
A γ-ray line from the Galactic center region?
0
5
10
15
20
25
30
35
40
Counts
p-value=0.85, χ 2red=14.3/21
Signal counts: 53.4 (4.26σ) 80.5 - 208.5 GeV
Reg3 (ULTRACLEAN), Eγ =129.6 GeV
100 150 200
E [GeV]
-10
0
10
Counts - Model
Weniger, 1204.2797
Residual map
180 90 0 -90 -18000
-90
-45
0
45
90
00
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
-1.0
-0.5
0.0
0.5
1.0
1.5
2.0
2.5
keV cm
-2 s-1 sr -1
Su & Finkbeiner, 1206.1616
Using the 3.7-year Fermi-LAT γ-ray data, several analyses showed thatthere might be evidence of a monochromatic γ-ray line at energy∼ 130 GeV, originating from the Galactic center region (about 3− 4σ).It may be due to DM annihilation with
σannv�∼ 10−27 cm3 s−1.
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 17 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
γ-ray line spectrum
(GeV)χm10 210
)-1 s3
95%
CL
Lim
it (c
mγγ
v>σ<
-3010
-2910
-2810
-2710
-2610
-25103.7 year R41 NFW Profile
Observed Upper LimitExpected LimitExpected 68% ContainmentExpected 95% Containment
Eve
nts
/ 5.0
GeV
0
10
20
30
40
50
60
70 = 133.0 GeVγP7_REP_CLEAN R3 2D E
= 17.8 evtssign
σ = 3.3 locals
= 276.2 evtsbkgn
= 2.76bkgΓ
(c)
Energy (GeV)60 80 100 120 140 160 180 200 220
)σR
esid
. (
-4-2024
Recently, the Fermi-LAT Collaboration has released its official spectralline search in the energy range 5− 300 GeV using 3.7 years of data.They did not find any globally significant lines and set 95% CL upperlimits for DM annihilation cross sections.Their most significant fit occurred at Eγ = 133 GeV and had a localsignificance of 3.3σ, which translates to a global significance of 1.6σ.
Fermi-LAT Collaboration, 1305.5597Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 18 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Collider sensitivity
DM-photon interaction at e+e− colliders
χ
χ
γ
γ
⇒γ
e−
e+
χ
χ
γ
The coupling between DM particles and photons that induce theannihilation process χχ → γγ can also lead to the process e+e−→ χχγ.Therefore, the possible γ-ray line signal observed by Fermi-LAT may betested at future TeV-scale e+e− colliders.
DM particles escape from the detector⇓
Signature: a monophoton associating with missing energy (γ+ /E)Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 19 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Collider sensitivity
Effective operator approachIf DM particles couple to photons via exchanging some mediators whichare sufficiently heavy, the DM-photon coupling can be approximatelydescribed by effective contact operators.
For Dirac fermionic DM, consider OF =1
Λ3 χ iγ5χFµν Fµν :σannv�χχ→2γ ≃
4m4χ
πΛ6 , σ(e+e−→ χχγ)∼ s2
Λ6
Fermi γ-ray line signal ⇐⇒ mχ ≃ 130 GeV, Λ∼ 1 TeV
For complex scalar DM, consider OS =1
Λ2χ∗χFµν Fµν :
σannv�χχ∗→2γ ≃
2m2χ
πΛ4 , σ(e+e−→ χχ∗γ)∼ s
Λ4
Fermi γ-ray line signal ⇐⇒ mχ ≃ 130 GeV, Λ∼ 3 TeV
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 20 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Collider sensitivity
In the γ+ /E searching channel, the main background is e+e−→ ννγ:
e
Z0
e−
e+
ν
ν
γ
W
e
e−
e+
ν
ν
γ
W
W
e−
e+
ν
γ
ν
· · ·
Minor backgrounds: e+e−→ e+e−γ, e+e−→ τ+τ−γ, · · ·Simulation: FeynRules → MadGraph 5 → PGS 4
ILD-like ECAL energy resolution:∆E
E=
16.6%pE/GeV
⊕ 1.1%
Future e+e− colliders: ps = 250 GeV (“Higgs factory”),ps = 500 GeV (typical ILC), ps = 1 TeV (upgraded ILC & initial CLIC),ps = 3 TeV (ultimate CLIC)
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 21 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Collider sensitivityd
σ /
θγ
(f
b /
de
gre
e)
θγ
e+e
− collider, √s = 500 GeV, γ + E ⁄
e+e
− → νν−γ
e+e
− → e
+e
−γFermionic DM
Scalar DM
10-2
10-1
100
101
102
0° 20° 40° 60° 80° 100° 120° 140° 160° 180°
dσ
/ p
Tγ (
fb /
Ge
V)
pTγ (GeV)
e+e
− collider, √s = 500 GeV, γ + E ⁄
e+e
− → νν−γ
e+e
− → e
+e
−γFermionic DM
Scalar DM
10-2
10-1
100
101
102
0 50 100 150 200 250
dσ
/ m
mis
s
(fb
/ G
eV
)
mmiss = [ ( pe− + pe
+ − pγ )2 ]1/2
(GeV)
e+e
− collider, √s = 500 GeV, γ + E ⁄
e+e
− → νν−γ
e+e
− → e
+e
−γFermionic DM
Scalar DM
10-2
10-1
100
101
102
0 100 200 300 400 500
Z0 pole
Cut 1 (pre-selection):Require a photon with Eγ > 10 GeVand 10◦ < θγ < 170◦Veto any other particle
Benchmark point: Λ = 200 GeV, mχ = 100 (50)GeV for fermionic (scalar) DM
Cut 2: Veto 50 GeV< mmiss < 130 GeV
Cut 3: Require 30◦ < θγ < 150◦
Cut 4: Require pγT >p
s/10
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 22 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Collider sensitivityd
σ /
θγ
(f
b /
de
gre
e)
θγ
e+e
− collider, √s = 500 GeV, γ + E ⁄
e+e
− → νν−γ
e+e
− → e
+e
−γFermionic DM
Scalar DM
10-2
10-1
100
101
102
0° 20° 40° 60° 80° 100° 120° 140° 160° 180°
dσ
/ p
Tγ (
fb /
Ge
V)
pTγ (GeV)
e+e
− collider, √s = 500 GeV, γ + E ⁄
e+e
− → νν−γ
e+e
− → e
+e
−γFermionic DM
Scalar DM
10-2
10-1
100
101
102
0 50 100 150 200 250
dσ
/ m
mis
s
(fb
/ G
eV
)
mmiss = [ ( pe− + pe
+ − pγ )2 ]1/2
(GeV)
e+e
− collider, √s = 500 GeV, γ + E ⁄
e+e
− → νν−γ
e+e
− → e
+e
−γFermionic DM
Scalar DM
10-2
10-1
100
101
102
0 100 200 300 400 500
Z0 pole
Cut 1 (pre-selection):Require a photon with Eγ > 10 GeVand 10◦ < θγ < 170◦Veto any other particle
Benchmark point: Λ = 200 GeV, mχ = 100 (50)GeV for fermionic (scalar) DM
Cut 2: Veto 50 GeV< mmiss < 130 GeV
Cut 3: Require 30◦ < θγ < 150◦
Cut 4: Require pγT >p
s/10
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 22 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Collider sensitivityd
σ /
θγ
(f
b /
de
gre
e)
θγ
e+e
− collider, √s = 500 GeV, γ + E ⁄
e+e
− → νν−γ
e+e
− → e
+e
−γFermionic DM
Scalar DM
10-2
10-1
100
101
102
0° 20° 40° 60° 80° 100° 120° 140° 160° 180°
dσ
/ p
Tγ (
fb /
Ge
V)
pTγ (GeV)
e+e
− collider, √s = 500 GeV, γ + E ⁄
e+e
− → νν−γ
e+e
− → e
+e
−γFermionic DM
Scalar DM
10-2
10-1
100
101
102
0 50 100 150 200 250
dσ
/ m
mis
s
(fb
/ G
eV
)
mmiss = [ ( pe− + pe
+ − pγ )2 ]1/2
(GeV)
e+e
− collider, √s = 500 GeV, γ + E ⁄
e+e
− → νν−γ
e+e
− → e
+e
−γFermionic DM
Scalar DM
10-2
10-1
100
101
102
0 100 200 300 400 500
Z0 pole
Cut 1 (pre-selection):Require a photon with Eγ > 10 GeVand 10◦ < θγ < 170◦Veto any other particle
Benchmark point: Λ = 200 GeV, mχ = 100 (50)GeV for fermionic (scalar) DM
Cut 2: Veto 50 GeV< mmiss < 130 GeV
Cut 3: Require 30◦ < θγ < 150◦
Cut 4: Require pγT >p
s/10
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 22 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Collider sensitivityd
σ /
θγ
(f
b /
de
gre
e)
θγ
e+e
− collider, √s = 500 GeV, γ + E ⁄
e+e
− → νν−γ
e+e
− → e
+e
−γFermionic DM
Scalar DM
10-2
10-1
100
101
102
0° 20° 40° 60° 80° 100° 120° 140° 160° 180°
dσ
/ p
Tγ (
fb /
Ge
V)
pTγ (GeV)
e+e
− collider, √s = 500 GeV, γ + E ⁄
e+e
− → νν−γ
e+e
− → e
+e
−γFermionic DM
Scalar DM
10-2
10-1
100
101
102
0 50 100 150 200 250
dσ
/ m
mis
s
(fb
/ G
eV
)
mmiss = [ ( pe− + pe
+ − pγ )2 ]1/2
(GeV)
e+e
− collider, √s = 500 GeV, γ + E ⁄
e+e
− → νν−γ
e+e
− → e
+e
−γFermionic DM
Scalar DM
10-2
10-1
100
101
102
0 100 200 300 400 500
Z0 pole
Cut 1 (pre-selection):Require a photon with Eγ > 10 GeVand 10◦ < θγ < 170◦Veto any other particle
Benchmark point: Λ = 200 GeV, mχ = 100 (50)GeV for fermionic (scalar) DM
Cut 2: Veto 50 GeV< mmiss < 130 GeV
Cut 3: Require 30◦ < θγ < 150◦
Cut 4: Require pγT >p
s/10
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 22 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Collider sensitivity
Cross sections and signal significances after each cutννγ e+e−γ Fermionic DM Scalar DMσ (fb) σ (fb) σ (fb) S/
pB σ (fb) S/
pB
Cut 1 2415.2 173.0 646.8 12.7 321.4 6.3Cut 2 2102.5 168.6 646.8 13.6 308.2 6.5Cut 3 1161.1 16.8 538.0 15.7 255.9 7.5Cut 4 254.5 1.9 520.7 32.5 253.9 15.8
Benchmark point: Λ = 200 GeV, mχ = 100 (50)GeV for fermionic (scalar) DM
Most of the signal events remaine+e−→ ννγ background: reduced by almost an order of magnitudee+e−→ e+e−γ background: only one percent survives
(ps = 500 GeV, 1 fb−1)
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 23 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Collider sensitivityΛ
(G
eV
)
mχ (GeV)
Fermionic DM
√s = 250 GeV
√s = 500 GeV
√s = 1 TeV
√s = 3 TeV
102
103
104
5 50 500 10 100 1000
Fermi γ -ray line signal
Λ (G
eV
)
mχ (GeV)
Scalar DM
√s = 250 GeV
√s = 500 GeV
√s = 1 TeV
√s = 3 TeV
102
103
104
5 50 500 10 100 1000
Fermi γ -ray line signal
< σ
an
nv >
(c
m3 s
-1)
mχ (GeV)
Fermionic DM
√s = 250 GeV
√s = 500 GeV
√s = 1 TeV
√s = 3 TeV
Fermi 3.7-year upper limit
10-35
10-34
10-33
10-32
10-31
10-30
10-29
10-28
10-27
10-26
10-25
10-24
10-23
10-22
5 50 500 10 100 1000
Fermi γ -ray line signal
< σ
an
nv >
(c
m3 s
-1)
mχ (GeV)
Scalar DM
√s = 250 GeV
√s = 500 GeV
√s = 1 TeV
√s = 3 TeV
Fermi 3.7-year upper limit
10-31
10-30
10-29
10-28
10-27
10-26
10-25
10-24
10-23
10-22
5 50 500 10 100 1000
Fermi γ -ray line signal
Solid lines: 100 fb−1; dot-dashed lines: 1000 fb−1 (S/p
B = 3)[ZHY, Yin, Yan, arXiv:1307.5740]
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 24 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Beam polarization
Beam polarizationFor a process at an e+e− collider with polarized beams,σ(Pe− , Pe+) =
14
�(1+ Pe−)(1+ Pe+)σRR+ (1− Pe−)(1− Pe+)σLL
+(1+ Pe−)(1− Pe+)σRL+ (1− Pe−)(1+ Pe+)σLR�
Positro
n p
ola
rization P
e+
Electron polarization Pe−
σ (e+e
− → νν
−γ ) [fb]
-1.0
-1.0
-0.5
0.0
0.5
1.0
-1.0 -0.5 0.0 0.5 1.0
8000
6000
4400
3000
2000
1200
750
500
500
Positro
n p
ola
rization P
e+
Electron polarization Pe−
σ (e+e
− → χχ
−γ ) [fb], fermionic DM
-1.0
-1.0
-0.5
0.0
0.5
1.0
-1.0 -0.5 0.0 0.5 1.0
250
250
400
400
540
540
640
640700
700
800
800
940
940
1100
1100
Positro
n p
ola
rization P
e+
Electron polarization Pe−
σ (e+e
− → χχ*γ ) [fb], scalar DM
-1.0
-1.0
-0.5
0.0
0.5
1.0
-1.0 -0.5 0.0 0.5 1.0
120
120
200
200
270
270
320
320350
350
400
400
470
470
550
550
▲ (Pe− , Pe+) = (0.8,−0.3) can be achieved at the ILC[ILC technical design report, Vol. 1, 1306.6327]
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 25 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Beam polarization<
σa
nnv >
(c
m3 s
-1)
mχ (GeV)
Fermionic DM
Unpolarized, 200 fb-1
Unpolarized, 2000 fb-1
(Pe−, Pe
+) = (0.8, −0.3), 200 fb-1
(Pe−, Pe
+) = (0.8, −0.3), 2000 fb-1
Fermi 3.7-year upper limit
10-33
10-32
10-31
10-30
10-29
10-28
10-27
10-26
10-25
10-24
10-23
5 50 500 10 100 1000
Fermi γ -ray line signal
√s = 1 TeV
< σ
an
nv >
(c
m3 s
-1)
mχ (GeV)
Scalar DM
Unpolarized, 100 fb-1
Unpolarized, 1000 fb-1
(Pe−, Pe
+) = (0.8, −0.3), 100 fb-1
(Pe−, Pe
+) = (0.8, −0.3), 1000 fb-1
Fermi 3.7-year upper limit
10-31
10-30
10-29
10-28
10-27
10-26
10-25
10-24
10-23
5 50 500 10 100 1000
Fermi γ -ray line signal
√s = 3 TeV
(S/p
B = 3)
Using the polarized beams is roughly equivalent to increasing theintegrated luminosity by an order of magnitude.
For fermionic DM (scalar DM), a data set of 2000 fb−1 (1000 fb−1)would be just sufficient to test the Fermi γ-ray line signal at an e+e−collider with ps = 1 TeV (3 TeV).
[ZHY, Yin, Yan, arXiv:1307.5740]
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 26 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Mono-Z signature
Mono-Z signature: DM couplings to Z Z/Zγ
.
......
Z/γ
e−
e+
χ
χ
ZWe consider the following couplings:
OF1 =1
Λ31
χχBµνBµν +
1
Λ32
χχW aµνW
aµν
⊃ χχ(GZZZµνZµν + GAZAµνZµν)
OF2 =1
Λ31
χ iγ5χBµν Bµν +
1
Λ32
χ iγ5χW aµνW
aµν
⊃ χ iγ5χ(GZZZµν Zµν + GAZAµν Zµν)
OFH =1
Λ3 χχ(DµH)†DµH
→ m2Z
2Λ3 χχZµZµ
GZZ ≡ sin2 θW
Λ31
+cos2 θW
Λ32
GAZ ≡ 2sinθW cosθW
�1
Λ32
− 1
Λ31
�
The mono-Z channel at high energy e+e− collider can be sensitive tothe DM coupling to Z Z/Zγ.
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 27 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Mono-Z signature
Mono-Z signature: DM couplings to electrons
.
......
e
e−
e+
Z
χ
χ
e
e−
e+
χ
χ
Z
This channel can also be sensitive to the DM coupling to electrons.
We consider the following couplings:
OFP =1
Λ2 χγ5χ eγ5e, OFA =1
Λ2 χγµγ5χ eγµγ5e
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 28 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Event distributions
Lepton channel: Z → ℓ+ℓ− (ℓ= e,µ)
SM backgrounds: e+e−→ ℓ+ℓ−νν , e+e−→ τ+τ−, e+e−→ τ+τ−νν
Reconstructing the Z boson: require only 2 leptons (e’s or µ’s) withpT > 10 GeV and |η|< 3, and that they are opposite-sign same-flavor;require their invariant mass satisfying |mℓℓ−mZ |< 5 GeV.Reconstructing the recoil mass: mrecoil =
p(pe+ + pe− − pℓ1 − pℓ2)
2;veto the events with mrecoil < 140 GeV.
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 29 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Event distributions
Lepton channel: Z → ℓ+ℓ− (ℓ= e,µ)D
iffe
ren
tia
l cro
ss s
ectio
n (
fb /
Ge
V)
mll (GeV)
e+e
− collider, √s = 500 GeV, ll + E ⁄
llνν
ττ
ττνν
F1
F2
FH
FP
FA
10-5
10-4
10-3
10-2
10-1
100
101
0 100 200 300 400 500 600
SM backgrounds: e+e−→ ℓ+ℓ−νν , e+e−→ τ+τ−, e+e−→ τ+τ−ννReconstructing the Z boson: require only 2 leptons (e’s or µ’s) withpT > 10 GeV and |η|< 3, and that they are opposite-sign same-flavor;
require their invariant mass satisfying |mℓℓ−mZ |< 5 GeV.Reconstructing the recoil mass: mrecoil =
p(pe+ + pe− − pℓ1 − pℓ2)
2;veto the events with mrecoil < 140 GeV.
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 29 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Event distributions
Lepton channel: Z → ℓ+ℓ− (ℓ= e,µ)D
iffe
ren
tia
l cro
ss s
ectio
n (
fb /
Ge
V)
mll (GeV)
e+e
− collider, √s = 500 GeV, ll + E ⁄
llνν
ττ
ττνν
F1
F2
FH
FP
FA
10-5
10-4
10-3
10-2
10-1
100
101
0 100 200 300 400 500 600
SM backgrounds: e+e−→ ℓ+ℓ−νν , e+e−→ τ+τ−, e+e−→ τ+τ−ννReconstructing the Z boson: require only 2 leptons (e’s or µ’s) withpT > 10 GeV and |η|< 3, and that they are opposite-sign same-flavor;require their invariant mass satisfying |mℓℓ−mZ |< 5 GeV.
Reconstructing the recoil mass: mrecoil =p(pe+ + pe− − pℓ1 − pℓ2)
2;veto the events with mrecoil < 140 GeV.
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 29 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Event distributions
Lepton channel: Z → ℓ+ℓ− (ℓ= e,µ)D
iffe
ren
tia
l cro
ss s
ectio
n (
fb /
Ge
V)
mll (GeV)
e+e
− collider, √s = 500 GeV, ll + E ⁄
llνν
ττ
ττνν
F1
F2
FH
FP
FA
10-5
10-4
10-3
10-2
10-1
100
101
0 100 200 300 400 500 600
Diffe
ren
tia
l cro
ss s
ectio
n (
fb /
Ge
V)
mrecoil (GeV)
e+e
− collider, √s = 500 GeV, ll + E ⁄
llνν
ττ
ττνν
F1
F2
FH
FP
FA
10-5
10-4
10-3
10-2
10-1
100
0 100 200 300 400 500
SM backgrounds: e+e−→ ℓ+ℓ−νν , e+e−→ τ+τ−, e+e−→ τ+τ−ννReconstructing the Z boson: require only 2 leptons (e’s or µ’s) withpT > 10 GeV and |η|< 3, and that they are opposite-sign same-flavor;require their invariant mass satisfying |mℓℓ−mZ |< 5 GeV.Reconstructing the recoil mass: mrecoil =
p(pe+ + pe− − pℓ1 − pℓ2)
2;
veto the events with mrecoil < 140 GeV.
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 29 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Event distributions
Lepton channel: Z → ℓ+ℓ− (ℓ= e,µ)D
iffe
ren
tia
l cro
ss s
ectio
n (
fb /
Ge
V)
mll (GeV)
e+e
− collider, √s = 500 GeV, ll + E ⁄
llνν
ττ
ττνν
F1
F2
FH
FP
FA
10-5
10-4
10-3
10-2
10-1
100
101
0 100 200 300 400 500 600
Diffe
ren
tia
l cro
ss s
ectio
n (
fb /
Ge
V)
mrecoil (GeV)
e+e
− collider, √s = 500 GeV, ll + E ⁄
llνν
ττ
ττνν
F1
F2
FH
FP
FA
10-5
10-4
10-3
10-2
10-1
100
0 100 200 300 400 500
SM backgrounds: e+e−→ ℓ+ℓ−νν , e+e−→ τ+τ−, e+e−→ τ+τ−ννReconstructing the Z boson: require only 2 leptons (e’s or µ’s) withpT > 10 GeV and |η|< 3, and that they are opposite-sign same-flavor;require their invariant mass satisfying |mℓℓ−mZ |< 5 GeV.Reconstructing the recoil mass: mrecoil =
p(pe+ + pe− − pℓ1 − pℓ2)
2;veto the events with mrecoil < 140 GeV.
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 29 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Event distributions
Hadron channel: Z → j j
SM backgrounds: e+e−→ j jνν , e+e−→ j jℓν , e+e−→ t t
Reconstructing the Z boson: require only 2 jets with pT > 10 GeV and|η|< 3; require their invariant mass satisfying 40 GeV< m j j < 95 GeV.
Reconstructing the recoil mass: mrecoil =p(pe+ + pe− − p j1 − p j2)
2;veto the events with mrecoil < 200 GeV.
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 30 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Event distributions
Hadron channel: Z → j jD
iffe
ren
tia
l cro
ss s
ectio
n (
fb /
Ge
V)
mjj (GeV)
e+e
− collider, √s = 500 GeV, jj + E ⁄
jjνν
jjlν
tt
F1
F2
FH
FP
FA
10-4
10-3
10-2
10-1
100
101
0 100 200 300 400 500 600
SM backgrounds: e+e−→ j jνν , e+e−→ j jℓν , e+e−→ t t
Reconstructing the Z boson: require only 2 jets with pT > 10 GeV and|η|< 3;
require their invariant mass satisfying 40 GeV< m j j < 95 GeV.
Reconstructing the recoil mass: mrecoil =p(pe+ + pe− − p j1 − p j2)
2;veto the events with mrecoil < 200 GeV.
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 30 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Event distributions
Hadron channel: Z → j jD
iffe
ren
tia
l cro
ss s
ectio
n (
fb /
Ge
V)
mjj (GeV)
e+e
− collider, √s = 500 GeV, jj + E ⁄
jjνν
jjlν
tt
F1
F2
FH
FP
FA
10-4
10-3
10-2
10-1
100
101
0 100 200 300 400 500 600
SM backgrounds: e+e−→ j jνν , e+e−→ j jℓν , e+e−→ t t
Reconstructing the Z boson: require only 2 jets with pT > 10 GeV and|η|< 3; require their invariant mass satisfying 40 GeV< m j j < 95 GeV.
Reconstructing the recoil mass: mrecoil =p(pe+ + pe− − p j1 − p j2)
2;veto the events with mrecoil < 200 GeV.
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 30 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Event distributions
Hadron channel: Z → j jD
iffe
ren
tia
l cro
ss s
ectio
n (
fb /
Ge
V)
mjj (GeV)
e+e
− collider, √s = 500 GeV, jj + E ⁄
jjνν
jjlν
tt
F1
F2
FH
FP
FA
10-4
10-3
10-2
10-1
100
101
0 100 200 300 400 500 600
Fra
ctio
n o
f e
ve
nts
mrecoil (GeV)
e+e
− collider, √s = 500 GeV, jj + E ⁄
jjνν
jjlν
tt
F1
F2
FH
FP
FA
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
0 100 200 300 400 500
SM backgrounds: e+e−→ j jνν , e+e−→ j jℓν , e+e−→ t t
Reconstructing the Z boson: require only 2 jets with pT > 10 GeV and|η|< 3; require their invariant mass satisfying 40 GeV< m j j < 95 GeV.
Reconstructing the recoil mass: mrecoil =p(pe+ + pe− − p j1 − p j2)
2;
veto the events with mrecoil < 200 GeV.
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 30 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Event distributions
Hadron channel: Z → j jD
iffe
ren
tia
l cro
ss s
ectio
n (
fb /
Ge
V)
mjj (GeV)
e+e
− collider, √s = 500 GeV, jj + E ⁄
jjνν
jjlν
tt
F1
F2
FH
FP
FA
10-4
10-3
10-2
10-1
100
101
0 100 200 300 400 500 600
Fra
ctio
n o
f e
ve
nts
mrecoil (GeV)
e+e
− collider, √s = 500 GeV, jj + E ⁄
jjνν
jjlν
tt
F1
F2
FH
FP
FA
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
0.090
0.100
0 100 200 300 400 500
SM backgrounds: e+e−→ j jνν , e+e−→ j jℓν , e+e−→ t t
Reconstructing the Z boson: require only 2 jets with pT > 10 GeV and|η|< 3; require their invariant mass satisfying 40 GeV< m j j < 95 GeV.
Reconstructing the recoil mass: mrecoil =p(pe+ + pe− − p j1 − p j2)
2;veto the events with mrecoil < 200 GeV.
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 30 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Expected sensitivity
3σ sensitivity: DM couplings to Z Z/ZγΛ
(G
eV
)
mχ (GeV)
e+e
− collider, Operator F1
√s = 250 GeV, jj + E ⁄√s = 500 GeV, jj + E ⁄√s = 1 TeV, jj + E ⁄√s = 250 GeV, ll + E ⁄√s = 500 GeV, ll + E ⁄√s = 1 TeV, ll + E ⁄
101
102
103
5 50 500 1 10 100 1000
Λ
(Ge
V)
mχ (GeV)
e+e
− collider, Operator FH
√s = 250 GeV, jj + E ⁄√s = 500 GeV, jj + E ⁄√s = 1 TeV, jj + E ⁄√s = 250 GeV, ll + E ⁄√s = 500 GeV, ll + E ⁄√s = 1 TeV, ll + E ⁄
101
102
5 50 500 1 10 100 1000
Λ
(Ge
V)
mχ (GeV)
e+e
− collider, Operator F2
√s = 250 GeV, jj + E ⁄√s = 500 GeV, jj + E ⁄√s = 1 TeV, jj + E ⁄√s = 250 GeV, ll + E ⁄√s = 500 GeV, ll + E ⁄√s = 1 TeV, ll + E ⁄
101
102
103
5 50 500 1 10 100 1000
< σ
an
nv >
(c
m3 s
-1)
mχ (GeV)
χχ− → ZZ, Operator F2
√s = 500 GeV
√s = 1 TeV
Fermi 4-year upper limit
10-29
10-28
10-27
10-26
10-25
10-24
10-23
10-22
10-21
10-20
500 100 1000
(with an integrated luminosity of 1000 fb−1, assuming Λ = Λ1 = Λ2 for OF1 and OF2)Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 31 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Expected sensitivity
3σ sensitivity: DM couplings to electronsΛ
(G
eV
)
mχ (GeV)
e+e
− collider, Operator FP
√s = 250 GeV, jj + E ⁄√s = 500 GeV, jj + E ⁄√s = 1 TeV, jj + E ⁄√s = 250 GeV, ll + E ⁄√s = 500 GeV, ll + E ⁄√s = 1 TeV, ll + E ⁄
101
102
103
5 50 500 1 10 100 1000
< σ
an
nv >
(c
m3 s
-1)
mχ (GeV)
χχ− → e+e
−, Operator FP
√s = 250 GeV
√s = 500 GeV
√s = 1 TeV
Fermi 4-year upper limit
10-31
10-30
10-29
10-28
10-27
10-26
10-25
10-24
10-23
10-22
5 50 500 1 10 100 1000
Λ
(Ge
V)
mχ (GeV)
e+e
− collider, Operator FA
√s = 250 GeV, jj + E ⁄√s = 500 GeV, jj + E ⁄√s = 1 TeV, jj + E ⁄√s = 250 GeV, ll + E ⁄√s = 500 GeV, ll + E ⁄√s = 1 TeV, ll + E ⁄
101
102
103
5 50 500 1 10 100 1000
(with an integrated luminosity of 1000 fb−1)Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 32 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Conclusions and discussions
...1 As a frontier of cosmology, astrophysics, and particle physics, theresearch of dark matter connects our knowledge of the Universefrom the largest to the smallest scales.
...2 In addition to DM direct and indirect detection, collider detectionprovides an independent and complementary way to explore themicroscopic nature of DM particles.
...3 If there are other new particles accompanied with DM particles,collider detection is needed to acquire the most detailedinformation about the new physics containing DM particles.
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 33 / 34
. . . . . . . .Dark matter
. . . . . .Collider detection
. . . . . . . . . . .Monophoton signature
. . . . . .Mono-Z signature
. .Conclusions
Thanks for your attentions!
Zhao-Huan YU (IHEP) Dark matter searches at high energy colliders Dec 2013 34 / 34