Dark Matters

WestCoast UCR 17 April 2009

Dark Matters

Graham Kribs University of Oregon

Evidence for Dark Matter: Overwhelming Nucleosynethesis Rotation Curves Structure Formation

Weak Lensing CMB BAO

Dark Matter: New Physics Not about: • • • • •

Tuning Fine-fining Beauty Aesthetics ...

It’s real new physics, waiting to be discovered!

We don’t know:

Mass of Dark Matter Composition of Dark Matter Interactions of Dark Matter

We do know: 1) Dark matter is dark 2) ρDM ≈ 5 ρmatter (averaging over Universe) 3) Dark matter is cold (well, not hot)

What to make of ρDM ≈ 5ρmatter? 1) Coincidence (axions, etc.) 2) Dark matter “number” related to baryon number, asymmetry! 3) Weak scale inspired coincidence (WIMPs)

1 pb 2 Ωh ≈ 0.1 ———

andidate electron events (162,000) with energy over 50 GeV are plotted as a stogram with the horizontal axis showing the sum of the ‘weighted energy action’ (F values as defined below) in the last two BGO layers and the ower width (root mean squared, r.m.s.) in the first two layers. The shower dth is calculated as

Figure 2 | ATIC-1 and ATIC-2 spectra at balloon altitude, showing good agreement with each other. The measured primary electron flux (scaled by E3) at flight altitude is shown for ATIC-1 (open squares) and ATIC-2 (filled circles). The errors are one standard deviation. Both balloon flights were from McMurdo, Antarctica, and circumnavigated that continent. ATIC-1 was a test flight in 2000–01 and the usable data correspond to an exposure of 2-4 keV 0.61 m2 sr days. ATIC-2 was a science flight in 2002–03 with an exposure of 2.47 m2 sr days. To eliminate edge effects, we restrict the incident zenith DAMA/NaI (0.29 ton!yr) DAMA/LIBRA (0.53 ton!yr) angle to be less than ,37u (cos h $ 0.8), use only the central 80% of the SiM (targetouter mass = 87.3crystals kg) (targetlayer. mass = 232.8 kg) these and eliminate events in the in each BGO Within limits, the electron detection efficiency above 60 GeV is 84% essentially independent of energy. The effective acceptance was determined as a function of particle energy considering the trigger efficiency, trajectory reconstruction efficiency and the geometrical restrictions. The effective acceptance of the instrument increases from 0.075 m2 sr at 20 GeV to 0.15 m2 sr for E . 60 GeV. Above 100 GeV, a total of 1,724 electron events were observed, with the highest energy event at 2.3 TeV. The total background is also shown in the figure as the open triangles and is a combination of unresolved protons, unidentified c-rays and atmospheric secondary electrons produced in the material (,4.5 g cm22) above the instrument. ATIC becomes background limited for electrons only above several teraelectronvolts.

i~1

2

Ei ðXi { Xc Þ =

n X

Ei

i~1

+

here Xc is the coordinate of the energy centre, Xi is the coordinate of the 0.2 ntre of the ith crystal and Ei is the energy deposited in the ith crystal. The F lue is calculated as Fn ~ðEn =SumÞ hr:m:s:i2 where En is the energy deposit BGO layer n,0.1Sum isMuller the& total energy deposit in all BGO layers and Ær.m.s.æ Tang 1987 fers to layer n (ref. 12). Each event is also fitted to an electromagnetic MASS 1989 scade profile to estimate the starting point and the depth of the cascade TS93 HEAT94+95 aximum. An event is accepted if the cascade starts above the first BGO CAPRICE94 yer, which eliminates many protons (,75%) but passes most electrons AMS98 ,90%). Next a diagonal cut in r.m.s. and F is determined for each energy n and used 0.02 to isolateHEAT00 the electrons. This removes most of the protons (2 in Clem & Evenson 2007 4 remain) and retains 84% of the electrons12. The selected electrons are PAMELA own as the dotted histogram. 0.01 0.1

1

10

100

Energy (GeV)

part from the calculated curve. They show an excess electron flux p to about 650 GeV,positron abovefraction whichwith theother spectrum drops rapidly, with a FIG. 3: PAMELA experimental data. The positron fraction the PAMELA experimentline compared with other recentIn experimental data[24, 29, 30, turnmeasured to the by ‘general’ spectrum at ,800 GeV. particular, over 31, 32, 33, 34, 35]. One to standard error bars are shown. not visible, they lie inside the e energy range 300 800 deviation GeV we observe 210 Ifelectrons, whereas data points. ALPROP predicts only 140 events, an excess of about six standard viations. a source-on/source-off method determining a showerUsing tail catcher scintillator (S4) and a neutron detector. for The ToF system provides 15 a fast signal, for acquisition and measures the standard time-of-flightdeviaand ionizagnificance’ wetriggering obtaintheandata excess of roughly four tion energy losses (dE/dx) of traversing section particles. 4). It also allows down-going particles to ons (Supplementary Information reliably identified. Multiple tracks, produced in interactions above the spectrometer, Databe recently became available from the Polar Patrol Balloon were rejected by requiring that only one strip of the top ToF scintillator (S1 and S2) layers Antarctic) flight of the BETS detector. Although of lower statistical registered an energy deposition (’hit’). Similarly no hits were permitted in either top scintilecision, results from the PPB-BETS calorimeter16 also indicate a lators of the AC system (CARD and CAT). The central part of the PAMELA apparatus is ossible structure and agree with the ATIC results (see Fig. 3), giving 12 dded confidence to the conclusion that this feature is real. We varied the source injection parameters in the GALPROP code try to reproduce the data points at 500 to 700 GeV. This required a ard injection spectrum which could not reproduce the drop in flux

Residuals (cpd/kg/keV)

hr:m:s:i ~

n X

Time (day)

2-5 keV

1,000 Residuals (cpd/kg/keV)

0.3

2

Ee3.0dN/dEe (m−2 s−1 sr−1 GeV2)

0.4

+

-

Positron fraction !(e ) / (!(e )+ !(e ))

Some Intriguing Hints...

DAMA/NaI (0.29 ton!yr) (target mass = 87.3 kg)

DAMA/LIBRA (0.53 ton!yr) (target mass = 232.8 kg)

100

10

10

100 Energy (GeV)

1,000

Time (day)

Main Focus: PAMELA antiproton fraction -3

0.4

!10

0.4 0.3

0.35

0.2

0.3

Donato 2001 (D, " =500MV) Simon 1998 (LBM, " =500MV) Ptuskin 2006 (PD, " =550MV) PAMELA

+

+

-

Positron fraction !(e ) / (!(e )+ !(e ))

positron fraction

0.02

0.25 Muller & Tang 1987

p/p

0.1

MASS 1989 TS93 HEAT94+95

0.15

CAPRICE94 AMS98

0.1

HEAT00 Clem & Evenson 2007

0.05

PAMELA

0.01 0.1

0.2

1

10

100

Energy (GeV)

0 1

10 kinetic energy (GeV)

102

G. 3: PAMELA positron fraction with other experimental data. The positron fraction

FIG. 3: The antiproton-to-proton flux ratio obtained in this work com PAMELA

asured by the PAMELA experiment compared with other recent experimental data[24, 29, 30,

32, 33, 34, 35]. One standard deviation error bars are shown. If not visible, they lie inside the

a points.

These hints (signals & no signals) strongly disfavor the MSSM neutralino

These hints (positive and negative) strongly disfavor the MSSM neutralino Motivating various theorists to theorize...

Results

Post-PAMELA Which DM can fitpapers... the data? M.Pospelov and A.Ritz, 0810.1502: Secluded DM - A.Nelson and C.Spitzer, 0810.5167: Slightly Non-Minimal DM - Y.Nomura and J.Thaler, 0810.5397: DM through the Axion Portal - R.Harnik and G.Kribs, 0810.5557: Dirac DM - D.Feldman, Z.Liu, P.Nath, 0810.5762: Hidden Sector - T.Hambye, 0811.0172: Hidden Vector - Yin, Yuan, Liu, Zhang, Bi, Zhu, 0811.0176: Leptonically decaying DM - K.Ishiwata, S.Matsumoto, T.Moroi, 0811.0250: Superparticle DM - Y.Bai and Z.Han, 0811.0387: sUED DM - P.Fox, E.Poppitz, 0811.0399: Leptophilic DM - C.Chen, F.Takahashi, T.T.Yanagida, 0811.0477: Hidden-Gauge-Boson DM - K.Hamaguchi, E.Nakamura, S.Shirai, T.T.Yanagida, 0811.0737: Decaying DM in Composite Messenger - E.Ponton, L.Randall, 0811.1029: Singlet DM - A.Ibarra, D.Tran, 0811.1555: Decaying DM - S.Baek, P.Ko, 0811.1646: U(1) Lmu-Ltau DM - C.Chen, F.Takahashi, T.T.Yanagida, 0811.3357: Decaying Hidden-Gauge-Boson DM I.Cholis, G.Dobler, D.Finkbeiner, L.Goodenough, N.Weiner, 0811.3641: 700+ GeV WIMP - E.Nardi, F.Sannino, A.Strumia, 0811.4153: Decaying DM in TechniColor - K.Zurek, 0811.4429: Multicomponent DM - M.Ibe, H.Murayama, T.T.Yanagida, 0812.0072: Breit-Wigner enhancement of DM annihilation - E.Chun, J.-C.Park, 0812.0308: sub-GeV hidden U(1) in GMSB - M.Lattanzi, J.Silk, 0812.0360: Sommerfeld enhancement in cold substructures - M.Pospelov, M.Trott, 0812.0432: super-WIMPs decays DM - Zhang, Bi, Liu, Liu, Yin, Yuan, Zhu, 0812.0522: Discrimination with SR and IC - Liu, Yin, Zhu, 0812.0964: DMnu from GC - M.Pohl, 0812.1174: electrons from DM - J.Hisano, M.Kawasaki, K.Kohri, K.Nakayama, 0812.0219: DMnu from GC A.Arvanitaki, S.Dimopoulos, S.Dubovsky, P.Graham, R.Harnik, S.Rajendran, 0812.2075: Decaying DM in GUTs - R.Allahverdi, B.Dutta, K.Richardson-McDaniel, Y.Santoso, 0812.2196: SuSy B-L DM- S.Hamaguchi, K.Shirai, T.T.Yanagida, 0812.2374: Hidden-Fermion DM decays - D.Hooper, A.Stebbins, K.Zurek, 0812.3202: Nearby DM clump - C.Delaunay, P.Fox, G.Perez, 0812.3331: DMnu from Earth - Park, Shu, 0901.0720: SplitUED DM - .Gogoladze, R.Khalid, Q.Shafi, H.Yuksel, 0901.0923: cMSSM DM with additions - Q.H.Cao, E.Ma, G.Shaughnessy, 0901.1334: Dark Matter: the leptonic connection - E.Nezri, M.Tytgat, G.Vertongen, 0901.2556: Inert Doublet DM - C.-H.Chen, C.-Q.Geng, D.Zhuridov, 0901.2681: Fermionic decaying DM J.Mardon, Y.Nomura, D.Stolarski, J.Thaler, 0901.2926: Cascade annihilations (light non-abelian new bosons) - P.Meade, M.Papucci, T.Volansky, 0901.2925: DM sees the light - D.Phalen, A.Pierce, N.Weiner, 0901.3165: New Heavy Lepton - T.Banks, J.-F.Fortin, 0901.3578: Pyrma baryons - Goh, Hall, Kumar, 0902.0814: Leptonic Higgs - K.Bae, J.-H. Huh, J.Kim, B.Kyae, R.Viollier, 0812.3511: electrophilic axion from flipped-SU(5) with extra spontaneously broken symmetries and a two component DM with Z2 parity - ...

(from Cirelli; Moriond 09)

Four basic explanations: 1) PAMELA screwed up, e.g., misidentified positrons 4 (proton flux 10 times positron flux) 2) Point sources (pulsars, supernovae?) dumping more energy than previously thought into positrons 3) Dark matter annihilation 4) Dark matter decay

Four basic explanations: 1) PAMELA screwed up, e.g., misidentified positrons 4 (proton flux 10 times positron flux) 2) Point sources (pulsars, supernovae?) dumping more energy than previously thought into positrons 3) Dark matter annihilation 4) Dark matter decay

Interlude: Direct Detection of WIMPs

One of the most striking constraints on WIMPs is direct detection:

WIMP

Nucleus

WIMP

Nucleus

If the WIMP-nucleon coupling is coherent w.r.t. mass Generally expressed in terms of an effective nucleon cross section: σn

2 µ (n,D)

I(n) σ(N) ≈ ————————— ≈ ———— µ2(N,D) I(N) A4 [for M ≥ m(Nuc)]

That allows experiments with different materials to be compared (for c.w.r.t.m.) against each other

10-40

Direct Detection Bounds

10-41

σn

10-42 -43 10

Xenon 0706 CDMS 0802

10-44 -45 10

1995

2000

2005

2010

(adapted from Gaitskell 2004)

Original (1980s) hope for WIMPs

Acquire • mass from EWSB • coupling to SM through EW interactions e.g. fourth geneneration neutrino that acquires Dirac mass with ν4R

Such WIMPs have true Weak Interactions: Vector interactions to SM with GF strength: — — µ ν4 γ ν4 q γµ q ———————————— v2 Leads to WIMP-nucleon scattering cross section σn ≈ 0.1 pb!

(for ≈ 100 GeV WIMP)

s g . e e

-37 10 4 !41

Baltz Gondolo 2004 Roszkowski et al. 2007 95% CL Roszkowski et al. 2007 68% CL CDMS II 1T+2T Ge Reanalysis XENON10 2007 CDMS II 2008 Ge CDMS II Ge combined

2

Spin!independent cross section [cm ]

10

10

10

10

!42

Ruled Out by Direct Detection Bounds

!43

!44

10

1

2

10 WIMP mass [GeV/c2]

3

10

FIG. 4: Spin-independent WIMP-nucleon cross-section upper limits (90% C.L.) versus WIMP mass. The upper curve (dash-dot) is the result of a re-analysis [17] of our previously published data. The upper solid line is the limit from this

Direct Detection Suggests: • WIMPs coupling to quarks with sub-weak interaction strength (vector “g” ≤ 0.01; or Higgs exchange; or ...) or • WIMPs couple to leptons, not quarks (or gluons) Evades direct detection constraints. or • Not thermal freezeout (forget about 1 pb scale) or • ...

WIMPs Coupling to Leptons

New Dirac Fermion: D (Harnik, GK) • New Dirac fermion D neutral under SM gauge group • Global U(1)D conserved • Interactions with SM through higher dimensional operators -- effective theory! • Choose operators we want; discard those we don’t.

Higher Dimensional Operators _ DDff ————— 2 Λ We want: f = lepton (e) vector interaction no quarks

D _ D

f f

2 1/Λ

Thermally averaged cross section

= σ0 + σ2v2 + ... Dirac fermion:

2/Λ4 M ~

(not velocity suppressed)

D _ D

l l

2 1/Λ

Matching with thermal relic abundance: Ωh2 ≈ 0.1 (1 pb/) IV.

($.# 1

/0 /0 1 ! +0 +0

($."

!!!"#$%&

!

D _ D

(!.#

(!."

leptons only!

(".#

("." !""

!#"

$""

$#" %"" '(()*+,-

%#"

&""

A.l

POSITRON DIRA

Backgrou 2 1/Λ

Determining the b l is of utmost impor ratio excess does, in culation of the bac from the Galprop c ated as secondary p other protons and l the inputs to the c and parameter dep the uncertainties in Harnik,both GK sign propagate consistent way to t

Now onto indirect detection implications...

To make indirect DM annihilation predictions... Astrophysics Propagation: - diffusion - energy loss Backgrounds: - secondary production - pulsars (neglected) Abundance - average density - local clumpiness “BOOST factor”

Particle Physics - annihilation rate - annihilation channels Effective theory allows: + - annihilation into e e , - no other collider constraints (M > 100 GeV)!

Propagation Diffusion: charged particles move in galactic magnetic field modeled as a random walk. Models (convection; reacceleration); and fit to observations (B/C ratio...) Energy loss: light charged particles lose energy by synchrotron radiation & inverse Compton off starlight and CMB

We used “Galprop” [Moskolenko & Strong]. It requires as input, among other things: - proton (nuclei) spectrum - electron spectrum

For dark matter... Source

Propagated

while diffusion randomizes the direction. Typical scale for energy loss is ~ kpc, i.e., our galactic neighborhood.

Secondary production p

p, nuclei

+ π ->

+ e

... K+->μ+-> ... ->e+

Position and antiproton spectrum determined essentially by: input proton spectrum + propagation

PAMELA proton data

! ! y 2.75 r Proton flux * E a

in

e r P

m i l

(statistical errors only)

Power-law fit: ~ E-# # ~ 2.76

• Proton of primary origin • Diffusive shock-wave acceleration in SNRs • Local spectrum: injection spectrum ! galactic propagation

LBM

Local primary spectral shape: " study of particle acceleration mechanism

! Elena Vannuccini ! SSI 2008 !

Vannuccini SSI 08

na

i

Pr

im l e

!

! ry

Proton flux * E2.75


Power-law fit: ~ E-# # ~ 2.76


LBM



Galprop

Absolute secondary positron spectrum

Propagation: “best” of DC, DR, DRB; astro-ph/0502406 (Lionetto, Morselli, Zdravkovic)

-BETS data with an index of −2.77±0.21.

Observed

+

+ e)

flux

Tang 1984 Golden et al. 1984 Boezio et al. 2000 DuVernois et al. 2001 Torii et al. 2001 Aguilar et al. 2002 Kobayashi et al. 2002 Chang et al. 2005 This work

104 2

E3J (electrons m!2 s!1 sr!1 GeV )

(e

103

1.82"10!4(E/100GeV)!3.05

102

101 100

101

102 Electron Energy (GeV)

103

104

(from BETS paper)


4

2


10

103

Our approach (Oct 08)...

1.82"10!4(E/100GeV)!3.05

102

101 100

101


103

104

Fig. 12. Electron energy spectrum observed with PPB-BETS (solid circles) in comparison with the energy spectra of BETS (solid squares) ant the other observations. The dash line shows the best fit power-law function of the combined spectrum of PPB-BETS and BETS with an index of −3.05±0.05.

21

Absolute electron spectrum

(and use PAMELA flux ratio at 5 GeV to normalize e spectrum)


4

2


10

103

1.82"10!4(E/100GeV)!3.05

102

101 100

101


103

104


21


Which data to use?

PB-BETS data with an index of −2.77±0.21.

Electron data 5-100 GeV Tang 1984 Golden et al. 1984 Boezio et al. 2000 DuVernois et al. 2001 Torii et al. 2001 Aguilar et al. 2002 Kobayashi et al. 2002 Chang et al. 2005 This work

2


104

103

1.82"10!4(E/100GeV)!3.05

102

101 100

101


103

104

12. Electron energy spectrum observed with PPB-BETS (solid circles) in com-


Electron data 5-100 GeV Tang 1984 Golden et al. 1984 Boezio et al. 2000 DuVernois et al. 2001 Torii et al. 2001 Aguilar et al. 2002 Kobayashi Experiment et al. 2002 Chang et AMS-01 al. 2005 [29] This work

2


104

power law index α 3.15 ± 0.04 ATIC [30]!3.05 3.14 ± 0.08 1.82"10!4(E/100GeV) BETS [31, 32] 3.05 ± 0.05 CAPRICE [33] 3.47 ± 0.34 HEAT [34] 2.82 ± 0.16 MASS [35] 2.89 ± 0.10

103

102

101 100

101

12. Electron energy spectrum

TABLE I: Our weighted least-squares best fit to the flux, Φe− (E) ∝ E −α , measured by the various exp The BETS best fit was taken from [32]; their best 2 lower energy 3data between 10 the 10 10 104 to 100 GeV is 3. [31]; the error is assumed to be 1σ. The MASS best Electron Energy (GeV) from [35]; the error is assumed to be 1σ. We empha our reported errors for the other experiments are p (95% CL) with(solid regard circles) to fitting in data (wit observedtistical with PPB-BETS comto a power law, and do not necessarily reflect the i



2


104

power law index α 3.15 ± 0.04 ATIC [30]!3.05 3.14 ± 0.08 1.82"10!4(E/100GeV) BETS [31, 32] 3.05 ± 0.05 -2.8 CAPRICE [33] 3.47 ± 0.34 HEAT [34] 2.82 ± 0.16 -3.15 MASS [35] 2.89 ± 0.10

103

E E

102

-3.5 E

101 100

101

TABLE I: Our weighted least-squares best fit to the flux, Φe− (E) ∝ E −α , measured by the various exp The BETS best fit was taken from [32]; their best 2 lower energy 3data between 10 the 10 10 104 to 100 GeV is 3. [31]; the error is assumed to be 1σ. The MASS best Electron Energy (GeV) from [35]; the error is assumed to be 1σ. We empha our reported errors for the other experiments are p -2.8 -3.5 tistical (95% CL) with regard to fitting in data (wit observed with PPB-BETS (solid circles) comto a power law, and do not necessarily reflect the i

Interpretation:


E

> Φ(e) > E

Preliminary PAMELA Electron data

~ E- 3.24±0.04

Adriani; talk given in Waseda 14 Jan 09



2


104

power law index α 3.15 ± 0.04 ATIC [30]!3.05 3.14 ± 0.08 1.82"10!4(E/100GeV) BETS [31, 32] 3.05 ± 0.05 -2.8 CAPRICE [33] 3.47 ± 0.34 HEAT [34] 2.82 ± 0.16 -3.15 MASS [35] 2.89 ± 0.10

103

E E

102

-3.5 E

101 100

101

TABLE I: Our weighted least-squares best fit to the flux, Φe− (E) ∝ E −α , measured by the various exp The BETS best fit was taken from [32]; their best 2 lower energy 3data between 10 the 10 10 104 to 100 GeV is 3. [31]; the error is assumed to be 1σ. The MASS best Electron Energy (GeV) from [35]; the error is assumed to be 1σ. We empha our reported errors for the other experiments are p -2.8 -3.5 tistical (95% CL) with regard to fitting in data (wit observed with PPB-BETS (solid circles) comto a power law, and do not necessarily reflect the i

Interpretation:


E

> Φ(e) > E

Secondary production ONLY (no dark matter): Propagation models: convection reaccelaration reaccelaration+break

e /(e + e )

M PAMELA0.15 B ratio data

0.1 0.07

+

-3.5 E

0.1 0.07

Ratio derived 0.05 from: • e- data

0.05

+

+

+

−

e /(e + e )

0.15

0.2

−

0.2

E-3.15

• e+ predicted 0.03 secondary

0.03 -2.8 E

10

15 20

30

50

Energy (GeV)

70

100

Harnik, GK

a in


4

10 2



lim

!! y r Proton flux * E2.75 Power-law fit: ~ E-# # ~ 2.76



LBM

103

DM Annihilation

1.82"10!4(E/100GeV)!3.05

102

101 100

101


103

104


Galprop


Galprop

21

Absolute secondary positron spectrum


Spectrum from DM

M=100 GeV Dirac Dark Matter 0.2

+

0.1 0.07

+

−

e /(e + e )

M = 100 GeV 0.15 B = 1 (no boost)

0.05

0.03

100 Annihilation

to e+e- only

10

20

30

50

Energy (GeV)

100

200

Harnik, GK

Dirac Dark Matter: BOOST

BOOST = 1

BOOST = 5

for

for

α

2 M

M = 100 GeV -3.5 Φe- ≈ E ; ρlocal = 0.3 GeV/cm3 M = 100 GeV Φe- ≈ E-3.15; ρlocal = 0.3 GeV/cm3

be automatic. The relic abundance of an exa calculated before in Ref. [46] u channel) scalar exchange. Left scalars give rise to a four-fermio be Fierz transformed into our effe (5) with cL = (YL g ! )2 /2 and cR is the hypercharge of the Standa g ! is the hypercharge coupling. mass of the exchanged scalar Λ to immediately re-evaluate Fig. 1 of the physical scalar states that operators. This is shown in Fig. -3.15 of the leptonic The dominance efor two reasons. First, the four-fe 3pr Standard Model fermion are local much like KK dark matter [2, 3 the right-handed leptons. Secon scale as 1/m4f , even a modest hier are lighter than squarks will ove dominant annihilation channel to handed leptons. Hence, a Dirac annihilation to charged leptons. is clear: relatively light sleptons, about 200-400 GeV, are an ines obtain a thermal relic abundance ogy and a positron signal consist A pure Dirac bino-eigenstate Z. This eliminates one source o

M=100,200,400 GeV Dirac Dark Matter

0.2

M (GeV) 100 200 400

B 5 20 80

Φ ρ

0.1

+

+

−

e /(e + e )

0.5

0.05

10

20 30

50

100

Energy (GeV)

200

400

≈E ; = 0.3 GeV/cm

Lesson: Need enhancement FIG. 7: Same Fig. 6, for M = 100, 200, 400 GeV. The DCfor “heavy” DM model was used for propagation, and annihilation was assumed only (M into e » e .100 GeV) not “light” DM (M ≈ 100 GeV) + −

+ e

Feature in

e?

+

500

s ! e"#e$ ATIC 08 HESS 08

! !

200

!

E3 dN#dE !GeV2 m$2 s$1 sr$1 "

! !

! ! !

! !

!

!

!

! !

! !

" !

" "

100

! !

" "

50

" "

!

"

20

10

ADDGHR (adapted) 50

100

500 Energy !GeV"

1000

5000

Fermi/GLAST feature: FSR radiation D

f

_ D

- γ f

Size of signal *dependent* on DM density profile of galactic center

Mathev, Perelstein, Spray, umber ofBirkedal, signal (blue) and background (red) events at hep-ph/0507194 the GLAST space ion area A = 10000 cm2 , exposure time T = 2 years, field of view ∆Ω =

ependent of energy. The effective acceptance was determined as a ction of particle energy considering the trigger efficiency, trajectory onstruction efficiency and the geometrical restrictions. The effective eptance of the instrument increases from 0.075 m2 sr at 20 GeV to 5 m2 sr for E . 60 GeV. Above 100 GeV, a total of 1,724 electron events e observed, with the highest energy event at 2.3 TeV. The total kground is also shown in the figure as the open triangles and is a mbination of unresolved protons, unidentified c-rays and atmospheric ondary electrons produced in the material (,4.5 g cm22) above the trument. ATIC becomes background limited for electrons only above eral teraelectronvolts.

ATIC/PPB-BETS bump @ 500 GeV?

Ee3.0dN/dEe (m−2 s−1 sr−1 GeV2)

1,000

(Cannot be explained without BOOST factor or Sommerfeld or ...)

100

10

10

100 Energy (GeV)

1,000

ure 3 | ATIC results showing agreement with previous data at lower rgy and with the imaging calorimeter PPB-BETS at higher energy. The ctron differential energy spectrum measured by ATIC (scaled by E3) at the of the atmosphere (red filled circles) is compared with previous ervations from the Alpha Magnetic Spectrometer AMS (green stars)31, AT (open black triangles)30, BETS (open blue circles)32, PPB-BETS (blue sses)16 and emulsion chambers (black open diamonds)4,8,9, with certainties of one standard deviation. The GALPROP code calculates a wer-law spectral index of 23.2 in the low-energy region (solid curve)14. he dashed curve is the solar modulated electron spectrum and shows that

Fermi/GLAST will be definitive...

Dirac Bino as Dirac Dark Matter

Dirac Bino? Yes, the gauginos in low energy supersymmetry could acquire Dirac masses, not Majorana masses. This occurs when the gauginos are paired with new fermions (beyond MSSM) in the adjoint representation. Dirac masses are automatic in supersymmetric models that preserve an R-symmetry.

Interpretating D as a Dirac Bino Resolve the 4-fermion vertex as D _ D

f f

D _ D

f ~

f

f

The dominance of leptonic annihilation results automatically given YeR=1 and some mild hierarchy, m~l < m~q (and, dim-5 Higgs operator is absent)

Matching thermal relic abundance, = 1 pb 4"" 9

58 58 9 ! 18 18

#""

.5167*)+,-..++/0123

!

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%""

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Harnik, GK

Absence of Direct Detection (and no Antiproton Annihilation signal) Implies

D q

~ q

q D

cannot be large. Rough estimates of direct detection bounds suggest m~q > 1.5 TeV for first generation, right-handed squarks.

Also constraint on Higgsino content of LSP from direct detection D _ D

Z

f f

Our estimate, from (g’v)2/μ2 < 0.01, µ > 600 GeV

Sketch of Spectrum

~ dR

1.5 TeV

~ H

600 GeV

~ e

200 GeV 100 GeV

B

~~ µ,τ

~L ~ uL,d

~ uR

What’s unusual? R-symmetric models have very interesting flavor properties; much of the supersymmetric flavor problem is absent. With a Bino lighter than selectron, different from smuon/stau, suggests observable LFV (work in progress) In any case, sleptons become the prime targets for LHC...

Summary • Strong constraints and hints towards the particle nature of DM; MSSM in trouble. _ _• One pair D,D with DDll operator can: - thermally produce Ωh2 ≈ 0.1 relic abundance - avoid direct detection - explain PAMELA ratio with minimal boost factor - explain WMAP haze, right scale for DAMA, ... - can arise in R-symmetric (extended) SUSY • Collider implications of “unusual” dark matter candidates is only just beginning... stay tuned!