Shedding light on Dark Matter from accelerator physics

Transcription

1 Shedding light on Dark Matter from accelerator physics 17/11/ 11. UL-Bruxelles. based on Y. Mambrini, B.Z., hep-ph/ JCAP 11 (2011) 023

2 Overview Introduction Experimental evidences DM interpretations Nature of couplings Motivation Discussion & Results LEP vs Tevatron fermionic DM scalar DM combined analysis (astro+accel) universal lepton coupling pure electron coupling words on LHC Conclusions

3 Dark Matter in a nutshell

4 Dark Matter in a nutshell WMAP data: Ω X h 2 = ± % baryonic matter, 22% dark matter, 73% dark energy Boltzmann equation Ω X h 2 1 σv m2 X gx 4 WIMP miracle m X 0 GeV g g Weak σv 3 26 cm 3 /s. A priori requisites: weakly interacting, long-lived, neutral.

5 Dark excesses? (Acc. Exp., D.D ) CDF Collaboration [hep-ex/ ]

6 Dark excesses? (Acc. Exp., D.D) Many possibilities: Standard Model effect Stringy origin Technicolor 2-Higgs models etc hep-ph/11xx.xxx Sullivan et al, hep-ph/ Anchordoqui et al, hep-ph/ Eichten et al, hep-ph/ Chen et al, hep-ph/ Dark Matter interpretation e.g. Buckley et al, hep-ph/ dark Z-boson χ-nucleon scattering σ χ n 40 cm 2 (for m χ GeV) Hadrophilic coupling

7 Dark excesses? (Astro. Exp., D.D.) Fox et al, /hep-ph

8 Dark excesses? (Astro. Fox Exp., et al, /hep-ph D.D.) Tension in XENON and DAMA results electrophilic DM Bernabei et al, astro-ph/ DAMA sensible also to electron recoil leptophilic Fox et al, hep-ph/ hadrophilic Kopp et al, hep-ph/

9 Dark excesses? (Astro. Exp. I.D.) γ-rays observed by Fermi - inner parsecs unexplained - leptophilic DM Hooper et al, hep-ph/.2752

10 Dark excesses? (Astro. Exp. I.D.) e + -flux, by PAMELA - electrophilic, µ philic, π philic,... Cholis et al, astro-ph/

11 Motivation (LEP vs. Tevatron) Fox et al, hep-ph/ c O V = ( χγ µχ)( lγ µ l) Λ 2 O S = ( χχ)( ll) Λ 2 O A = ( χγ µγ 5 χ)( lγ µ γ 5 l) Λ 2 O t = ( χl)( lχ) Λ 2

12 Motivation (LEP vs. Tevatron) Fox et al, hep-ph/ c Fox et al, hep-ph/ O V = ( χγ µχ)( lγ µ l) Λ 2 O S = ( χχ)( ll) Λ 2 O A = ( χγ µγ 5 χ)( lγ µ γ 5 l) Λ 2 O t = ( χl)( lχ) Λ 2

13 Motivation (LEP vs. Tevatron) σ 1 loop = 4α2 µ 2 p 18 2 π 3 Λ 4 [ l f(q2, m l ) ] 2 Fox et al, hep-ph/ c (σv) S = 1 1 m2 l (m 2 8πΛ 4 m 2 χ m 2 l )vrel 2 χ

14 Motivation (LEP vs. Tevatron) Fox et al, hep-ph/ σ 1 loop = 4α2 µ 2 p 18 2 π 3 Λ 4 [ l f(q2, m l ) ] 2 c Fox et al, hep-ph/ (σv) S = 1 1 m2 l (m 2 8πΛ 4 m 2 χ m 2 l )vrel 2 χ

15 Motivation (LEP vs. Tevatron) c Luminosity of 1 fb 1

16 Motivation (LEP vs. Tevatron) Luminosity of 1 fb 1 c Bai et al, hep-ph/ Bai et al, hep-ph/

17 Motivation (LEP vs. Tevatron)

18 Motivation (LEP vs. Tevatron)

19 Motivation (LEP vs. Tevatron)

20 Motivation (LEP vs. Tevatron)

21 Motivation (LEP vs. Tevatron)

22 The Models Effective scales: Operators: L V = i L S = i L A = i 1 gl Λ l Λ ; 1 gh Λ h Λ gl i ( l i γ µ l i )( χγ Λ 2 µ χ) + gh i i ( q i γ µ q i )( χγ Λ 2 µ χ) gl i ( l i l i )( χχ) + g Λ 2 h i i ( q i q i )( χχ) Λ 2 gl i ( l i γ µ γ 5 l i )( χγ Λ 2 µ γ 5 χ) + gh i i ( q i γ µ γ 5 q i )( χγ Λ 2 µ γ 5 χ) L t = gl i i ( l i χ)( χl i ) + g Λ 2 h i i ( q i χ)( χq i ) Λ 2 Models in lepton sector: A) Electrophilic couplings: gl e = g e, g i=µ,τ,ν i l = 0 B) Charged lepton couplings: g i=e,µ,τ l = g l, g i=ν i l = 0 C) Universal lepton couplings: g i=e,µ,τ,ν i l = g l Universality in hadronic couplings: g i=u,d,c,s,b,t h = g h.

23 Annihilation cross-sections dσ I dω = M I 2 s 2m 2 3 2m2 4 + (m2 3 m2 4 )2 s 64π 2 s s 4m 2 χ ; s 4m 4 χ + m 2 χv 2 σ J I v = g 2 l σi,l J v+c g2 h σi,h J v l=e,µ,τ,ν h=u,d,c,s,t,b J: operator type I: coupling type σ V,k v = 4g Λ ( 24(2m 2 χ + m 2 k) + 8m4 χ 4m 2 χm 2 k + ) 5m4 k m 2 χ m 2 v 2 l σ S,k v = 24g Λ (m 2 χ m 2 k)v 2 ( σ A,k v = 4g Λ 24m 2 k + 8m4 χ 22m 2 χm 2 k + ) 17m4 k m 2 χ m 2 v 2 k g Λ = 1 m 2 k /m 2 χ 192πΛ 4

24 Idea and example Requiring σ max l v + σh max v 3 26 cm 3 s GeV 2 assume e.g. m χ 5 GeV, in a model with only electronic coupling and vector-like interaction: (Λ e ) min 480 GeV from LEP m χ >> m h, m l σ V v m2 χ πλ m2 χ e πλ 4 h g h 16 g l = m2 χ πλ 4 e (1 + 3 g2 h gl 2 ) % ann. rate to hadrons

25 Numerical Results from LEP bounds: Vector Scalar Axial t Scalar 0 Vector Scalar Axial t Scalar 0 80 (%) Br h Electronic couplings m (GeV) χ Most-conservative: Universal-leptonic, vector Less-conservative: Electronic, scalar (%) Br h (%) Br h Charged leptonic couplings mχ (GeV) Vector Scalar Axial t Scalar Universal leptonic couplings m (GeV) χ

26 Combined analysis

27 Combined analysis

28 Numerical Results: universal-leptonic, vector gh/ge 0 Vectorial coupling χ γµ χ f γµ f WMAP gh/ge 0 Vectorial coupling χ γµ χ f γµ f WMAP + LEP gh/ge 0 1 Vectorial coupling χ γµ χ f γµ f Mdm (GeV) WMAP + LEP + TEVATRON gh/ge 0 1 Vectorial coupling χ γµ χ f γµ f Mdm (GeV) 1 1 WMAP + LEP + TEVATRON + XENON Mdm (GeV) Mdm (GeV)

29 Numerical Results: electronic, scalar gh/ge 0 gh/ge 0 WMAP + TEVATRON Scalar coupling χ χ f f 1 1 WMAP + LEP Scalar coupling χ χ f f 1 1 Allowed 2 Allowed Mdm (GeV) Mdm (GeV)

30 Scalar Dark Matter L e = g e Λ S χχēe Madgraph analysis: same bckgr: e + e γν ν χ 2 -analysis signal+bckgr sim. Infer bounds for σs,e s v : σs,e s v ( 1 m2 e m 2 χ g 2 e 4πΛ 2 S Result: σ s S,e 24 cm 3 /s ) 3/2 + g 2 e 32πΛ 2 S v 2. No constraints from LEP, nor Tevatron Λ S ge σv 26 5TeV LHC? Events (for 650 pb -1 ) scalar DM; scalar Op. m = GeV; S = 300 GeV signal + bckg data E (GeV)

31 LHC (Fox et al. ph/ )

32 Conclusions Nature of DM coupling is crucial to fit all present data We computed the rate of hadronic/leptonic coupling to respect: 1 LEP + Tevatron (mono-photon, mono-jet events) 2 WMAP + XENON0 A very light fermionic DM ( GeV) mainly excluded whatever the type of interaction Heavier candidates ( GeV) should be largely hadrophobic (vector int.) or even excluded (scalar int.) Models with electrophilic couplings (motivated by INTEGRAL, or Synchrotron radiation data) are excluded by LEP/Tevatron analysis Escaping conclusions: DM candidate not coupled to electrons (LEP bound not applicable) or hadronic coupling only to bottom or charm (Tevatron bound not applicable) Nothing to say for the moment for scalar DM.

33 merci beaucoup!

34 Back-up. Light-mediators

35 Back-up. High-energy completions