Charged SUSY particles andtheir effects on cosmology
Kazunori Kohri （郡和範）

Physics Department, Lancaster University
Kawasaki, Kohri, Moroi, PLB625 (2005) 7
Kawasaki, Kohri, Moroi, PRD71 (2005) 083502
Kohri, Moroi, Yotsuyanagi, PRD73 (2006) 123511
Kohri and Takayama, hep-ph/0605243
Kanzaki et al, hep-ph/0609246

Gravitino Decay and BBN
1.

Gravitinos are unstable in Gravity Mediation SUSY
Radiative decay

Bγ = 1⎛ m3/2 ⎞τ (ψ 3/ 2 → γ + γ) = 4 × 10 sec ⎜⎟⎝ 100 GeV ⎠8−3Hadronic decay⎛ m3/2 ⎞τ (ψ 3/ 2 → g + g ) = 6 × 10 sec ⎜⎟⎝ 100 GeV ⎠7−3Bh = 1 ( Bγ ≈ O(1))

Non-thermal Li6 Production

Dimopoulos et al (1989)i.

He3 (T) production

Jedamzik (2000)
Kawasaki,Kohri,Moroi (2001)⎧n + HeHe+γ → ⎨p +T⎩
ii. Li6 production
T + 4He → 6Li+n [8.4 MeV]
43He+ 4He → 6Li+p [7.0 MeV]

3T, 3HeHe

4Coulomb energy loss by background electronsdE 4πα 2Z 2 Λne=,dxme β

Λ ~ O (1)Hadronic decay

Reno, Seckel (1988)
S. Dimopoulos et al.(1989)

Two hadron jets with

E jet = mX /3

Bh ≈ α / 4π ≈ 10−3

One hadron jet with

E jet = mX /2

Bh = 1

（I) Early stage of BBN (before/during BBN)

Reno and Seckel (1988) Kohri (2001)

Extraordinary inter-conversion reactions between n and pcf)

n +π + → p +π 0p +π − → n +π 0

weakstrongΓn ↔ p = Γ n ↔ p + Γ n ↔ p

Hadron induced
exchangeΓn ↔ p ↑ ⇒ n / p ↑Even after freeze-out of n/p in SBBN

More He4, D, Li7 …

(II) Late stage of BBN
Hadronic showers and “Hadro-dissociation”

E n= Ef(p)S. Dimopoulos et al. (1988)
Kawasaki, Kohri, Moroi (2004)
Jedamzik (2006)

Non-thermal Li, Be Production byenergetic hadrons
Dimopoulos et al (1989)
3
⎧He+X
4
N + He → ⎨⎩T + X

N + He → He +X
44*T, 3HeHe

4He

4Energy loss

① T(He3) – He4 collision
T + 4He → 6Li + n[8.4 MeV]

He + 4He → 6Li + p[7.0 MeV]

3② He4 – He4 collision
He + 4He → 6Li, 7Li, 7Be + ...

4

Upper bound on reheating temperature
Kawasaki, Kohri, Moroi (2004)

Bh (ψ μ → g + g ) = 1
TR = 109 GeV (Y3/ 2 /10 −12 )m3/ 2 = 500GeV (τ 3/2/4 × 105 sec) −1 / 3

Sneutrino NLSP, Gravitino LSP and
inplication for Thermal Leptogenesis
Kanzaki, Kawasaki, Kohri, Moroi (2006)ν → ν + ψ μThermal-relic sneurinos can not produce sufficient DM Ω3/2Yν ~ 2 × 10−14 ( mν /100GeV )Fujii, Ibe, Yanagida (04)This region might be
excluded in neutralino / stau
NLSP scenarios
Feng, Su, Tankayama (04)
Steffen (06)

Only reheating process can produce sufficient Gravitino DM
Ω3/2h2～ 0.11
Lighter gravitino masslarger gaugino mass (σ∝M12 )Overproduction ofGravitinos for a fixed TR

M 1 (> mν )Different
fromneutralino/ stau
Ω3/2
h2 ～
0.11
NLSP scenario !
Thermal Leptogensis (Fukugita andYanagida (1986), Buchmuller, Bari,Pluacher (05) ) does still work!
Higher TR can be realized atLarger gravitino mass
lighter gaugino massHigh TR

Solving Li7 problem in Hadronic decay

Jedamzik (04); Jedamzik etal (05)severer observations
Ryan etal (‘00), Asplund etal (‘05)η = (2 − 4) × 10 −10 at 2σ?
( 7Li/H)SBBN =(4-5)×10-10(η=ηWMAP =(6.1±0.6)×10-10 )Neuron emission fromhadronic shower

Be + n → 2 4He

7

Li7 can be reduced!
( 7Be + e − → 7Li + γ )More Li6 can be also produced!

α +α → 6Li+D

Kohri, Moroi, Yotsuyanagi (2005)
Kohri et al (2006)

CHArged Massive Particle (CHAMP)
and Cosmology
Cahn and Glashow (1981)Kohri and Takayama, hep-ph/0605243

Many candidates of long-lived CHAMP, e.g., scalar leptons (stauetc) as NLSPs, which eventually decays into DM (gravitino) andstandard particles
More massive elements tend to capture CHAMP earlier
because of larger binding energy of the bound states(Tcapture =Ebin/40 ~ 1-10 keV, Ebin ~α2 Z2champ Z2nuc mnuc)
Note that ligher nuclei have been freezeout after T= Tcapture
CHAMP captured-nuclei change the nuclear reaction rates
through the modifications of the Coulomb suppression factor
and their kinematics.
Only Be7 and Li7 can be reduced without changing D, He3, andHe4 abundances

Binding energy Ebin ~ α2 Z2champ Z2nuc mnuc

Time evolution of light elements

CHAMP (ChArged Massive Particle)
Pospelov (06)and BBN
Kohri and Takayama (06)Kaplinghat and Rajaraman (06)Cyburt, et at (06)Charged particles may recombine with light elements toform bound states such as a hydrogen atom in the early CUniverse for T < Ebin /40 (~ 1-10 keV)At least
zCharge suppression

Nucleus+zKinetic energy modification into the order of binding energy
Ebin = α2mnuc~O(0.1) – O(1) MeV (note that E~T in SBBN )Pospelov’s Effect? - possible enhancement of cross sections in quadrupole Interesting!, but still some unclear points(lack of cross section data of He4(d,γ)Li6 at E < 0.1 MeV, etc…)

CHAMP BBN (CBBN) may solve Lithium
Kohri and Takayama, hep-ph/0605243
problem? I
Short lifetime ( < 106 sec)
• Only Be7 and Li7 captures CHAMP• Be7 (n,a)He4 and Li7(p,a)He4
are enhanced
However, the experimental data of
the cross section for Be7 (n,a)He4
is not sufficent at E = O(Ebin)
Here 10 times larger uncertainty inp-wave mode is assumed (seeSerpico et al (04) [B-II case]We need correct experimental data at E = Ebin

CHAMP BBN (CBBN) may solve Lithiumproblem? IIKohri and Takayama, hep-ph/0605243
Long lifetime ( > 106 sec)
Znuc =1 nuclei (proton, D, and T) are captured
He4(d, g)Li6 and Be7(d, p a)He4
are enhancecd
However, CHAMP maychange its partner from p,D,T into more massive ones
before nuclear reactions
occur because

aBohr > rnuc

Should we solve the three body problem?

Discussion and Conclusion• The radiative and hadronic decay products destroy He4, bywhich D,He3, Li6 are overproduced.
• The constraint on reheating temperature after primordial
inflation becomes very stringent in Hadronic decay scenario of
unstable gravitino.

TR ≤ 3 × 105 GeV − 107 GeV(for m3/ 2 = 100 GeV − a few TeV)
• Hadronic-decay scenario may solve the Li problem• Gravitino LSP, Sneutrino NLSP scenario agree with Thermal
Leptogeneis• CHAMP BBN is attractive (Kohri and Takayama ‘06, Cyburt etal‘06) or might be dangerous? (Pospelov ‘06).