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宇宙初期の元素合成とダークマター. 郡 和範 Kazunori Kohri. 英 ランカスター大 → 東北大・理・物理. 内容. ビッグバン元素合成 (BBN) のレヴュー 超対称性 (SUSY) と超重力理論 (SUGRA) のレヴュー ダークマター候補となる Lightest SUSY Particle (LSP) BBN から得られる LSP と Next LSP (NLSP) の情報 結論. Brief review of Big-bang nucleosynthesis (BBN). 宇宙温度と宇宙年齢.
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宇宙初期の元素合成とダークマター 郡 和範 Kazunori Kohri 英ランカスター大 → 東北大・理・物理
内容 • ビッグバン元素合成 (BBN)のレヴュー • 超対称性(SUSY) と超重力理論(SUGRA)のレヴュー • ダークマター候補となるLightest SUSY Particle (LSP) • BBN から得られる LSP と Next LSP (NLSP)の情報 • 結論
宇宙温度と宇宙年齢 • フリードマン方程式 (一般相対論的一様等方平坦宇宙モデル)
Thermal history of the Universe cf) 1 GeV ~ 1013K Big bang Planck scale GUT phase transition? Electroweak phase transition QCD phase transition Neutrino decoupling Electron-positron annihilation Matter-radiation equality Photon decoupling (CMB) Inflation and Reheating Baryogenesis? Big-Bang Nucleosynthesis (BBN) Present
Thermal history around BBN Epoch cf) 100 MeV ~ 1012K Muon annihilation Neutrino decoupling n/p freezeout Electron-positron annihilation Beginning of BBN End of (Standard) BBN
Scenario of BBN cf) 1 MeV ~ 1010K Radiation Matter Weak interaction is in equilibrium
cf) 1 MeV ~ 1010K Feezeout of weak interaction • Weak interaction rate • Hubble expansion rate
He4 mass fraction n p p n
cf) 0.1 MeV ~ 109K There is no stable nuclei for A=5,8. Mass 7 nuclei are produced a little.
Observational light element abundances • Observe the recombination line in Metal poor extragalactic H II region, or blue compact galaxy • Identifying H II region as He II region • Extrapolating them into zero metalicity Fukugita, Kawasaki (06) Peimbert, Luridiana, Peimbert (07) Izotov, Thuan, Stasinska (07) Fukugita, Kawasaki (06)
D H 82km/sec 2) Deuterium Observed in high redshift QSO absorption system QSO Lyα(z~3) O’Meara et al.(2006) Burles and Tytler (1997)
2) Lithium 7 • Observing metal poor halo stars in Pop II • Abundance does not depend on metalicity so much for “Spite’s plateau” Bonifacio et al (2006) Lemoine et al., 1997
Observational Light Element Abundances Fukugita, Kawasaki (2006) • He4 • D • Li7 • Li6 • He3 Peimbert,Lridiana, Peimbert(2007) Izotov,Thuan, Stasinska (2007) O’Meara et al. (2006) Melendez,Ramirez(2004) Asplund et al(2006) Geiss and Gloeckler (2003)
Dark Matter? Einstein’s Cosmological Constant Or unknown scalar field? Dark side? Dark Side 96% Dark side? Unknown SUSY particles? Light side (Baryon) 4% http://map.gsfc.nasa.gov/media/060916
Realistic candidates of particle dark matter in SUSY/SUGRA • Neutralino χ(Bino, wino, or higgsinos) Most famous Lightest Supersymmetric Particle (LSP) with mχ~100GeV (appears even in global SUSY) • Gravitinoψμ super partner of graviton with spin 3/2 and m3/2100GeV (massive only in SUGRA (local SUSY))
Introduction toSUSY • Supersymmetry (SUSY) • Solving “Hierarchy Problem” • Realizing “Coupling constant unification in GUT” FermionBoson quarksquark leptonslepton photinophoton neutralino gravitinograviton axinoaxion Depending on SUGRA models
Hierarchy Problems • GUT-scale • Weak-scale 12-13 orders of magnitude !!! Higgs mass where Higgs’s potential c.f) Masses of fermions and vector bosons
Radiative correction to Higgs mass in Quantum Field Theory Quadratic divergence
GDP in USA (2002)? $ 10,110,087,734,958.95 -) $ 10,110,087,734,957.70 $ 1.25 Weak scale in the tree level, In total, How can we resolve the problem? To retain the hierarchy, we require an accidental cancellation, Fine tuning!
h t In exact SUSY, the quadratic divergence is canceled by both boson and fermion loops. Solution in SUSY Exact SUSY Even if SUSY, We don’t need a fine tuning when
The coupling constants are unified at SUSY GUT A lot of new particles ,which do not obey the asymptotic free, appear at Martin, ”A Supersymmetry Primer”
MSSM • Minimal extension of Standard Model to supersymmetry including two Higgs doublets • 105 masses, phases and mixing angles!!!
CMSSM Constrained MSSM Simplified into only five parameters from 105 • Common scalar mass at GUT scale:m0 • Unified gaugino (fermion) mass at GUT scale: m1/2 • Ratio of Higgs vacuum expectation values: • Higgs/higgsino mass parameter (or its signature): μ • tri-linear coupling A0
Super particles in CMSSM stop sneutrino stau bino, wino, higgsinos Martin, ”A Supersymmetry Primer”
Running of Renormalization Group (RG) Equation in CMSSM Negative Higgs mass term Martin, ”A Supersymmetry Primer”
Mass spectrum in CMSSM stop sneutrino stau neutralino Martin, ”A Supersymmetry Primer”
Lightest SUSY particle (LSP) • R-parity conservation i)Decay ii) Pair annihilation/production (-1) (-1)× (+1) (+1) × (+1) (-1)× (-1)
Thermal freezeout Boltzmann equation ∝Exp[-m/T] Kolb & Turner Ωχ does not depend on mχ Predicting TeV Physics!!!
LSP (LOSP) in CMSSM Neutralino or Scalar tau lepton (Stau) is the Lightest Ordinary SUSY Particle (LOSP) ΩLOSP= Ωobs χ LOSP χ LOSP ΩLOSP= Ωobs Ellis,Olive,Santoso,Spanos(03)
Supergravitiy (SUGRA) • Local theory of SUSY (predicting gravitino) • Models of supersymmetry breaking (gravitino mass production by eating goldstino which appears in spontaneous symmetry breaking) • Including general relativity (Unifying space-time symmetry with local SUSY transformation)
SUSY Breaking Models • Gravity mediated SUSY breaking model Hidden sector Observable sector quark, squark, … Only through gravity • Masses of squarks and sleptons • Gravitino mass
SUSY Breaking Models II • Gauge-mediated SUSY breaking model SUSY breaking sector Observable sector quark, squark, … Gauge interaction Gauge interaction Messenger sector Lightest SUSY particle (LSP) may be necessarily the gravitino
How heavy is the gravitino? • NLSP gravitino • LSP gravitino decaying into LSP NLSP decays into gravitino Lifetime Lifetime
Massive particle decaying during/after BBN epoch produceshigh energy photons,hadrons, and neutrinos Destruction/production/dilution of light elements Severer constraints on the number density Sato and Kobayashi (1977), Lindley (1984,1985), Khlopov and Linde (1984) Ellis, Kim, Nanopoulos, (1984); Ellis, Nanopoulos, Sarkar (1985) Kawasaki and Sato (1987) Reno and Seckel (1988), Dimopoulos, Esmailzadeh, Hall, Starkman (1988) Kawasaki, Moroi (1994), Sigl et al (95), Holtmann et al (97) Jedamzik (2000), Kawasaki, Kohri, Moroi (2001), Kohri(2001), Cyburt, Ellis, Fields, Olive (2003) Kawasaki, Kohri, Moroi(04), Jedamzik (06)
Radiative decay mode D + p + n He3/D >~ O(1)
Hadronic decay mode Reno, Seckel (1988) S. Dimopoulos et al.(1989)
Photon spectrum by radiatively decaying particles Kawasaki, Moroi (1994)
Non-thermal Li6 Production Dimopoulos et al (1989) Jedamzik (2000) Kawasaki,Kohri,Moroi (2001) • He3 (T) production • Li6 production Coulomb energy loss by background electrons
mu- and y- distortion of CMB Photodissociation Kawasaki, Kohri, Moroi (2001)
Hadronic decay Reno, Seckel (1988) Dimopoulos et al.(1989)
Hadron-fragmentation Monte Carlo event generator, JETSET 7.4 (PYTHIA 5.7) Sjostrand (1994) Kohri (2001)
Contours of final energy of energetic proton Contours of final energy of energetic neutron