1990 Fiscal Year Annual Research Report

宇宙のQCD相転移とビッグバンにおける元素合成の理論的研究

Research Project

Project/Area Number	01540253
Research Institution	Tokyo Metropolitan University
Principal Investigator	梶野敏貴東京都立大学, 理学部, 助手 (20169444)
Co-Investigator(Kenkyū-buntansha)	土岐博東京都立大学, 理学部, 助教授 (70163962) 久保謙一東京都立大学, 理学部, 教授 (50013389)
Keywords	ビッグバン / QCD(量子色力学) / 相転移 / 始源的元素合成 / フラックス・チュ-ブ・モデル / クォ-ク・グルオン・プラズマ / 非一様モデル / ストレンジ・クォ-ク物質
Research Abstract	カラ-・フラックス・チュ-ブ・モデルを用いて相境界でのバリオン透過率を計算した。この結果を,宇宙のQCD相転移の次数が一次との仮定でビッグバン宇宙初期に適用し,相転移終了までにクォ-ク・グルオン相中のバリオン数密度がどこまで高密度になるかを計算した。その結果,150<TcMeVならばバリオン数密度分布はほぼ一様に近く,Tc<150MeV,且つ,10^5<σ<10^7MeV^3ならば密度分布は大きく揺らぎ,揺らぎの間隔が10〜100mであることがわかった。更に,100<Tc<250MeVで,且つ,σ<5×10^5MeV^3ならば高密度領域が核物質密度以上に達して,ストレンジ・クォ-ク物質が形成される可能性があることを明らかにした。 Tc<150MeV,且つ,10^5<σ<10^7MeV^3の場合,元素合成過程が一様密度分布を仮定する標準ビッグバンモデルによるものから大きく異なる。その結果,始源的元素合成理論から導かれる結論が変更される可能性がある。第一は,インフレ-ション宇宙モデルが結論する閉じた宇宙をバリオン質量だけで実現できる可能性,第2は,始源的ストレンジ・クォ-ク物質,ブラックホ-ル,黒色矮星などバリオン起源の暗黒物質で消えた質量問題を解決できる可能性である。有効QCD理論から得られたバリオン数密度分布の揺らぎを初期条件として、非一様モデルによる元素合成の理論計算をやり直した結果,流体力学的不安定性に基づく一様化を取り入れた範囲では,第一の可能性を否定できないことが示された。又,始源的ストレンジ・クォ-ク物質が宇宙初期で核子へ蒸発しきらず,生き残る条件を数値的に求めた。1つのクォ-ク物質が持つバリオン数が10^<39>以上であれば,生き残る。

Research Products
(18 results)

All Other

All Publications (18 results)

[Publications] R.N.Boyd and T.Kajino: "Can ^9Be provide a test of cosmological theories?" Astrophysical Journal. 336. L55-L58 (1989)
[Publications] T.Kajino,G.J.Mathews and K.Ikeda: "Branching ratios for ^3He(^4He,g)^7Be and ^3H(^4He,g)^7Li." Physical Review. C40. 525-530 (1989)
[Publications] T.Kajino,G.F.Bertsch and F.C.Barker: "Energy dependence of astrophysical Sーfactor for radiative charged particle reactions." Journal of Physical Society of Japan. Suppl 58. 639-645 (1989)
[Publications] S.Kubono,H.Orihara,S.Kato and T.Kajino: "Experimental determination of the ^<19>Ne(p,g)^<20>Na reaction rate and breakout problem from hotーCNO cycle." Astrophysical Journal. 344. 460-463 (1989)
[Publications] M.Mizoguchi,K.Sumiyoshi,T.Kajino and H.Toki: "Pionーnucleus scattering in the GeV region." Progress of Theoretical Physics. 81. 1217-1224 (1989)
[Publications] K.Sumiyoshi,K.Kusaka,T.Kamio and T.Kajino: "Baryon evaporation from cosmic quarkーgluon plasma." Physics letters. 225B. 10-14 (1989)
[Publications] T.Kajino: "Primordial nucleosynthesis and radioactive beams." Nuclear Instruments and Methods. (1991)
[Publications] F.C.Barker and T.Kajino: "Channel contributions to low energy ^<12>C(^4He,g)^<16>0 cross sections." Australian Journal of Physics. (1991)
[Publications] S.Kubono et al.: "Structure of ^<21>Mg and the first experimental determination of the ^<20>Na(p,g)^<21>Mg." Nuclear Physics. (1991)
[Publications] Y.Yamamoto,T.Kajino and K.ーI.Kubo: "Theoretical studies of the ^7Li(^3H,n)^9Be reaction and primordial nucleosynthesis of ^9Be."
[Publications] S.Kubono et al.: "New reaction rate for ^8Li(^4He,n)^<11>B and primordial nucleosynthesis of intermediateーtoーheavy mass elements in baryon inhomogeneous cosmologies."
[Publications] T.Kajino,K.Sumiyoshi,C.Alcock and G.Mathews: "A new survival condition of primordial strange quark matter."
[Publications] S.Kubono et al.: "The proton threshold states in ^<21>Mg relevant to the rpーprocess." Zeitschrift fur Physik. A334. 511-512 (1990)
[Publications] T.Kajino and R.N.Boyd: "Production of light elements in primordial nucleosynthesis." Astrophysical Journal. 359. 267-276 (1990)
[Publications] T.Kajino,G.J.Mathews and G.M.Fuller: "Primordial nucleosynthesis of intermediateーmass elements in baryonnumber inhomogeneous bigーbang models:Observational tests." Astrophysical Journal. 364. 7-14 (1990)
[Publications] K.Sumiyoshi,T.Kajino,C.Alcock and G.Mathews: "The evolution of baryon number density during the cosmic quarkhadron phase transition." Physical Review. D42. 3963-3968 (1990)
[Publications] M.Fukugita and T.Kajino: "Contribution of the ^3He(^3He,g)^6Li reaction of primordial ^6Li production." Physical Review. D42. 4251-4253 (1990)
[Publications] T.Kajino: "Can quarkーgluon plasma formation in relativistic heavyーion collisions constrain inhomogeneous cosmologies?" Physical Review Letters. 66. 125-128 (1991)

1990 Fiscal Year Annual Research Report

宇宙のQCD相転移とビッグバンにおける元素合成の理論的研究

Principal Investigator

梶野 敏貴 東京都立大学, 理学部, 助手 (20169444)

Research Products

[Publications] R.N.Boyd and T.Kajino: "Can ^9Be provide a test of cosmological theories?" Astrophysical Journal. 336. L55-L58 (1989)

[Publications] T.Kajino,G.J.Mathews and K.Ikeda: "Branching ratios for ^3He(^4He,g)^7Be and ^3H(^4He,g)^7Li." Physical Review. C40. 525-530 (1989)

[Publications] T.Kajino,G.F.Bertsch and F.C.Barker: "Energy dependence of astrophysical Sーfactor for radiative charged particle reactions." Journal of Physical Society of Japan. Suppl 58. 639-645 (1989)

[Publications] S.Kubono,H.Orihara,S.Kato and T.Kajino: "Experimental determination of the ^<19>Ne(p,g)^<20>Na reaction rate and breakout problem from hotーCNO cycle." Astrophysical Journal. 344. 460-463 (1989)

[Publications] M.Mizoguchi,K.Sumiyoshi,T.Kajino and H.Toki: "Pionーnucleus scattering in the GeV region." Progress of Theoretical Physics. 81. 1217-1224 (1989)

[Publications] K.Sumiyoshi,K.Kusaka,T.Kamio and T.Kajino: "Baryon evaporation from cosmic quarkーgluon plasma." Physics letters. 225B. 10-14 (1989)

[Publications] T.Kajino: "Primordial nucleosynthesis and radioactive beams." Nuclear Instruments and Methods. (1991)

[Publications] F.C.Barker and T.Kajino: "Channel contributions to low energy ^<12>C(^4He,g)^<16>0 cross sections." Australian Journal of Physics. (1991)

[Publications] S.Kubono et al.: "Structure of ^<21>Mg and the first experimental determination of the ^<20>Na(p,g)^<21>Mg." Nuclear Physics. (1991)

[Publications] Y.Yamamoto,T.Kajino and K.ーI.Kubo: "Theoretical studies of the ^7Li(^3H,n)^9Be reaction and primordial nucleosynthesis of ^9Be."

[Publications] S.Kubono et al.: "New reaction rate for ^8Li(^4He,n)^<11>B and primordial nucleosynthesis of intermediateーtoーheavy mass elements in baryon inhomogeneous cosmologies."

[Publications] T.Kajino,K.Sumiyoshi,C.Alcock and G.Mathews: "A new survival condition of primordial strange quark matter."

[Publications] S.Kubono et al.: "The proton threshold states in ^<21>Mg relevant to the rpーprocess." Zeitschrift fur Physik. A334. 511-512 (1990)

[Publications] T.Kajino and R.N.Boyd: "Production of light elements in primordial nucleosynthesis." Astrophysical Journal. 359. 267-276 (1990)

[Publications] T.Kajino,G.J.Mathews and G.M.Fuller: "Primordial nucleosynthesis of intermediateーmass elements in baryonnumber inhomogeneous bigーbang models:Observational tests." Astrophysical Journal. 364. 7-14 (1990)

[Publications] K.Sumiyoshi,T.Kajino,C.Alcock and G.Mathews: "The evolution of baryon number density during the cosmic quarkhadron phase transition." Physical Review. D42. 3963-3968 (1990)

[Publications] M.Fukugita and T.Kajino: "Contribution of the ^3He(^3He,g)^6Li reaction of primordial ^6Li production." Physical Review. D42. 4251-4253 (1990)

[Publications] T.Kajino: "Can quarkーgluon plasma formation in relativistic heavyーion collisions constrain inhomogeneous cosmologies?" Physical Review Letters. 66. 125-128 (1991)

梶野敏貴東京都立大学, 理学部, 助手 (20169444)