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Первичный нуклеосинтез, образование D и содержание HD/H 2 в межзвездных облаках, существовавших 12 млрд. лет назад Д.А. Варшалович, А.В. Иванчик, С.А. Балашев Физико-технический институт им. А.Ф. Иоффе РАН 2009
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BBN Epoch: Evolution of Nuclear Composition t ~ 3-5 min (D/H) max ~ 0.7·10 -2 kT BBN ~ 70 keV n B (BBN) ~ 10 18 -10 19 cm -3 n (BBN) ~ 10 28 cm -3
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Physical Parameters Our Epoch BBN Epoch t ~ 14 Gyrt ~ 3-5 m T 0 = 2.726 K (1+z 0 ) = 1 T B = 0.8 10 9 K (1+z B ) = 3.0 10 8 n = 411 cm -3 = 0.26 eV cm -3 n = 10 28 cm -3 = 2 10 33 eV cm -3 n B = 4.11 10 -8 10 cm -3 B = 39 10 eV cm -3 n B = 10 18 10 cm -3 B = 10 27 10 eV cm -3 10 10 10 (n B /n ) = 6.0 0.5 (CMBR)
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BBN Yield: Light Nuclei Abundances Standard Model n B ( BBN ) is the only free parameter [D] is the most sensitive to n B (BBN) Under Adiabatic Expansion Fraction of Baryon Matter The Standard Matter Fraction is ~ 5% !!! M H /M B ~0.76 M He4 /M B ~0.24 M Z /M B <10 -4 Contemporary density
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CMBR: T 0 =2.726 K, (0)=0.26 eV/cm 3, n (0)=411 cm -3 Redshifted Thermal Radiation of the Primordial Plasma at the Recombination Epoch: t R ~ 400000 yr, T R ~ 3000 K, n B (R) ~ 300 cm -3, n (R) ~5·10 11 cm -3 Anisotropy of CMBR CMBR fluctuations T 0 /T 0 ~10 -5 display a beginning stage of LSS formation. Correlation of the fluctuations Comparison of the theory with observations by WMAP gives: Power spectrum of CMBR fluctuations
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Angular size dependencies on the Space Curvature
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DI/HI Atomic Lines in QSO Absorption Spectra Ly 1215.67 ÅH I 1215.34 ÅD I (H I) / (D I) = 1.00027 [D I] / [H I] (2.0±0.5) Webb et al. 2000 (2.6±0.4) Kirkman et al. 2003 Primordial Nucleosynthesis n B /n h 2 Const(t) B 0.044±0.004 (Burles et al. 2001) Difficulties of DI/ HI line identification
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European South Observatory : Very Large Telescope
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H 2 absorption lines imprinted in QSO 1232+082 spectrum (z abs = 2.33771) Varshalovich, Ivanchik, Petitjean et al., Astron Letters 27, 683, 2001
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HD absorption lines imprinted in QSO 1232+082 spectrum (z abs = 2.33771)
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Interstellar Molecular Clouds 12 Gyr ago: [H 2 ] ~ 4.8·10 19 cm -2 [HD] ~ 3.4·10 15 cm -2 Our Epoch: [H 2 ] ~ 3.4·10 20 cm -2 [HD] ~ 2.1·10 14 cm -2
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Molecular cloud at z=2.33771 n Molecular column densities n HD/H 2 molecular abundance ratio n The limit of HD/H 2 chemistry: D/H isotope ratio
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D/H relative abundances: QSO observational data
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BBN Theory n Baryon/Photon number density ratio corresponding to the D/H isotope ratio n Under Adiabatic Expansion n So, the number density of baryons (average) at our epoch The average fraction of baryon matter at our epoch is
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Observed and predicted BBN abundances 4 He 2 D 3 He 7 Li CMBR After Big Bang BBN 3-5 min CMBR 3.8 10 5 yr QSO Abs. 8.5 10 8 yr Our Galaxy 1.4 10 10 yr D is destroyed in stars: D/H decreases during galaxy evolution with cosmological time
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Conclusions I n n HD-molecules at high redshift are detected for the first time. n n Primeval H 2 -HD molecular cloud was discovered that had existed 12 Gyr ago. n n The ratio of [HD]/[H 2 ] in the primeval cloud was significantly larger than that is observed in the interstellar clouds of our Galaxy.
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n We obtain D/H isotope ratio by independent method from HD/H 2 abundances and include it into the BBN code. The result is n The fraction of baryon matter at our epoch is which coincides (within the errors) with B from CMBR WMAP Conclusions II
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Conclusions III n n Nevertheless, our most probable D/H value is a bit larger than the one commonly accepted today. n n This value is in better agreement with other observational data, including 4 He, 3 He, 7 Li.
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Н 2 rotational level populations N J=5 = (2.3±0.3) 10 14 cm -2 N J=4 = (5.0±0.6) 10 14 cm -2 N J=3 = (2.3±0.5) 10 16 cm -2 N J=2 = (6.0±3.0) 10 16 cm -2 N J=1 = (1.9±0.1) 10 19 cm -2 N J=0 = (2.8±0.1) 10 19 cm -2 N(H 2 ) = N J = = (4.8±0.2) 10 19 cm -2
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Radiative transfer of H 2 lines
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Changing populations of levels with optical depth Balashev, Varshalovich, Ivanchik, Astron Letters 35, 150, 2009
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Nonstandard curves of growth Balashev, Varshalovich, Ivanchik, Astron Letters 35, 150, 2009
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