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Презентация была опубликована 11 лет назад пользователемВладислава Ярыгина
2 Первичный нуклеосинтез и межзвездные молекулярные H 2 /HD облака на больших красных смещениях Д.Варшалович 1, А.Иванчик 1, П.Петижан Первичный нуклеосинтез и межзвездные молекулярные H 2 /HD облака на больших красных смещениях Д.Варшалович 1, А.Иванчик 1, П.Петижан 2 1 ФТИ им. А.Ф. Иоффе РАН, С.-Петербург, Россия 2 Институт астрофизики Парижа, Франция 2008
4 BBN Epoch: Evolution of Nuclear Composition t ~2.6 min (D/H) max ~ 0.7·10 -2 kT BBN ~ 70 keV n B (BBN) ~ cm -3 n (BBN) ~ cm -3
5 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 Contemporary density Fraction of Baryons The Standard Matter Fraction is ~ 5% !!! M H /M B ~0.76 M He4 /M B ~0.24 M Z /M B
6 CMBR: T 0 =2.726 K, (0)=0.26 eV/cm 3, n (0)=411 cm -3 the Redshifted Thermal Radiation of the Primordial Plasma at the Recombination Epoch: t R ~ 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
8 DI/HI Atomic Lines in QSO Absorption Spectra Ly ÅH I ÅD I (H I) / (D I) = [D I] / [H I] (2.0±0.5) Webb et al (2.6±0.4) Kirkman et al Primordial Nucleosynthesis n B /n h 2 Const(t) B 0.044±0.004 (Burles et al. 2001) Difficulties of DI/ HI line identification
14 H 2 absorption lines imprinted in QSO spectrum (z abs = )
16 Н 2 rotational level populations N J=5 = (2.3±0.3) cm -2 N J=4 = (5.0±0.6) cm -2 N J=3 = (2.3±0.5) cm -2 N J=2 = (6.0±3.0) cm -2 N J=1 = (1.9±0.1) cm -2 N J=0 = (2.8±0.1) cm -2 N(H 2 ) = N J = = (4.8±0.2) cm -2
17 HD absorption lines imprinted in QSO spectrum (z abs = )
19 Interstellar Molecular Clouds 12 Gyr ago: [H 2 ] ~ 4.8·10 19 cm -2 [HD] ~ 3.5·10 15 cm -2 Our Epoch: [H 2 ] ~ 3.4·10 20 cm -2 [HD] ~ 2.1·10 14 cm -2
20 Results n Absorption system z a = in Q spectrum n The limit of HD/H 2 chemistry n The primordial D abundance 4 He 2 D 3 He 7 Li CMBR
21 D/H abundances vs BBN theory After Big Bang BBN 2.8 min CMBR yr QSO Abs yr Our Galaxy yr D is destroyed in stars: so D/H decreases during galaxy evolution with cosmological time
22 Conclusions n HD-molecules at high redshift are detected for the first time. n Primeval molecular cloud H 2 -HD existed 12 Gyr ago was discovered. n The ratio of [HD]/[H 2 ] in the primeval cloud is significantly larger than that in the interstellar clouds of our Galaxy. The value n B /n from [HD]/[H 2 ] agrees with that from 4 He, 3 He, 7 Li observations but disagrees with D/H from DI/HI atomic lines. The value n B /n from [HD]/[H 2 ] agrees with that from 4 He, 3 He, 7 Li observations but disagrees with D/H from DI/HI atomic lines. The fraction of baryon matter B from [HD]/[H 2 ] is a bit less but marginally coincides with B from CMBR WMAP. The fraction of baryon matter B from [HD]/[H 2 ] is a bit less but marginally coincides with B from CMBR WMAP.
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