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[C II] 158 m Emission from Damped Ly Systems Art Wolfe and Ken Nagamine UCSD UCSD
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DLAS are Definition of Damped Ly System (DLA): N(HI) > 2*10 20 cm -2 Distinguishing characteristic of DLAs : Gas is Neutral
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DLAS are Definition: N(HI) > 2*10 20 cm -2 Distinguishing characteristic of DLAs : Gas is Neutral Stars form out of cold gas
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DLAs Dominate the Neutral Gas Content of the Universe at z=[0,5] Gas Content of DLAs at z=[3,4] Accounts for current visible Mass DLAs Serve as Important Neutral Gas Reservoirs for Star Formation Relevance of DLAs for Star Formation
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DLAs Dominate the Neutral Gas Content of the Universe at z=[0,5] Gas Content of DLAs at z=[3,4] Accounts for current visible Mass DLAs Serve as Important Neutral Gas Reservoirs for Star Formation Mass per unit Comoving Volume versus redshift
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DLAs Dominate the Neutral Gas Content of the Universe at z=[0,5] Gas Content of DLAs at z=[3,4] Accounts for current visible Mass DLAs Serve as Important Neutral Gas Reservoirs for Star Formation Current Visible Matter Neutral Gas at High z
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HIRES Metal-line Velocity Profiles in DLAs High-resolution spectroscopy on very large telescopes can yield quantitative information about DLAs: Cooling Rates Star formation rates. SFRs Thermal Pressure Chemistry Kinematics Nucleosynthesis Dust & Nucleosynthesis Nucleosynthesis
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Obtaining Cooling Rates from CII* Absorption [C II] 158 micron transition dominates cooling of neutral gas in Galaxy ISM Spontaneous emission rate per atom l c =n [CII] obtained from strength of 1335.7 absorption and Lyman alpha absorption Thermal equilibrium condition l c = pe gives heating rate per atom
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[C II] 158 micron Emission rates vs N(H I) Median l c =10 -26.6 ergs s -1 H -1 for positive Detections Upper limits tend to have low N(H I) DLA l c values about 30 times lower than for Galaxy: explained by lower dust content and similar SFRs per unit area
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Effect of Adding Local FUV Heating
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An LBG Galaxy Associated with a DLA (Moller etal ‘02) 8.4 kpc Ly Emission [O III] Emission CII * Absorption
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[C II] contours superposed on 6.75 m Image
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[C II] Flux Densities Predicted for DLAs
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Predicted S 0 for DLA 2206-19A 3 Alma limit for 20 hr integration time3 Alma limit for 20 hr integration time 90 % Mass range predicted for CDM Models of DLAs90 % Mass range predicted for CDM Models of DLAs M H I =m D MM H I =m D M
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Tentative l c versus v relation DLA2206-19ADLA2206-19A CDM Models predict v = 0.6v cCDM Models predict v = 0.6v c M=v c 3 /10GH(z)M=v c 3 /10GH(z)
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DLA2206-19A S 0 impliedfor Mass predicted by l c versus v relationS 0 implied for Mass predicted by l c versus v relation
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17 kpc 608 MHz VLBI Map of PKS 0458-02
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Single-Dish versus VLBI 21 cm Absorption profiles for DLA 0458-02 at z=2.0394 for DLA 0458-02 at z=2.0394
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Alma Sensitivity for Detection of C II Emission Lower Limit for DLA0458-02 forLower Limit for DLA0458-02 for M H I =10 10 M sun M H I =10 10 M sun
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Predicted S 0 for full Sample “Redshift Desert’’“Redshift Desert’’ CNM confirmed by absence of Si II * 1264 absorptionCNM confirmed by absence of Si II * 1264 absorption
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