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Observing project: Molecules in absorption at z ~ 1. Source PKS1830-21. PKS1830-211 z=0.88582. Frye et al 97. 2 images, + Einstein ring But 2 absorbing systems, one at z=0.19 seen in HI. Two components, covering each one image of the source as confirmed by PdB (Wiklind & Combes 1998)
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Observing project: Molecules in absorption at z ~ 1 Source PKS1830-21
PKS1830-211 z=0.88582 Frye et al 97 2 images, + Einstein ring But 2 absorbing systems, one at z=0.19 seen in HI
Two components, covering each one image of the source as confirmed by PdB (Wiklind & Combes 1998) Slight temporal variability
Measuring the continuum of A and B Possible without resolving the source and separating the 2images, since the absorption in A is optically thick A A +B
Monitoring, measure of H0 The single dish (without resolving the 2 images) can follow the intensity of the two, since they are absorbing at two V Monitoring during 3 years (1h per week) ==> delay of 24+5 days, H0 = 69 +12 km/s/Mpc
Measure of Tmb (z) Low excitation (diffuse gas) Tex ~Tmb The case for PKS1830-211 Several transitions give the same result (slightly lower, due to a microlens) From UV H2 lines Srianand et al 2000
Variation of constants Kaluza-Klein theories, Strings and M-theory, predict variations of α = e2/hc fine structure constant Heterodyne resolution R=106 Method of Alkali doublet of many multiplet Webb et al (2001) Appears to have a variation, at high z only Murphy et al (2001) Δ α / α =(-0.72 +0.18 )10-5