CAAUL Seminar - Herschel-ATLAS and ALMA: An Einstein Ring of Molecular Gas and Dust in the z=1 source G15.v2.19 - 4 janeiro 2013

Herschel-ATLAS and ALMA: An Einstein Ring of Molecular Gas and Dust in the z=1 source G15.v2.19 

Hugo Messias

Universidad de Concepción, Chile

Resumo

Among the several contributions of the Herschel-ATLAS survey, one which stands out is the reliable selection of gravitational lens systems by means of a simple far-infrared flux cut (Negrello et al. 2010). This talk is about one of the brightest source in the sample (with S500 μm = 194 mJy), which has been observed with ALMA. Two scheduling blocks (SBs) have been delivered so far. These comprise Bands 3 (with 25 antennas) and 6 (17) setups, observed in extended configuration (maximum baseline ~450 m). The continuum emission (at 101 and 226 GHz) was successfully detected, as well as line emission from the following transitions: 12CO J:2→1 and J:4→3; CI 3P1 →3P0; and CS J:10→9. Ancillary data (HST, Keck-AO) shows a typical quad lensed system close to a fold caustic, with a nearly complete Einstein ring. However, obscuration induced by the foreground lens disc galaxy has so far prevented an acceptable lens model. Nevertheless, the CO line has a FWHM narrower than those observed in SMGs and shows a double peaked profile. This, together with an impressive CS J:10-9 detection, its observed FIR flux, and the preliminary reconstructed source velocity map, hints for a highly dense merger environment and regions of high magnification (up to factors of ~14).

4 de janeiro de 2013 | 14:30

Local

OAL - Seminar Room
Tapada da Ajuda - Edifício Leste - 2º Piso
1349-018 Lisboa