M. J. Barlow, do University College London, ministrará palestra em inglês no dia seis de junho, 16h, no Observatório do Valongo, localizado na Ladeira do Pedro Antônio, 43, Centro, sob o título “Mid-IR Spitzer and Gemini studies of dust production by young core-collapse supernovae”.
A seguir, o resumo da exposição:
Using primarily the Gemini and Spitzer telescopes, we have been conducting a Survey for the Evolution of Emission from Dust in Supernovae (SEEDS), in order to assess the observational case for dust formation by core-collapse SNe and whether they provide an important contribution to the dust budget of galaxies, as suggested by nucleation theory and by the existence of extremely dusty, IR-luminous galaxies at high redshifts.
Spitzer and Gemini detections of SN 2002hh in NGC 6946 were consistent with emission from nearby pre-existing dust, possibly from a previously ejected circumstellar shell. Subsequent observations confirm that its IR emission did not fade as expected for newly-formed, ejecta-condensed dust. Our HST imaging shows that this SN’s optical emission is in fact coming from a just-resolved light echo, providing a likely explanation for its extended IIP (plateau) light curve. Recently we reported only the second unambiguous detection of dust formation in the ejecta of a Type II SN, from SN 2003gd in M 74. Using clumped-dust Monte Carlo radiative transfer modelling, we estimated a dust mass of up to 0.02 solar masses by day 678, implying that dust formation in core-collapse SNe can be efficient. Further results from our continued monitoring of these and other massive-star SNe, including SN 1999bw, SN 2004dj and SN 2004et, will be presented.
Para maiores informações, o telefone do Valongo é 2263-0685.