Seminário no Valongo

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.