High angular resolution ALMA images of dust and molecules in the SN 1987A ejecta
We present high angular resolution (~80 mas) ALMA continuum images of the SN 1987A system, together with CO J = 2 $\to $ 1, J = 6 $\to $ 5, and SiO J = 5 $\to $ 4 to J = 7 $\to $ 6 images, which clearly resolve the ejecta (dust continuum and molecules) and ring (synchrotron continuum) components. Du...
Autors principals: | , , , , |
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Format: | Journal article |
Idioma: | English |
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American Astronomical Society
2019
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author | Cigan, P Matsuura, M Gomez, HL Indebetouw, R Roche, P |
author_facet | Cigan, P Matsuura, M Gomez, HL Indebetouw, R Roche, P |
author_sort | Cigan, P |
collection | OXFORD |
description | We present high angular resolution (~80 mas) ALMA continuum images of the SN 1987A system, together with CO J = 2 $\to $ 1, J = 6 $\to $ 5, and SiO J = 5 $\to $ 4 to J = 7 $\to $ 6 images, which clearly resolve the ejecta (dust continuum and molecules) and ring (synchrotron continuum) components. Dust in the ejecta is asymmetric and clumpy, and overall the dust fills the spatial void seen in Hα images, filling that region with material from heavier elements. The dust clumps generally fill the space where CO J = 6 $\to $ 5 is fainter, tentatively indicating that these dust clumps and CO are locationally and chemically linked. In these regions, carbonaceous dust grains might have formed after dissociation of CO. The dust grains would have cooled by radiation, and subsequent collisions of grains with gas would also cool the gas, suppressing the CO J = 6 $\to $ 5 intensity. The data show a dust peak spatially coincident with the molecular hole seen in previous ALMA CO J = 2 $\to $ 1 and SiO J = 5 $\to $ 4 images. That dust peak, combined with CO and SiO line spectra, suggests that the dust and gas could be at higher temperatures than the surrounding material, though higher density cannot be totally excluded. One of the possibilities is that a compact source provides additional heat at that location. Fits to the far-infrared–millimeter spectral energy distribution give ejecta dust temperatures of 18–23 K. We revise the ejecta dust mass to M dust = 0.2–0.4 ${M}_{\odot }$ for carbon or silicate grains, or a maximum of <0.7 ${M}_{\odot }$ for a mixture of grain species, using the predicted nucleosynthesis yields as an upper limit. |
first_indexed | 2024-03-06T18:23:04Z |
format | Journal article |
id | oxford-uuid:06f962ed-2b7d-47fe-a07d-18a2c257b70f |
institution | University of Oxford |
language | English |
last_indexed | 2024-03-06T18:23:04Z |
publishDate | 2019 |
publisher | American Astronomical Society |
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spelling | oxford-uuid:06f962ed-2b7d-47fe-a07d-18a2c257b70f2022-03-26T09:05:13ZHigh angular resolution ALMA images of dust and molecules in the SN 1987A ejectaJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:06f962ed-2b7d-47fe-a07d-18a2c257b70fEnglishSymplectic Elements at OxfordAmerican Astronomical Society2019Cigan, PMatsuura, MGomez, HLIndebetouw, RRoche, PWe present high angular resolution (~80 mas) ALMA continuum images of the SN 1987A system, together with CO J = 2 $\to $ 1, J = 6 $\to $ 5, and SiO J = 5 $\to $ 4 to J = 7 $\to $ 6 images, which clearly resolve the ejecta (dust continuum and molecules) and ring (synchrotron continuum) components. Dust in the ejecta is asymmetric and clumpy, and overall the dust fills the spatial void seen in Hα images, filling that region with material from heavier elements. The dust clumps generally fill the space where CO J = 6 $\to $ 5 is fainter, tentatively indicating that these dust clumps and CO are locationally and chemically linked. In these regions, carbonaceous dust grains might have formed after dissociation of CO. The dust grains would have cooled by radiation, and subsequent collisions of grains with gas would also cool the gas, suppressing the CO J = 6 $\to $ 5 intensity. The data show a dust peak spatially coincident with the molecular hole seen in previous ALMA CO J = 2 $\to $ 1 and SiO J = 5 $\to $ 4 images. That dust peak, combined with CO and SiO line spectra, suggests that the dust and gas could be at higher temperatures than the surrounding material, though higher density cannot be totally excluded. One of the possibilities is that a compact source provides additional heat at that location. Fits to the far-infrared–millimeter spectral energy distribution give ejecta dust temperatures of 18–23 K. We revise the ejecta dust mass to M dust = 0.2–0.4 ${M}_{\odot }$ for carbon or silicate grains, or a maximum of <0.7 ${M}_{\odot }$ for a mixture of grain species, using the predicted nucleosynthesis yields as an upper limit. |
spellingShingle | Cigan, P Matsuura, M Gomez, HL Indebetouw, R Roche, P High angular resolution ALMA images of dust and molecules in the SN 1987A ejecta |
title | High angular resolution ALMA images of dust and molecules in the SN 1987A ejecta |
title_full | High angular resolution ALMA images of dust and molecules in the SN 1987A ejecta |
title_fullStr | High angular resolution ALMA images of dust and molecules in the SN 1987A ejecta |
title_full_unstemmed | High angular resolution ALMA images of dust and molecules in the SN 1987A ejecta |
title_short | High angular resolution ALMA images of dust and molecules in the SN 1987A ejecta |
title_sort | high angular resolution alma images of dust and molecules in the sn 1987a ejecta |
work_keys_str_mv | AT ciganp highangularresolutionalmaimagesofdustandmoleculesinthesn1987aejecta AT matsuuram highangularresolutionalmaimagesofdustandmoleculesinthesn1987aejecta AT gomezhl highangularresolutionalmaimagesofdustandmoleculesinthesn1987aejecta AT indebetouwr highangularresolutionalmaimagesofdustandmoleculesinthesn1987aejecta AT rochep highangularresolutionalmaimagesofdustandmoleculesinthesn1987aejecta |