Skip to main content Accessibility help
×
Hostname: page-component-848d4c4894-xfwgj Total loading time: 0 Render date: 2024-07-07T00:45:58.898Z Has data issue: false hasContentIssue false

SN 1987A: Observations at Later Phases

from SN 1987A, SN 1993J, and Other Supernovae

Published online by Cambridge University Press:  04 August 2010

P. Bouchet
Affiliation:
European Southern Observatory, La Silla (Chile)
I. J. Danziger
Affiliation:
European Southern Observatory, Garching (Germany)
C. Gouiffes
Affiliation:
DAPNIA/Sap, C. E. Saclay (France)
M. Della Valle
Affiliation:
European Southern Observatory, La Silla (Chile)
A. Monetti
Affiliation:
European Southern Observatory, La Silla (Chile)
Richard McCray
Affiliation:
University of Colorado, Boulder
ZhenRu Wang
Affiliation:
Nanjing University, China
Get access

Summary

The last observations (until April 1993) of SN 1987A made at ESO, La Silla, are presented. Our data show that: (i) the criterion of line shifts proves that dust is still present and is absorbing more strongly than ever; (ii) the I magnitude decreases faster than the other ones after day ∼1700; (iii) the 1.3mm flux is constant at about 9mJy, and comes most probably from free-free emission produced by the cooling of the former star envelope still weakly ionized. Previous analyses of the bolometric light curve until day 1444 are briefly reviewed. In spite of the large uncertainties, the flattening of the light curve, observed after day ∼900, extends until our latest data points (day 2172). This can be explained by theoretical models including time-dependent effects due to long recombination and cooling times (Fransson and Kozma 1993). However, one cannot rule out the presence of a compact object such as a neutron star, radiating as a pulsar or accreting matter from a disk either continuously or intermittently.

The Dust

In order to understand many aspects of the observed behaviour of SN 1987A at later phases, one must appreciate the role of dust in the expanding ejecta of the supernova. Molecules such as CO and SiO were formed at a very early phase (<100 days after outburst) (Bouchet and Danziger 1993). Probably as a result of the presence of molecules, dust formed at approximately day 530 and has since continued to play a dominant role in absorbing much of the harder radiation and thermalizing it.

Type
Chapter
Information
Supernovae and Supernova Remnants
IAU Colloquium 145
, pp. 201 - 210
Publisher: Cambridge University Press
Print publication year: 1996

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Save book to Kindle

To save this book to your Kindle, first ensure coreplatform@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.

Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

Find out more about the Kindle Personal Document Service.

Available formats
×

Save book to Dropbox

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.

Available formats
×

Save book to Google Drive

To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.

Available formats
×