2013ApJ...767...98Z


C.D.S. - SIMBAD4 rel 1.7 - 2020.02.18CET04:20:04

2013ApJ...767...98Z - Astrophys. J., 767, 98 (2013/April-3)

High-resolution radio observations of the remnant of SN 1987A at high frequencies.

ZANARDO G., STAVELEY-SMITH L., NG C.-Y., GAENSLER B.M., POTTER T.M., MANCHESTER R.N. and TZIOUMIS A.K.

Abstract (from CDS):

We present new imaging observations of the remnant of Supernova (SN) 1987A at 44 GHz, performed in 2011 with the Australia Telescope Compact Array (ATCA). The 0.''35x0.''23 resolution of the diffraction-limited image is the highest achieved to date in high-dynamic range. We also present a new ATCA image at 18 GHz derived from 2011 observations, which is super-resolved to 0.''25. The flux density is 40±2 mJy at 44 GHz and 81±6 mJy at 18 GHz. At both frequencies, the remnant exhibits a ring-like emission with two prominent lobes, and an east-west brightness asymmetry that peaks on the eastern lobe. A central feature of fainter emission appears at 44 GHz. A comparison with previous ATCA observations at 18 and 36 GHz highlights higher expansion velocities of the remnant's eastern side. The 18-44 GHz spectral index is α = -0.80 (Sν∝να). The spectral index map suggests slightly steeper values at the brightest sites on the eastern lobe, whereas flatter values are associated with the inner regions. The remnant morphology at 44 GHz generally matches the structure seen with contemporaneous X-ray and Hα observations. Unlike the Hα emission, both the radio and X-ray emission peaks on the eastern lobe. The regions of flatter spectral index align and partially overlap with the optically visible ejecta. Simple free-free absorption models suggest that emission from a pulsar wind nebula or a compact source inside the remnant may now be detectable at high frequencies or at low frequencies if there are holes in the ionized component of the ejecta.

Abstract Copyright:

Journal keyword(s): acceleration of particles - circumstellar matter - ISM: supernova remnants - radiation mechanisms: non-thermal - radio continuum: general - supernovae: individual: SN 1987A

Simbad objects: 7

goto Full paper

goto View the reference in ADS

Number of rows : 7

N Identifier Otype ICRS (J2000)
RA
ICRS (J2000)
DEC
Mag U Mag B Mag V Mag R Mag I Sp type #ref
1850 - 2020
#notes
1 NAME LMC G 05 23 34.6 -69 45 22     0.4     ~ 14539 1
2 ICRF J052930.0-724528 QSO 05 29 30.04217690 -72 45 28.5072742   19.61   17.895   ~ 76 1
3 NAME SNR 1987A SNR 05 35 28.0 -69 16 11           ~ 34 0
4 SN 1987A SN* 05 35 28.020 -69 16 11.07   4.75 4.81     SN.IIPec 4415 2
5 QSO J0635-7516 QSO 06 35 46.5080299 -75 16 16.815501   15.96 15.75 15.82   ~ 504 1
6 ICRF J193925.0-634245 Sy2 19 39 25.02671 -63 42 45.6255   18.87 18.37 17.64   ~ 936 1
7 NAME Cas A SNR 23 23 24.000 +58 48 54.00           ~ 2362 1

    Equat.    Gal    SGal    Ecl

To bookmark this query, right click on this link: simbad:objects in 2013ApJ...767...98Z and select 'bookmark this link' or equivalent in the popup menu


2020.02.18-04:20:04

© Université de Strasbourg/CNRS

    • Contact