Properties of optically selected supernova remnant candidates in M33

Journal Article · Wed Oct 01 04:00:00 EDT 2014 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/793/2/134· OSTI ID:22370534

Lee, Jong Hwan

Narrowband images covering strong emission lines are efficient for surveying supernova remnants (SNRs) in nearby galaxies. Using the narrowband images provided by the Local Group Galaxy Survey, we searched for SNRs in M33. Culling the objects with enhanced [S II]/Hα and round morphology in the continuum-subtracted Hα and [S II] images, we produced a list of 199 sources. Among them, 79 are previously unknown. Their progenitor and morphology types were classified. A majority of the sample (170 objects) are likely remnants of core-collapse supernovae (SNe), and 29 are remnants of Type Ia SNe. The cumulative size distribution of these objects is found to be similar to that of the M31 remnants derived in a similar way. We obtain a power-law slope, α = 2.38 ± 0.05. Thus, a majority of the sources are considered to be in the Sedov-Taylor phase, consistent with previous findings. The histogram of the emission-line ratio ([S II]/Hα) of the remnants has two concentrations at [S II]/Hα ∼ 0.55 and ∼0.8, as in M31. Interestingly, L {sub X} (and L {sub 20cm}) of the compact center-bright objects are correlated with their optical luminosity. The remnants with X-ray emission have brighter optical surface brightnesses and smaller diameters than those without X-ray emission.

• OSTI ID: 22370534
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 793; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
BRIGHTNESS
CONCENTRATION RATIO
DISTRIBUTION
ELEMENT ABUNDANCE
EMISSION
GALAXIES
IMAGES
LUMINOSITY
SUPERNOVA REMNANTS
SUPERNOVAE
SURFACES
X RADIATION