J/MNRAS/488/803 Identification and confirmation of NGC 3344 SNRs (Moumen+, 2019)
3D optical spectroscopic study of NGC 3344 with SITELLE
I. Identification and confirmation of supernova remnants.
Moumen I., Robert C., Devost D., Martin R.P., Rousseau-Nepton L.,
Drissen L., Martin T.
<Mon. Not. R. Astron. Soc., 488, 803-829 (2019)>
=2019MNRAS.488..803M 2019MNRAS.488..803M (SIMBAD/NED BibCode)
ADC_Keywords: Supernova remnants ; Spectroscopy ; Velocity dispersion ; Optical
Keywords: techniques: imaging spectroscopy - ISM: supernova remnants -
galaxies: individual: NGC 3344 - galaxies: spiral
Abstract:
We present the first optical identification and confirmation of a
sample of supernova remnants (SNRs) in the nearby galaxy NGC 3344.
Using high spectral and spatial resolution data, obtained with the
CFHT imaging Fourier transform spectrograph SITELLE, we identified
about 2200 emission line regions, many of which are HII regions,
diffuse ionized gas regions, and also SNRs. Considering the stellar
population and diffuse ionized gas background, which are quite
important in NGC 3344, we have selected 129 SNR candidates based on
four criteria for regions where the emission lines flux ratio
[SII]/Hα≥0.4. Emission lines of [OII]λ3727, Hβ,
[OIII]λλ4959,5007, Hα,
[NII]λλ6548,6583, and [SII]λλ6716,6731
have been measured to study the ionized gas properties of the SNR
candidates. We adopted a self-consistent spectroscopic analysis, based
on Sabbadin plots and Baldwin, Phillips & Terlevich diagrams, to
confirm the shock-heated nature of the ionization mechanism in the
candidates sample. With this analysis, we end up with 42 Confirmed
SNRs, 45 Probable SNRs, and 42 Less likely SNRs. Using shock models,
the confirmed SNRs seem to have a metallicity ranging between Large
Magellanic Cloud and 2xsolar. We looked for correlations between the
size of the confirmed SNRs and their emission lines ratios, their
galaxy environment, and their galactocentric distance: We see a trend
for a metallicity gradient among the SNR population, along with some
evolutionary effects.
Description:
NGC 3344 was observed in 2016 March (RUNID: 16AH41; PI: R.P. Martin)
with the imaging Fourier transform spectrometer (iFTS) SITELLE
(Drissen et al. 2010SPIE.7735E..0BD, 2019MNRAS.485.3930D 2019MNRAS.485.3930D) installed on
the 3.6-m Canada-France-Hawaii Telescope (CFHT).
With a large 11arcminx11arcmin field of view (FoV) and a
seeing-limited spatial resolution sampled at 0.32arcsec, SITELLE
allows us to obtain more than 4 million spectra in the wavelength
range from 350 to 900nm. In the case of NGC 3344, the seeing was
typically 0.8arcsec. We selected the three filters SN1 (365-385nm),
SN2 (480-520nm), and SN3 (651-685nm) in order to get the strong
emission lines useful to study the ionized gas properties
([OII]λ3727, [OIII]λλ4959,5007, Hβ,
[NII]λλ6548,6584, Hα, and
[SII]λλ6716,6731).
Our systematic analysis using criteria (related to the physics and
morphology of the emission regions), reveals 129 SNR candidates that
are classified in three categories: confirmed (42), probable (44), and
less likely (43) SNRs. Table B1 gives the SNR candidates properties
and Table B2 lists all the emission lines integrated flux for the 129
candidates.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tableb1.dat 79 129 Catalogue of SNR candidates in NGC 3344
tableb2.dat 162 129 Emission lines fluxes of the SNR candidates in
NGC 3344 corrected for the background
contribution
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Byte-by-byte Description of file: tableb1.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Source name (SNR-CNNNN)
11 A1 --- f_Name [abc] Flag on name (1)
13- 14 I2 h RAh Right ascension (J2000)
16- 17 I2 min RAm Right ascension (J2000)
19- 23 F5.2 s RAs Right ascension (J2000)
25 A1 --- DE- Declination sign (J2000)
26- 27 I2 deg DEd Declination (J2000)
29- 30 I2 arcmin DEm Declination (J2000)
32- 36 F5.2 arcsec DEs Declination (J2000)
38- 45 E8.3 mW/m2 FHa Integrated Hα flux
47- 49 I3 pc Size Region diameter (2)
51- 54 F4.2 kpc GCD Galactocentric distance
56- 59 F4.1 --- R Correlation coefficient of the emission region
pseudo-Voight profile
61- 64 F4.2 --- [SII]/Ha ([SII]λ6716+[SII]λ6731)/Hα
flux ratio
66- 69 F4.2 --- e_[SII]/Ha Error on [SII]/Ha
71- 74 F4.1 km/s sigma ? Velocity dispersion
76- 79 F4.1 km/s e_sigma ? Error on sigma
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Note (1): Flag as follows :
a = Confirmed SNR (42/129)
b = Probable SNR (44/129)
c = Less likely SNR (43/129)
Note (2): The size parameter is represented by Σ through all the paper
and is simply equal to the FWHM of the pseudo-Voight profile obtained
for each region. This definition may underestimate the real size of a
region, but it allows a secure integrated flux measurement for the
region emission lines while avoiding an uncertainty due to the
immediate background contamination.
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Byte-by-byte Description of file: tableb2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Name Source name (SNR-CNNNN)
11- 18 E8.3 mW/m2 F3727 ? Integrated flux for [OII]λ3727 emission
line (1)
20- 26 E7.2 mW/m2 e_F3727 ? Error on F3727
28- 35 E8.3 mW/m2 FHb ? Integrated flux for Hβ emission line (1)
37- 43 E7.2 mW/m2 e_FHb ? Error on FHb
45- 52 E8.3 mW/m2 F4959 ? Integrated flux for [OIII]λ4959
emission line (1)
54- 60 E7.2 mW/m2 e_F4959 ? Error on F4959
62- 69 E8.3 mW/m2 F5007 ? Integrated flux for [OIII]λ5007
emission line (1)
71- 77 E7.2 mW/m2 e_F5007 ? Error on F5007
79- 86 E8.3 mW/m2 F6548 ? Integrated flux for [NII]λ6548 emission
line (1)
88- 94 E7.2 mW/m2 e_F6548 ? Error on F6548
96-103 E8.3 mW/m2 FHa Integrated flux for Hα emission line (1)
105-111 E7.2 mW/m2 e_FHa Error on FHa
113-120 E8.3 mW/m2 F6583 ? Integrated flux for [NII]λ6583 emission
line (1)
122-128 E7.2 mW/m2 e_F6583 ? Error on F6583
130-137 E8.3 mW/m2 F6716 Integrated flux for [SII]λ6716 emission
line (1)
139-145 E7.2 mW/m2 e_F6716 Error on F6716
147-154 E8.3 mW/m2 F6731 Integrated flux for [SII]λ6731 emission
line (1)
156-162 E7.2 mW/m2 e_F6731 Error on F6731
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Note (1): Integrated flux for all the emission lines measured in the SITELLE
SN1, SN2, and SN3 filters, after the subtraction of the global
background
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 24-Nov-2022