J/A+A/675/A73 SN 2018xx and SN 2019gbx light curves (Li+, 2023)
A comparative analysis of type Ia supernovae 2018xx and 2019gbx.
Li Y., Zheng S., Zeng X., Wang X., Burke J., Pellegrino C., Esamdin A.,
Lin X., Wang Y., Iskandar A., Zhang J., Wei P., Bird S.A., Zeng S.,
Huang Y., Howell D.A., Bostroem K.A., McCully C., Hiramatsu D.,
Hosseinzadeh G., Li W., Zhang T., Wang L., Zhou G.
<Astron. Astrophys. 675, A73 (2023)>
=2023A&A...675A..73L 2023A&A...675A..73L (SIMBAD/NED BibCode)
ADC_Keywords: Supernovae ; Photometry, UBVRI ; Photometry, SDSS ;
Photometry, ultraviolet
Keywords: supernovae: general - supernovae: individual: SN 2018xx -
supernovae: individual: SN 2019gbx
Abstract:
We present a comparative study of two nearby type Ia supernovae
(SNe Ia), 2018xx and 2019gbx, that exploded in NGC 4767 and
MCG-02-33-017 at a distance of 48 Mpc and 60 Mpc, respectively. The
B-band light curve decline rate for SN 2018xx is estimated to be
1.48±0.07mag and for SN 2019gbx it is 1.37±0.07mag. Despite the
similarities in photometric evolution, quasi-bolometric luminosity,
and spectroscopy between these two SNe Ia, SN 2018xx has been found to
be fainter by about 0.38mag in the Bband and has a lower 56Ni yield.
Their host galaxies have similar metallicities at the SN location,
indicating that the differences between these two SNe Ia may be
associated with the higher progenitor metallicity of SN 2018xx.
Further inspection of the near maximum-light spectra has revealed that
SN 2018xx has relatively strong absorption features near 4300Å
relative to SN 2019gbx. The application of the code TARDIS fitting to
the above features indicates that the absorption features near 4300Å
appear to be related to not only FeII/MgII abundance but possibly to
the other element abundances as well. Moreover, SN 2018xx shows a
weaker carbon absorption at earlier times, which is also consistent
with higher ejecta metallicity.
Description:
The photometric observations of SN 2018xx and SN 2019gbx
presented here were obtained with the one-meter telescopes of the Las
Cumbres Observatory (LCO) network for the Global Supernova Project
(Howell & Global Supernova Project 2017). The light curves of SN
2018xx in the UBVgri bands and those of SN 2019gbx in the BVgri bands
were sampled by LCO.
Ultraviolet (UV) and optical photometry of these two SNe
Ia were also observed with the Neil Gehrels Swift Observatory in six
bands, including the UVW1, UVW2, UVM2, U, B; and V filters.
Objects:
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RA (2000) DE Designation(s)
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12 53 48.23 -39 41 48.1 SN 2018xx = AT 2018xx
12 50 02.81 -14 46 00.1 SN 2019gbx = AT 2019gbx
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 119 41 Photometric standards in the SN 2018xx field
tablea2.dat 119 14 Photometric standards in the SN 2019gbx field
tableb1.dat 133 43 Optical and UV photometric observations of
SN 2018xx obtained from LCO and Swift telescopes
tableb2.dat 133 29 Optical and UV photometric observations of
SN 2019gbx obtained by LCO and Swift telescopes
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Byte-by-byte Description of file: tablea1.dat tablea2.dat
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Bytes Format Units Label Explanations
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1- 7 F7.3 deg RAdeg Right ascension (J2000)
9- 15 F7.3 deg DEdeg Declination (J2000)
17- 22 F6.3 mag Umag U band magnitude
24- 28 F5.3 mag e_Umag Uncertainty in Umag
30- 35 F6.3 mag Bmag B band magnitude
37- 41 F5.3 mag e_Bmag Uncertainty in Bmag
43- 48 F6.3 mag Vmag V band magnitude
50- 54 F5.3 mag e_Vmag Uncertainty in Vmag
56- 61 F6.3 mag Rmag R band magnitude
63- 67 F5.3 mag e_Rmag Uncertainty in Rmag
69- 74 F6.3 mag Imag I band magnitude
76- 80 F5.3 mag e_Imag Uncertainty in Imag
82- 87 F6.3 mag gmag g band magnitude
89- 93 F5.3 mag e_gmag Uncertainty in gmag
95-100 F6.3 mag rmag r band magnitude
102-106 F5.3 mag e_rmag Uncertainty in rmag
108-113 F6.3 mag imag i band magnitude
115-119 F5.3 mag e_imag Uncertainty in imag
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Byte-by-byte Description of file: tableb1.dat tableb2.dat
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Bytes Format Units Label Explanations
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1- 8 F8.2 d MJD Modified Julian Date of observation
(JD=2400000.5)
10- 16 F7.2 d Phase Days relative to
MJD = 58647.39 for SN 2018xx (tableb1.dat),
MJD = 58184.29 for SN 2019gbx (tableb2.dat)
18- 23 F6.3 mag Bmag ?=99.999 B band magnitude
25- 29 F5.3 mag e_Bmag ?=9.999 Uncertainty in Bmag
31- 36 F6.3 mag Vmag ?=99.999 V band magnitude
38- 42 F5.3 mag e_Vmag ?=9.999 Uncertainty in Vmag
44- 49 F6.3 mag Umag ?=99.999 U band magnitude
51- 55 F5.3 mag e_Umag ?=9.999 Uncertainty in Umag
57- 62 F6.3 mag gmag ?=99.999 g band magnitude
64- 68 F5.3 mag e_gmag ?=9.999 Uncertainty in gmag
70- 75 F6.3 mag rmag ?=99.999 r band magnitude
77- 81 F5.3 mag e_rmag ?=9.999 Uncertainty in rmag
83- 88 F6.3 mag imag ?=99.999 i band magnitude
90- 94 F5.3 mag e_imag ?=9.999 Uncertainty in imag
96-101 F6.3 mag UVM2mag ?=99.999 UVM2 band magnitude
103-107 F5.3 mag e_UVM2mag ?=9.999 Uncertainty in UVM2mag
109-114 F6.3 mag UVW2mag ?=99.999 UVW2 band magnitude
116-120 F5.3 mag e_UVW2mag ?=9.999 Uncertainty in UVW2mag
122-127 F6.3 mag UVW1mag ?=99.999 UVW1 band magnitude
129-133 F5.3 mag e_UVW1mag ?=9.999 Uncertainty in UVW1mag
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Acknowledgements:
Xiangyun Zen, xyzeng2018(at)ctgu.edu.cn
YangYang Li, liyangyang11223(at)163.com
(End) Patricia Vannier [CDS] 31-May-2023