J/A+A/700/A156 Magnitudes of five SNe Ibn (Wang+, 2025)
Massive stars exploding in a He-rich circumstellar medium. XI. Diverse evolution
of five Ibn SNe 2020nxt, 2020taz, 2021bbv, 2023utc and 2024aej.
Wang Z.-Y., Pastorello A., Cai Y.-Z., Fraser M., Reguitti A., Lin W.-L,
Tartaglia L., Andrew Howell D., Benetti S., Cappellaro E., Chen Z.-H.,
Elias-Rosa N., Farah J., Fiore A., Hiramatsu D., Kankare E., Li Z.-T.,
Lundqvist P., Mazzali P.A., McCully C., Mo J., Moran S., Newsome M.,
Padilla Gonzalez E., Pellegrino C., Peng Z.-H., Smartt S.J., Srivastav S.,
Stritzinger M.D., Terreran G., Tomasella L., Valerin G., Wang G.-J.,
Wang X.-F., de Boer T., Chambers K.C., Gao H., Guo F.-Z., Gutierrez C.P.,
Kangas T., Karamehmetoglu E., Li G.-C., Lin C.-C., Lowe T.B., Ma X.-R.,
Magnier E.A., Minguez P., Pei S.-P., Reynolds T.M., Wainscoat R.J., Wang B.,
Williams S., Wu C.-Y., Yan S.-Y., Zhang J.-J., Zhang X.-H., Zhu X.-J.
<Astron. Astrophys. 700, A156 (2025)>
=2025A&A...700A.156W 2025A&A...700A.156W (SIMBAD/NED BibCode)
ADC_Keywords: Supernovae ; Photometry, UBV ; Photometry, SDSS ;
Photometry, ultraviolet ; Optical ; Magnitudes
Keywords: circumstellar matter - supernovae: individual: SN 2020nxt -
supernovae: individual: SN 2020taz -
supernovae: individual: SN 2021bbv -
supernovae: individual: SN 2023utc -
supernovae: individual: SN 2024aej
Abstract:
We present the photometric and spectroscopic analysis of five Type Ibn
supernovae (SNe): SN 2020nxt, SN 2020taz, SN 2021bbv, SN 2023utc, and
SN 2024aej. These events share key observational features and belong
to a family of objects similar to the prototypical Type Ibn SN 2006jc.
The SNe exhibit rise times of approximately 10 days and peak absolute
magnitudes ranging from -16.5 to -19mag. Notably, SN 2023utc is the
faintest Type Ibn supernova discovered to date, with an exceptionally
low r-band absolute magnitude of -16.4mag. The pseudo-bolometric light
curves peak at (1-10)x1042erg/s, with total radiated energies on the
order of (1-10)x1048erg. Spectroscopically, these SNe display
relatively slow spectral evolution; the early spectra are
characterised by a hot blue continuum and prominent HeI emission
lines. Early spectra show blackbody temperatures exceeding 10000K,
with a subsequent decline in temperature during later phases. Narrow
HeI lines, indicative of unshocked circumstellar material (CSM), show
velocities of approximately 1000km/s. The spectra suggest that the
progenitors of these SNe underwent significant mass loss prior to the
explosion, resulting in a He-rich CSM. Light curve modelling yields
estimates for the ejecta mass (Mej) in the range 1-3M☉, with
kinetic energies (EKin) of (0.1-1)x1050erg. The inferred CSM mass
ranges from 0.2 to 1M☉. These findings are consistent with
expectations for core-collapse events arising from relatively massive,
envelope-stripped progenitors.
Description:
We conducted comprehensive multiband follow-up campaigns for SNe
2020nxt, 2020taz, 2021bbv, 2023utc, and 2024aej in the Johnson-Cousins
UBV and Sloan ugriz filters, with monitoring started shortly after the
SN discoveries.
Photometry tables for five Ibn supernovae (SN 2020nxt, SN 2020taz,
SN 2021bbv, SN 2023utc, SN 2024aej).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 99 5 Basic information for the five Ibn SN host galaxies
2020nxt.dat 54 336 Light curves of SN 2020nxt
2020taz.dat 54 210 Light curves of SN 2020taz
2021bbv.dat 54 130 Light curves of SN 2021bbv
2023utc.dat 54 151 Light curves of SN 2023utc
2024aej.dat 49 101 Light curves of SN 2024aej
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- SN SN name (YYYYaaa)
9- 33 A25 --- Host Host Galaxy
35- 40 F6.4 --- z Redshift
42- 47 F6.4 --- e_z Redshift error
50- 54 F5.1 Mpc Dist Distance
56- 59 F4.1 Mpc e_Dist Distance error
62- 66 F5.2 mag MOD Distance modulus
68- 71 F4.2 mag e_MOD Distance modulus error
74- 76 F3.1 kpc RDist Radial distance
78- 80 F3.1 kpc e_RDist Radial distance error
83- 87 F5.3 mag E(B-V)MW Reddening
89-99 A11 --- FileName Name of the light curve file
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Byte-by-byte Description of file: 20*.dat
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Bytes Format Units Label Explanations
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1- 10 A10 "date" Date Date of observation (YYYY/MM/DD)
12- 19 F8.2 d MJD Modified Julian Date
21- 24 A4 --- Filter Filter (1)
26- 29 A4 --- magType AB or Vega
31 A1 --- l_mag Limit flag on mag
32- 37 F6.3 mag mag Apparent magnitude in Filter
39- 43 F5.3 mag e_mag ?=- Error on apparent magnitude in Filter
45- 54 A10 --- Inst Instrument or Source
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Note (1): UBV, oc, ugriz, w, UVM2 UVW1 UVW2 for SN 2020nxt,
UBV(Ve), oc, ugriz, w for SN 2020taz,
UBV(Ve), oc, ugriz, w for SN 2021bbv,
UBV(Ve), oc, gri, w for SN 2023utc,
UBV(Ve), oc, gri for SN 2024aej.
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Acknowledgements:
Zi-Yang Wang, wangziyang(at)mail.bnu.edu.cn
(End) Patricia Vannier [CDS] 20-Jun-2025