J/A+A/708/A270 Characterization of type Ibn SNe (Farias+, 2026)
Characterization of type Ibn SNe.
Farias D., Gall C., Villar V.A., Auchettl K., de Soto K.M., Gagliano A.,
Hoogendam W.B., Narayan G., Sedgewick A., Yadavalli S.K., Zenati Y.,
Angus C.R., Davis K.W., Hjorth J., Jacobson-Galan W.V., Jones D.O.,
Kilpatrick C.D., Bustamante Rosell M.J., Coulter D.A., Dimitriadis G.,
Foley R.J., Gangopadhyay A., Gao H., Huber M.E., Izzo L., Johnson J.L.,
Piro A.L., Rest A., Rojas-Bravo C., Siebert M.R., Taggart K., Tinyanont S.
<Astron. Astrophys. 708, A270 (2026)>
=2026A&A...708A.270F 2026A&A...708A.270F (SIMBAD/NED BibCode)
ADC_Keywords: Supernovae ; Photometry ; Optical ; Ultraviolet ; Spectroscopy
Keywords: circumstellar matter - supernovae: general - stars: winds, outflows -
stars: Wolf-Rayet
Abstract:
Type Ibn supernovae (SNe) are characterized by narrow helium (He i)
lines from photons produced by the unshocked circumstellar material
(CSM). About 80 SNe Ibn have been discovered to date, and only a
handful have extensive observational records. Thus, many open
questions regarding the progenitor system and the origin of the CSM
remain.
Here we investigate potential correlations between the spectral
features of the prominent HeI λ5876Å line and the optical
and X-ray light curve properties of SNe Ibn.
We compile the largest sample of 61 SNe Ibn to date, of which 24 SNe
have photometric and spectroscopic data from the Young Supernova
Experiment and 37 SNe have archival data sets. We fit 24 SNe Ibn with
sufficient photometric coverage (B to z bands) using semi-analytical
models from MOSFiT.
We demonstrate that the light curves of SNe Ibn are more diverse than
previous analyses suggest, with absolute r-band peak magnitudes (rmax)
of -19.4±0.6mag and rise (from ∼10 days to peak, γ-10) and
decay-rates (from peak to +10 days; γ+10) of -0.08±0.06 and
0.08±0.03mag/day, respectively. We find that the majority of SNe Ibn
in the sub-sample are consistent with a low-energy explosion
(<1051erg) of a star with a compact envelope surrounded by
∼0.1M☉ of helium-rich CSM. The inferred ejecta masses are small
(Mej∼1M☉) and expand with a velocity of ∼5000km/s. Our
spectroscopic analysis shows that the mean velocity of the narrow
component of the HeI lines, associated to the CSM, peaks at ∼1100km/s.
The mean CSM and ejecta masses inferred for a sub-sample of SNe Ibn
indicate that their progenitors are not massive (∼10M☉), single
stars at the moment of explosion, but are likely binary systems. This
agrees with the detection of potential companion stars of SNe Ibn
progenitors, and the inferred CSM properties from stellar evolution
models.
Description:
We present a comprehensive analysis of a rich set of photometric and
spectroscopic data of 24 SNe Ibn (F25 sample) observed by the Young
Supernova Experiment between 2019 and 2023.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tabled3.dat 108 24 Summary of type Ibn SNe in the F25 sample
spec_tab.dat 58 81 Log of spectroscopic observations of Type Ibn
SNe in the F25 sample (table D2)
spec_pro.dat 51 59 Minimum and maximum velocity of the narrow and
broad components of He I 5876{A}A line of
59 SNe Ibn (table D7)
csi.dat 229 24 Inferred values of the parameters of the CSI
model for Type Ibn SNe in the MOSFiT sample
(table D4)
rdcsi.dat 282 24 *Inferred values of the parameters of the RD+CSI
model for Type Ibn SNe in the MOSFiT sample
(table D5)
phot.dat 51 1817 Photometric data of the Type Ibn SNe in the
F25 sample (table D1)
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Note on rdcsi.dat: The parameter value corresponds to the 50th percentile
(median) of the marginalized distribution of the parameter from MOSFiT.
The lower and upper uncertainties correspond to the 50th-16th and 84th-50th
percentiles of such distribution, respectively.
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Byte-by-byte Description of file: tabled3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 11 A11 --- Name Name of the supernova
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- 62 A25 --- Host Host Galaxy
64- 71 F8.2 d MJD Nodified Julain date
73- 78 F6.4 mag E(B-V)MW Mean value of E(B-V) from
Schlafly & Finkbeiner (2011ApJ...737..103S 2011ApJ...737..103S)
80- 83 F4.2 mag E(B-V)host ?=- Host E(B-V) (1)
85- 88 F4.2 mag E_E(B-V)host ? Host E(B-V) upper error
90- 93 F4.2 mag e_E(B-V)host ? Host E(B-V) lower error
95-100 F6.4 --- z Redshift
102-104 A3 --- X-ray [Yes No] SN was observed in X-ray ?
106-108 A3 --- MOSFiT [Yes No] SN has been modeled using MOSFiT ?
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Note (1): Details of the host extinction estimate are described Sect. 3.3.
The extinction in R/r-like bands was estimated directly from the posterior
samples of E(B-V)host instead of the value tabulated here.
Reported values for SN 2018jmt are retrieved from
Castro-Segura et al. (Transient Name Server Classification Report,
2018-2064, 1), Vallely et al. (2021MNRAS.500.5639V 2021MNRAS.500.5639V) and
Wang et al. (22024A&A...691A.156W),
Reported values for SN 2022ablq are retrieved from Stanek (2022, Transient
Name Server Discovery Report, 2022-3421, 1),
Fulton et al. (Transient Name Server Classification Report, 2022-3486, 1,
and Transient Name Server Classification Report, 2022-3522, 1)
Charalampopoulos et al. (2023, Transient Name Server Classification Report,
2023-454, 1) and Pellegrino et al. (2024ApJ...977....2P 2024ApJ...977....2P)
Reported values for SN 2023emq are retrieved from Tonry et al.
(2023, Transient Name Server Discovery Report, 2023-698, 1),
Pellegrino et al. (2023, Transient Name Server Classification Report,
2023-725, 1) and Pursiainen et al. (2023ApJ...959L..10P 2023ApJ...959L..10P).
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Byte-by-byte Description of file: spec_tab.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 11 A11 --- Name Name of the supernova
13- 22 A10 "date" Date Observation date
24- 27 I4 d Phase Phase (1)
29- 38 A10 0.1nm Range Wavelength range of the spectrograph in Å
40- 44 F5.2 0.1nm Disp Dispersion of the spectrograph
46- 55 A10 --- Inst Name of the instrument
56 A1 --- n_Inst [+] Note on Inst (2)
58 A1 --- Analysis [VX] Analysis (3)
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Note (1): Phases estimated with respect to MJDmax (Table D.8).
Note (2): + indicates that the spectrum is retrieved directly from WISeREP.
Note (3): Note as follows:
V = corresponding spectrum was utilized for the spectroscopic analysis
in Sect. 6.
X = corresponding spectrum was not utilized for the spectroscopic analysis
in Sect. 6.
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Byte-by-byte Description of file: spec_pro.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- Name Name of the supernova
18 A1 --- l_Vnarrow [~] Limit flag on Vnarrow
19- 22 I4 km/s Vnarrow ?=- Velocity of the narrow component of
HeI 5876Å
24- 26 I3 km/s E_Vnarrow ? Velocity of the narrow component of
HeI 5876Å error (upper value)
28- 30 I3 km/s e_Vnarrow ? Velocity of the narrow component of
HeI 5876Å error (lower value)
32 A1 --- l_Vbroad [~] Limit flag on Vbroad
33- 36 I4 km/s Vbroad ?=- Velocity of the broad component of
HeI 5876Å
38- 41 I4 km/s E_Vbroad ? Velocity of the broad component of
HeI 5876Å (upper value)
43- 46 I4 km/s e_Vbroad ? Velocity of the broad component of
HeI 5876Å (lower value)
48- 51 A4 --- Refs References (1)
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Note (1): References as follows:
1 = Pastorello et al., 2015MNRAS.449.1921P 2015MNRAS.449.1921P
2 = This work
3 = Hosseinzadeh et al., 2017ApJ...836..158H 2017ApJ...836..158H
4 = Smartt et al., 2016ApJ...827L..40S 2016ApJ...827L..40S
5 = Wang et al., 2020ApJ...900...83W 2020ApJ...900...83W
6 = Karamehmetoglu et al., 2021A&A...649A.163K 2021A&A...649A.163K
7 = Wang et al., 2024A&A...691A.156W 2024A&A...691A.156W
8 = Pellegrino et al., 2022ApJ...926..125P 2022ApJ...926..125P
9 = Ben-Ami et al., 2023ApJ...946...30B 2023ApJ...946...30B
10 = Gangopadhyay et al., 2020ApJ...889..170G 2020ApJ...889..170G
11 = Gangopadhyay et al., 2022ApJ...930..127G 2022ApJ...930..127G
12 = Kool et al., 2021A&A...652A.136K 2021A&A...652A.136K
13 = Wang et al., 2024MNRAS.530.3906W 2024MNRAS.530.3906W
14 = Cai, in prep.
15 = Pellegrino et al., 2024ApJ...977....2P 2024ApJ...977....2P
16 = Pursiainen et al., 2023ApJ...959L..10P 2023ApJ...959L..10P
17 = Vallely et al., 2018MNRAS.475.2344V 2018MNRAS.475.2344V
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Byte-by-byte Description of file: csi.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- Name Name of the supernova
18- 22 F5.2 0.1Msun Mass CSM mass
24- 29 F6.2 0.1Msun E_Mass CSM mass upper error
31- 35 F5.2 0.1Msun e_Mass CSM mass lower error
37- 41 F5.2 Msun Mej Ejecta mass
43- 47 F5.2 Msun E_Mej Ejecta mass upper error
49- 52 F4.2 Msun e_Mej Ejecta mass lower error
54- 57 F4.2 --- n Index of the density profile of the
outer ejecta
59- 62 F4.2 --- E_n Index of the density profile of the
outer ejecta upper error
64- 67 F4.2 --- e_n Index of the density profile of the
outer ejecta lower error
69- 73 F5.2 10-2mag AVhost Extinction in V-band
75- 79 F5.2 10-2mag E_AVhost Extinction in V-band upper error
81- 84 F4.2 10-2mag e_AVhost Extinction in V-band lower error
86- 90 F5.2 10+14cm R0 Inner radius of the CSM
92- 95 F4.2 10+14cm E_R0 Inner radius of the CSM upper error
97-100 F4.2 10+14cm e_R0 Inner radius of the CSM lower error
102-107 F6.2 [g/cm3] logrho CSM density
109-112 F4.2 [g/cm3] E_logrho CSM density upper error
114-117 F4.2 [g/cm3] e_logrho CSM density lower error
119-122 F4.2 --- s Index of the density profile of the CSM
124-127 F4.2 --- E_s Index of the density profile of the CSM
upper error
129-132 F4.2 --- e_s Index of the density profile of the CSM
lower error
134-139 F6.2 d TExpl Explosion time (1)
141-144 F4.2 d E_TExpl Explosion time upper error
146-149 F4.2 d e_TExpl Explosion time lower error
151-154 F4.2 mag sigma White noise
156-159 F4.2 mag E_sigma White noise upper error
161-164 F4.2 mag e_sigma White noise lower error
166-169 F4.2 10+3km/s vej Ejecta velocity
171-174 F4.2 10+3km/s E_vej Ejecta velocity upper error
176-179 F4.2 10+3km/s e_vej Ejecta velocity lower error
181-184 F4.2 cm2/g kappa Optical opacity
186-189 F4.2 cm2/g E_kappa Optical opacity upper error
191-194 F4.2 cm2/g e_kappa Optical opacity lower error
196-200 F5.2 Msun/yr dM/dt Mass-loss rate (2)
202-205 F4.2 Msun/yr E_dM/dt Mass-loss rate upper error
207-210 F4.2 Msun/yr e_dM/dt Mass-loss rate lower error
212-216 F5.2 10+16cm Router Outer radius of the CSM (3)
218-223 F6.2 10+16cm E_Router Outer radius of the CSM upper error
225-229 F5.2 10+16cm e_Router Outer radius of the CSM loer error
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Note (1): The lower boundary of the distribution of texp is the only value
that changes between each SN modeling. The prior distributions of the MOSFiT
modeling are either Uniform (U) or log-Uniform (logU), except for the
ejecta velocity which is Gaussian (G). The specific prior distribution per
parameter of the CSI model are κ: U(0.1,0.4) [cm2/g];
MCSM: logU(10-3,30) [M☉]; Mej: logU(0.1,30) [M☉];
n: U(7,12); nH,host: logU(1016,6 x 1021) [cm-2];
R0: logU(2 x 1012, 5 x 1015) [cm];
ρCSM: logU(10-17,10-10) [g/cm3];
s: logU(0,2); Tmin: logU(1000,20000) [K];
texp :U(-20,0) [days], and vej:logG(µ=6000,σ=2000) [km/s].
Note (2): Average mass-loss rates are estimated from Eq. 2 assuming vw as the
narrow component (vnarrow) of the Hei λ5876 Å line in Table D.7.
See Sect.6 for more details.
Note (3): The outer radius of the CSM (R_outer, CSM_) is estimated from Eq. 3.
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Byte-by-byte Description of file: rdcsi.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- Name Name of the supernova
18- 22 F5.2 0.1Msun Mass CSM mass
24- 28 F5.2 0.1Msun E_Mass CSM mass upper error
30- 34 F5.2 0.1Msun e_Mass CSM mass lower error
36- 40 F5.2 Msun Mej Ejecta mass
42- 46 F5.2 Msun E_Mej Ejecta mass upper error
48- 51 F4.2 Msun e_Mej Ejecta mass lower error
53- 57 F5.2 --- n Index of the density profile of the
outer ejecta
59- 62 F4.2 --- E_n Index of the density profile of the
outer ejecta upper error
64- 67 F4.2 --- e_n Index of the density profile of the
outer ejecta lower error
69- 74 F6.2 10-2mag AVhost Extinction in V-band
76- 80 F5.2 10-2mag E_AVhost Extinction in V-band upper error
82- 87 F6.2 10-2mag e_AVhost Extinction in V-band lower error
89- 93 F5.2 10+14cm R0 Inner radius of the CSM
95- 98 F4.2 10+14cm E_R0 Inner radius of the CSM upper error
100-103 F4.2 10+14cm e_R0 Inner radius of the CSM lower error
105-110 F6.2 g/cm3 logrho CSM density
112-115 F4.2 g/cm3 E_logrho CSM density upper error
117-120 F4.2 g/cm3 e_logrho CSM density lower error
122-125 F4.2 --- s Index of the density profile of the CSM
127-130 F4.2 --- E_s Index of the density profile of the CSM
upper error
132-135 F4.2 --- e_s Index of the density profile of the CSM
lower error
137-142 F6.2 d TExpl Explosion time (1)
144-147 F4.2 d E_TExpl Explosion time upper error
149-152 F4.2 d e_TExpl Explosion time lower error
154-157 F4.2 mag sigma White noise
159-162 F4.2 mag E_sigma White noise upper error
164-167 F4.2 mag e_sigma White noise lower error
169-173 F5.2 10+3km/s vej Ejecta velocity
175-178 F4.2 10+3km/s E_vej Ejecta velocity upper error
180-183 F4.2 10+3km/s e_vej Ejecta velocity lower error
185-188 F4.2 cm2/g kappa Optical opacity
190-193 F4.2 cm2/g E_kappa Optical opacity upper error
195-198 F4.2 cm2/g e_kappa Optical opacity lower error
200-204 F5.2 cm2/g kappa-gamma gamma-ray opacity
206-209 F4.2 cm2/g E_kappa-gamma gamma-ray opacity upper error
211-214 F4.2 cm2/g e_kappa-gamma gamma-ray opacity lower error
216-220 F5.2 % fNi Fraction of nickel mass in the SN ejecta
222-226 F5.2 % E_fNi Fraction of nickel mass in the SN ejecta
upper error
228-232 F5.2 % e_fNi Fraction of nickel mass in the SN ejecta
lower error
234-237 F4.2 10-2Msun MNi Nickel mass (2)
239-242 F4.2 10-2Msun E_MNi Nickel mass upper error
244-247 F4.2 10-2Msun e_MNi Nickel mass lower error
249-253 F5.2 Msun/yr dM/dt Mass-loss rate (3)
255-258 F4.2 Msun/yr E_dM/dt Mass-loss rate upper error
260-263 F4.2 Msun/yr e_dM/dt Mass-loss rate lower error
265-269 F5.2 10+16cm Router Outer radius of the CSM (4)
271-276 F6.2 10+16cm E_Router Outer radius of the CSM upper error
278-282 F5.2 10+16cm e_Router Outer radius of the CSM lower error
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Note (1): Similar to Table D.4, the lower boundary of the distribution of texp
is the only value that changes between each SN modeling. The prior
distributions of the shared parameters between the CSI and RD+CSI models
remain unchanged. The RD+CSI model contains two additional parameters:
the γ-ray opacity (κγ) and the fraction of the nickel mass
in the SN ejecta (fNi). The prior distributions of each parameter are
κγ:logU(0.1,10000) [cm2/g], and fNi:logU(10-5,1).
Note (2): Nickel mass (MNi) is estimated as MNi=fNi x Mej, where fNi
is a free parameter in the RD+CSI model corresponding to the fraction of
nickel mass in the SN ejecta.
Note (3): Average mass-loss rates are estimated from Eq. 2 assuming vw as the
narrow component (vnarrow) in Table D.7.
Note (4): Outer radius of the CSM is estimated from Eq. 3.
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Byte-by-byte Description of file: phot.dat
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Bytes Format Units Label Explanations
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1- 11 A11 --- Name Name of the supernova
13- 22 F10.4 d MJD Modified Julian Day
24- 29 F6.3 mag mag Magnitude in band (AB)
31- 35 F5.3 mag e_mag Error in magnitude in band (AB)
37- 40 A4 --- Band Photometric band for the magnitude (1)
42- 51 A10 --- Inst Facility/Instrument
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Note (1): Band could be UBV, ugriz w y, up gp rp ip, o c, UVM2 UVW1 UVW2.
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Acknowledgements:
Diego Farias, diegofariash(at)gmail.com
License: CC-BY-4.0 [see https://spdx.org/licenses/]
(End) Patricia Vannier [CDS] 09-Mar-2026