J/ApJ/917/97 Spectroscopic obs. of type Ibn ASASSN-14ms (Wang+, 2021)
ASASSN-14ms: the most energetic known explosion of a type Ibn supernova and its
physical origin.
Wang X., Lin W., Zhang J., Zhang T., Cai Y., Zhang K., Filippenko A.V.,
Graham M., Maeda K., Mo J., Xiang D., Xi G., Yan S., Wang L., Wang L.,
Kawabata K., Zhai Q.
<Astrophys. J., 917, 97 (2021)>
=2021ApJ...917...97W 2021ApJ...917...97W
ADC_Keywords: Supernovae; Spectra, optical
Keywords: Circumstellar dust ; Stellar mass loss
Abstract:
ASASSN-14ms may represent the most luminous Type Ibn supernova (SNIbn)
ever detected, with an absolute U-band magnitude brighter than
-22.0mag and a total bolometric luminosity >1.0x1044erg/s near
maximum light. The early-time spectra of this SN are characterized by
a blue continuum on which are superimposed narrow P Cygni profile
lines of HeI, suggesting the presence of slowly moving (∼1000km/s),
He-rich circumstellar material (CSM). At 1-2 months after maximum
brightness, the HeI line profiles become only slightly broader, with
blueshifted velocities of 2000-3000km/s, consistent with the CSM shell
being continuously accelerated by the SN light and ejecta. Like most
SNe Ibn, the light curves of ASASSN-14ms show rapid post-peak
evolution, dropping by ∼7mag in the V band over three months. Such a
rapid post-peak decline and high luminosity can be explained by
interaction between SN ejecta and helium-rich CSM of 0.9M☉ at a
distance of ∼1015cm. The CSM around ASASSN-14ms is estimated to
originate from a pre-explosion event with a mass-loss rate of
6.7M☉/yr (assuming a velocity of ∼1000km/s), which is consistent
with abundant He-rich material violently ejected during the late
Wolf-Rayet (WN9-11 or Opfe) stage. After examining the light curves
for a sample of SNe Ibn, we find that the more luminous ones tend to
have slower post-peak decline rates, reflecting that the observed
differences may arise primarily from discrepancies in the CSM
distribution around the massive progenitors.
Description:
We commenced optical photometry of ASASSN-14ms with different
instruments, including the 0.8m Tsinghua University-NAOC Telescope
(TNT) at Xinglong Observatory in China, the 2.4m telescope of Yunnan
Observatories at Lijiang Station (LJT) in China, and the 2.3m Bok
telescope of NAOA in the USA. These observations spanned from about
-2 to +130 days from maximum brightness.
In addition, ultraviolet (UV) and optical photometry from the
Ultra-Violet/Optical Telescope (UVOT) on board the Neil Gehrels Swift
Observatory was available at two epochs around maximum light.
Spectroscopic observations, spanning 2014-Dec-29 to 2015-Jun-21 were
collected using the Lijiang 2.4m telescope and YFOSC system, the
Xinglong 2.16m telescope (+BFOSC), and the Keck 10m telescope (+LRIS).
A journal of observations is given in Table 4.
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
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13 04 08.69 +52 18 46.4 ASASSN-14ms = ASASSN -14ms
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 107 12 Journal of spectroscopic observations of ASASSN-14ms
sp/* . 12 Individual spectrum in ASCII format
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See also:
II/5 : UBV Photometry of Bright Stars (Johnson+ 1966)
J/MNRAS/383/1485 : BVRI light curves of SN 2003jd (Valenti+, 2008)
J/MNRAS/416/3138 : SN 2009jf light curves (Valenti+, 2011)
J/ApJ/788/48 : X-ray through NIR photometry of NGC 2617 (Shappee+, 2014)
J/MNRAS/449/1921 : UV/optical/NIR phot. for Type Ibn SNe (Pastorello+, 2015)
J/MNRAS/453/3649 : Photometric data for ASASSN-15ed (Pastorello+, 2015)
J/MNRAS/449/1941 : Optical/NIR phot. of OGLE-2012-SN-006 (Pastorello+, 2015)
J/A+A/579/A40 : PESSTO catalog (Smartt+, 2015)
J/A+A/580/A131 : Circumstellar-interacting supernovae (Taddia+, 2015)
J/A+A/602/A93 : SN Type Ibn OGLE-2014-SN-131 LCs (Karamehmetoglu+, 2017)
J/ApJ/835/58 : PTF 12dam & iPTF 13dcc follow-up (Vreeswijk+, 2017)
J/ApJ/910/42 : LCs and spectroscopic obs. of AT2018cow (Xiang+, 2021)
Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 11 A11 "Y/M/D" Date Date of observation (UT)
13- 19 F7.2 d JD [7021.36/7194.9] Julian Date; JD-2450000
21- 27 F7.2 d Phase [-2.49/171.05] Phase relative to the epoch of
V-band maximum (JD=2457023.85)
29- 32 I4 s Exp [1200/3600] Exposure time
34- 55 A22 --- Tel Telescope+Instrument
57- 60 I4 0.1nm Lam1 [3000/4000] Lower wavelength range in Å
61 A1 --- --- [-]
62- 66 I5 0.1nm Lam2 [8750/10000] Upper wavelength range in Å
68-107 A40 --- File Name of the ASCII file in subdirectory "sp"
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Byte-by-byte Description of file: sp/*
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Bytes Format Units Label Explanations
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1- 16 E16.6 0.1nm lambda [3074.5/10346.3] Wavelength, Observed-frame,
in Angstrom units
18- 30 E13.4 cW/m2/nm Flux [/4e-15] Flux,
in erg/s/cm2/Angstrom units
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 11-Jan-2023