J/ApJ/900/11 Spectra of SN 2017eaw 545 & 900 days after explosion (Weil+, 2020)
Late-time Circumstellar Interaction of SN 2017eaw in NGC 6946.
Weil K.E., Fesen R.A., Patnaude D.J., Milisavljevic D.
<Astrophys. J., 900, 11 (2020)>
=2020ApJ...900...11W 2020ApJ...900...11W
ADC_Keywords: Supernovae; Spectra, optical
Keywords: Core-collapse supernovae ; Type II supernovae ; Circumstellar matter ;
Ejecta
Abstract:
SN 2017eaw, the tenth supernova observed in NGC6946, was a normal Type
II-P supernova with an estimated 11-13M☉ red supergiant
progenitor. Here we present nebular-phase spectra of SN 2017eaw at
+545 and +900days post-max, extending approximately 50-400days past
the epochs of previously published spectra. While the +545day spectrum
is similar to spectra taken between days +400 and +493, the +900day
spectrum shows dramatic changes both in spectral features and
emission-line profiles. The Hα emission is flat-topped and
boxlike with sharp blue and red profile velocities of ~-8000 and
+7500km/s. These late-time spectral changes indicate strong
circumstellar interaction with a mass-loss shell, expelled ∼1700yr
before explosion. SN 2017eaw's +900day spectrum is similar to those
seen for SN2004et and SN2013ej observed 2-3yr after explosion. We
discuss the importance of late-time monitoring of bright SNeII-P and
the nature of presupernova mass-loss events for SNII-P evolution.
Description:
Optical spectra of SN2017eaw were taken on 2018 November 7-9 using
Ohio State Multi-Object Spectrograph (OSMOS) and a 1" wide slit with a
red volume phase holographic (VPH) grism. Exposure times were 3000s or
4000s.
Using the Multi Mirrors Telescope (MMT) 6.5m equipped with Binospec,
we obtained a spectrum on 2019 October 29, approximately +900days
after explosion. Observations consisted of 3x1260s exposures with a 1"
slit and the 270 line grating with 1.23" seeing and thin cirrus.
Objects:
-------------------------------------------------
RA (2000) DE Designation(s)
-------------------------------------------------
20 34 44.24 +60 11 36.0 SN2017eaw = SN 2017eaw
-------------------------------------------------
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
fig1a.dat 24 3756 Late-time nebular phase spectra SN 2017eaw at 545d
fig1b.dat 24 2615 Late-time nebular phase spectra SN 2017eaw at 900d
--------------------------------------------------------------------------------
See also:
J/MNRAS/372/1315 : UBVRI photometry of SN 2004et (Sahu+, 2006)
J/MNRAS/395/1409 : Type II-P SN progenitor constraints (Smartt+, 2009)
J/A+A/553/A104 : LHA 120-N49 supernova remnant maps (Melnik+, 2013)
J/MNRAS/438/L101 : First month on SN 2013ej (Valenti+, 2014)
J/MNRAS/449/1876 : Photometric observations of SN PTF11iqb (Smith+, 2015)
J/MNRAS/459/3939 : Type II supernova light curves (Valenti+, 2016)
J/AJ/156/18 : APOGEE DR14 Binary comp. evolved stars (Price-Whelan+, 2018)
J/ApJ/885/43 : UBVRI & ugriz photo. of supernova SN 2017gmr (Andrews+,2019)
J/MNRAS/487/832 : BVRI photometry of the Type II-P SN 2017eaw (Buta+, 2019)
J/ApJ/875/85 : Optical search SNRs in NGC6946 with WIYN & GMOS (Long+,2019)
J/ApJ/875/136 : BVRI, spectra & IR obs. type II-P SN2017eaw (Van Dyk+, 2019)
Byte-by-byte Description of file: fig1[ab].dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 F10.5 0.1nm Wave Rest Wavelength in Angstroms (1)
12- 24 E13.6 --- Flux Flux in erg/cm2/s/Angstrom (1)
--------------------------------------------------------------------------------
Note (1): Data at +545day obtained with the MDM OSMOS Red VPH Grism.
Data at +900day obtained with the MMT Binospec 270 line grating.
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 26-Oct-2021