J/ApJ/942/L18         0.9-18um obs. of SN 2021afdx         (Hosseinzadeh+, 2023)
JWST imaging of the Cartwheel galaxy reveals dust associated with SN 2021afdx.
    Hosseinzadeh G., Sand D.J., Jencson J.E., Andrews J.E., Shivaei I.,
    Bostroem K.A., Valenti S., Szalai T., Burke J., Howell D.A., McCully C.,
    Newsome M., Gonzalez E.P., Pellegrino C., Terreran G.
   <Astrophys. J., 942, L18 (2023)>
   =2023ApJ...942L..18H 2023ApJ...942L..18H
ADC_Keywords: Supernovae; Photometry; Infrared; Spectra, optical;
              Energy distributions; Radial velocities
Keywords: Core-collapse supernovae ; Supernovae ; Type II supernovae ;
          Dust formation
Abstract:
    We present near- and mid-infrared (0.9-18µm) photometry of
    supernova (SN) 2021afdx, which was imaged serendipitously with the
    James Webb Space Telescope (JWST) as part of its Early Release
    Observations of the Cartwheel Galaxy. Our ground-based optical
    observations show it is likely to be a Type IIb SN, the explosion of a
    yellow supergiant, and its infrared spectral energy distribution (SED)
    ∼200 days after explosion shows two distinct components, which we
    attribute to hot ejecta and warm dust. By fitting models of dust
    emission to the SED, we derive a dust mass of
    (3.8-0.3+0.5)x10-3M☉, which is the highest yet observed in
    a Type IIb SN but consistent with other Type II SNe observed by the
    Spitzer Space Telescope. We also find that the radius of the dust is
    significantly larger than the radius of the ejecta, as derived from
    spectroscopic velocities during the photospheric phase, which implies
    that we are seeing an infrared echo off of preexisting dust in the
    progenitor environment, rather than dust newly formed by the SN. Our
    results show the power of JWST to address questions of dust formation
    in SNe, and therefore the presence of dust in the early universe, with
    much larger samples than have been previously possible.
Description:
    SN 2021afdx was discovered by the Asteroid Terrestrial-impact Last
    Alert System (ATLAS) on 2021 November 23.308 UT at
    RAJ2000=00:37:42.580,DEJ2000=-33:43:25.28, 32" southeast of the center
    of the Cartwheel Galaxy (ESO 350-40). We downloaded the full survey
    light curve from the ATLAS Forced Photometry Server.
    We also obtained multiband follow-up photometry using the Sinistro
    cameras on Las Cumbres Observatory's network of 1m telescopes as part
    of the Global Supernova Project. We subtracted reference images of the
    field taken with the same telescopes on 2022 May 27, about 4 months
    after the SN had faded. We calibrated this photometry to the AAVSO
    Photometry All-Sky Survey (Henden+ 2009AAS...21440702H). B and V are
    reported in Vega magnitudes, and g, r, and i are reported in AB
    magnitudes.
    SN 2021afdx was classified as an SN II by the Advanced Extended Public
    ESO Spectroscopic Survey of Transient Objects (ePESSTO+;
    Smartt+ 2015, J/A+A/579/A40) based on a spectrum taken with the ESO
    Faint Object Spectrograph and Camera 2 (EFOSC2) on the New Technology
    Telescope on 2021 November 26.173 (Ragosta+ 2021TNSCR4035....1R 2021TNSCR4035....1R).
    We obtained six additional optical spectra using FLOYDS on Las Cumbres
    Observatory's 2m Faulkes Telescope South, which are logged in Table 1.
    We downloaded the JWST images of the Cartwheel Galaxy in 10 filters
    spanning 0.9-18um from the Mikulski Archive for Space Telescopes
    (Proposal 2727; PI: Pontoppidan; doi:10.17909/2n49-hx69) and performed
    aperture photometry. See Section 2.2.
Objects:
  --------------------------------------------------------------------------
      RA   (ICRS)   DE        Designation(s)                   (z)
  --------------------------------------------------------------------------
   00 37 41.11  -33 42 58.5   Cartwheel Galaxy = ESO 350-40    (z=0.030187)
   00 37 42.58  -33 43 25.2   SN 2021afdx = SN 2021afdx
  --------------------------------------------------------------------------
File Summary:
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 FileName    Lrecl  Records   Explanations
--------------------------------------------------------------------------------
ReadMe          80        .   This file
table1.dat      93        6   Spectroscopic observations and velocities
fig2a.dat       57      162   Ground-based optical and JWST-based infrared
                               of SN 2021afdx
fig2b.dat      104       19   Pseudo-bolometric light curve fits
                               with a blackbody SED
sp/*             .        6  *LCOGT/FLOYDS individual spectra of SN 2021afdx
                               in FITS format -- data behind Figure 3
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Note on sp/*: The files are all 3-dimensional PrimaryHDU (HDU=0) FITS
    files with four separate spectra in NAXIS3, containing
    BANDID1 = 'spectrum - background fit, weights variance, clean yes'
    BANDID2 = 'raw - background fit, weights none, clean no'
    BANDID3 = 'background - background fit'
    BANDID4 = 'sigma - background fit, weights variance, clean yes'
    The data shown in Figure 3 is from the first band, spectrum -
    background fit.
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See also:
 J/A+A/330/881    : Radial velocities of Cartwheel Galaxy (Amram+ 1998)
 J/ApJ/778/L19    : SN 2011dh (type IIb) 3.6 & 4.5um light curves (Helou+, 2013)
 J/MNRAS/438/L101 : First month on SN 2013ej (Valenti+, 2014)
 J/A+A/580/A142   : SN 2011dh. The first two years (Ergon+, 2015)
 J/other/Sci/348.413 : Sgr A East SNR multiwavelength images (Lau+, 2015)
 J/A+A/579/A40    : PESSTO catalog (Smartt+, 2015)
 J/MNRAS/459/3939 : Type II supernova light curves (Valenti+, 2016)
 J/ApJ/864/L20    : SN 2017eaw NIR spectroscopy (Rho+, 2018)
 J/ApJS/241/38    : A comprehensive analysis of Spitzer SNe (Szalai+, 2019)
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
   Bytes Format Units   Label  Explanations
--------------------------------------------------------------------------------
   1-  9 F9.3   d       MJD    [59550.49/59601.43] Modified Julian Date
  11- 13 A3     ---     Tel    Telescope ("FTS")
  15- 20 A6     ---     Inst   Instrument ("FLOYDS")
  22- 25 F4.1   d       Phase  [10.8/60.3] Phase (G1)
  27- 31 F5.2   Mm/s    VHa    [11.1/12.59]? Hα velocity
  33- 36 F4.2   Mm/s  e_VHa    [0.07/0.1]? VHa uncertainty
  38- 93 A56    ---     File   Name of the FITS file in subdirectory "sp";
                                column added by CDS
--------------------------------------------------------------------------------
Byte-by-byte Description of file: fig2a.dat
--------------------------------------------------------------------------------
   Bytes Format Units   Label   Explanations
--------------------------------------------------------------------------------
   1- 11 F11.5  d       MJD     [59387.6/59745.42] Modified Julian Date of
                                 observation (JD-2400000.5)
      13 A1     ---   l_omag    Limit flag on omag
  15- 20 F6.3   mag     omag    [17.98/23.95] Observed magnitude in Filter
  22- 26 F5.3   mag   e_omag    [0.004/0.2]? Uncertainty in omag,
                                 null if upper limit
  28- 33 A6     ---     Filter  Filter
  35- 48 A14    ---     Tel     Telescope ("Las Cumbres 1m", "ATLAS", or "JWST")
  50- 57 F8.3   d       Phase   [-147.31/200.03] Phase (G1)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: fig2b.dat
--------------------------------------------------------------------------------
   Bytes Format Units      Label  Explanations
--------------------------------------------------------------------------------
  1-   9 F9.3   d          MJD    [59547.8/59598.1] Modified Julian Date of
                                   observation (JD-2400000.5)
 11-  15 F5.3   d        E_MJD    Upper uncertainty on MJD
 17-  21 F5.3   d        e_MJD    Lower uncertainty on MJD
 23-  31 E9.3   W          Lbol   Pseudobolometric luminosity (1)
 33-  41 E9.3   W        E_Lbol   Upper uncertainty on Lbol
 43-  51 E9.3   W        e_Lbol   Lower uncertainty on Lbol
 53-  57 F5.3   kK         Tphot  Photospheric temperature (1)
 59-  63 F5.3   kK       E_Tphot  Upper uncertainty on Tphot
 65-  69 F5.3   kK       e_Tphot  Lower uncertainty on Tphot
 71-  76 F6.3   10+3Rsun   Rphot  Photospheric radius (1)
 78-  82 F5.3   10+3Rsun E_Rphot  Upper uncertainty on Rphot
 84-  88 F5.3   10+3Rsun e_Rphot  Lower uncertainty on Rphot
      90 I1     ---        Nfits  [2/6] Number of points used in fitting (1)
 92-  97 A6     ---        Filt   Filters used in fitting (1)
 99- 104 F6.3   d          Phase  [8.2/57] Phase (G1)
--------------------------------------------------------------------------------
Note (1): Lbol integrated from black-body SED fit using a Markov-chain Monte
    Carlo (MCMC) routine implemented in the Light Curve Fitting package,
    v0.7, Hosseinzadeh & Gomez (2020zndo...4312178H 2020zndo...4312178H).
--------------------------------------------------------------------------------
Global notes:
Note (G1): Phases are given with respect to the last prediscovery non-detection.
    we adopt the last prediscovery nondetection on 2021 November 21.352 UT
    as phase=0.
--------------------------------------------------------------------------------
History:
    From electronic version of the journal
(End)                    Prepared by [AAS], Emmanuelle Perret [CDS]  18-Nov-2024