J/MNRAS/449/1941  Optical/NIR photometry of OGLE-2012-SN-006 (Pastorello+, 2015)
Massive stars exploding in a He-rich circumstellar medium -
V. Observations of the slow-evolving SN Ibn OGLE-2012-SN-006.
    Pastorello A., Wyrzykowski L., Valenti S., Prieto J.L., Kozlowski S.,
    Udalski A., Elias-Rosa N., Morales-Garoffolo A., Anderson J.P., Benetti S.,
    Bersten M., Botticella M.T., Cappellaro E., Fasano G., Fraser M.,
    Gal-Yam A., Gillone M., Graham M.L., Greiner J., Hachinger S., Howell D.A.,
    Inserra C., Parrent J., Rau A., Schulze S., Smartt S.J., Smith K.W.,
    Turatto M., Yaron O., Young D.R., Kubiak M., Szymanski M.K.,
    Pietrzynski G., Soszynski I., Ulaczyk K., Poleski R., Pietrukowicz P.,
    Skowron J., Mroz P.
   <Mon. Not. R. Astron. Soc., 449, 1941-1953 (2015)>
   =2015MNRAS.449.1941P 2015MNRAS.449.1941P    (SIMBAD/NED BibCode)
ADC_Keywords: Supernovae ; Photometry, UBVRI ; Photometry, infrared 
Keywords: supernovae: general - supernovae: individual: OGLE-2012-SN-006 -
          supernovae: individual: SN 2006jc - supernovae: individual: SN 2010al
Abstract:
    We present optical observations of the peculiar Type Ibn supernova
    (SN Ibn) OGLE-2012-SN-006, discovered and monitored by the Optical
    Gravitational Lensing Experiment-IV survey, and spectroscopically
    followed by Public ESO Spectroscopic Survey of Transient Objects
    (PESSTO) at late phases. Stringent pre-discovery limits constrain the
    explosion epoch with fair precision to JD=2456203.8±4.0. The rise
    time to the I-band light-curve maximum is about two weeks. The object
    reaches the peak absolute magnitude MI=-19.65±0.19 on
    JD=2456218.1±1.8. After maximum, the light curve declines for
    about 25 d with a rate of 4 mag (100 d)-1. The symmetric I-band peak
    resembles that of canonical Type Ib/c supernovae (SNe), whereas SNe Ibn
    usually exhibit asymmetric and narrower early-time light curves. Since
    25 d past maximum, the light curve flattens with a decline rate slower
    than that of the 56Co-56Fe decay, although at very late phases it
    steepens to approach that rate. However, other observables suggest
    that the match with the 56Co decay rate is a mere coincidence, and the
    radioactive decay is not the main mechanism powering the light curve
    of OGLE-2012-SN-006. An early-time spectrum is dominated by a blue
    continuum, with only a marginal evidence for the presence of HeI lines
    marking this SN type. This spectrum shows broad absorptions bluewards
    than 5000 Å, likely OII lines, which are similar to spectral
    features observed in superluminous SNe at early epochs. The object has
    been spectroscopically monitored by PESSTO from 90 to 180 d after
    peak, and these spectra show the typical features observed in a number
    of SN 2006jc-like events, including a blue spectral energy distribution
    and prominent and narrow (νFWHM∼1900 km/s) HeI emission lines.
    This suggests that the ejecta are interacting with He-rich circumstellar
    material. The detection of broad (104 km/s) OI and CaII features
    likely produced in the SN ejecta (including the [OI]
    λλ6300,6364 doublet in the latest spectra) lends support
    to the interpretation of OGLE-2012-SN-006 as a core-collapse event.
Description:
    Photometric measurements in the optical and NIR bands were obtained
    through the PSF-fitting technique. A template PSF was built using
    stars in the SN field. With this PSF model along with a low-order
    polynomial surface, we finally performed a fit to the SN and the
    underlying background. OGLE-IV photometry was obtained using the
    difference imaging analysis, which is a template subtraction method
    adapted to the OGLE data and detailed in Wyrzykowski et al. 2014,
    J/AcA/64/197 (see also Wozniak 2000, J/AcA/50/421).
Objects:
 ---------------------------------------------------------------
     RA   (ICRS)    DE        Designation(s)
 ---------------------------------------------------------------
  03 33 34.79   -74 23 40.1   OGLE-2012-SN-006 = OGLE 2012-SN-6
 ---------------------------------------------------------------
File Summary:
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 FileName      Lrecl  Records   Explanations
--------------------------------------------------------------------------------
ReadMe            80        .   This file
tablea1.dat       77      123   Optical photometry of OGLE-2012-SN-006
tablea2.dat       54        7   NIR photometry of OGLE-2012-SN-006
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See also:
 J/AcA/50/421  : OGLE-II DIA BUL_SC1 field (Wozniak, 2000)
 J/AcA/64/197  : OGLE-IV 2012-2014 transients (Wyrzykowski+, 2014)
 J/A+A/602/A93 : SN Type Ibn OGLE-2014-SN-131 lightcurves
                                                         (Karamehmetoglu+, 2017)
Byte-by-byte Description of file: tablea1.dat
--------------------------------------------------------------------------------
   Bytes Format Units    Label   Explanations
--------------------------------------------------------------------------------
   1- 10  A10   "date"   Date    Observation date
  12- 19  F8.2  d        JD      Julian Date (JD-2400000)
  21- 25  F5.2  mag      Umag    ? U-band magnitude
  27- 30  F4.2  mag    e_Umag    ? Uncertainty in Umag
  32- 36  F5.2  mag      Bmag    ? B-band magnitude
  38- 41  F4.2  mag    e_Bmag    ? Uncertainty in Bmag
  43- 47  F5.2  mag      Vmag    ? V-band magnitude
  49- 52  F4.2  mag    e_Vmag    ? Uncertainty in Vmag
  54- 58  F5.2  mag      Rmag    ? R-band magnitude
  60- 63  F4.2  mag    e_Rmag    ? Uncertainty in Rmag
      65  A1    ---    l_Imag    [>] Limit flag on Imag
  66- 70  F5.2  mag      Imag    ? I-band magnitude
  72- 75  F4.2  mag    e_Imag    ? Uncertainty in Imag
      77  I1    ---      Inst    [1/6] Instrument identification (G1)
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Byte-by-byte Description of file: tablea2.dat
--------------------------------------------------------------------------------
   Bytes Format Units    Label   Explanations
--------------------------------------------------------------------------------
   1- 10  A10   "date"   Date    Observation date
  12- 19  F8.2  d        JD      Julian Date (JD-2400000)
  21- 25  F5.2  mag      Jmag    J-band magnitude
  27- 30  F4.2  mag    e_Jmag    Uncertainty in Jmag
  32- 36  F5.2  mag      Hmag    ? H-band magnitude
  38- 41  F4.2  mag    e_Hmag    ? Uncertainty in Hmag
  43- 47  F5.2  mag      Kmag    ? K-band magnitude
  49- 52  F4.2  mag    e_Kmag    ? Uncertainty in Kmag
      54  I1    ---      Inst    [1/6] Instrument identification (G1)
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Global notes:
Note (G1): Instrument as follows:
  1 = 1.3-m Warsaw University Telescope + OGLE-IV mosaic camera (Las Campanas
      Observatory);
  2 = 2.2-m MPI/ESO Telescope + GROND (ESO-La Silla Observatory);
  3 = 3.58-m New Technology Telescope + EFOSC2 (ESO-LaSilla Observatory);
  4 = LCOGT 1.0m-05 telescope + SBIG STX-16083 with Kodak KAF-16803 FI (Cerro
      Tololo InterAmerican Observatory);
  5 = LCOGT 1.0m-09 telescope + SBIG STX-16083 with Kodak KAF-16803 FI (Cerro
      Tololo Inter-American Observatory);
  6 = 3.58-m New Technology Telescope + SOFI (ESO-La Silla Observatory).
--------------------------------------------------------------------------------
History:
    From electronic version of the journal
References:
 Pastorello et al.   Paper I.      2008MNRAS.389..113P 2008MNRAS.389..113P
 Pastorello et al.   Paper II.     2008MNRAS.389..131P 2008MNRAS.389..131P
 Mattila et al.      Paper III.    2008MNRAS.389..141M 2008MNRAS.389..141M
 Pastorello et al.   Paper IV.     2015MNRAS.449.1921P 2015MNRAS.449.1921P, Cat. J/MNRAS/449/1921
 Pastorello et al.   Paper VI.     2015MNRAS.449.1954P 2015MNRAS.449.1954P
 Pastorello et al.   Paper VII.    2015MNRAS.453.3649P 2015MNRAS.453.3649P
 Pastorello et al.   Paper VIII.   2015MNRAS.454.4293P 2015MNRAS.454.4293P
 Pastorello et al.   Paper IX.     2016MNRAS.456..853P 2016MNRAS.456..853P
(End)                       Tiphaine Pouvreau [CDS]                  06-Dec-2017