J/MNRAS/449/1876 Photometric observations of SN PTF11iqb (Smith+, 2015)
PTF11iqb: cool supergiant mass-loss that bridges the gap between Type IIn
and normal supernovae.
Smith N., Mauerhan J.C., Cenko S.B., Kasliwal M.M., Silverman J.M.,
Filippenko A.V., Gal-Yam A., Clubb K.I., Graham M.L., Leonard D.C.,
Horst J.C., Williams G.G., Andrews J.E., Kulkarni S.R., Nugent P.,
Sullivan M., Maguire K., Xu D., Ben-Ami S.
<Mon. Not. R. Astron. Soc., 449, 1876-1896 (2015)>
=2015MNRAS.449.1876S 2015MNRAS.449.1876S (SIMBAD/NED BibCode)
ADC_Keywords: Supernovae ; Photometry, UBVRI ; Photometry, ultraviolet ;
Spectroscopy
Keywords: circumstellar matter - stars: evolution - supernovae: general -
supernovae: individual: PTF11iqb - stars: winds, outflows
Abstract:
The supernova (SN) PTF11iqb was initially classified as a Type IIn event
caught very early after explosion. It showed narrow Wolf-Rayet (WR)
spectral features on day 2 (as in SN 1998S and SN 2013cu), but the narrow
emission weakened quickly and the spectrum morphed to resemble Types II-L
and II-P. At late times, Hα exhibited a complex, multipeaked profile
reminiscent of SN 1998S. In terms of spectroscopic evolution, we find
that PTF11iqb was a near twin of SN 1998S, although with somewhat weaker
interaction with circumstellar material (CSM) at early times, and stronger
interaction at late times. We interpret the spectral changes as caused
by early interaction with asymmetric CSM that is quickly (by day 20)
enveloped by the expanding SN ejecta photosphere, but then revealed again
after the end of the plateau when the photosphere recedes. The light curve
can be matched with a simple model for CSM interaction (with a mass-loss
rate of roughly 10-4 M☉/yr) added to the light curve of a normal
SN II-P. The underlying plateau requires a progenitor with an extended
hydrogen envelope like a red supergiant at the moment of explosion,
consistent with the slow wind speed (<80 km/s) inferred from narrow
Hα emission. The cool supergiant progenitor is significant because
PTF11iqb showed WR features in its early spectrum - meaning that the
presence of such WR features does not necessarily indicate a WR-like
progenitor. Overall, PTF11iqb bridges SNe IIn with weaker pre-SN mass-loss
seen in SNe II-L and II-P, implying a continuum between these types.
Description:
We obtained R-band images of the PTF11iqb field including NGC 151 on
2011 July 22.9 with the Palomar 48-inch telescope (P48) equipped with
the refurbished CFHT12k camera (Rahmer et al. 2008SPIE.7014E..4YR).
Upon discovery of PTF11iqb, the field was automatically inserted into
the queue of the robotic Palomar 60-inch telescope (P60; Cenko et al.
2006PASP..118.1396C 2006PASP..118.1396C) for multifilter (r' and i') follow-up observations.
Images were processed using a custom pipeline, and subtracted from
reference images obtained in 2014 July using hotpants. Reported magnitudes
are on the AB system (Oke & Gunn 1983ApJ...266..713O 1983ApJ...266..713O).
All photometric data were collected using the Mount Laguna Observatory
(MLO; Smith & Nelson 1969PASP...81...74S 1969PASP...81...74S) 40-inch reflecting telescope,
which is equipped with a 2048x2048 pixel CCD camera (manufactured by
Fairchild Imaging Systems; CCD447) located at the f/7.6 Cassegrain focus,
providing a field of view of approximately 13.5 arcminx13.5 arcmin with
0.41 arcsec/pixel.
The Ultra-Violet Optical Telescope (UVOT; Roming et al.
2005SSRv..120...95R 2005SSRv..120...95R) onboard Swift observed PTF11iqb in the UVW1, UVM2,
and UVW2 filters beginning on 2011 July 24. We used a 3 arcsec diameter
aperture to extract flux from the transient, and subtracted
coincidence-loss-corrected count rates from underlying host emission
obtained from images in 2014 (e.g. Brown et al. 2009, J/AJ/137/4517).
We obtained spectra of PTF11iqb using a number of different facilities,
including the Bluechannel (BC) spectrograph on the 6.5-m Multiple Mirror
Telescope (MMT), the Multi-Object Double Spectrograph (MODS;
Byard & O'Brien 2000SPIE.4008..934B 2000SPIE.4008..934B) on the LBT, the Double Beam
Spectrograph (DBSP; Oke & Gunn 1982PASP...94..586O 1982PASP...94..586O) on the Palomar 200-inch
telescope (P200), the Intermediate dispersion Spectrograph and Imaging
System (ISIS5) on the 4.2-m William Herschel Telescope (WHT), GMOS on
Gemini South, the Kast spectrograph (Miller & Stone 1993) on the Lick 3-m
Shane reflector, the Low-Resolution Imaging Spectrometer (LRIS; Oke et al.
1995PASP..107..375O 1995PASP..107..375O) mounted on the 10-m Keck I telescope, and the Deep
Imaging Multi-Object Spectrograph (DEIMOS; Faber et al.
2003SPIE.4841.1657F 2003SPIE.4841.1657F) on Keck II.
Objects:
---------------------------------------------------
RA (ICRS) DE Designation(s)
---------------------------------------------------
00 34 04.84 -09 42 17.9 PTF11iqb = iPTF 13iqb
---------------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 20 53 P48 photometry
table2.dat 25 168 P60 r and i photometry of PTF11iqb
table3.dat 54 10 MLO magnitudes of local standards
table4.dat 78 12 MLO photometric observations of SN PTF11iqb
table5.dat 40 11 Swift/UVOT photometry of PTF11iqb
table6.dat 47 31 Spectroscopic observations of PTF11iqb
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See also:
J/AJ/137/4517 : UVOT light curves of supernovae (Brown P.J., 2009)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 7 F7.1 d MJD [55765.4/55854.3] Modified Julian Date
9- 14 F6.3 mag Rmag [15.147/16.862] Magnitude in Mould R filter
16- 20 F5.3 mag e_Rmag [0.025/0.076] Uncertainty in Rmag
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 9 F9.3 d MJD [55766.4/56330.2]? Modified Julian Date
11 A1 --- Filt [ri] Filter
13 A1 --- l_mag [<] Limit flag on mag
14- 19 F6.3 mag mag [15.217/22.33]? Magnitude in Filt
21- 25 F5.3 mag e_mag [0.003/1.151]? Uncertainty in mag
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Star [1/10] Star number
4- 9 F6.3 mag Bmag [11.928/17.893] Johnson B band magnitude
11- 15 F5.3 mag e_Bmag [0.04/0.065] Uncertainty in Bmag
17- 22 F6.3 mag Vmag [11.416/16.66] Johnson V band magnitude
24- 28 F5.3 mag e_Vmag [0.022/0.029] Uncertainty in Vmag
30- 35 F6.3 mag Rmag [11.093/15.858] Cousins R band magnitude
37- 41 F5.3 mag e_Rmag [0.033/0.042] Uncertainty in Rmag
43- 48 F6.3 mag Imag [10.778/15.192] Cousins I band magnitude
50- 54 F5.3 mag e_Imag [0.033/0.042] Uncertainty in Imag
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 10 A10 "date" Date UT date of observation
12- 17 F6.2 d Day [11.06/129.83] Days since first detection,
2011-07-22.9 UT (MJD 2455765.4)
19- 26 F8.2 d MJD [55776.4/55895.3] Modified Julian Date
28- 33 F6.3 mag Bmag [15.334/18.599]? Johnson B band magnitude (1)
35- 39 F5.3 mag e_Bmag [0.03/0.075]? Uncertainty in Bmag (1)
41- 46 F6.3 mag Vmag [15.26/18.485]? Johnson V band magnitude (1)
48- 52 F5.3 mag e_Vmag [0.023/0.097]? Uncertainty in Vmag (1)
54- 59 F6.3 mag Rmag [15.049/17.533]? Cousins R band magnitude (1)
61- 65 F5.3 mag e_Rmag [0.019/0.082]? Uncertainty in Rmag (1)
67- 72 F6.3 mag Imag [14.949/17.719]? Cousins I band magnitude (1)
74- 78 F5.3 mag e_Imag [0.014/0.041]? Uncertainty in Imag (1)
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Note (1): All photometric observations were made with the MLO 40-inch telescope.
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 7 F7.1 d MJD [55766.1/55807.1] Modified Julian Date
9- 13 F5.2 mag M2mag [14.87/19.54] Swift/UVOT UVM2 AB magnitude
15- 18 F4.2 mag e_M2mag [0.05/0.13] Uncertainty in M2mag
20- 24 F5.2 mag W1mag [14.91/18.8]? Swift/UVOT UVW1 AB magnitude
26- 29 F4.2 mag e_W1mag [0.05/0.1]? Uncertainty in W1mag
31- 35 F5.2 mag W2mag [14.93/19.87] Swift/UVOT UVW2 AB magnitude
37- 40 F4.2 mag e_W2mag [0.06/0.18]? Uncertainty in W2mag
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 11 A11 "date" Date Date of observation
13- 24 A12 --- Tel Telescope/Instrument used
26- 29 I4 d Day [2/1104] Days since first detection
31- 34 I4 0.1nm b_lambda [3200/5550]? Lower value of wavelength interval
(Å)
36- 40 I5 0.1nm B_lambda [7350/10300]? Upper value of wavelength interval
(Å)
41 A1 --- f_lambda [n] Flag indicating nondetection
43- 47 I5 K TBB [5600/25000]? Blackbody temperature
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History:
From electronic version of the journal
(End) Tiphaine Pouvreau [CDS] 03-Feb-2020