J/ApJ/834/107 Follow-up photometry of M101 OT2015-1 (Blagorodnova+, 2017)
Common envelope ejection for a luminous red nova in M101.
Blagorodnova N., Kotak R., Polshaw J., Kasliwal M.M., Cao Y., Cody A.M.,
Doran G.B., Elias-Rosa N., Fraser M., Fremling C., Gonzalez-Fernandez C.,
Harmanen J., Jencson J., Kankare E., Kudritzki R.-P., Kulkarni S.R.,
Magnier E., Manulis I., Masci F.J., Mattila S., Nugent P., Ochner P.,
Pastorello A., Reynolds T., Smith K., Sollerman J., Taddia F., Terreran G.,
Tomasella L., Turatto M., Vreeswijk P.M., Wozniak P., Zaggia S.
<Astrophys. J., 834, 107-107 (2017)>
=2017ApJ...834..107B 2017ApJ...834..107B (SIMBAD/NED BibCode)
ADC_Keywords: Photometry, UBVRI ; Photometry, SDSS ; Novae
Keywords: binaries: close; novae, cataclysmic variables;
stars: individual: (M101 OT2015-1, PSN J14021678+5426205);
stars: massive; stars: winds, outflows
Abstract:
We present the results of optical, near-infrared, and mid-infrared
observations of M101 OT2015-1 (PSN J14021678+5426205), a luminous red
transient in the Pinwheel galaxy (M101), spanning a total of 16 years.
The light curve showed two distinct peaks with absolute magnitudes
Mr≤-12.4 and Mr~-12, on 2014 November 11 and 2015 February 17,
respectively. The spectral energy distributions during the second
maximum show a cool outburst temperature of ∼3700K and low expansion
velocities (~-300km/s) for the HI, CaII, BaII, and KI lines. From
archival data spanning 15-8 years before the outburst, we find a
single source consistent with the optically discovered transient,
which we attribute to being the progenitor; it has properties
consistent with being an F-type yellow supergiant with
L∼8.7x104L☉, Teff∼7000K, and an estimated mass of
M1=18±1M☉. This star has likely just finished the H-burning
phase in the core, started expanding, and is now crossing the
Hertzsprung gap. Based on the combination of observed properties, we
argue that the progenitor is a binary system, with the more evolved
system overfilling the Roche lobe. Comparison with binary evolution
models suggests that the outburst was an extremely rare phenomenon,
likely associated with the ejection of the common envelope of a
massive star. The initial mass of the primary fills the gap between
the merger candidates V838 Mon (5-10M☉) and NGC 4490-OT
(30M☉).
Description:
The location of M101-OT2015-1 has been serendipitously imaged by
numerous telescopes and instruments over the last 15 years (from 2000
to 2015). Our best quality pre-discovery image (seeing of 0.55") is an
r-band exposure at -3625 days pre-peak from the Canada-France-Hawaii
Telescope (CFHT).
The historical optical data for M101-OT was retrieved from the CFHT
MegaPrime and CFHT12K/Mosaic, using single and combined exposures,
Pan-STARRS-1/GPC1 (PS1), Isaac Newton Telescope/Wide Field Camera
(INT/WFC), and Sloan Digital Sky Survey (SDSS) DR 10 (Ahn+ 2014, see
V/147). Unfortunately, there are no HST images covering the location
of the source.
Post-discovery optical magnitudes were obtained from the reported
followup astronomer's telegrams (ATels), Liverpool Telescope (LT), the
Nordic Optical Telescope (NOT), and the Palomar P48 and P60
telescopes. The infrared data were retrieved from CFHT/WIRCam,
UKIRT/WFCAM, and the Spitzer Infrared Array Camera in 3.6 and 4.5um as
part of the SPitzer InfraRed Intensive Transients Survey (SPIRITS)
(Kasliwal+, 2017ApJ...839...88K 2017ApJ...839...88K). Details of pre-discovery photometry
and post-discovery optical photometry may be found in the Appendices
Tables 1 and 2, respectively.
We obtained spectra of M101-OT using a range of facilities in 2015
Feb-Jul.
Objects:
--------------------------------------------------------
RA (ICRS) DE Designation(s)
--------------------------------------------------------
14 02 16.78 +54 26 20.5 M101 OT2015-1 = iPTF 13afz
--------------------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 147 55 Historic photometric measurements of M101-OT2015-1
table2.dat 126 26 Post-discovery photometric measurements
of M101-OT2015-1
table3.dat 54 97 iPTF follow-up data of M101-OT2015-1
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See also:
V/147 : The SDSS Photometric Catalogue, Release 12 (Alam+, 2015)
J/ApJ/682/1205 : Fast transients in the Fornax cluster (Rau+, 2008)
J/ApJ/705/1364 : MIR catalog of point sources in M33 (Thompson+, 2009)
J/ApJ/715/1094 : Census of self-obscured massive stars (Khan+, 2010)
J/ApJ/733/124 : Cepheids in M101 observed with HST (Shappee+, 2011)
J/ApJ/750/99 : The Pan-STARRS1 photometric system (Tonry+, 2012)
J/MNRAS/433/1312 : SN2009ip UBVRI, UVOT and JHK light curves (Fraser+, 2013)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 F7.1 d Phase Phase
9- 14 F6.1 d MJD Modified Julian Date; MJD-50000
16- 23 A8 --- Tel Telescope used
25- 29 F5.2 mag Umag [20.3/21.3]? U band magnitude
31- 34 F4.2 mag e_Umag [0.02/0.2]? Uncertainty in Umag
36- 40 F5.2 mag Bmag [18.8/22]? B band magnitude
42- 45 F4.2 mag e_Bmag [0.02/0.3]? Uncertainty in Bmag
47 A1 --- l_Vmag Limit flag on Vmag
48- 52 F5.2 mag Vmag [16.3/21.9]? V band magnitude
54- 57 F4.2 mag e_Vmag [0.02/0.4]? Uncertainty in Vmag
59- 63 F5.2 mag Rmag [16.7/21.2]? R band magnitude
65- 68 F4.2 mag e_Rmag [0.02/0.2]? Uncertainty in Rmag
70- 74 F5.2 mag umag [21.7/23.1]? SDSS u band magnitude
76- 79 F4.2 mag e_umag [0.1/0.5]? Uncertainty in umag
81- 85 F5.2 mag gmag [20.4/21.8]? SDSS g band magnitude
87- 90 F4.2 mag e_gmag [0.07/0.4]? Uncertainty in gmag
92- 96 F5.2 mag rmag [19.7/21.9]? SDSS r band magnitude
98-101 F4.2 mag e_rmag [0.04/0.3]? Uncertainty in rmag
103-107 F5.2 mag imag [19.7/21.5]? SDSS i band magnitude
109-112 F4.2 mag e_imag [0.06/0.5]? Uncertainty in imag
114-118 F5.2 mag zmag [19.8/22]? SDSS z band magnitude
120-123 F4.2 mag e_zmag [0.04/0.6]? Uncertainty in zmag
125-129 F5.2 mag ymag [19.5/20.4]? y band magnitude
131-134 F4.2 mag e_ymag [0.1/0.3]? Uncertainty in ymag
136-140 F5.2 mag unfmag [16.5/18]? Unfiltered magnitude
142-145 F4.2 mag e_unfmag [0.3]? Uncertainty in unfmag
147 A1 --- Ref Reference (1)
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Note (1): Reference as follows:
1 = Kelly et al. 2015ATel.7082....1K 2015ATel.7082....1K
2 = Gerke et al. 2015ATel.7069....1G 2015ATel.7069....1G
3 = Stanek et al. 2015ATel.7063....1S 2015ATel.7063....1S
4 = Margutti 2015ATel.7072....1M 2015ATel.7072....1M
5 = Goranskij et al. 2015ATel.7206....1G 2015ATel.7206....1G
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Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 F5.1 d Phase Phase
7- 12 F6.1 d MJD Modified Julian Date; MJD-50000
14- 21 A8 --- Tel Telescope used (LT, NOT, SAI-2.5m, SAI-6m or
Keck)
23- 27 F5.2 mag Umag [19.91]? U band magnitude
29- 32 F4.2 mag e_Umag [0.21]? Uncertainty in Umag
34- 38 F5.2 mag Bmag [19/22.5]? B band magnitude
40- 43 F4.2 mag e_Bmag [0/0.6]? Uncertainty in Bmag
45- 49 F5.2 mag Vmag [17.6/21]? V band magnitude
51- 54 F4.2 mag e_Vmag [0.02/0.3]? Uncertainty in Vmag
56 A1 --- l_Rmag Limit flag on Rmag
58- 62 F5.2 mag Rmag [16.8/23]? R band magnitude
64- 67 F4.2 mag e_Rmag [0.01/0.5]? Uncertainty in Rmag
69 A1 --- l_Imag Limit flag on Imag
71- 75 F5.2 mag Imag [16.3/25]? I band magnitude
77- 80 F4.2 mag e_Imag [0.03/0.2]? Uncertainty in Imag
82- 86 F5.2 mag gmag [19/22.2]? SDSS g band magnitude
88- 91 F4.2 mag e_gmag [0.06/0.4]? Uncertainty in gmag
93- 97 F5.2 mag rmag [17.7/23.5]? SDSS r band magnitude
99-102 F4.2 mag e_rmag [0.03/0.6]? Uncertainty in rmag
104-108 F5.2 mag imag [17.2/21.8]? SDSS i band magnitude
110-113 F4.2 mag e_imag [0.02/0.3]? Uncertainty in imag
115-119 F5.2 mag zmag [16.8/19.7]? SDSS z band magnitude
121-124 F4.2 mag e_zmag [0.01/0.07]? Uncertainty in zmag
126 A1 --- Ref Reference (1)
--------------------------------------------------------------------------------
Note (1): Reference as follows:
1 = Goranskij et al. 2015ATel.7206....1G 2015ATel.7206....1G
2 = Goranskij et al. 2016ATel.8599....1G 2016ATel.8599....1G
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Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 F7.1 d Phase Phase
9- 14 F6.1 d MJD Modified Julian Date; MJD-50000
16- 21 A6 --- Tel Telescope used (PTFP48 or PTFP60)
23- 27 F5.2 mag gmag [18.4/20.9]? The g band magnitude
29- 32 F4.2 mag e_gmag [0.01/0.2]? Uncertainty in gmag
34- 38 F5.2 mag rmag [16.6/20.5]? The r band magnitude
40- 43 F4.2 mag e_rmag [0.03/0.4]? Uncertainty in rmag
45- 49 F5.2 mag imag [16.6/20.6]? The i band magnitude
51- 54 F4.2 mag e_imag [0.01/0.2]? Uncertainty in imag
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 04-Jul-2017