J/A+A/647/A93 AT 2020hat and AT 2020kog light curves (Pastorello+, 2021)
Forbidden hugs in pandemic times.
II. The luminous red nova variety: AT 2020hat and AT 2020kog.
Pastorello A., Valerin G., Fraser M., Elias-Rosa N., Valenti S.,
Reguitti A., Mazzali P.A., Amaro R.C., Andrews J.E., Dong Y., Jencson J.,
Lundquist M., Reichart D.E., Sand D.J., Wyatt S., Smartt S.J., Smith K.W.,
Srivastav S., Cai Y.-Z., Cappellaro E., Holmbo S., Fiore A., Jones D.,
Kankare E., Karamehmetoglu E., Lundqvist P., Morales-Garoffolo A.,
Reynolds T.M., Stritzinger M.D., Williams S.C., Chambers K.C.,
de Boer T.J.L., Huber M.E., Rest A., Wainscoat R.
<Astron. Astrophys. 647, A93 (2021)>
=2021A&A...647A..93P 2021A&A...647A..93P (SIMBAD/NED BibCode)
ADC_Keywords: Binaries, orbits; Mass loss; Photometry, UBV; Photometry, ugriz;
Photometry, infrared; Photometry, HST; Spectroscopy
Keywords: binaries: close - stars: winds, outflows -
stars: individual: AT 2020hat - stars: individual: AT 2020kog -
stars: individual: V1309 Sco - stars: individual: V838 Mon
Abstract:
We present the results of our monitoring campaigns of the luminous red
novae (LRNe) AT 2020hat in NGC 5068 and AT 2020kog in NGC 6106. The
two objects were imaged (and detected) before their discovery by
routine survey operations. They show a general trend of slow
luminosity rise lasting at least a few months. The subsequent major
LRN outbursts were extensively followed in photometry and
spectroscopy. The light curves present an initial short-duration peak,
followed by a redder plateau phase. AT 2020kog is a moderately
luminous event peaking at ∼7x1040erg/s, while AT 2020hat is almost
one order of magnitude fainter than AT 2020kog, although it is still
more luminous than V838 Mon. In analogy with other LRNe, the spectra
of AT 2020kog change significantly with time. They resemble those of
type IIn supernovae at early phases, then they become similar to those
of K-type stars during the plateau, and to M-type stars at very late
phases. In contrast, AT 2020hat already shows a redder continuum at
early epochs, and its spectrum shows the late appearance of molecular
bands. A moderate-resolution spectrum of AT 2020hat taken at +37d
after maximum shows a forest of narrow P Cygni lines of metals with
velocities of 180 km/s, along with an Halpha emission with a
full-width at half-maximum velocity of 250km/s. For AT 2020hat, a
robust constraint on its quiescent progenitor is provided by archival
images of the Hubble Space Telescope. The progenitor is clearly
detected as a mid-K type star, with an absolute magnitude of
M_F606W=-3.33±0.09mag and a colour of F606W-F814W=1.14±0.05mag,
which are inconsistent with the expectations from a massive star that
could later produce a core-collapse supernova. Although quite
peculiar, the two objects nicely match the progenitor versus light
curve absolute magnitude correlations discussed in the literature.
Description:
Table E1 contains the following broadband optical photometry of AT
2020hat (in the AB magnitude system), with associated errors: Sloan u,
g, r, i, z; Pan-STARRS w, ATLAS c, o.
Table E2 contains the following broadband optical photometry of AT
2020kog (in the AB magnitude system), with associated errors: Sloan u,
g, r, i, z; Pan-STARRS w.
Objects:
----------------------------------------------------------
RA (ICRS) DE Designation(s)
----------------------------------------------------------
13 19 01.93 -21 03 16.4 AT 2020hat = NAME ATLAS 20jxk
16 18 47.652 +07 25 16.86 AT 2020kog
----------------------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
tablee1.dat 134 721 Broadband Sloan u,g,r,i,z, Pan-STARRS w, and
ATLAS c,o photometry of AT 2020hat
(AB mag system), with errors
tablee2.dat 106 64 Broadband Sloan u,g,r,i,z and Pan-STARRS w
photometry of AT 2020kog (AB magn system),
with errors
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See also:
J/A+A/646/A119 : M31 luminous red nova AT 2019zhd photometry (Pastorello+ 2021)
Byte-by-byte Description of file: tablee1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 "YYYY-MM-DD" Date Date of the observation (yyyy-mm-dd)
12- 19 F8.2 --- MJD Modified Julian Date
21 A1 --- l_umag Limit flag on umag
22- 27 F6.3 mag umag ? Sloan u-band magnitude (AB)
29- 33 F5.3 mag e_umag ? u-band magnitude error
35 A1 --- l_gmag Limit flag on gmag
36- 41 F6.3 mag gmag ? Sloan g-band magnitude (AB)
43- 47 F5.3 mag e_gmag ? g-band magnitude error
49 A1 --- l_rmag Limit flag on rmag
50- 55 F6.3 mag rmag ? Sloan r-band magnitude (AB)
57- 61 F5.3 mag e_rmag ? r-band magnitude error
63 A1 --- l_imag Limit flag on imag
64- 69 F6.3 mag imag ? Sloan i-band magnitude (AB)
71- 75 F5.3 mag e_imag ? i-band magnitude error
77 A1 --- l_zmag Limit flag on zmag
78- 83 F6.3 mag zmag ? Sloan z-band magnitude (AB)
85- 89 F5.3 mag e_zmag ? z-band magnitude error
91 A1 --- l_wmag Limit flag on wmag
92- 97 F6.3 mag wmag ? Pan-STARRS w-band magnitude (AB)
99-103 F5.3 mag e_wmag ? w-band magnitude error
105 A1 --- l_cmag Limit flag on cmag
106-111 F6.3 mag cmag ? ATLAS cyan-band magnitude (AB)
113-117 F5.3 mag e_cmag ? cyan-band magnitude error
119 A1 --- l_omag Limit flag on omag
120-125 F6.3 mag omag ? ATLAS o-band magnitude (AB) 37
127-131 F5.3 mag e_omag ? o-band magnitude error
133-134 I2 --- Inst [1/14] Instrumental configuration code (1)
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Note (1): Instrumental configuration code as follows:
1 = 0.41m PROMPT-5 telescope (Cerro Tololo Inter-American Observatory, Chile)
2 = 0.41m PROMPT-MO-1 telescope (Meckering Observatory; Western Australia)
3 = 0.35m reflector telescope + KAF-1001E CCD (Itagaki Observatory;
Teppo-cho, Yamagata, Japan)
4 = 1.8m Pan-STARRS telescopes + GPC1/GPC2 cameras (Haleakala,
Hawaii Islands, USA)
5 = 0.5m ATLAS1 telescope (Haleakala, Hawaii Islands, USA)
6 = 0.5m ATLAS2 telescope (Mauna Loa; Hawaii Islands, USA)
7 = 2.56m Nordic Optical Telescope (NOT) + ALFOSC (La Palma,
Canary Islands, Spain)
8 = 2.0m Liverpool Telescope (LT) + IO:O (La Palma, Canary Islands, Spain)
9 = 1.22m Samuel Oschin Telescope, ZTF survey (Palomar Observatory;
California, USA)
10 = 3.58m Telescopio Nazionale Galileo (TNG) + LRS (La Palma,
Canary Islands, Spain)
11 = 10m Southern African Large Telescope (SALT) + SALTICAM
(South African Astron. Obs.; Sutherland, South Africa)
12 = 10.4m Gran Telescopio Canarias (GTC) + OSIRIS (La Palma,
Canary Islands, Spain)
13 = 1m Telescope (Dome C) + Sinistro CCD (South African Astronomical
Observatory; Sutherland, South Africa)
14 = 1m Telescope (Dome A) + Sinistro CCD (South African Astronomical
Observatory; Sutherland, South Africa)
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Byte-by-byte Description of file: tablee2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 A10 "YYYY-MM-DD" Date Date of the observation (yyyy-mm-dd)
12- 19 F8.2 --- MJD Modified Julian Date
21 A1 --- l_umag Limit flag on umag
22- 27 F6.3 mag umag ? Sloan u-band magnitude (AB)
29- 33 F5.3 mag e_umag ? u-band magnitude error
35 A1 --- l_gmag Limit flag on gmag
36- 41 F6.3 mag gmag ? Sloan g-band magnitude (AB)
43- 47 F5.3 mag e_gmag ? g-band magnitude error
49 A1 --- l_rmag Limit flag on rmag
50- 55 F6.3 mag rmag ? Sloan r-band magnitude (AB)
57- 61 F5.3 mag e_rmag ? r-band magnitude error
63 A1 --- l_imag Limit flag on imag
64- 69 F6.3 mag imag ? Sloan i-band magnitude (AB)
71- 75 F5.3 mag e_imag ? i-band magnitude error
77 A1 --- l_zmag Limit flag on zmag
78- 83 F6.3 mag zmag ? Sloan z-band magnitude (AB)
85- 89 F5.3 mag e_zmag ? z-band magnitude error
91 A1 --- l_wmag Limit flag on wmag
92- 97 F6.3 mag wmag ? Pan-STARRS w-band magnitude (AB)
99-103 F5.3 mag e_wmag ? w-band magnitude error
106 I1 --- Inst [1/8] Instrumental configuration code (1)
--------------------------------------------------------------------------------
Note (1): Instrumental configuration code as follows:
1 = 2.0m Liverpool Telescope (LT) + RATCam (La Palma, Canary Islands, Spain)
2 = 1.8m Pan-STARRS telescopes + GPC1/GPC2 cameras (Haleakala,
Hawaii Islands, USA)
3 = 2.0m Liverpool Telescope (LT) + IO:O (La Palma, Canary Islands, Spain)
4 = 1.82m Copernico Telescope + AFOSC (Cima Ekar, Asiago, Italy)
5 = 10.4m Gran Telescopio Canarias (GTC) + OSIRIS (La Palma,
Canary Islands, Spain)
6 = 1m Telescope (Dome C) + Sinistro CCD (South African Astronomical
Observatory; Sutherland, South Africa)
7 = 2.56m Nordic Optical Telescope (NOT) + ALFOSC (La Palma,
Canary Islands, Spain)
8 = 3.58m Telescopio Nazionale Galileo (TNG) + LRS (La Palma,
Canary Islands, Spain)
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Acknowledgements:
Andrea Pastorello, andrea.pastorello(at)inaf.it
References:
Pastorello et al., Paper I 2021A&A...646A.119P 2021A&A...646A.119P, Cat. J/A+A/646/A119
(End) Patricia Vannier [CDS] 15-Jan-2021