J/ApJ/917/80 Opt-to-IR monitoring obs. of V1057 Cyg (Szabo+, 2021)
A study of the photometric and spectroscopic variations of the prototypical
FU Orionis-type star V1057 Cyg.
Szabo Z.M., Kospal A., Abraham P., Park S., Siwak M., Green J.D., Moor A.,
Pal A., Acosta-Pulido J.A., Lee J.-E., Cseh B., Csornyei G., Hanyecz O.,
Konyves-Toth R., Krezinger M., Kriskovics L., Ordasi A., Sarneczky K.,
Seli B., Szakats R., Szing A., Vida K.
<Astrophys. J., 917, 80 (2021)>
=2021ApJ...917...80S 2021ApJ...917...80S
ADC_Keywords: Stars, pre-main sequence; Photometry, UBVRI; Spectra, infrared
Keywords: FU Orionis stars ; Young stellar objects ; Circumstellar disks ;
Multi-color photometry ; Spectroscopy ; Photometry ; Light curves
Abstract:
Among the low-mass pre-main sequence stars, a small group called
FU Orionis-type objects (FUors) are notable for undergoing powerful
accretion outbursts. V1057 Cyg, a classical example of an FUor, went
into outburst around 1969-1970, after which it faded rapidly, making
it the fastest-fading FUor known. Around 1995, a more rapid increase
in fading occurred. Since that time, strong photometric modulations
have been present. We present nearly 10yr of source monitoring at
Piszkesteto Observatory, complemented with optical/NIR photometry and
spectroscopy from the Nordic Optical Telescope, Bohyunsan Optical
Astronomy Observatory, Transiting Exoplanet Survey Satellite, and
Stratospheric Observatory for Infrared Astronomy. Our light curves
show continuation of significant quasi-periodic variability in
brightness over the past decade. Our spectroscopic observations show
strong wind features, shell features, and forbidden emission lines.
All of these spectral lines vary with time. We also report the first
detection of [SII], [NII], and [OIII] lines in the star.
Description:
We performed the majority of our photometric observations in B, V,
RC, IC , g', r', and i' filters at the Piszkesteto Mountain
Station of Konkoly Observatory (Hungary) between 2005 and 2021. Three
telescopes with three slightly different optical systems were used:
the 1m Ritchey-Chretien-coude (RCC) telescope, the 60/90/180cm
Schmidt telescope and the Astro Systeme Austria AZ800 alt-azimuth
direct drive 80cm Ritchey-Chretien (RC80) telescope; see Section 2.1.
In addition to our national facilities, we occasionally used other
telescopes. On 2006 July 20 and 2012 October 13 we obtained B, V,
RJ, and IJ images of V1057 Cyg with the IAC80 telescope of the
Instituto de Astrofisica de Canarias located at Teide Observatory
(Canary Islands, Spain).
During 2019 August-September, in parallel with TESS, we additionally
observed V1057 Cyg at the Northern Skies Observatory (NSO). We used
the 0.4m telescope equipped with BVI filters.
We also observed V1057 Cyg with the 2.56m Nordic Optical Telescope
(NOT) at the Roque de los Muchachos Observatory, La Palma, in the
Canary Islands (Plan ID 61-414, PI: Zs. M. Szabo). For optical imaging
we used the Alhambra Faint Object Spectrograph and Camera (ALFOSC) on
2020 August 17. The Bessel BVR filter set was supplemented by an i
interference filter, which is similar to the SLOAN i', but with a
slightly longer effective wavelength of λeff=0.789um.
We obtained NIR images in the J, H, and Ks bands at six epochs between
2006 July 15 and 2012 October 13 using the 1.52m Telescopio Carlos
Sanchez (TCS) at the Teide Observatory.
We also used the NOTCam instrument on the NOT on 2020 August 29.
See Section 2.3.
We obtained a new optical spectrum of V1057 Cyg with the
high-resolution FIbre-fed Echelle Spectrograph (FIES) instrument on
the NOT on 2020 August 17. We used a fiber with a larger entrance
aperture of 2.5", which provided a spectral resolution R=25000,
covering the 370-900nm wavelength range.
V1057 Cyg was also observed with the Bohyunsan Optical Echelle
Spectrograph (BOES) installed on the 1.8m telescope at the Bohyunsan
Optical Astronomy Observatory (BOAO). It provides R=30000 in the
wavelength range ∼400-900nm. The first spectrum was obtained on
2012-September-11 and the last on 2018-December-18.
See Section 2.4.
On 2020 August 29, we used the NOTCam on the NOT to obtain new NIR
spectra of V1057 Cyg and Iot Cyg (A5 V) as our telluric standard star
in the JHKs bands. We used the low-resolution camera mode (R=2500).
See Section 2.5.
On 2018 September 6, we observed V1057 Cyg with the Stratospheric
Observatory for Infrared Astronomy (SOFIA) using
the Faint Object infraRed CAmera for the SOFIA Telescope (FORCAST).
We obtained mid-infrared imaging in a series of short exposures in
band F111 (10.6-11.6um) totaling ∼30s, a single exposure in F056
(5.6um) for 37s and F077 (7.5-8um) for 42s, and R∼100-200 spectra with
G063 (5-8um) and G227 (17-27um) (Plan ID 06_062, PI: J. D. Green).
See Section 2.6.
Objects:
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RA (ICRS) DE Designation(s)
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20 58 53.73 +44 15 28.3 V1057 Cyg = Gaia DR3 2162235662383047040
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 96 261 Optical and near-IR photometry of V1057 Cyg
fig14.dat 23 3060 The near-infrared J, H, and K spectrum of V1057 Cyg
observed with the Nordic Optical Telescope/NOTCam
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See also:
II/311 : WISE All-Sky Data Release (Cutri+ 2012)
II/328 : AllWISE Data Release (Cutri+ 2013)
I/347 : Distances to 1.33 billion stars in Gaia DR2 (Bailer-Jones+, 2018)
I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)
J/A+A/407/1157 : UVES sky atlas (Hanuschik+, 2003)
J/BaltA/15/483 : Vilnius photometry in LDN 935 (Laugalys+, 2006)
J/ApJS/193/25 : The NAN complex. II. MIPS observations (Rebull+, 2011)
J/MNRAS/434/38 : 25-years photometry of V1057 Cygni (Kopatskaya+, 2013)
J/AJ/147/140 : SED of 24 class I & class II FU Orionis stars (Gramajo+, 2014)
J/ApJ/792/L2 : C/2012 F6 (Lemmon) and C/2012 S1 (ISON) maps (Cordiner+, 2014)
J/ApJ/788/48 : X-ray through NIR photometry of NGC 2617 (Shappee+, 2014)
J/A+A/607/A39 : 7 FU Orionis-type stars CO spectral cubes (Feher+, 2017)
J/A+A/618/A79 : FU Orionis small-amplitude light variations (Siwak+, 2018)
J/ApJ/889/148 : V346 Nor IJHKs photometry & IR spectra (Kospal+, 2020)
J/ApJ/899/128 : Members of NGC 7000/IC 5070 Complex (Kuhn+, 2020)
J/A+A/643/A29 : Z CMa NW emission lines (Sicilia-Aguilar+, 2020)
J/A+A/644/A135 : V646 Pup TESS & ground photometry and spectrum (Siwak+, 2020)
Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 4 I4 yr Obs.Y [2005/2021] Year of the observation
6- 7 I2 "month" Obs.M Month of the observation
9- 10 I2 d Obs.D Day of the observation
12- 19 F8.2 d MJD [53672.75/59343.04] Modified Julian Date
21- 25 F5.2 mag Bmag [14.07/14.99]? Apparent Johnson B band magnitude
27- 31 F5.2 mag Vmag [12.3/12.97]? Apparent Johnson V band magnitude
33- 37 F5.2 mag gpmag [13.49/13.82]? Apparent Sloan g' band magnitude
39- 43 F5.2 mag RCmag [11.26/11.81]? Apparent Cousins R band magnitude
45- 49 F5.2 mag ICmag [10.19/10.67]? Apparent Cousins I band magnitude
51- 55 F5.2 mag RJmag [11.39/11.58]? Apparent Johnson R band magnitude
57- 61 F5.2 mag IJmag [10.42/10.59]? Apparent Johnson I band magnitude
63- 67 F5.2 mag rpmag [11.7/11.96]? Apparent Sloan r' band magnitude
69- 73 F5.2 mag ipmag [7.34/11.19]? Apparent Sloan i' band magnitude
75- 78 F4.2 mag Jmag [8.03/8.52]? Apparent 2MASS J band magnitude
80- 83 F4.2 mag Hmag [7.19/7.31]? Apparent 2MASS H band magnitude
85- 88 F4.2 mag Ksmag [6.13/7.29]? Apparent 2MASS Ks band magnitude
90- 96 A7 --- Inst Instrument used (1)
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Note (1): Instrument as follows:
Schmidt = The 60/90/180cm Schmidt telescope at the Piszkesteto Mountain
Station of Konkoly Observatory (180 occurrences)
RC80 = the Astro Systeme Austria AZ800 alt-azimuth direct drive 80cm
Ritchey-Chretien telescope (66 occurrences)
TCS = the 1.52m Telescopio Carlos Sanchez at the Teide Observatory
(6 occurrences)
RCC = the 1m Ritchey-Chretien-coude telescope at the Piszkesteto Mountain
Station of Konkoly Observatory (5 occurrences)
IAC80 = the IAC80 telescope of the Instituto de Astrofisica de Canarias
located at Teide Observatory (Canary Islands, Spain; 2 occurrences)
NOT = the 2.56m Nordic Optical Telescope (NOT) at the Roque de
los Muchachos Observatory, La Palma, in the Canary Islands
(2 occurrences)
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Byte-by-byte Description of file: fig14.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- Band IR band
4- 12 F9.7 um lambda [1.18/2.36] Wavelength
14- 23 E10.3 cW/m2/nm Flux [9.2e-14/1.91e-13]?=-9.999 Flux;
in erg/s/cm2/Å units
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 11-Jan-2023