J/ApJ/887/126 Follow-up obs. of the PSJ0147+4630 lens system (Goicoechea+, 2019)
Gravitational lens system PS J0147+4630 (Andromeda's Parachute): main lensing
galaxy and optical variability of the quasar images.
Goicoechea L.J., Shalyapin V.N.
<Astrophys. J., 887, 126-126 (2019)>
=2019ApJ...887..126G 2019ApJ...887..126G (SIMBAD/NED BibCode)
ADC_Keywords: Gravitational lensing; Spectra, optical; Photometry, SDSS
Keywords: Broad-absorption line quasar; Strong gravitational lensing
Quasar microlensing
Abstract:
Because follow-up observations of quadruple gravitational lens systems
are of extraordinary importance for astrophysics and cosmology, we
present single-epoch optical spectra and r-band light curves of
PS J0147+4630. This recently discovered system mainly consists of four
images ABCD of a background quasar around a foreground galaxy G that
acts as a gravitational lens. First, we use long-slit spectroscopic
data in the Gemini Observatory Archive and a multi-component fitting
to accurately resolve the spectra of A, D, and G. The spectral profile
of G resembles that of an early-type galaxy at a redshift of
0.678±0.001, which is about 20% higher than the previous estimate.
Additionally, the stellar velocity dispersion is measured to ∼5%
precision. Second, our early r-band monitoring with the Liverpool
Telescope leads to accurate light curves of the four quasar images.
Adopting time delays predicted by the lens model, the new lens
redshift, and a standard cosmology, we report the detection of
microlensing variations in C and D as large as ∼0.1mag on timescales
of a few hundred days. We also estimate an actual delay between A and
B of a few days (B is leading), which demonstrates the big potential
of optical monitoring campaigns of PS J0147+4630.
Description:
Lee (2018MNRAS.475.3086L 2018MNRAS.475.3086L) obtained Gemini Multi-Object Spectrograph
(GMOS) on the 8.1m Gemini North Telescope (GNT-GMOS) spectroscopic
data of PS J0147+4630 on 2017 September 2. We downloaded these
publicly available observations (Gemini Observatory Archive at
http://archive.gemini.edu/; Program ID: GN-2017B-FT-4) to reanalyze
them. See Section 2.
We monitored PS J0147+4630 with the 2.0m Liverpool Telescope (LT) from
2017 August to 2018 January and from 2018 July to 2019 February, i.e.,
during the first two visibility periods after its discovery. All
observations were made using the Sloan r-band filter on the IO:O
optical camera. See Section 3.
Objects:
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RA (ICRS) DE Designation(s)
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01 47 10.19 +46 30 43.8 PS J0147+4630 A = Gaia DR2 350937280928094336
01 47 10.30 +46 30 43.4 PS J0147+4630 B = Gaia DR2 350937280925970304
01 47 10.06 +46 30 43.7 PS J0147+4630 C = Gaia DR2 350937280925970432
01 47 10.16 +46 30 40.6 PS J0147+4630 D = Gaia DR2 350937280925971456
01 47 10.16 +46 30 41.5 PS J0147+4630 G = [BNR2017] J014710+463040 G
01 47 10.16 +46 30 41.5 PS J0147+4630 = [BNR2017] J014710+463040 source
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 48 3138 GNT-GMOS-B600 spectra of PS J0147+4630ADG
table2.dat 63 78 Photometry of the lens system PS J0147+4630
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See also:
J/MNRAS/371/703 : MILES library of empirical spectra (Sanchez-Blazquez+, 2006)
J/A+A/544/A62 : Spectra of 13 lensed quasars (Sluse+, 2012)
J/A+A/596/A77 : SDSS J1339+1310 spectra and light curves (Goicoechea+, 2016)
J/ApJ/836/14 : LCs & spectra of SDSSJ1515+1511 lens system (Shalyapin+, 2017)
J/MNRAS/465/4914 : R-band light curves of HE 0435-1223 (Bonvin+, 2017)
J/A+A/605/L8 : Spectra of lensed QSO PSOJ0147 (Lee, 2017)
J/A+A/616/A118 : Lensed QSOs LC & spectral monitoring (Gil-Merino+ 2018)
J/ApJ/836/14 : LCs & spectra of SDSSJ1515+1511 lens system (Shalyapin+, 2017)
J/ApJ/869/106 : SMARTS & Euler monitoring of WFI J2033-4723 (Morgan+, 2018)
J/A+A/646/A165 : SDSS J1339+1310 light curves and spectra (Shalyapin+, 2021)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 F8.3 0.1nm lambda [4402.9/7605.4] Observed wavelength
in Angstrom units
10- 16 F7.3 0.1nW/m3 FA [23/281] Flux of PS J0147+4630A,
in 10-17erg/cm2/s/Å units
18- 22 F5.3 0.1nW/m3 e_FA [1/7] Uncertainty in FA
24- 29 F6.3 0.1nW/m3 FD [1.5/27] Flux of PS J0147+4630D,
in 10-17erg/cm2/s/Å units
31- 35 F5.3 0.1nW/m3 e_FD [0.4/5.1] Uncertainty in FD
37- 42 F6.3 0.1nW/m3 FG [-0.4/1.9] Flux of PS J0147+4630G,
in 10-17erg/cm2/s/Å units
44- 48 F5.3 0.1nW/m3 e_FG [0.2/5] Uncertainty in FG (1)
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Note (1): The spectrum of G is not properly calibrated, since fluxes are
underestimated in a factor ∼5
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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- 10 A10 "Y/M/D" Date Civil date
12- 19 F8.3 d Epoch Epoch, Julian Date; JD-2450000.5
21- 24 F4.2 arcsec FWHM [0.7/2.4] Full-width at half-maximum
of the seeing disk
26- 28 I3 --- S/N [222/479] Signal-to-noise ratio
for the PSF star (1)
30- 35 F6.3 mag rmag-A [15.9/16] r-SDSS magnitude of PS J0147+4630A
37- 42 F6.3 mag rmag-B [16.1/16.3] r-SDSS magnitude of PS J0147+4630B
44- 49 F6.3 mag rmag-C [16.5/16.7] r-SDSS magnitude of PS J0147+4630C
51- 56 F6.3 mag rmag-D [18.2/18.4] r-SDSS magnitude of PS J0147+4630D
58- 63 F6.3 mag rmag-S [15.3/15.5] r-SDSS magnitude of the control star
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Note (1): Signal-to-noise ratio for the PSF star within a circle of radius FWHM.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 27-May-2021