J/AJ/161/108 R-band light curve of Qatar-1 (Su+, 2021)
Are there transit timing variations for the exoplanet Qatar-1b?
Su L.-H., Jiang I.-G., Sariya D.P., Lee C.-Y., Yeh L.-C., Mannaday V.K.,
Thakur P., Sahu D.K., Chand S., Shlyapnikov A.A., Moskvin V.V., Ignatov V.,
Mkrtichian D., Griv E.
<Astron. J., 161, 108 (2021)>
=2021AJ....161..108S 2021AJ....161..108S
ADC_Keywords: Exoplanets; Stars, high-velocity; Photometry, RI
Keywords: Exoplanet astronomy ; Transit photometry
Abstract:
Motivated by the unsettled conclusion on whether there are any transit
timing variations (TTVs) for the exoplanet Qatar-1b, 10 new transit
light curves are presented and a TTV analysis with a baseline of 1400
epochs is performed. Because the linear model provides a good fit with
a reduced chi-square of χred2=2.59 and the false-alarm
probabilities of the possible TTV frequencies are as large as 35%, our
results are consistent with a null-TTV model. Nevertheless, a new
ephemeris with a reference time of T0=2455647.63360±0.00008 (BJD)
and a period of P=1.4200236±0.0000001day is obtained. In addition,
the updated orbital semimajor axis and planetary radius in units of
stellar radius are provided, and the lower limit of the modified
stellar tidal quality factor is also determined.
Description:
Three telescopes at different sites were employed for our transit
observations.
One is the 60 inch telescope (P60) of Palomar Observatory located at
Palomar mountain in north San Diego County, California, USA. The mean
seeing quality of the images is about 1.9". The optical imager uses a
2048x2048pixel2 CCD array camera to image roughly 13x13arcmin2 of
sky.
Another telescope we used is the 0.5m telescope, MTM-500, which
belongs to the Crimean Astrophysical Observatory (CrAO) at Nauchny in
Crimea (longitude 34.1° east, latitude 44.32° north). The
camera mounted on MTM-500 is Apogee Alta U6 and the CCD array contains
1024x1024pixels2. The field of view is about 12x12 arcmin2, and
the image seeing is about 5" (0.71"/pixel plate scale).
In addition, we also observed with the 2m Himalayan Chandra Telescope
(HCT), located at Hanle, India. The observations of the Qatar-1 system
were taken in the Bessell R-filter by gathering 60s exposures using
the Himalaya Faint Object Spectrograph Camera (HFOSC), equipped with a
2048x4096pixels2 CCD with a pixel size of 15µm. The central
2048x2048 region of the CCD used for imaging covers a field of view of
10x10arcmin2 on the sky, with a scale of 0.296"/pixel.
Objects:
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RA (2000) DE Designation(s) (Period)
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20 13 31.62 +65 09 43.5 Qatar 1 = Qatar 1 (P=1.4200236d)
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 44 1572 The photometric light-curve data of this work
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See also:
J/A+A/529/A75 : Limb-darkening coefficients (Claret+, 2011)
J/AJ/142/84 : 10 new transit light curves of HAT-P-13b (Fulton+, 2011)
J/A+A/554/A28 : Qatar-1 differential light curve (Covino+, 2013)
J/AJ/145/68 : Five new transit light curves of TrES-3 (Jiang+, 2013)
J/A+A/555/A92 : Transit timing variations on Qatar-1 (von Essen+, 2013)
J/A+A/563/A41 : WASP-43 OSIRIS transmission spectroscopy (Murgas+, 2014)
J/A+A/577/A109 : Transit times of Qatar-1b (Maciejewski+, 2015)
J/AJ/151/17 : Eight transiting light curves of WASP-43b (Jiang+, 2016)
J/A+A/588/L6 : WASP-12 transit light curves (Maciejewski+ 2016)
J/AJ/154/4 : Times of transits and occultations of WASP-12b (Patra+, 2017)
J/AcA/68/371 : WASP and KELT planet transits (Maciejewski+, 2018)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 4 I4 yr Obs.Y [2014/2016] UT Year of the observation (1)
6- 8 A3 "month" Obs.M UT Month of the observation (1)
10- 11 I2 d Obs.D UT Day of the observation (1)
13- 26 F14.6 d BJD [2456912/2457635] Barycentric Julian Date; TDB
28- 35 F8.6 --- Flux [0.968/1.02] Relative Flux in R-band
37- 44 F8.6 --- e_Flux [0.0008/0.004] Uncertainty in RFlux
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Note (1): Note on epochs:
2014 Sep 12 is run 1 (epoch 891);
2014 Sep 22 is run 2 (epoch 898);
2014 Oct 02 is run 3 (epoch 905);
2014 Oct 10 is run 4 (epoch 911);
2014 Oct 29 is run 5 (epoch 924);
2015 Apr 03 is run 6 (epoch 1034);
2015 Apr 30 is run 7 (epoch 1053);
2016 Jun 30 is run 8 (epoch 1354);
2016 Jul 10 is run 9 (epoch 1361);
2016 Sep 02 is run 10 (epoch 1399).
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 16-Apr-2021