J/A+A/628/A116 HAT-P-26 differential transit photometry (von Essen+, 2019)
Indications for transit-timing variations in the exo-Neptune HAT-P-26b.
von Essen C., Wedemeyer S., Sosa M.S., Hjorth M., Parkash V.,
Freudenthal J., Mallonn M., Miculan R.G., Zibecchi L., Cellone S.,
Torres A.F.
<Astron. Astrophys. 628, A116 (2019)>
=2019A&A...628A.116V 2019A&A...628A.116V (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Exoplanets ; Photometry
Keywords: instrumentation: photometers - techniques: photometric - time -
planets and satellites: fundamental parameters - stars: activity
Abstract:
From its discovery, the low density transiting Neptune HAT-P-26b
showed a 2.1 sigma detection drift in its spectroscopic data, while
photometric data showed a weak curvature in the timing residuals that
required further follow-up observations to be confirmed. To
investigate this suspected variability, we observed 11 primary
transits of HAT-P-26b between March, 2015 and July, 2018. For this, we
used the 2.15 meter Jorge Sahade Telescope placed in San Juan,
Argentina, and the 1.2 meter STELLA and the 2.5 meter Nordic Optical
Telescope, both located in the Canary Islands, Spain. To add upon
valuable information on the transmission spectrum of HAT-P-26b, we
focused our observations in the R-band only. To contrast the observed
timing variability with possible stellar activity, we carried out a
photometric follow-up of the host star along three years. We carried
out a global fit to the data and determined the individual mid-transit
times focusing specifically on the light curves that showed complete
transit coverage. Using bibliographic data corresponding to both
ground and space-based facilities, plus our new characterized
mid-transit times derived from parts-per-thousand precise photometry,
we observed indications of transit timing variations in the system,
with an amplitude of 4 minutes and a periodicity of 270 epochs. The
photometric and spectroscopic follow-up observations of this system
will be continued in order to rule out any aliasing effects caused by
poor sampling and the long-term periodicity.
Description:
11 differential photometry time series of primary transit events of
HAT-P-26b in the R band.
Objects:
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RA (2000) DE Designation(s)
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14 12 37.53 +04 03 36.1 HAT-P-26 = TYC 320-1027-1
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
hatp26.dat 117 5781 HAT-P-26 differential transit photometry
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See also:
J/A+A/628/A115 : WASP-12, CoRoT-1 and TrES-3 light curves (von Essen+, 2019)
Byte-by-byte Description of file: hatp26.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- Name [HATP26] Target of interest
10- 15 A6 --- Tel Telescope (CASLEO, NOT or STELLA)
19 A1 --- Filter [R] Photometric filter
23- 42 F20.12 d BJD Barycentric Julian Date (TDB)
44- 67 E24.19 --- FluxRaw Raw and normalized flux
69- 92 E24.19 --- e_FluxRaw Uncertainty of raw and normalized flux
94-117 E24.19 --- Fluxdet Detrended and normalized flux
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Acknowledgements:
Carolina von Essen, cessen(at)phys.au.dk
(End) Patricia Vannier [CDS] 12-Aug-2019