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arXiv · 0707.1908

The Transit Light Curve Project. VII. The Not-So-Bloated Exoplanet HAT-P-1b

Joshua N. Winn·Matthew J. Holman·Gaspar A. Bakos·Andras Pal·John Asher Johnson·Peter K. G. Williams·Avi Shporer·Tsevi Mazeh·Jose Fernandez·David W. Latham·Michael Gillon
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Abstract

We present photometry of the G0 star HAT-P-1 during six transits of its close-in giant planet, and we refine the estimates of the system parameters. Relative to Jupiter's properties, HAT-P-1b is 1.20 +/- 0.05 times larger and its surface gravity is 2.7 +/- 0.2 times weaker. Although it remains the case that HAT-P-1b is among the least dense of the known sample of transiting exoplanets, its properties are in accord with previously published models of strongly irradiated, coreless, solar-composition giant planets. The times of the transits have a typical accuracy of 1 min and do not depart significantly from a constant period.

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Joshua N. Winn, Matthew J. Holman, Gaspar A. Bakos, Andras Pal, John Asher Johnson, Peter K. G. Williams, Avi Shporer, Tsevi Mazeh, Jose Fernandez, David W. Latham, Michael Gillon. 2007-08-20. The Transit Light Curve Project. VII. The Not-So-Bloated Exoplanet HAT-P-1b. https://doi.org/10.1086/521599

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