A much lower density for the transiting extrasolar planet WASP-7
| Autor: | Southworth, John, Dominik, M., Jorgensen, U. G., Rahvar, S., Snodgrass, C., Alsubai, K., Bozza, V., Browne, P., Burgdorf, M., Novati, S. Calchi, Dodds, P., Dreizler, S., Finet, F., Gerner, T., Hardis, S., Harpsoe, K., Hellier, C., Hinse, T. C., Hundertmark, M., Kains, N., Kerins, E., Liebig, C., Mancini, L., Mathiasen, M., Penny, M. T., Proft, S., Ricci, D., Sahu, K., Scarpetta, G., Schafer, S., Schonebeck, F., Surdej, J. |
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| Rok vydání: | 2010 |
| Předmět: | |
| Druh dokumentu: | Working Paper |
| DOI: | 10.1051/0004-6361/201016183 |
| Popis: | We present the first high-precision photometry of the transiting extrasolar planetary system WASP-7, obtained using telescope defocussing techniques and reaching a scatter of 0.68 mmag per point. We find that the transit depth is greater and that the host star is more evolved than previously thought. The planet has a significantly larger radius (1.330 +/- 0.093 Rjup versus 0.915 +0.046 -0.040 Rjup) and much lower density (0.41 +/- 0.10 rhojup versus 1.26 +0.25 -0.21 rhojup) and surface gravity (13.4 +/- 2.6 m/s2 versus 26.4 +4.4 -4.0 m/s2) than previous measurements showed. Based on the revised properties it is no longer an outlier in planetary mass--radius and period--gravity diagrams. We also obtain a more precise transit ephemeris for the WASP-7 system. Comment: Accepted for publication as a Research Note in A&A. 5 pages, 4 tables, 3 figures |
| Databáze: | arXiv |
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