中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
The GTC exoplanet transit spectroscopy survey VIII. Flat transmission spectrum for the warm gas giant WASP-80b

文献类型:期刊论文

作者Parviainen, H.1,2,3; Palle, E.1,2; Chen, G.1,2,4; Nortmann, L.1,2; Murgas, F.1,2; Nowak, G.1,2; Aigrain, S.3; Booth, A.5; Abazorius, M.3; Iro, N.6
刊名ASTRONOMY & ASTROPHYSICS
出版日期2018-01-05
卷号609页码:16
关键词planets and satellites: individual: WASP-80b planets and satellites: atmospheres stars: individual: WASP-80 techniques: photometric techniques: spectroscopic methods: statistical
ISSN号1432-0746
DOI10.1051/0004-6361/201731113
通讯作者Parviainen, H.(hannu@iac.es)
英文摘要Aims. We set out to study the atmosphere of WASP-80b, a warm inflated gas giant with an equilibrium temperature of similar to 800 K, using ground-based transmission spectroscopy covering the spectral range from 520 to 910 nm. The observations allow us to probe the existence and abundance of K and Na in WASP-80b's atmosphere, existence of high-altitude clouds, and Rayleigh-scattering in the blue end of the spectrum. Methods. We observed two spectroscopic time series of WASP-80b transits with the OSIRIS spectrograph installed in the Gran Telescopio Canarias (GTC), and use the observations to estimate the planet's transmission spectrum between 520 nm and 910 nm in 20 nm-wide passbands, and around the K I and Na I resonance doublets in 6 nm-wide passbands. We jointly model three previously published broadband datasets consisting of 27 light curves, prior to a transmission spectroscopy analysis in order to obtain improved estimates of the planet's orbital parameters, average radius ratio, and stellar density. The parameter posteriors from the broadband analysis are used to set informative priors on the transmission spectroscopy analysis. The final transmission spectroscopy analyses are carried out jointly for the two nights using a divide-by-white approach to remove the common-mode systematics, and Gaussian processes to model the residual wavelength-dependent systematics. Results. We recover a flat transmission spectrum with no evidence of Rayleigh scattering or K I or Na I absorption, and obtain an improved system characterisation as a by-product of the broadband- and GTC-dataset modelling. The transmission spectra estimated separately from the two observing runs are consistent with each other, as are the transmission spectra estimated using either a parametric or nonparametric systematics model. The flat transmission spectrum favours an atmosphere model with high-altitude clouds over cloud-free models with stellar or sub-stellar metallicities. Conclusions. Our results disagree with the recently published discovery of strong K I absorption in WASP-80b's atmosphere based on ground-based transmission spectroscopy with FORS2 at VLT.
WOS关键词COOL DWARF ; GJ 1214B ; ATMOSPHERE ; EFFICIENT ; SYSTEM
WOS研究方向Astronomy & Astrophysics
语种英语
WOS记录号WOS:000419994200001
出版者EDP SCIENCES S A
源URL[http://libir.pmo.ac.cn/handle/332002/22142]  
专题中国科学院紫金山天文台
通讯作者Parviainen, H.
作者单位1.IAC, Tenerife 38200, Spain
2.ULL, Dept Astrofis, Tenerife 38206, Spain
3.Univ Oxford, Subdept Astrophys, Dept Phys, Oxford OX1 3RH, England
4.Chinese Acad Sci, Purple Mt Observ, Key Lab Planetary Sci, Nanjing 210008, Jiangsu, Peoples R China
5.Univ Leeds, Sch Phys & Astron, Leeds LS2 9JT, W Yorkshire, England
6.Univ Hamburg, Theoret Meteorol Grp, Klimacampus,Grindelberg 5, D-20144 Hamburg, Germany
推荐引用方式
GB/T 7714
Parviainen, H.,Palle, E.,Chen, G.,et al. The GTC exoplanet transit spectroscopy survey VIII. Flat transmission spectrum for the warm gas giant WASP-80b[J]. ASTRONOMY & ASTROPHYSICS,2018,609:16.
APA Parviainen, H..,Palle, E..,Chen, G..,Nortmann, L..,Murgas, F..,...&Iro, N..(2018).The GTC exoplanet transit spectroscopy survey VIII. Flat transmission spectrum for the warm gas giant WASP-80b.ASTRONOMY & ASTROPHYSICS,609,16.
MLA Parviainen, H.,et al."The GTC exoplanet transit spectroscopy survey VIII. Flat transmission spectrum for the warm gas giant WASP-80b".ASTRONOMY & ASTROPHYSICS 609(2018):16.

入库方式: OAI收割

来源:紫金山天文台

浏览0
下载0
收藏0
其他版本

除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。