Evidence of a Sub-Saturn around EPIC 211945201

Abhijit Chakraborty, Arpita Roy, Rishikesh Sharma, Suvrath Mahadevan, Priyanka Chaturvedi, Neelam J.S.S.V. Prasad, B. G. Anandarao

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

We report here strong evidence for a sub-Saturn around EPIC 211945201 and confirm its planetary nature. EPIC 211945201b was found to be a planetary candidate from K2 photometry in Campaigns 5 and 16, transiting a bright star (V mag = 10.15, G0 spectral type) in a 19.492 day orbit. However, the photometric data combined with false positive probability calculations using VESPA was not sufficient to confirm the planetary scenario. Here, we present high-resolution spectroscopic follow up of the target using the PARAS spectrograph (19 radial velocity observations) over a time baseline of 420 days. We conclusively rule out the possibility of an eclipsing binary system and confirm the 2σ detection of a sub-Saturn planet. The confirmed planet has a radius of 6.12 ±0.1 R , and a mass of . We also place an upper limit on the mass (within the 3σ confidence interval) at 42 M above the nominal value. This results in the Saturn-like density of . Based on the mass and radius, we provide a preliminary model-dependent estimate that the heavy element content is 60%-70% of the total mass. This detection is important as it adds to a sparse catalog of confirmed exoplanets with masses between 10 and 70 M and radii between 4 and 8 R , whose masses and radii are measured to a precision of 50% or better (only 23 including this work).

Original languageEnglish (US)
Article number3
JournalAstronomical Journal
Volume156
Issue number1
DOIs
StatePublished - Jul 2018

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Saturn
radii
Saturn (planet)
planet
heavy elements
extrasolar planets
radial velocity
confidence interval
spectrographs
catalogs
photometry
planets
confidence
intervals
orbits
stars
high resolution
estimates
approximation

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Chakraborty, A., Roy, A., Sharma, R., Mahadevan, S., Chaturvedi, P., Prasad, N. J. S. S. V., & Anandarao, B. G. (2018). Evidence of a Sub-Saturn around EPIC 211945201. Astronomical Journal, 156(1), [3]. https://doi.org/10.3847/1538-3881/aac436
Chakraborty, Abhijit ; Roy, Arpita ; Sharma, Rishikesh ; Mahadevan, Suvrath ; Chaturvedi, Priyanka ; Prasad, Neelam J.S.S.V. ; Anandarao, B. G. / Evidence of a Sub-Saturn around EPIC 211945201. In: Astronomical Journal. 2018 ; Vol. 156, No. 1.
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Chakraborty, A, Roy, A, Sharma, R, Mahadevan, S, Chaturvedi, P, Prasad, NJSSV & Anandarao, BG 2018, 'Evidence of a Sub-Saturn around EPIC 211945201', Astronomical Journal, vol. 156, no. 1, 3. https://doi.org/10.3847/1538-3881/aac436

Evidence of a Sub-Saturn around EPIC 211945201. / Chakraborty, Abhijit; Roy, Arpita; Sharma, Rishikesh; Mahadevan, Suvrath; Chaturvedi, Priyanka; Prasad, Neelam J.S.S.V.; Anandarao, B. G.

In: Astronomical Journal, Vol. 156, No. 1, 3, 07.2018.

Research output: Contribution to journalArticle

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Chakraborty A, Roy A, Sharma R, Mahadevan S, Chaturvedi P, Prasad NJSSV et al. Evidence of a Sub-Saturn around EPIC 211945201. Astronomical Journal. 2018 Jul;156(1). 3. https://doi.org/10.3847/1538-3881/aac436