English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We report improved masses, radii, and densities for four planets in twobright M-dwarf systems, K2-3 and GJ3470, derived from a combination of newradial velocity and transit observations. Supplementing K2 photometry withfollow-up Spitzer transit observations refined the transit ephemerides of K2-3b, c, and d by over a factor of 10. We analyze ground-based photometry from theEvryscope and Fairborn Observatory to determine the characteristic stellaractivity timescales for our Gaussian Process fit, including the stellarrotation period and activity region decay timescale. The stellar rotationsignals for both stars are evident in the radial velocity data and are includedin our fit using a Gaussian process trained on the photometry. We find themasses of K2-3 b, K2-3 c and GJ3470 b to be 6.48$^{+0.99}_{-0.93}$,2.14$^{+1.08}_{-1.04}$, and 12.58$^{+1.31}_{-1.28}$ M$_\oplus$ respectively.K2-3 d was not significantly detected and has a 3-$\sigma$ upper limit of 2.80M$_\oplus$. These two systems are training cases for future TESS systems; dueto the low planet densities ($\rho$ $<$ 3.7 g cm$^{-3}$) and bright host stars(K $<$ 9 mag), they are among the best candidates for transmission spectroscopyin order to characterize the atmospheric compositions of small planets.

the astronomical journal

Bright Opportunities for Atmospheric Characterization of Small Planets:  Masses and Radii of K2-3 b, c, d and GJ3470 b from Radial Velocity  Measurements and Spitzer Transits