Bibcode
Gaulme, P.; Rowe, J. F.; Bedding, T. R.; Benomar, O.; Corsaro, E.; Davies, G. R.; Hale, S. J.; Howe, R.; Garcia, R. A.; Huber, D.; Jiménez, A.; Mathur, S.; Mosser, B.; Appourchaux, T.; Boumier, P.; Jackiewicz, J.; Leibacher, J.; Schmider, F.-X.; Hammel, H. B.; Lissauer, J. J.; Marley, M. S.; Simon, A. A.; Chaplin, W. J.; Elsworth, Y.; Guzik, J. A.; Murphy, N.; Silva Aguirre, V.
Bibliographical reference
The Astrophysical Journal Letters, Volume 833, Issue 1, article id. L13, 7 pp. (2016).
Advertised on:
12
2016
Citations
11
Refereed citations
9
Description
Starting in 2014 December, Kepler K 2 observed Neptune continuously for
49 days at a 1 minute cadence. The goals consisted of studying its
atmospheric dynamics, detecting its global acoustic oscillations, and
those of the Sun, which we report on here. We present the first indirect
detection of solar oscillations in intensity measurements. Beyond the
remarkable technical performance, it indicates how Kepler would see a
star like the Sun. The result from the global asteroseismic approach,
which consists of measuring the oscillation frequency at maximum
amplitude ν max and the mean frequency separation between
mode overtones Δν, is surprising as the ν max
measured from Neptune photometry is larger than the accepted value.
Compared to the usual reference ν max,⊙ = 3100 μHz,
the asteroseismic scaling relations therefore make the solar mass and
radius appear larger by 13.8 ± 5.8% and 4.3 ± 1.9%,
respectively. The higher ν max is caused by a combination
of the value of ν max,⊙, being larger at the time of
observations than the usual reference from SOHO/VIRGO/SPM data (3160
± 10 μHz), and the noise level of the K 2 time series, being
10 times larger than VIRGO’s. The peak-bagging method provides
more consistent results: despite a low signal-to-noise ratio (S/N), we
model 10 overtones for degrees ℓ = 0, 1, 2. We compare the K 2 data
with simultaneous SOHO/VIRGO/SPM photometry and BiSON velocity
measurements. The individual frequencies, widths, and amplitudes mostly
match those from VIRGO and BiSON within 1σ, except for the few
peaks with the lowest S/N.