Astronomy and Astrophysics – Astrophysics – Solar and Stellar Astrophysics
Scientific paper
2010-09-27
Astrophys.J.723:L213-L217,2010
Astronomy and Astrophysics
Astrophysics
Solar and Stellar Astrophysics
5 pages, 2 figures, 1 table, ApJ Letters accepted
Scientific paper
10.1088/2041-8205/723/2/L213
The Mount Wilson Ca HK survey revealed magnetic activity variations in a large sample of solar-type stars with timescales ranging from 2.5 to 25 years. This broad range of cycle periods is thought to reflect differences in the rotational properties and the depths of the surface convection zones for stars with various masses and ages. In 2007 we initiated a long-term monitoring campaign of Ca II H and K emission for a sample of 57 southern solar-type stars to measure their magnetic activity cycles and their rotational properties when possible. We report the discovery of a 1.6-year magnetic activity cycle in the exoplanet host star iota Horologii, and we obtain an estimate of the rotation period that is consistent with Hyades membership. This is the shortest activity cycle so far measured for a solar-type star, and may be related to the short-timescale magnetic variations recently identified in the Sun and HD49933 from helio- and asteroseismic measurements. Future asteroseismic observations can be compared to those obtained near the magnetic minimum in 2006 to search for cycle-induced shifts in the oscillation frequencies. If such short activity cycles are common in F stars, then NASA's Kepler mission should observe their effects in many of its long-term asteroseismic targets.
Basu Sarbani
David Soderblom R.
Henry Todd J.
Judge Philip G.
Knoelker Michael
No associations
LandOfFree
Discovery of a 1.6-year Magnetic Activity Cycle in the Exoplanet Host Star iota Horologii does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Discovery of a 1.6-year Magnetic Activity Cycle in the Exoplanet Host Star iota Horologii, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Discovery of a 1.6-year Magnetic Activity Cycle in the Exoplanet Host Star iota Horologii will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-692591