Othman BENOMAR
(NYUAD)
19/09/2017, 09:00
Orlagh Creevey
(Observatoire de la Cote d'Azur)
19/09/2017, 09:15
invited talk
In this talk I focus on the determination of ages of solar-like non evolved stars through asteroseismology. I will discuss the different methods that have been used in the literature for asteroseismic inference along with the assumptions that go into the modelling. I will also focus on the estimation of internal and external errors using the different methods. By comparing results from...
Jennifer van Saders
(Observatories of the Carnegie)
19/09/2017, 09:45
invited talk
Stellar rotation carries a wealth of information about stellar populations. In particular, the technique of gyro chronology was developed to utilize the spin-down of stars as a function of time as an indicator of stellar age. Gyrochronology has the potential to yield precise ages for large samples of stars, providing unprecedented chronological information for studies of the Milky Way and...
Marcel Agueros
(Columbia University)
19/09/2017, 10:45
talk
While we have known for 40 years of the existence of a relation between a solar-mass star's age, rotation, and magnetic activity, observational limitations have hampered the assembly of uniform samples of rotation and activity measurements for stars spanning a wide range of ages and masses. We are still far from being able to describe fully the evolution of either rotation or activity for...
Trent Dupuy
(Gemini Observatory)
19/09/2017, 11:00
talk
Brown dwarfs cool for their entire lifetimes and, when they are young, overlap in luminosity with low-mass stars. This creates the mass-age-luminosity degeneracy that usually muddles observations of the field population of such cool objects. However, it also presents an opportunity for precise age dating when mass and luminosity are measured. We have recently used Keck and CFHT to measure...
Rachel Booth
(Queen's University Belfast)
19/09/2017, 11:15
talk
Magnetic activity is crucial to the understanding of the potential habitability of exoplanets; the strong radiation emitted by a star can cause atmospheric mass loss from the exoplanet. Therefore, it is important to understand magnetic activity and its evolution with time. For solar and late-type stars it is known that they spin down over time due to magnetic braking, which has led to many...
Adam Burgasser
(UCSD)
19/09/2017, 11:30
talk
Age-dating ultracool dwarf stars and brown dwarfs is a critical challenge as these sources are increasingly important for searches of habitable exoplanets. Traditional diagnostics of rotation and magnetic activity are stymied by the decoupling of magnetic field lines from neutral photospheres; spectral diagnostics of surface gravity and lithium depletion are limited to young brown dwarfs (ages...
Thomas Ayres
(University of Colorado)
19/09/2017, 11:45
talk
The Alpha Centauri triple system (A: G2V; B: K1V; C: dM6) represents an important rung on the stellar age ladder. The two sunlike stars, A and B, have a resolved visual orbit (80 year period), and decades of radial velocity measurements (in part from recent planet hunting, spurred by "Breakthrough StarShot," which aims to send a swarm of laser-propelled nanobots to the system before the end...
Elisabeth Newton
(MIT)
19/09/2017, 12:00
talk
The ages of M dwarfs in the field of the galaxy are challenging to determine. Consequently, the evolution of rotation and magnetism at field ages is difficult to investigate observationally. Here, we present 200 new rotation period measurements for fully convective M dwarfs in the Southern hemisphere, about half of which are longer than 70 days. We make use of this sample and of our...
Katja Poppenhaeger
(Queen's University Belfast)
19/09/2017, 12:15
invited talk
The exoplanet field has made huge advances in planet characterization, atmosphere studies, and formation pathways. However, one crucial axis that is particularly hard to access when studying the evolution of exoplanets is the time axis. The physical means to get age information about exoplanet systems is through the age of the host star. A variety of methods has been employed to determine...
Ravi Kopparapu
(NASA Goddard)
19/09/2017, 15:45
invited talk
Host star has a crucial influence on the habitable zone and the habitability of a planet itself. Within our solar system, the evolution of the Sun over time has greatly affected the surface and atmospheric properties of rocky planets. A significant number of the host stars of exoplanets, particularly low-mass stars, are also active compared to the Sun. Determining accurate stellar ages and...
