Event Calendar

Title: Asteroseismology in the Gaia Era

Abstract: Stellar oscillations are powerful tools for understanding the structure and evolution of stars. With the advent of time domain space missions they can now be measured for large samples of evolved cool stars. The combination of this asteroseismic data, astrometry from Gaia, and large spectroscopic surveys is transforming our understanding of stellar populations and stellar physics. In this talk I review the current state of the art in red giant asteroseismology: both how well we can measure stellar properties using it and how it has changed our understanding of stellar populations and the theory of stellar structure and evolution. I will also discuss the powerful combination of asteroseismology and Gaia, providing two examples: testing the parallax zero point in Gaia with asteroseismology and testing asteroseismic scaling relations with Gaia.

Host: Cristobal Petrovich

Location: MP 1318A

Location: MP1318A

The schedule of speakers: https://tinyurl.com/cita-blackboard Location: MP 1318A

Location: MP 15th Floor Conf Room

Title: Irradiation-Reduced Mass Accretion by Neutron Stars in X-Ray Binaries

Abstract: Very precise timing measurements of binary millisecond pulsars (bMSPs) have allowed us to conclude that neutron stars (NSs) have a wide range of masses spanning from at least 1.17 to 2.0 Msun. However, we still do not know the upper limit to the mass that can be accreted by a neutron star and why the mass-transfer process that leads to its spin-up is so non-conservative. In this talk I will briefly describe some of the evolutionary pathways that lead to the formation of recycled pulsars and, in particular, bMSPs. I will show that X-ray irradiation feedback during the accretion phase of the formation of bMSPs can cause quasi-periodic episodes of highly non-conservative mass transfer that strongly attenuate mass accretion by the NSs. This results in the formation of bMSPs with greatly reduced masses than would have otherwise been expected from fully conservative mass transfer and leads to a much more robust agreement with observations. Most importantly, we demonstrate that our model has very little impact on the long-term, secular-average evolution of the low/intermediate-mass X-ray binary systems that are the progenitors of bMSPs.

Host: Dongzi Li (seminar host)

Location: MP 1318A

Weekly paper discussion focussing on pulsars, compact objects, and propagation effects. For a list of upcoming discussions, see: https://docs.google.com/spreadsheets/d/16TXacDDCk5FxMyw_842h5JHuq0h0RNhlWvp4li64edM/edit?usp=sharing If you would like to sign up for the presenter rota, email: simard@astro.utoronto.ca Location: CITA lounge

Open discussion of stars- and planets-related topics or more specialized discussion of dynamics-related papers on alternating weeks. See here for details. Location: MP 1318A

The schedule of speakers: https://tinyurl.com/cosmo-rota  
Location: 15th floor conference room

Location: MP1318A

The schedule of speakers: https://tinyurl.com/cita-blackboard Location: MP 1318A

Title: TBA

Abstract: TBA

Host: Simon Foreman

Location: MP1318A

Location: MP 15th Floor Conf Room

Weekly paper discussion focussing on pulsars, compact objects, and propagation effects. For a list of upcoming discussions, see: https://docs.google.com/spreadsheets/d/16TXacDDCk5FxMyw_842h5JHuq0h0RNhlWvp4li64edM/edit?usp=sharing If you would like to sign up for the presenter rota, email: simard@astro.utoronto.ca Location: CITA lounge

Location: MP1318A

The schedule of speakers: https://tinyurl.com/cosmo-rota  
Location: 15th floor conference room