Astrophysics Seminars

Mar
21
2024

Institute for Advanced Study Astrophysics Seminar

Black holes and revelations: unseen companions in stellar binaries
Kareem El-Badry
11:00am|Bloomberg Lecture Hall

The Milky Way contains of order 10^8 stellar-mass black holes (BHs). Yet, fewer than 100 BH candidates are known, and only about 20 are dynamically confirmed. Our view of the BH population has been shaped almost entirely by observations of X-ray...

Mar
14
2024

Institute for Advanced Study Astrophysics Seminar

The S(igma) 8 tension at the onset of stage-IV surveys
11:00am|Bloomberg Lecture Hall

In 1970, Allan Sandage famously described Cosmology as "A search for two numbers". In the half-century since that description of the field was penned, as Stage III cosmic surveys come to an end and Stage-IV surveys begin taking data, the field finds...

Mar
07
2024

Institute for Advanced Study Astrophysics Seminar

High energy neutrinos from Tidal Disruption Events.
Cecilia Lunardini
11:00am|Bloomberg Lecture Hall

Star-shredding supermassive black holes (Tidal Disruption Events, TDEs) are potential emitters of high energy hadrons and neutrinos. Several TDEs have been observed as coincident with neutrino events detected at the IceCube neutrino observatory. I...

Feb
29
2024

Institute for Advanced Study Astrophysics Seminar

New Insights into Strong Gravity from Accreting Black Holes
Prashant Kocherlakota
11:00am|Bloomberg Lecture Hall

Recent horizon-scale images of Messier 87* and Sagittarius A* have been used to demonstrate that their spacetimes are well-described by the Kerr metric. The latter is a solution to the vacuum Einstein equations of general relativity, and is used to...

Feb
22
2024

Institute for Advanced Study Astrophysics Seminar

Pulsar magnetospheres and their radiation
Sasha Phillipov
11:00am|Bloomberg Lecture Hall

In this talk, I will review recent progress in understanding the complex multi-scale plasma physics of neutron star magnetospheres through the lens of first-principles particle-in-cell simulations. I will highlight pair production discharges near...

Feb
15
2024

Institute for Advanced Study Astrophysics Seminar

Linear Inverse Problems, Quadratic Spectral Estimators & Spatiospectral Concentration to study Earth, Planets, and Space
11:00am|Bloomberg Lecture Hall

Many modern techniques to analyze global planetary signals, from satellite gravity and the geoid, to magnetic fields, to the making of seismological models, heavily rely on a global function basis - the spherical harmonics. When the available data...

Feb
08
2024

Institute for Advanced Study Astrophysics Seminar

Radio Astronomy from the Ends of the Earth
Jon Sievers
11:00am|Bloomberg Lecture Hall

Redshifted 21cm emission from neutral hydrogen is rapidly becoming one of our most powerful observables in cosmology. With it, we can study the evolution of dark energy at low/intermediate redshifts, the epoch of reionization, the first stars in the...

Feb
01
2024

Institute for Advanced Study Astrophysics Seminar

Circumbinary discs: Planet formation in a dynamically complex environment
Rebecca Martin
11:00am|Bloomberg Lecture Hall

Circumbinary discs around young stars have been observed to be misaligned to the binary orbital plane. A misaligned circumbinary gas disc evolves towards one of two states: alignment with the binary orbital plane or polar alignment where the disc is...

Dec
07
2023

Institute for Advanced Study Astrophysics Seminar

Exploring the Dynamics of Supercritical Accretion onto the Strongly Magnetized Neutron Stars
11:00am|Bloomberg Lecture Hall

Accretion-powered X-ray pulsars are neutron stars that accrete matter from a companion star in a binary system, which exhibit fascinating dynamics. The strong magnetic field of the neutron star guides material onto the magnetic poles, which are...