AAVSO 112th Annual Meeting, 2023

Arlo Landolt Lecturer:  Prof. Paula Szkody

Prof. Szkody uses a multiwavelength approach to study close binary stars with active mass transfer (Cataclysmic Variables). Her current research involves ultraviolet observations with the Hubble Space Telescope  as well as APO and ground-based optical facilities around the world.  She is currently finding the faintest, lowest mass transfer CVs  leading to insights into the nature of mass transfer and accretion onto magnetic and non-magnetic white dwarfs,  accretion disks and their X-ray-emitting boundary layers, stellar coronae, and the effects of irradiation on the upper atmospheres of late-type secondary stars.

Her work involves observations of all types of close binary systems involving mass transfer onto a white dwarf. This includes novae, dwarf novae, and novalikes which are all termed Cataclysmic Variables (CVs). The magnetism of the white dwarf determines if the mass flow from the low mass companion will be through an accretion disk, a curtain or a funnel onto the magnetic poles. The structure of the accretion flow as well as the underlying stars is determined from multiwavelength observations from X-ray through ultraviolet and optical to the infrared. Many of these objects are being discovered through ground-based surveys (SDSS, CRTS, iPTF) and followup takes place from space and ground to determine their specific types and how they fit into population models of close binary formation.

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Prof. Dipankar Maitra

An astrophysicist by training and an amateur astronomer at heart, Prof. Maitra works with students and collaborators around the world on understanding what happens near black holes and neutron stars. He is especially interested in understanding the coupling between accretion inflows and relativistic outflows near these objects. Lately he has been interested in optical polarization studies of the solar corona and other astronomical bodies as well. He earned his PhD from Yale University and did postdoctoral stints at the University of Amsterdam and the University of Michigan before joining the Physics & Astronomy faculty at Wheaton College (MA). He is constantly searching for better ways to involve students and amateur astronomers in astronomical research, and to make physics and astronomy classes more welcoming and inclusive. He uses telescopes in Wheaton’s on-campus observatory and other ground-based remote telescopes, as well as space-based optical, UV, and X-ray telescopes, for his teaching and research.

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Prof. Catherine Espaillat

Prof. Espaillat received her bachelor's degree from Columbia University in 2003 and earned a Ph.D. in Astrophysics from the University of Michigan in 2009.  She went on to the Harvard-Smithsonian Center for Astrophysics as an NSF Astronomy and Astrophysics Postdoctoral Fellow and she was later also awarded the NASA Carl Sagan Fellowship. Prof. Espaillet joined the Department of Astronomy at Boston University in 2013 where she is currently an Associate Professor.  She is a recipient of the Sloan Research Fellowship and the National Science Foundation’s CAREER award and is also a Fellow of the American Association for the Advancement of Science.

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Dr. Gail Schaefer

Dr. Schaefer is the Director of the CHARA Array of Georgia State University located at Mount Wilson Observatory in southern California. Gail earned her bachelor's degree from Binghamton University and PhD from Stony Brook University in New York. She did a postdoctoral position at the Space Telescope Science Institute in Baltimore, MD before moving to the CHARA Array in 2007. Her research interests include mapping the orbits of binary stars and understanding how young stars form and evolve over time. She leads a vibrant team that operates the CHARA Array and oversees an NSF funded program to offer open access time to the astronomical community.

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