Seminar Schedule

Astrophysics Seminar meets in room 309 VAN on Tuesdays from 12:30 am - 1:30 pm. 

The format is either Astrophysics Journal club or a research presentation.  Journal club papers for the current week are listed  at VoxCharta (select University of Iowa). Everyone is encouraged to briefly review the selected papers before seminar. Moderators are expected to provide cookies.

Date Speaker Title
Jan 23 Prof. Ken Gayley, UI Analyzing the Cause of Death in the Coronal Graveyard
Jan 30 John Haiducek, Univ. Michigan Can global MHD be used to predict substorms?
Feb 6 Dr. Rachael Filwett, U.Texas (San Antonio) Acceleration of Suprathermal Ions in Corotating Interaction Regions
Feb 8
(note:Thur)
Dr. Cormac Purcell, Macquerie Univ. Adventures on the radio frontier: preparing for the next generation of big radio surveys
Feb 13 Dr. Kristine Sigsbee, U. Iowa Statistical study of EMIC Waves as observed by the Van Allen Probes
Feb 20 Dr. William Kurth, U. Iowa Plasma Waves associated with Broadband Electron Auroral Precipitation at Jupiter
Feb 27 Dr. Anna Zajczyk, U. Iowa
Mar 6 Ali Sulaiman, U. Iowa
Mar 13 SPRING BREAK
Mar 20 Yue Shen (UIUC), Fran Bagenal, U. Colorado
Mar 27 Dr. Sadie Elliott, U. Iowa
Apr 3 Prof. Allison Jaynes, U.Iowa
Apr 10 Dr. Suranga Ruhunusiri
Apr 17 Dr. Justin Crepp
Apr 24 Mr. Dylan Pare, U. Iowa
May 1 TBA


Abstracts

  K. Gayley: Analyzing the Cause of Death in the Coronal Graveyard

Abstract: As stars evolve, two things normally occur: they greatly expand, and they lose their coronae. Although the causes of the former are well understood, the latter has eluded a simple explanation for half a century. Here a simple approach is offered to explain the "coronal graveyard" in terms of a natural increase in the kinetic energy per particle for a mechanically heated atmosphere. In the process, a potential explanation for the appearance of chromospheric "superwinds" arises.

  John Haiducek: Can global MHD be used to predict substorms?

Abstract: Magnetospheric substorms consist of an explosive release of energy within the magnetotail. This results in transient field-aligned currents, which are a source for geomagnetically induced currents that threaten power grids. Magnetohydrodynamic (MHD) models have been used in the past to simulate substorms. However, the existing examples of substorms modeled with MHD consist of case studies with at most several events. This talk presents simulation results that aim to evaluate whether MHD is able to reproduce observed substorms in a consistent way. The simulation uses one month of observed solar wind data as input to the BATS-R-US MHD model, coupled to an inner magnetosphere model (Rice Convection Model) and an ionospheric electrodynamics model (Ridley Ionosphere Model) through the Space Weather Modeling Framework. I will present comparisons of simulation output with observations, evaluating the model in terms of its ability to predict the timing and strength of observed substorms.

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