Wine and Cheese Spring 2015

This page records the schedule, titles and abstracts of the JHU/STScI CAS Astrophysics Wine & Cheese Series in Spring 2015.

26 Jan 2015

Ingyin Zaw

Probing the Central Parsec of Active Galactic Nuclei with Water Masers
Determining the geometry and dynamics of the inner-most parsec of active galactic nuclei (AGN) is critical for understanding accretion and the relationship between the AGN and host galaxy. Water maser emission at 22 GHz provides a unique tracer, resolvable in position and velocity, of warm, dense molecular gas ~0.1-1.0 pc from the central engine. Furthermore, water masers exist in the narrow temperature range of ~400-1000K and can be used to probe the temperature and temperature gradient inside the AGN disk. I will discuss i) a test of disk heating in accretion models, using maser spectra and VLBI maps, ii) a study of the flow of material in NGC 4945, combining maser VLBI maps and multi-wavelength data, and iii) a search for new maser systems in the Southern Hemisphere, the Tidbinbilla AGN Maser Survey (TAMS).

Naoki Bessho

Particle acceleration during magnetic reconnection in ultrarelativistic electron-positron plasmas
In pulsar winds and jets from AGNs, plasma is considered to be composed of ultrarelativistic electrons and positrons with their Lorentz factors 10^3 to 10^6. How these high energy particles are produced is an open question, and magnetic reconnection is one of mechanisms to accelerate particles. We study magnetic reconnection in ultrarelativistic electron-positron plasmas by means of 2-D simulations that include kinetics of particle motion, and investigate particle acceleration mechanisms and energy spectra of accelerated particles.

02 Feb 2015

Marius Millea

TBD
TBD

Colin Hill

TBD
TBD

09 Feb 2015

Rongmon Bordoloi

TBD
TBD

23 Mar 2015

Kendrick Smith

TBD
TBD

04 May 2015

Agnieszka Cieplak

TBD
TBD