Weekly Calendar of Events

APRIL 14 - 18, 2014


12:30 pm: High Energy Astrophysics Division Lunch Talk. "Feeding and Feedback in Nearby Active Galaxies Tracing Co-evolution of Supermassive Black Holes and Galaxies," Thaisa Storchi-Bergmann, University of Rio Grande del Sul. Pratt Conference Room.

Abstract: A fundamental role is attributed to supermassive black holes (SMBH) and their feedback in the evolution of galaxies. But theoretical models make broad assumptions about the physical processes involved, which occur when the SMBH is being fed in Active Galactic Nuclei (AGN). In search of constraints for these processes,my research group has been mapping the gas kinematics and stellar population properties within the inner few hundred parsecs of nearby AGN hosts on scales of 10-100 pc using integral field spectroscopy. I will discuss recent results that include compact molecular disks and gas inflows along nuclear spirals. In many cases, we find ~100 pc scale nuclear rings of recently formed stars that can be interpreted as signatures of co-evolution of the host galaxy and its AGN. Outflows are found around most AGN, but while frequently the ionized gas emission has a conical or elongated morphology, consistent with an "ionization cone", extending for several hundred pcs, the region in outflow is much more compact (100-200 pc) and can be spherical or "equatorial" - perpendicular to the ionization cone and radio jet.

1:00 pm: ITC Pizza Lunch Talk on Time Domain Astronomy. "Relativistic SNe, Hypernovae and Sub-energetic Gamma-ray Bursts," Drs. Raffaella Margutti and Sayan Chakraborti, CfA. Phillips Auditorium.


11:00 am: ITC Colloquium. "Massive Black Holes in Cosmic Structure Formation," Tiziana Di Matteo, Carnegie Mellon University. Pratt Conference Room.

Abstract: I will present state-of-the-art cosmological hydrodynamical simulations of galaxy formation. I will discuss the extraordinary prospect that cosmology, i.e. the science of the Gigaparsec horizon, will lead to predictions for the formation of the first quasars and galaxies, from the smallest to the rarest and most luminous.

4:00 pm: Colloquium. Payne-Gaposchkin Lecture: "Andromeda's Dust," Prof. Bruce Draine, Princeton University. Preceded by tea at 3:30 pm. Phillips Auditorium.

Abstract: Infrared observations from Spitzer Space Telescope and Herschel Space Observatory are used to study the interstellar dust in M31. A physical dust model is used to map the dust surface density, dust/gas ratio, starlight heating intensity, and the PAH abundance, out to R=25 kpc from the center of M31. The dust/gas ratio declines smoothly with increasing galactocentric radius, decreasing by almost a factor of ten from R=0 to R=25 kpc, following the metallicity of the gas. The dust serves as a photometer to measure the intensity of the starlight heating the dust. Within the central kpc the starlight intensity estimated from the observed dust SED is in good agreement with the directly-observed bulge starlight -- a validation of the dust model. Nature has kindly place an AGN behind the dusty disk of M31. Dust-scattered X-ray photons from this AGN could be used to get a geometric distance to M31.

7:30 pm: Monthly Observatory Night. "Jupiter and Mars Return!" Dr. Ruth Murray-Clay, CfA. The lecture will be followed by telescopic observing, weather permitting. No tickets or reservations are necessary; however, seating is to the capacity of the hall. Doors open at 7:00 pm. Phillips Auditorium.

Abstract: The King of Planets and the God of War dominate the night sky this spring. These two neighboring worlds contrast each other dramatically - one small and rocky, one huge and gaseous. Learn about the differences between gas-giant and terrestrial planets, both in our solar system and beyond, from planetary scientist Ruth Murray-Clay, and then observe both of these worlds through telescopes to highlight this memorable evening.


2:30 pm: Solar, Stellar, and Planetary Sciences Division Seminar. "Field RR Lyrae stars - Tracers of the Galaxy," Karen Kinemuchi, Apache Point Observatory. Pratt Conference Room.

Abstract: RR Lyrae variable stars are ubiquitous standard candles within the Milky Way Galaxy. First discovered in Galactic globular clusters, much work has been done in over 100 years to characterize RR Lyrae stars with their parent environments. Field RR Lyrae stars associate more with the general Galactic components of the halo, disk, and bulge. Extrapolating what we know from cluster RR Lyrae stars, we can infer information for those Galactic components. The chemical and kinematic information from the RR Lyrae stars can give us a idea of the how these stars came to be in their present positions in the Milky Way. These conclusions then provide support to local Galactic formation theories. In this talk, I present a sample of field RR Lyrae stars, mostly found in the Solar neighborhood, but identified as part of the Galactic disk component. I will discuss their characteristics with respect to the globular clusters and the halo, and in context to various disk formation theories for galaxies like the Milky Way.

The Calendar is prepared by the Web Services Group. Entries may be submitted via email to weekly_cal@cfa.


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