• 2018 Feb 14

# ITC Pizza Lunch - Erin Kara (Maryland)

11:00am to 12:00pm

## Location:

Phillips

"Observations of Super-Eddington Accretion in the Local Universe"

Abstract:  Some of the most massive black holes known in the Universe are also the most distant, formed when the Universe was less than a billion years old. This begs the question: how can a ten billion solar mass black holes form in such a short period of time? Rapid accretion at rates exceeding the Eddington Limit—where outward radiation pressure equals to the inward gravitational force—may provide the answer.  Understanding the physics of Super-Eddington accretion is vital for understanding...

• 2018 Feb 13

# ITC Seminar - Anna Schauer ( Uni Heidelberg)

12:00pm to 1:00pm

## Location:

Phillips
"The influence of streaming velocities on the formation of the first stars and black holes"

The so-called streaming velocities are relative velocities between
baryons and dark matter, originating from a second-order perturbation
effect at recombination. In regions with high streaming velocities,
the halo mass function is shifted to lower masses in the early Universe.
I will give an overview of how streaming velocities delay the formation
of Population III stars and show that regions with high streaming velocity
might be good environments for the formation of direct... Read more about ITC Seminar - Anna Schauer ( Uni Heidelberg)
• 2018 Feb 12

# Special ITC Colloquium - Robert Scherrer

2:00pm to 3:00pm

## Location:

Phillips
“The Primordial Lithium Problem”

Abstract: Big bang nucleosynthesis (BBN) remains one of the major pillars of modern cosmology. A comparison of predicted and observationally-inferred primordial 2H and 4He abundances implies a baryon density in excellent agreement with the density inferred from the cosmic microwave background. However, there is one piece of the puzzle that does not quite fit: BBN predicts a primordial 7Li abundance that is roughly three times higher than the observationally-inferred abundance. This has been dubbed the primordial...
• 2018 Feb 12

# ITC Seminar - Jing Luan (Berkeley)

12:00pm to 1:00pm

## Location:

Phillips
"DAVs: Red Edge & Outbursts"

Abstract: As established by ground based surveys, white dwarfs with hydrogen atmospheres pulsate as they cool across the temperature range, $12500K< Teff < 10800K$. Known as DAVs or ZZ Ceti stars, their oscillations are attributed to overstable g-modes excited by convective driving. The...
• 2018 Feb 08

# ITC Luncheon

12:30pm to 1:30pm

## Location:

Phillips

* Blakesley Burkhart (ITC): "The Photon Underproduction Crisis Solved: The Effect of AGN Feedback on the Low Redshift Lyman-alpha Forest"

* Heino Falcke (Radbound University): "Radio Measurements of the Composition of High-Energy Cosmic Rays with LOFAR"

* Michael Joyce (LPNHE, Sorbonne Université, Paris): “Cold Quasi-spherical Gravitational Collapse Revisited"

* Meng Gu (CfA):  ''Low Metallicities and Old Ages for Three Ultra-Diffuse Galaxies in the Coma Cluster''

• 2018 Feb 08

# ITC Colloquium Michael Joyce (Paris)

11:00am to 12:00pm

## Location:

Pratt
"Dark matter clustering in the dissipationless limit"

An accurate description and understanding of matter clustering in the strongly non-linear regime, even neglecting baryonic effects, remains a problem which is relevant to cosmology and of fundamental interest. My talk will be structured around...
• 2018 Feb 07

# ITC Pizza Lunch

11:00am to 12:00pm

## Location:

Phillips

Aaron Dotter (CfA)
Title: How stellar winds affect stellar evolution

Abstract: I will begin with a brief review of the different mechanisms by which stars lose mass.  I will then describe how stellar winds influence stellar evolution across the H-R diagram.  I will mention the effect of stellar winds as they relate to galactic chemical evolution.

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Cecilia Garraffo (CfA)
Title: The Revolution Revolution: towards a complete stellar spin-down model

• 2018 Feb 06

# ITC Seminar - Myoungwon Jeon (U. Arizona)

12:00pm to 1:00pm

## Location:

Phillips
"Formation of the First Galaxies and their Connection to Local Dwarfs"

Abstract: Formation of the First Galaxies and their Connection to Local DwarfsAbstract: One of the biggest challenges in modern cosmology is to understand the first generation of stars and galaxies that formed during the cosmic Dark Ages. Since they reside in the observationally unexplored territory, we need to predict the properties of the first galaxies by pushing numerical simulations to new levels of physical realism and detail. In this talk, I will present the results of our...
• 2018 Feb 01

# ITC Luncheon

12:30pm to 1:30pm

## Location:

Phillips

* Maciek Wielgus (BHI):"Characterizing Sgr A* Time Variability with the Event Horizon Telescope"

* Jamie Bock (Caltech): "Update on BICEP-Keck CMB Polarization Measurements"

* Saurabh Singh (RRI): "SARAS 2: Constraining Cosmic Dawn and Cosmological Reionization via the Global Redshifted 21-cm Signal"

* Chris McKee (Berkeley): "The Galactic Corona"

• 2018 Feb 01

# ITC Colloquium Chris McKee (Berkeley)

11:00am to 12:00pm

## Location:

Pratt
"How Stars Form"

Stars are the atoms of the universe. The process by which stars form is at the nexus of astrophysics since they are believed to be responsible for the re-ionization of the universe, they created the...