YCAA Logo
YCAA Logo
The Crab Nebula in Blue and White Credit & Copyright: Jay Gallagher (U. Wisc.),
The Crab Nebula in Blue and White Credit & Copyright: Jay Gallagher (U. Wisc.),
Interstellar Dust-Bunnies of NGC 891 Credit: C. Howk & B. Savage (Wisconsin);
Interstellar Dust-Bunnies of NGC 891 Credit: C. Howk & B. Savage (Wisconsin);
Hubble. Credit: R. Williams (STScI), the Hubble Deep Field-South Team, and NASA
Hubble. Credit: R. Williams (STScI), the Hubble Deep Field-South Team, and NASA
Dumbell. Credit & (c): Michael Pierce (Indiana U.) et al., WIYN, AURA, NOAO, NSF
Dumbell. Credit & (c): Michael Pierce (Indiana U.) et al., WIYN, AURA, NOAO, NSF
Abell 39.    (c): George Jacoby (WIYN Obs.) et al., WIYN, AURA, NOAO, NSF
Abell 39. (c): George Jacoby (WIYN Obs.) et al., WIYN, AURA, NOAO, NSF
Bubbling. Credit: Jeffrey Kenney (Yale) et al., WFPC2, HST NASA
Bubbling. Credit: Jeffrey Kenney (Yale) et al., WFPC2, HST NASA

Mailing Address

Yale Center for Astronomy and Astrophysics
Physics Department
P.O. Box 208120
New Haven, CT 06520-8120

Campus Address

260 Whitney Avenue
454 J.W. Gibbs Laboratory

Telephone: (203) 432-3392

Fax: 203) 432-3824

E-mail: ycaa@yale.edu

Upcoming YCAA Seminars

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Updated: 2 hours 31 min ago

YCAA Seminar: Maureen Teyssier, Rutgers University Title: "Stellar Gradients and the Evolution of Dwarf Galaxies" - Tue, October 28, 2014

2 hours 31 min ago
When: Tuesday, October 28, 2014 2:30 PM - 3:30 PM
Where:
   Bass Center for Molecular and Structural Biology (BASS), 305 BASS
   266 Whitney Ave., New Haven, CT 06511
   (Location is wheelchair accessible)
   Tea will be served at 2:00pm in the hallway outside BASS 305
Tags: astrophysics, science, seminar, talk

Speaker/Performer: Postdoc Maureen Teyssier

Description: Abstract: Isolated field dwarfs in the Local Group of galaxies are ideal places to test the physics of star formation and the role of stellar/supernova feedback. Recent advances in the modeling of dwarfs have allowed simulators to explain a number of long-standing puzzles related to dwarf galaxy observations (like the existence of bulgeless disks and dark matter cores). We present results from high resolution, fully cosmological simulations (force resolutions under 100pc, dark matter mass resolutions 10^4 solar masses) of isolated dwarf galaxies that successfully match observational trends, and use them to explain a number of puzzles presented by dwarf galaxy observations. We show that the same processes that act to create dark matter cores also expand the stellar orbits. The redistribution of stars allows us to match the observed dwarf galaxy gradients. In particular, we show that dwarf galaxies form from the inside out, despite appearing to form from the outside in.

Open To: General Public
Contact Information:
   Laurelyn Celone
   
   laurelyn.celone@yale.edu
   

YCAA Seminar: Greg Stinson, MPIA, Heidelberg, Title: "A Critical Phase in Galaxy Formation" - Tue, October 21, 2014

Tue, 10/21/2014 - 5:20am
When: Tuesday, October 21, 2014 2:30 PM - 3:30 PM
Where:
   Bass Center for Molecular and Structural Biology (BASS), 305 BASS
   266 Whitney Ave., New Haven, CT 06511
   (Location is wheelchair accessible)
   Tea will be served at 2:00pm on the 3rd floor hallway outside the auditorium BASS
Tags: astrophysics, science, seminar, talk

Speaker/Performer: Greg Stinson, Max Planck Insitute for Astronomy, Heidelberg

Description: Abstract:
As galaxies grow and evolve, they go through a violent phase of their evolution where intense star formation drives outflows. I will examine this phase using cosmological galaxy formation simulations. The simulations show that starbursts and outflows have implications for many observed properties of galaxies including their gaseous halos, morphology, potential, and star formation history.

Contact Information:
   Laurelyn Celone
   
   laurelyn.celone@yale.edu
   

YCAA Seminar: Dominik Riechers, Cornell University, Title: Fueling Cosmic Star Formation: The Cold Interstellar Medium in Star-Forming Galaxies back to the First Giga-Year of Cosmic Time - Tue, October 14, 2014

Tue, 10/14/2014 - 5:18am
When: Tuesday, October 14, 2014 2:30 PM - 3:30 PM
Where:
   Bass Center for Molecular and Structural Biology (BASS), 305 BASS
   266 Whitney Ave., New Haven, CT 06511
   (Location is wheelchair accessible)
   Tea will be served at 2:00pm in the hallway outside BASS 305
Tags: astrophysics, science, seminar, talk

Speaker/Performer: Assistant Professor Dominik Riechers

Description: Abstract: Dusty starburst galaxies at very high redshift represent an important phase in the early evolution of massive galaxies. They typically represent large-scale, gas-rich major mergers that trigger intense, short-lived bursts of star formation, which consume most of the available gas and drive the morphological transition to spheroids. At early cosmic epochs, these hyper-luminous galaxies commonly trace regions of high galaxy overdensity, and may be directly related to the formation of galaxy clusters and their giant central ellipticals. Molecular and atomic gas plays a central role in our understanding of the nature of these often heavily obscured distant systems. It represents the material that stars form out of, and its mass, distribution, excitation, and dynamics provide crucial insight into the physical processes that support the ongoing star formation and stellar mass buildup. I will discuss the most recent progress in studies of the cold gas content of dusty starburst galaxies at high redshift, back to the first billion years of cosmic time using CARMA, the Jansky Very Large Array, the Plateau de Bure interferometer, and the Atacama Large (sub)Millimeter Array (ALMA). I will also highlight our recent successful first detections of the interstellar medium in "normal" (~L*) galaxies at z>5 with ALMA, and discuss the impact of our findings on future studies back to even earlier epochs.

Open To: General Public
Contact Information:
   Laurelyn Celone
   
   laurelyn.celone@yale.edu
   

YCAA Seminar: Peter Behroozi, Space Telescope Science Institute, Title: "Insights into Galaxy Formation from z=15 to the Present" - Tue, October 7, 2014

Tue, 10/07/2014 - 5:57am
When: Tuesday, October 7, 2014 2:30 PM - 3:30 PM
Where:
   Bass Center for Molecular and Structural Biology (BASS), 305 BASS
   266 Whitney Ave., New Haven, CT 06511
   (Location is wheelchair accessible)
   Tea will be served at 2:30pm in the hallway outside BASS 305
Tags: astrophysics, science, seminar, talk

Speaker/Performer: Giacconi Postdoctoral Fellow Peter Behroozi

Description: Abstract:We show that the ratio of galaxies' specific star formation rates to their host halos' specific mass accretion rates strongly constrains how the galaxies' stellar masses, specific star formation rates, and host halo masses evolve over cosmic time. This evolutionary constraint provides a simple way to probe z>8 galaxy populations without direct observations, and predicts that JWST should see galaxies above 10^8 Msun even to z=15. We also discuss using close galaxy pairs as a probe for major halo mergers at very low redshifts (z<0.05). We find no evidence that the recent halo formation history influences the quenched fraction of L* galaxies at z=0, though we do find intriguing SFR enhancement signatures for star-forming hosts.

Open To: General Public
Contact Information:
   Laurelyn Celone
   
   laurelyn.celone@yale.edu
   

YCAA Seminar: Naveen Reddy, University of California, Riverside Title:"Mearurements of the Dust Attenuation Curve at Redshifts z~1.4-2.6 from the MOSFIRE Deep Evolution Field (MOSDEF) Survey" - Tue, September 30, 2014

Tue, 09/30/2014 - 5:58am
When: Tuesday, September 30, 2014 2:30 PM - 3:30 PM
Where:
   Bass Center for Molecular and Structural Biology (BASS), 305 BASS
   266 Whitney Ave., New Haven, CT 06511
   (Location is wheelchair accessible)
   Tea will be served at 2:00pm in the hallway outside BASS 305
Tags: astrophysics, science, seminar, talk

Speaker/Performer: Assistant Professor Naveen Reddy

Description: Abstract: I will present results on the dust attenuation curve of
redshift z~2 galaxies using early results from the MOSFIRE Deep
Evolution Field (MOSDEF) survey. Our sample consists of 112
star-forming galaxies with nebular spectroscopic redshifts in the
range z = 1.36 − 2.59 and high S/N measurements of the Hα and
Hβ emission lines obtained with the MOSFIRE spectrograph on the
Keck I telescope. Coupled with deep multi-wavelength photometry,
we investigate the impact of dust attenuation on the stellar continuum
and, by constructing composite spectral energy distributions (SEDs)
of galaxies in bins of specific star-formation rate (SFR/M∗) and Balmer
optical depth, we provide the first direct constraints on the shape of the
dust attenuation curve over the full wavelength range from the UV
through near-IR at high redshift. Our results imply an attenuation
curve that is similar in shape to the SMC extinction curve at wavelengths
λ > 2500 Angstroms, and exhibits a rise in the UV that is steeper than that
of the starburst attenuation curve of Calzetti et al. (2000) and shallower
than that of the SMC extinction curve. I will discuss the implications for
these differences in the attenuation curve for the stellar populations
and star-formation rates of high-redshift galaxies.

Open To: General Public
Contact Information:
   Laurelyn Celone
   
   laurelyn.celone@yale.edu
   

YCAA Seminar: Andrew Hearin, Yale University, Title: The Dark side of Galaxy Evolution" - Tue, September 23, 2014

Tue, 09/23/2014 - 6:20am
When: Tuesday, September 23, 2014 2:30 PM - 3:30 PM
Where:
   Bass Center for Molecular and Structural Biology (BASS), 305 BASS
   266 Whitney Ave., New Haven, CT 06511
   (Location is wheelchair accessible)
   Tea will be served at 2:00pm in the hallway outside BASS 305
Tags: astrophysics, science, seminar, talk

Speaker/Performer: YCAA Prize Postdoctoral Fellow Andrew Hearin

Description: Abstract: In this talk, I review the basic physical picture of galaxy formation offered by empirical models connecting galaxies to the dark matter halos they live in. I show that many of the well-established trends in galaxy evolution can be understood through quite simple models of the galaxy-halo connection. I will give examples of how these simple models can be employed to constrain cosmological parameters, as well as how they inform more complex semi-analytical models of galaxy formation and state-of-the-art hydrodynamical simulations. However, recent observational and theoretical developments have revealed that the traditional approach to the galaxy-halo connection is too simplistic to reliably model observed trends in star-formation and quenching at low redshift. This inadequacy presents a new challenge both to the theory of large-scale structure, and to the precision cosmology program. I conclude by outlining a plan for the path towards a new generation of galaxy-halo models, so that we may reap the benefits of deep and wide-field galaxy surveys to robustly constrain cosmological parameters with measurements of large-scale structure, and to develop a more complete picture of galaxy evolution.

Open To: General Public
Contact Information:
   Laurelyn Celone
   
   laurelyn.celone@yale.edu
   

YCAA Seminar: Shirley Ho, Carnegie Mellon University, Title: How to Learn to Love the BOSS" - Tue, September 16, 2014

Tue, 09/16/2014 - 6:25am
When: Tuesday, September 16, 2014 2:30 PM - 3:30 PM
Where:
   Bass Center for Molecular and Structural Biology (BASS), 305 BASS
   266 Whitney Ave., New Haven, CT 06511
   (Location is wheelchair accessible)
   Tea will be served at 2:00pm in the hallway outside BASS 305
Tags: astrophysics, science, seminar, talk

Speaker/Performer: Professor Shirley Ho

Description: Abstract: Baryon Oscillations Spectroscopic Survey have just finished surveying 10,000 square degrees, containing over 1 million galaxies within the redshift range of 0.2
Open To: General Public
Contact Information:
   Laurelyn Celone
   
   laurelyn.celone@yale.edu
   

Special YCAA Seminar: "Measuring AGN Inner Structure and General Relativistic Effects with NuStar" Guido Risaliti - Thu, July 17, 2014

Thu, 07/17/2014 - 5:45am
When: Thursday, July 17, 2014 2:00 PM
Where:
   J.W. Gibbs Laboratory, 164 JWG
   260 Whitney Ave., New Haven, CT 06520-8120
   (Location is wheelchair accessible)
Tags: astrophysics, science, seminar, talk

Speaker/Performer: Guido Risaliti

Description: Abstract:I will show the latest results from the NuSTAR observing program of bright AGN, focusing on measurements of general relativistic effects. I will show how precise BH spin measurements are possible for AGN with strong reflection continua, with and without simultaneous XMM-Newton observations. I will also discuss some preliminary analysis of the structure and size of the X-ray emitting corona, estimated through self-consistent disk+corona emission models.

Open To: General Public
Contact Information:
   Laurelyn Celone
   
   laurelyn.celone@yale.edu