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: 1 hour 6 min ago

Time change: Nuclear Particle Astrophysics Seminars: Alessandro Bettini, Laboratorio Subterraneo de Canfranc, Spain, "The Canfranc Underground Laboratory (LSC), Physics and more" - Thu, December 11, 2014

Thu, 12/11/2014 - 5:33am
When: Thursday, December 11, 2014 11:00 AM - 12:00 PM
Where:
   EAL 108 Conference Room (EAL108)
   270 Whitney Avenue, New Haven 06520
   (Location is wheelchair accessible)
Tags: astrophysics, nuclear_physics, particle_theory, science, seminar, talk

Speaker/Performer: Alessandro Bettini

Description: The LSC is a small underground laboratory excavated under the Spanish Pyrenees between a road and unused train tunnels, with 850 m rock overburden. I shall summarise the scientific program we are developing. It includes dark matter search, both searching for annual modulation with NaI detectors (ANAIS) and not with a liquid Ar TPC (ArDM), neutrino-less double beta decay with a high pressure enriched 136Xe TPC (NEXT), deep underground microbiology and under-surface geodynamics and hydrology.

Open To: General Public
Contact Information:
   Karsten Heeger
   
   karsten.heeger@yale.edu
   

YCAA Seminar: Gerard van Belle, Lowell University,Directly Determined Linear Radii, Effective Temperatures, and Shapes of Stars from Long-Baseline Optical Interferometry - Tue, December 9, 2014

Tue, 12/09/2014 - 5:34am
When: Tuesday, December 9, 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: Staff Astronomer Gerard van Belle

Description: Abstract:A brief introduction to the concepts of long-baseline optical interferometry (LBI) will be presented, followed by a review of fundamental stellar parameters as directly determined using LBI. Special attention will be paid to the progression of precision over the years of the observables of linear radius and effective temperature, with the current state-of-the-art measures approaching sub-percent levels for hundreds of stars (and being limited primarily by the ancillary data products of distance and bolometric flux, not measured angular size). Discussion will also be presented on the diminishing meaning of these gross parameterizations of stellar atmospheres, as higher-order surface details such as shapes, limb darkening, gravity darkening, and spotting are beginning to be imaged with LBI.

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

Nuclear Particle Astrophysics Seminars: Mark Caprio, Notre Dame, "Emergence of nuclear rotation in ab initio calculations" - Thu, December 4, 2014

Thu, 12/04/2014 - 5:21am
When: Thursday, December 4, 2014 11:00 AM - 12:00 PM
Where:
   EAL 108 Conference Room (EAL108)
   270 Whitney Avenue, New Haven 06520
   (Location is wheelchair accessible)
Tags: astrophysics, nuclear_physics, particle_theory, science, seminar, talk

Speaker/Performer: Mark Caprio

Description: A fundamental goal in nuclear theory is to obtain an ab initio description of the nucleus--that is, to understand the strongly correlated motion of nucleons within the nucleus directly from the underlying interactions of these constituents. Particularly intriguing is the question of how simple excitation patterns, indicating the presence of collective modes, arise out of the complex interactions within the nuclear many-body system. The emergence of rotational bands has recently been observed in ab initio no-core configuration interaction calculations of light nuclei. The results demonstrate the possibility of well-developed rotational structure in such calculations, using realistic nucleon-nucleon interactions, and within finite, computationally-accessible configuration spaces. This talk will focus on results for rotation in both the even-mass and odd-mass Be isotopes, as well as on the challenges of obtaining converged results for observables relevant to rotation.

Contact Information:
   
   
   francesco.iachello@yale.edu
   

YCAA Seminar: Francesca Civano, Yale University Title:"Learning about the High-z Universe with COSMOS X-ray Surveys" - Tue, December 2, 2014

Tue, 12/02/2014 - 5:30am
When: Tuesday, December 2, 2014 2:25 PM - 3:25 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: Research Associate Francesca Civano

Description: Abstract:The equatorial 2 deg2 COSMOS area is the only large field for which a complete, deep, pan-chromatic data set exists, from an outstanding survey effort, and that all large telescopes can observe. During 2013, this pioneering and ambitious COSMOS survey had a major extension, pushing its frontiers via the newly approved Chandra COSMOS Legacy Survey, the second largest Chandra proposal ever approved, plus new deep Spitzer, JVLA and NuSTAR surveys all aimed to study the formation of the structures in the high redshift Universe and the role of active super massive black holes. The Chandra COSMOS-Legacy survey uniformly covers the 1.7 deg2 COSMOS/HST field with 2.8 Ms of Chandra ACIS-I imaging at ~150 ksec depth.
At Chandra energies, we are able to detect unobscured and obscured sources, up to columns of NH=10^23. Therefore, to have a complete selection with no obscuration bias, we employed 3 Megaseconds of NuSTAR time to cover the same Chandra area and have the best unbiased view of the X-ray sky. In this talk, I will present the first results from both surveys focusing on the high-z sample. With the ~4000 sources detected in the X-ray band, we can finally have enough statistic to study Active Galactic Nuclei at high redshift and faint luminosity, using multiple approaches, and learn about their evolution and the Dark Matter halos in which these sources reside.

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

YCAA seminar Sarah Gallagher, University of Western Ontario Title: "Winds, Winds Every Where: Radiatively Driven Outflows from Supermassive Black Holes" - Tue, November 18, 2014

Tue, 11/18/2014 - 5:32am
When: Tuesday, November 18, 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 2:00pm on 3rd floor BASS outside the auditorium hallway
Tags: astrophysics, science, seminar, talk

Speaker/Performer: Professor Sarah Gallagher

Description: Abstract:Supermassive black holes reside in the centers of every massive galaxy. In relatively brief spurts, black holes grow as luminous quasars through the infall of material through an accretion disk. Remarkably, the light from the accretion disk can outshine all of the stars in the host galaxy by a factor of a thousand, and this radiation can also drive energetic mass outflows. Mass ejection in the form of winds or jets appears to be as fundamental to quasar activity as accretion, and can be directly observed in many objects with broadened and blue-shifted UV emission and absorption features. A convincing argument for radiation pressure driving this ionized outflow can be made within the dust sublimation radius. Beyond, radiation pressure is still important, but high energy photons from the central engine can now push on dust grains. This physics underlies the dusty wind picture for the putative obscuring torus. I'll describe our model of the dusty wind and evaluate its success in accounting for observed properties of quasars such their mid-infrared spectral energy distributions, fractions of hidden objects, and column densities of important ions.

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

YCAA Seminar: Kaitlin Kratter, University of Arizona Title:"What we can learn from Planets in Binary Systems" - Tue, November 11, 2014

Tue, 11/11/2014 - 5:29am
When: Tuesday, November 11, 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 Kaitlin Kratter

Description: Abstract:Exoplanet surveys have revealed a surprising array of planetary systems hosted by binary stars. The diversity and architecture of these systems provides insight into the fundamentals of planet formation relevant for a wide range of systems. Moreover, these planets provide an important final boundary condition for our models of star formation, and especially binary formation. I will review the statistics of these surprisingly un-exotic systems, describe the theoretical implications, and discuss the prospects for progress with observational facilities of the future.

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

YCAA Seminar: Octavi Fors,University of North Carolina at Chapel Hill Title: "The Evryscope: The First Minute Cadence, 10,000-Square-Degree FoV, Full-sky Gigapixel-Scale Telescope" - Tue, November 4, 2014

Tue, 11/04/2014 - 5:19am
When: Tuesday, November 4, 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: Octavi Fors

Description: Abstract:"Current time-domain wide-field sky surveys generally operate with few-degree-sized fields and take many individual images to cover large sky areas each night. The Evryscope ("wide-seer"), a new all-sky telescope concept, is presented. It places a pixel on every part of the sky, making it a 7cm telescope pointed at every part of the visible sky simultaneously and with a cadence of 2 minutes. The Evryscope is a gigapixel-scale imager with a 10,200 sq.deg. field of view and an étendue three times larger than the Pan-STARRS sky survey.
Among other sciences cases, the system will search for transiting giant exoplanets around nearby bright stars, rocky planets in the habitable zone of M-dwarfs and Moon-size (or asteroids) objects around white dwarfs, as well as detecting nearby microlensing events, nearby supernovae (shock breakout & pre-outbursts), and gamma-ray burst optical counterparts (before & afterglows, and orphan afterglows).
We will present the current project status, including an update on the Evryscope prototype telescopes which have been operating for the last three years in the Canadian High Arctic, and the detailed design of the under-construction full system."

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

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

Tue, 10/28/2014 - 4:50am
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 - 4:20am
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 - 4:18am
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 - 4:57am
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 - 4:58am
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 - 5:20am
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 - 5:25am
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