Past Events in 2018

Sniffing Alien Atmospheres: Exoplanet Spectrophotometry (from Ground-, Airborne- and Space-Based Observatories)

Date: 
Wednesday, January 31, 2018 - 9:00am PST
Speaker: 
Daniel Angerhausen
Affiliation: 
University of Bern
Location: 
N/A
Event Type: 
Teletalk

In my presentation I will give a short introduction to the science of extrasolar planets, in particular the technique of transit, eclipse and phasecurve spectro-photometry.  I will describe my various projects in this emerging field using state of the art spectroscopic and photometric instruments on the largest ground based telescopes, the 'flying telescope' SOFIA (Stratospheric Observatory for Infrared Astronomy) and the Kepler and Hubble space telescopes.

High Spectral Resolution SOFIA/EXES Observations of C2H2 Towards Orion IRc2

Date: 
Wednesday, February 07, 2018 - 9:00am PST
Speaker: 
Naseem Rangwala
Affiliation: 
NASA ARC
Location: 
N/A
Event Type: 
Teletalk

Acetylene (C2H2) is one of the primary building blocks in the formation of larger hydrocarbons, ring molecules and PAHs in the interstellar medium (ISM). This is especially true for the formation of complex organic molecules (important for life) in hot molecular cores, which are the warm, dense regions surrounding massive protostars. Because C2H2 has no permanent dipole moment, it can only be observed via transitions in the mid-infrared (MIR). High spectral resolution is required to resolve the individual ro-vibrational transitions.

Fifty-four Years of Adventures in Infrared Astronomy

Date: 
Wednesday, February 07, 2018 - 3:30pm PST
Speaker: 
Eric Becklin
Affiliation: 
SOFIA/USRA
Location: 
N232 R103
Event Type: 
Colloquium

My adventures in infrared astronomy started when I was a grad student in 1965 with the discovery of an infrared-bright object (now known as the Becklin-Neugebauer Object) in the Orion Nebula. In 1966, I made the first measurements of the infrared radiation from the center of the Milky Way Galaxy.

Imaging the Surfaces of Stars

Date: 
Wednesday, February 14, 2018 - 3:30pm PST
Speaker: 
John Monnier
Affiliation: 
University of Michigan
Location: 
N232 R227
Event Type: 
Colloquium

Using long-baseline interferometry, we can beat telescope diffraction and atmospheric turbulence to  image stars and their environments with sub-milli-arcsecond resolution.  The Georgia State University CHARA Array on Mt.

Massive Stars--An Exploration Across the HR Diagram

Date: 
Thursday, February 15, 2018 - 1:30pm PST
Speaker: 
Michael Gordon
Affiliation: 
University of Minnesota
Location: 
N232 R227
Event Type: 
Seminar

To what extent mass loss and periods of enhanced stellar outflow can influence the terminal state of the most massive stars remains an open question in the fields of stellar physics, chemical enrichment of the Local Universe, and supernova research. For my dissertation, I focus on characterizing the stellar ejecta around supergiants through a combination of observing techniques.

Hunting Galaxies in the Hurricane Zone

Date: 
Friday, February 16, 2018 - 1:30pm PST
Speaker: 
Robert Minchin
Affiliation: 
Arecibo Observatory
Location: 
N232 R227
Event Type: 
Seminar

The Arecibo Galaxy Environment Survey (AGES) is using the Arecibo L-band Feed Array to search for and study galaxies and gas clouds in different environments using the 21-cm line of neutral hydrogen. I will discuss the results coming out of AGES, including the Virgo cluster, where we have found a population of dark clouds, analysis of our sample of isolated galaxies, and our newest results from the NGC 7619 field. I will also give an update on the recovery process at Arecibo Observatory following Hurricane Maria in September.

The New GREAT SOFIA Scenario With 4GREAT

Date: 
Wednesday, February 21, 2018 - 9:00am PST
Speaker: 
Carlos A. Durán
Affiliation: 
MPIfR-Bonn
Location: 
N/A
Event Type: 
Teletalk

The German REceiver for Astronomy at Terahertz frequencies has been successfully in service onboard SOFIA since 2011. GREAT, with its modular approach, is composed of a group of cryostats containing detectors for different frequency bands between 1.25 and 4.7 THz. Individual cryostats are then grouped in pairs. 4GREAT, a new member of the GREAT constellation, is a four-color single-pixel- detector. Two channels, CH1 and CH2, are implemented using spare flight mixers of Herschel-Heterodyne Instrument for the Far-Infrared: HIFI band 1 (492– 635 GHz) and band 4 (892-1100 GHz).

Water in the Early Solar System: Infrared studies of aqueously altered and minimally processed asteroids and meteorites

Date: 
Wednesday, February 21, 2018 - 3:30pm PST
Speaker: 
Maggie McAdam
Affiliation: 
Norther Arizona University
Location: 
N232 R103
Event Type: 
Colloquium

Meteorites and asteroids preserve information about the early solar system including accretion processes and parent body processes active on asteroids at these early times.  One process of interest is aqueous alteration. This is the chemical reaction between coaccreted water and silicates producing hydrated minerals. Some carbonaceous chondrites have experienced extensive interactions with water through this process.

The Dynamic Infrared Sky: A Perspective of Planet Formation

Date: 
Thursday, February 22, 2018 - 1:30pm PST
Speaker: 
Huan Meng
Affiliation: 
University of Arizona
Location: 
N232 R227
Event Type: 
Seminar

The last decade has seen revolutionary discoveries of thousands of exoplanets in hundreds of multi-planet systems. It becomes clear that large planets very close to their central stars are surprisingly common. Their presence is incompatible with, and brings serious challenges to old wisdom of planet formation. Nonetheless, the solar system remains our best understood planetary system and the basis of most planet formation models. Therefore, it is of critical importance to place the solar system in proper context to better understand planet formation in general.

Analysis of Extreme Star Formation Environments in the Large Magellanic Cloud

Date: 
Friday, February 23, 2018 - 1:30pm PST
Speaker: 
Isha Nayak
Affiliation: 
Johns Hopkins University
Location: 
N232 R103
Event Type: 
Seminar

My thesis is on three extreme star forming environments in the Large Magellanic Cloud: 30 Doradus, N159, and N79. These three regions are at different evolutionary stage of forming stars. N79 is at a very young stage, just starting its star formation activity. N159 is currently actively forming several massive YSOs. And 30 Doradus has already passed it peak star formation, and several protostars are no longer shrouded by gas and dust, and are starting to be more visible in the optical wavelengths. I analyze the CO molecular gas clouds with ALMA in 30 Doradus, N159, and N79.

SAMI and friends: advancements in multi-object integral-field spectroscopy and other novel astrophotonic developments

Date: 
Tuesday, February 27, 2018 - 1:30pm PST
Speaker: 
Sam Richards
Affiliation: 
SOFIA/USRA
Location: 
N232 R227
Event Type: 
Seminar

Traditionally there are two ways to obtain galaxy spectra with optical fibres: (a) 1000 fibres on 1000 galaxies (b) 1000 fibres on 1 galaxy. The former lacks spatial information, and the latter lacks sample sizes. This decade has seen the development of new instruments that go for the middle ground: 10 fibre bundles of 100 fibres each on 10 galaxies, providing spatial spectroscopy on large samples of near-by galaxies.

Illuminating Gravitational Waves

Date: 
Wednesday, February 28, 2018 - 3:30pm PST
Speaker: 
Mansi Kasliwal
Affiliation: 
CalTech
Location: 
N232 R103
Event Type: 
Colloquium

On August 17 2017, for the first time, an electromagnetic counterpart to gravitational waves was detected. Two neutron stars merged and lit up the entire electromagnetic spectrum, from gamma-rays to the radio. The infrared signature vividly demonstrates that neutron star mergers are indeed the long-sought production sites that forge heavy elements by r-process nucleosynthesis.

Constraining the Post-Thermal Pulse Mass-Loss History of R Scl with SOFIA/FORCAST

Date: 
Wednesday, March 07, 2018 - 9:00am PST
Speaker: 
Matt Hankins
Affiliation: 
Cornell University
Location: 
N/A
Event Type: 
Teletalk

R Sculptoris (R Scl) is a nearby (~270 pc) carbon star with a massive circumstellar shell which is thought to have been produced by a thermal pulse event ∼2000 years ago. We observed R Scl with the Faint Object InfraRed CAMera for the SOFIA Telescope (FORCAST) at 19.7, 25.2, 31.5, 34.8, and 37.1 μm to study its circumstellar dust emission. Maps of the infrared emission were used to examine the morphology and temperature structure of the spatially extended dust emission.

Observing the signature of a single prolific r-process event in an ultra-faint dwarf galaxy

Date: 
Wednesday, March 07, 2018 - 3:30pm PST
Speaker: 
Anna Frebel
Affiliation: 
MIT
Location: 
N232 R103
Event Type: 
Colloquium

The heaviest chemical elements in the periodic table are synthesized through the rapid neutron-capture (r-) process but the astrophysical site where r-process nucleosynthesis occurs is still unknown. The best candidate sites are ordinary core-collapse supernovae and mergers of binary neutron stars. Through their stars, 13 billion year old ultra-faint dwarf galaxies preserve a "fossil" record of early chemical enrichment that provides the means to isolate and study clean signatures of individual nucleosynthesis events.

Bayesian Hierarchical Modeling in Astronomy: Application to Galaxy Evolution

Date: 
Wednesday, March 14, 2018 - 3:30pm PDT
Speaker: 
Chris Miller
Affiliation: 
University of Michigan
Location: 
N232 R227
Event Type: 
Colloquium

Modern astronomical data sets provide a wealth of data and well-grounded theoretical models describing those data. Our models provide a deeper (multi-level) statistical hierarchy which is allowing researchers to leverage information about the hyper-parameters and hyper-priors in astronomical Bayesian analyses. I will discuss two recent applications of Bayesian Hierarchical Modeling to address how galaxies evolve in clustered environments.

A Submillimeter View Into a Magnetic and Turbulent Universe

Date: 
Thursday, March 15, 2018 - 1:30pm PDT
Speaker: 
Simon Coudé
Affiliation: 
Université de Montréal
Location: 
N232 R227
Event Type: 
Seminar

Astronomy at far-infrared and submillimeter wavelengths offers a unique window to study the physical properties of a wide variety of interstellar environments, ranging from the stellar nurseries in our Galaxy to the relativistic jets of faraway blazars. Polarimetric observations in particular can probe the magnetic and turbulent properties of these environments, providing insights into notoriously challenging topics such as the role of magnetic fields in the formation of stars and their planets.

The Cool Side of Galactic Winds

Date: 
Wednesday, March 21, 2018 - 3:30pm PDT
Speaker: 
Sylvain Veilleux
Affiliation: 
University of Maryland
Location: 
N232 R103
Event Type: 
Colloquium

Galactic winds impact ongoing star formation and black hole activity in their hosts and deposit mass and energy into their halos and the intergalactic medium.  Major outstanding questions remain, however, about the precise impact that galactic winds make. In particular, the exact nature of the neutral and molecular gas phases in these winds is still unclear. This seminar will highlight the recent discovery of powerful atomic and molecular winds in nearby galaxies and quantify the role of AGN/quasars in driving these winds.

History, Science & Discovery at the Arecibo Observatory

Date: 
Wednesday, March 28, 2018 - 3:30pm PDT
Speaker: 
Joan Schmelz
Affiliation: 
USRA
Location: 
N232 R103
Event Type: 
Colloquium

The Arecibo Observatory celebrated its 50th anniversary in 2013 and continues to do cutting-edge research in radio astronomy, planetary radar, and atmospheric science. Early discoveries include the 33-ms period of the pulsar in the Crab Nebula supernova remnant and the 59-day rotation rate of the planet Mercury. Later discoveries include the first binary pulsar, the first radar maps of Venus, the first megamaser galaxy, the first millisecond pulsar, and the first extrasolar planet.

Non-Zeeman Circular Polarization of Rotational Molecular Spectral Lines

Date: 
Wednesday, April 04, 2018 - 3:30pm PDT
Speaker: 
Martin Houde
Affiliation: 
University of Western Ontario
Location: 
N232 R103
Event Type: 
Colloquium

In this presentation I will discuss the recent discovery of circular polarization signals in the rotational line profiles of molecules that are negligibly sensitive to the Zeeman effect. Our initial findings obtained for CO in the Orion KL star-forming region with the Caltech Submillimeter Observatory were followed with similar detections for two transitions of CO in an exhaustive study of the supernova remnant IC 443 (G), obtained with the IRAM 30m.

New Cosmological View of Dark Matter, which Strangely and Slowly Decays

Date: 
Tuesday, April 10, 2018 - 3:30pm PDT
Speaker: 
Sir Roger Penrose
Affiliation: 
Oxford
Location: 
N201
Event Type: 
Colloquium

Sir Roger Penrose will give a talk on his latest research and provide an insight into the thinking of a modern day theoretical physicist. Is the Universe destined to collapse, ending in a big crunch or to expand indefinitely until it homogenizes in a heat death? Roger will explain a third alternative, the cosmological conformal cyclic cosmology (CCC) scheme – where the Universe evolves through eons, each ending in the decay of mass and beginning again with new Big Bang.

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