Events

Fri, August 18 12:00pm
JILA 10th Floor - Foothills Room
Astrophysics Lunch Seminar
Episodic accretion events in protoplanetary disks due to Hall dead zones

Dan Gole,
JILA
Fri, August 18 3:00pm
JILA X317
JILA Thesis Defense
Photoelectron Spectroscopy of Organic Aromatic Anions

Dan Nelson,
CU Boulder

Abstract/Details

This dissertation reports and interprets the results of experiments in which photoelectron spectroscopy was performed on a variety of aromatic anions. In addition to these photoelectron studies, the results and conclusions of an experiment in which HCl is scattered off atomically flat Au (111) surfaces are also presented.      Photoelectron spectroscopy of the isomers of methylphenoxide reveals that these molecules display minimal vibrational excitation upon photodetachment, accessing the electronic ground and first excited state of the corresponding radicals. The photoelectron spectra of /p-/methylphenoxide reveal a photon energy dependence arising from electron autodetachment. The slow electron velocity map imaging (SEVI) technique was employed to obtain the electron affinities (EAs) of these radicals with an uncertainty of 1.4 meV. Combining the measured EAs with previously measured O–H bond dissociation energies in a thermodynamic cycle allows for the measurement of the acidities of the methylphenols with an uncertainty an order of magnitude smaller than any previous measurement.      The full interpretation of the photoelectron spectra of the isomers of methylenephenoxide presents a far greater challenge with many subtleties. The EAs of/o-/ and /p-/methylenephenoxyl were measured and shown to be ~1 eV lower in energy than for the methylphenoxyls, implying that the electron withdrawing effect of the CH_2 group in the methylenephenoxides attracts electron density from the oxygen site via resonance, as compared to the methylphenoxides. The singlet–triplet splitting of the diradicals /o-/ and/p-/methylenephenoxyl were measured. The acidities of the methylenephenols were measured by acid bracketing. Combining the EAs of the methylenephenoxyls with these acidities allows for a measurement of the weak O-H bond dissociation energy of the methylenephenols. The photoelectron spectra of indolide were obtained and interpreted. The structure of indolide minimally distorts upon electron photodetachment accessing the electronic ground doublet state of indolyl. The EA of indolyl was measured utilizing the SEVI technique with an uncertainty of 1.7 meV. Ring distortion vibrational modes were found to be excited upon electron photodetachment. The previously measured acidity of indole is combined with our measurement of the EA of indolyl to determine the N–H bond dissociation energy of indole.
Fri, August 25 12:00pm
JILA 10th Floor - Foothills Room
Astrophysics Lunch Seminar
Observations of exoplanets and exoplanet atmospheres

Jessica Roberts,
University of Colorado, Boulder
Mon, August 28 4:00pm
JILA Auditorium
APS Colloquium
APS Colloquium Introduction

Colloquium Committee,
Department of Astrophysical and Planetary Sciences

Abstract/Details

TBA
Tue, September 05 3:00pm
JILA 10th Floor - Foothills Room
Astrophysics Lunch Seminar
From Astrophysics to Data Science

Jeffrey Silverman,
Samba TV

Abstract/Details

We are truly in the era of Big Data. The number of data science and analytics job openings has grown rapidly over the past several years and demand looks to continue to be very strong in years to come. Masters and PhD scientists (from all quantitative fields) are extremely well-qualified for such positions. Come learn about the basics of what data science is and what data scientists do, as well as how scientists in academia can become successful candidates for these positions in the tech industry. I'll also share my personal path from NSF astronomy postdoc to gainfully-employed data scientist. Brief Bio: Jeffrey Silverman is a Data Scientist at Samba TV where he uses Big Data to, among other things, figure exactly how many people are really watching Westworld and Game of Thrones. Prior to working at Samba, he went through the Insight Data Science Program in Silicon Valley. Before moving into the tech industry, Jeffrey was an NSF Astronomy & Astrophysics Postdoctoral Fellow at UT Austin and he earned his PhD at UC Berkeley working on exploding stars and dark energy with Prof. Alex Filippenko. Jeffrey is also heavily involved in various science communication and public outreach programs including the March for Science and Project Astro in San Francisco and (as a co-founder and former co-host) Astronomy on Tap Austin.
Wed, September 06 4:00pm
Duane Physics Room G1B20
Physics Department Colloquium
TBA

Juliet Gopinath,
CU EE
Fri, September 08 12:00pm
JILA 10th Floor - Foothills Room
Astrophysics Lunch Seminar
STScI missions including JWST

David Soderblom

Abstract/Details

TBA
Fri, September 08 4:00pm
JILA Auditorium
Phys Chem/Chem Phys Seminar
Joel Eaves, CU Boulder

Joel Eaves,
CU Boulder

Abstract/Details

TBA
Mon, September 11 4:00pm
JILA Auditorium
Astrophysical & Planetary Sciences Seminar
TBA

Keivan Stassun,
Vanderbilt University
Thu, September 14 12:00pm
Duane Physics Room G126
Condensed Matter Seminar
TBA

Chris Laumann,
Boston University
Fri, September 15 12:00pm
JILA 10th Floor - Foothills Room
Astrophysics Lunch Seminar
Development of the Kepler Exoplanet Mission

Dennis Ebbets,
Ball Aerospace
Mon, September 18 4:00pm
JILA Auditorium
Astrophysical & Planetary Sciences Seminar
Planet Nine from Outer Space: Status Update

Konstantin Batygin,
Caltech

Abstract/Details

Over the course of the past two decades, observational surveys have unveiled the intricate orbital structure of the Kuiper Belt, a field of icy bodies orbiting the Sun beyond Neptune. In addition to a host of readily-predictable orbital behavior, the emerging census of trans-Neptunian objects displays dynamical phenomena that cannot be explained by interactions with the known eight-planet Solar System alone. Specifically, the observed physical clustering of orbits with semi-major axes in excess of ∼ 250 AU, the detachment of perihelia of select Kuiper belt objects from Neptune, as well as the dynamical origin of highly inclined/retrograde long-period orbits remain elusive within the context of the classical view of the Solar System. This newly outlined dynamical architecture of the distant solar system points to the existence of planet with mass M9 ∼ 10M⊕ on a moderately inclined orbit with semi-major axis a9 ∼ 400−800 AU and eccentricity e9 ∼ 0.4−0.6. In this talk, I will review the observational motivation, dynamical constraints, and prospects for detection of this proposed object known as Planet Nine.
Thu, September 21 12:00pm
Duane Physics Room G126
Condensed Matter Seminar
TBA

Ravin Bhatt,
Princeton University
Fri, September 22 12:00pm
JILA 10th Floor - Foothills Room
Astrophysics Lunch Seminar
Scaling relations between supermassive Black Holes in the center of galaxies and the properties of their host galaxy

Vardha Bennert,
California Polytechnic State University San Luis Obispo
Fri, September 22 4:00pm
JILA Auditorium
Phys Chem/Chem Phys Seminar
Geoff Blake, California Institute of Technology

Geoff Blake,
California Institute of Technology

Abstract/Details

TBA
Mon, September 25 4:00pm
JILA Auditorium
Astrophysical & Planetary Sciences Seminar
Murmurs from Dormant Black Holes: The Theory and Observation of Tidal Disruption Events

Nick Stone,
Columbia University

Abstract/Details

In recent years, dozens of powerful, multiwavelength transients have been seen from the photometric centers of inactive galactic nuclei. The light curves of these explosions rise and decay over timescales of weeks to months, their generally thermal spectra peak in the UV or soft X-ray, and their bolometric energy output is greater than the vast majority of supernovae. I will review the observational evidence that these flares are tidal disruption events (TDEs), the death throes of stars that have been torn apart by supermassive black holes (SMBHs). I will also present my own, primarily theoretical, work to understand the surprisingly complex physics underlying TDEs. This is a field with important open questions: what are the stellar dynamical processes that feed stars to SMBHs? How do eccentric debris streams from the disrupted star circularize into an accretion disk? What are the emission mechanisms that power the flares we observe? I will propose answers to each of these puzzles, and highlight upcoming observational tests that may answer them decisively. Although the current observational sample of TDEs is modest, upcoming time domain surveys such as ZTF, eROSITA, and LSST will increase our sample size by orders of magnitude. Resolving the theoretical questions I will discuss in this colloquium is the critical step toward using these flares as unparalleled probes of SMBH demography.
Fri, September 29 4:00pm
JILA Auditorium
Phys Chem/Chem Phys Seminar
Jon Abbatt, University of Toronto

Jon Abbatt,
University of Toronto

Abstract/Details

TBA
Sat, September 30 9:30am
Cristol Chemistry Room 140
CU Wizards Program
Go With the Flow!

Janet deGrazia,
University of Colorado
Mon, October 02 4:00pm
JILA Auditorium
Astrophysical & Planetary Sciences Seminar
TBA

Emily Rauscher,
University of Michigan
Mon, October 09 4:00pm
JILA Auditorium
Astrophysical & Planetary Sciences Seminar
The Origin of Supermassive Black Holes

Amy Reines,
Montana State University

Abstract/Details

The origin of supermassive black holes remains a major outstanding issue in modern astrophysics. These monster black holes reside in the nuclei of essentially every massive galaxy and power the most luminous quasars at the edge of the observable Universe. However, directly observing the first “seed” black holes in the early Universe - that can eventually grow to upwards of a billion solar masses - is not feasible with current telescopes. Present-day dwarf galaxies, on the other hand, are within observational reach and offer another avenue to learn about black hole seeds since low-mass galaxies can host relatively pristine black holes. In this talk, I will highlight some of my recent achievements in this field that have taken us from a few rare examples to large systematically assembled samples of dwarf galaxies hosting nuclear black holes. I will also discuss how my work has implications for directly detecting black hole activity in the first galaxies at high redshift.  
Fri, October 13 4:00pm
JILA Auditorium
Phys Chem/Chem Phys Seminar
David Beratan, Duke University

David Beratan,
Duke University

Abstract/Details

TBA
Mon, October 16 4:00pm
JILA Auditorium
Astrophysical & Planetary Sciences Seminar
TBA

Lindsay Glesener,
University of Minnesota
Wed, October 18 4:00pm
Duane Physics Room G1B20
Physics Department Colloquium
TBA

Gilbert Nathanson,
University of Wisconsin, Madison
Fri, October 20 4:00pm
JILA Auditorium
Phys Chem/Chem Phys Seminar
Gustavo Scusseria, Rice University

Gustavo Scusseria,
Rice University

Abstract/Details

TBA
Mon, October 23 4:00pm
JILA Auditorium
Astrophysical & Planetary Sciences Seminar
TBA

Alex Parker,
Southwest Research Institute

Abstract/Details

TBA
Sat, October 28 9:30am
Old Main Chapel
CU Wizards Program
A Visit with Madame Cure; Special 150th Anniversary of Curie's Birth!

Susan Marie Frontczak,
Master Storyteller
Mon, October 30 4:00pm
JILA Auditorium
Astrophysical & Planetary Sciences Seminar
Jorge Moreno, Pomona College

Jorge Moreno,
Pomona College

Abstract/Details

TBA
Fri, November 03 4:00pm
JILA Auditorium
Phys Chem/Chem Phys Seminar
Kit Bowen, Johns Hopkins University

Kit Bowen,
Johns Hopkins University

Abstract/Details

TBA
Mon, November 06 4:00pm
JILA Auditorium
Astrophysical & Planetary Sciences Seminar
Characterizing the Environments of Habitable Exoplanets

Kevin France,
University of Colorado - APS
Fri, November 10 4:00pm
JILA Auditorium
Phys Chem/Chem Phys Seminar
Christine Keating, Penn State

Christine Keating,
Penn State

Abstract/Details

TBA
Mon, November 13 4:00pm
JILA Auditorium
Astrophysical & Planetary Sciences Seminar
A First Characterization of Tidal Disruption Events and Their Surprising Properties

Iair Arcavi ,
University of California, Santa Barbara

Abstract/Details

The search for the tidal disruptions of stars by supermassive black holes (tidal disruption events; TDEs) is now yielding exciting results. In recent years, both gamma- and x-ray candidates as well as optical+UV events have been discovered, and a tantalizing connection to extreme coronal light emitters has been made. It is still not clear what the connection between these very different types of TDE candidates is, but recently we were able to tie several of the optical+UV events together into a coherent class of outbursts. This picture immediately offered two new insights. First, TDE emission properties are not as expected - our set of objects which all peak in the near UV rather than the expected x-rays, show lower than expected velocities and span an unexplained continuum of spectral classes from H-rich to H-poor. The second insight relates to the host galaxies - optical+UV TDEs show a strong (200x!) and unexpected preference for post-starburst galaxies. The reason for this is still not clear. We are collecting more and more observations of TDEs as they are discovered by wide field transient surveys and by our own first- ever specialized survey for TDEs. Understanding TDE emission properties and their peculiar host galaxy preference has far reaching implications for studying quiescent massive black holes, accretion physics and galaxy dynamics.
Sat, November 18 9:30am
Cristol Chemistry Room 140
CU Wizards Program
Immunity in Health & Disease: Superheros Within

Moni Fleshner,
University of Colorado
Mon, November 27 4:00pm
JILA Auditorium
Astrophysical & Planetary Sciences Seminar
The Relevance of Astronomy to the Earth Sciences

Robert Anderson,
University of Colorado, Boulder
Thu, November 30 12:00pm
Duane Physics Room G126
Condensed Matter Seminar
TBA

Sergej Moroz,
Technical University Munich
Sat, December 02 9:30am
CU Planetarium
CU Wizards Program
Rocks on Mars!

Brian Hynek,
University of Colorado
Mon, December 04 4:00pm
JILA Auditorium
Astrophysical & Planetary Sciences Seminar
TBA

Mark Rast,
University of Colorado, Boulder
Thu, December 07 12:00pm
Duane Physics Room G126
Condensed Matter Seminar
TBA

Andrei Bernevig,
Princeton University
Fri, December 08 4:00pm
JILA Auditorium
Phys Chem/Chem Phys Seminar
William Tisdale, MIT

William Tisdale,
MIT

Abstract/Details

TBA
Sun, December 10 4:00pm
JILA Auditorium
Astrophysical & Planetary Sciences Seminar
TBA

Beth Willman,
University of Arizona
Mon, December 11 4:00pm
JILA Auditorium
Astrophysical & Planetary Sciences Seminar
TBA

Beth Willman,
University of Arizona, /LSST

Abstract/Details

TBA
Sat, January 27 9:30am
Duane Physics Room G1B30
CU Wizards Program
Speed!

Eric Cornell,
JILA, University of Colorado
Mon, January 29 4:00pm
JILA Auditorium
Astrophysical & Planetary Sciences Seminar
TBA

Wen-fai Fong,
University of Arizona
Sat, February 24 9:30am
Cristol Chemistry Room 140
CU Wizards Program
The Chemistry of Cooking!

David Nesbitt,
JILA, University of Colorado
Mon, March 05 4:00pm
JILA Auditorium
Astrophysical & Planetary Sciences Seminar
TBA

Nate Kaib,
University of Oklahoma
Sat, March 17 9:30am
Duane Physics Room G1B30
CU Wizards Program
Much Ado About Absolute Zero!

Paul Beale,
University of Colorado
Mon, March 19 4:00pm
JILA Auditorium
Astrophysical & Planetary Sciences Seminar
TBA

John Wisniewski,
University of Oklahoma
Mon, April 02 4:00pm
JILA Auditorium
Astrophysical & Planetary Sciences Seminar
TBA

Shelley Wright,
University of California, San Diego
Mon, April 16 4:00pm
JILA Auditorium
Astrophysical & Planetary Sciences Seminar
TBA

Quinn Konopacky,
University of California, San Diego
Mon, April 23 4:00pm
JILA Auditorium
Astrophysical & Planetary Sciences Seminar
TBA

Daryl Haggard,
McGill University
Sat, April 28 9:30am
Cristol Chemistry Room 140
CU Wizards Program
Sink or Swim!

Mathias Weber,
JILA, University of Colorado
Mon, April 30 4:00pm
JILA Auditorium
Astrophysical & Planetary Sciences Seminar
TBA

Rebekah Dawson,
Penn State
Sat, May 12 9:30am
Duane Physics Room G1B30
CU Wizards Program
The Physics of The Game of Thrones!

Rebecca Thompson,
University of Colorado
Sat, June 16 9:30am
CU Planetarium
CU Wizards Program
Blackholes!

Andrew Hamilton,
JILA, University of Colorado

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