Date

Speaker

Title

Aug 30

Neal Evans

University of Texas at Austin

Organizational meeting.

Sep 6

Joel Green

University of Texas at Austin

"Episodic Accretion in Young Stars"

In the last twenty years, the topic of episodic accretion has gained significant interest in the star formation community. It is now viewed as a common, though still poorly understood, phenomenon in low-mass star formation. The FU Orionis objects (FUor) are long-studied examples of this phenomenon. FUors are believed to undergo accretion outbursts during which the accretion rate rapidly increases from typically 10^-7 to a few 10^-4 M(solar) yr^-1, and remains elevated over several decades or more. EXors, a loosely defined class of pre-main sequence stars, exhibit shorter and repetitive outbursts, associated with lower accretion rates. The relationship between the two classes, and their connection to the standard pre-main sequence evolutionary sequence, is an open question: do they form two distinct classes, are they triggered by the same physical mechanism, and do they occur in the same evolutionary phases? Over the past couple of decades, many theoretical and numerical models have been developed to explain the origin of FUor and EXor outbursts. In parallel, such accretion bursts have been detected at increasing rate, and each individual outburst is more carefully scrutinized and monitored across the electromagnetic spectrum. We summarize key observations of pre-main sequence star outbursts, and review the latest thinking on outburst triggering mechanisms, the propagation of outbursts from star/disk to disk/jet systems, the relation between classical EXors and FUors, and newly discovered outbursting sources - all of which shed new light on episodic accretion. We finally highlight the most promising directions for this field in the near- and long-term.

close

Sep 13

Charles "Chat" Hull

University of California, Berkeley

"From Clouds to Cores to Envelopes to Disks: A Multi-scale View of Magnetized Star Formation" (host: Joel Green)

abstract

Sep 20

Mike Pavel

University of Texas at Austin

"Polarimetric Tomography of the Galactic Magnetic Field"

Sep 27

Adam Kraus, Joel Green, Michael Gully-Santiago, Neal Evans

University of Texas at Austin

"Highlights from the Protostars & Planets VI Conference (Heidelberg, Germany: 15-20 July 2013)"

Oct 4

Vanessa Bailey

University of Arizona

(host: Neal Evans) "Hole-y Debris Disks, Batman! (Giant planets sculpting disks and the technology we need to image them)"

abstract

Oct 11

No talk scheduled, to avoid conflict with the Bashfest 2013 Symposium (on 7-8 October).

Oct 18

Megan Reiter

University of Arizona

"Jets from Intermediate-mass Protostars as a Fossil Record of Accretion"

abstract

Oct 18

Johanna Teske

University of Arizona

"Diamonds in the Rough: A Cautionary Tale of C/O Ratios in Exoplanet Host Stars"

abstract

Oct 25

Yao-Lun Yang

University of Texas at Austin

"Molecular Hydrogen in the Diffuse Medium of the Large Magellanic Cloud"

Nov 1

"NRAO Community Day: NRAO Data Analysis Workshop (8 AM - 6 PM: POB 2.302 Avaya Auditorium)

Nov 8

Jeong-Eun Lee

Kyung Hee University, South Korea

"Detailed Analysis of DIGIT Embedded Protostars"

abstract

Nov 15

Presentations by Manuel Merello and Emma Yu have been rescheduled to next week (22 November).

Nov 22

Manuel Merello

University of Texas at Austin

"Physical Characterization of Galactic Star-forming Clumps using (Sub)millimeter Continuum Surveys"

Nov 22

Emma Yu

University of Texas at Austin

"Probing the Protoplanetary Disks with ALMA - a CO Perspective"

Nov 29

Day after Thanksgiving Day: Staff Holiday. University Closed: No classes or seminars held today.

Dec 6

Harriet Dinerstein

University of Texas at Austin

"Kappa Distributions: A Possible Solution to the Nebular Abundance Problem"

Dec 6

Amanda Turbyfill

University of Texas at Austin

"Application of Kappa Distributions to Planetary Nebulae Spectra"