Category Archives: Colloquium

Halloween Potluck

Faculty, staff, and students gathered for a Halloween Potluck on October 25, 2012. The potlucks were inspired some years ago by our super Administrative Assistant Colleen Palleschi. This was her final potluck before her retirement in early January 2013. The students honored her with a framed collection of photos of Physics & Astronomy students throughout her years. For photos of the event see the Photo Gallery.

Faculty and Staff made the food for the luncheon. The menu included:
Chicken & Pumpkin Stew
Turkey & Stuffing
Hot Dogs
Sweet & Sour Beans
Dal
Chicken & Broccoli Stir Fry
Perecca’s Goodies
Apple Scones
Morning Glory Muffins

Physics Summer Research Student Poster Session 2012

Physics and Astronomy summer research students displayed the results of their projects in a poster session on Thursday, Sept. 13.

Colloquium 10/13: A Sound Way to Measure Nanostructures: Ultrafast Optics and Picosecond Ultrasonics

Title: A Sound Way to Measure Nanostructures: Ultrafast Optics and Picosecond Ultrasonics

Speaker: Brian Daly, Vassar College

Abstract: We can take it for granted that progress in nanoscale science and technology in the coming decades will depend heavily on imaging and sensing methods with nanometer resolution. A number of established techniques can provide us with this resolution (e.g. electron microscopy, atomic force microscopy) but these are restricted to objects on or very near the surface of a sample. A wide range of nanostructures are currently under development across the spectrum of the sciences, and in many cases these structures come in the form of multi-layered stacks. As such, a method for the study of buried nanostructures and films is required.

One solution to this problem is to use ultrasound, which has been successful in medical and industrial fields for imaging with optimum resolution in the range of 10′s to 100′s of micrometers. In order to obtain nanometer scale resolution, we must use waves that have a much shorter wavelength (higher frequency) than traditional ultrasound. To do this, we use one of the most versatile tools of the quantum mechanical age, the ultrafast laser. An ultrafast laser produces pulses of light that are shorter than 1 picosecond, and when these pulses are absorbed by a solid layer, they generate extremely high frequency sound waves: what we like to call “Picosecond Ultrasonics.”

In this presentation I will give an overview of the way in which we use light to generate and detect high-frequency ultrasound in solid samples. I will also describe a companion technique for measuring thermal properties of nanoscale films known as Time-Domain Thermoreflectance

As always, lunch will be provided at 12:20 in Room N304, and all are welcome. The full schedule for the Fall term Physics and Astronomy Colloquium Series is here.

Summer Student Poster Session to Kick Off Fall 2011 Colloquium

The Nth Annual Summer Student Poster Session will be held this Thursday, September 15. Students who did summer research projects either on campus or at other institutions will give posters on their work in the halls of the Department of Physics and Astronomy, beginning at 12:20 pm. As always, lunch will be provided at 12:20 in Room N304, and all are welcome to come hear about the exciting activities of our students.

The poster session is also the traditional kick-off for the Fall term Physics and Astronomy Colloquium Series, the full schedule for which is here.

Colloquium 2/17/11: “ALFALFA and the Hunt for Extreme-Mass Galaxies “

Speaker: Ann Martin, Cornell University

Title: ALFALFA and the Hunt for Extreme-Mass Galaxies

Abstract: The ongoing Arecibo Legacy Fast ALFA (ALFALFA) survey is using the Arecibo Observatory to make a census of neutral hydrogen gas in ~ 30,000 nearby galaxies. This method is efficient at finding very low mass, very faint galaxies as well as distant, rare high-mass galaxies. The statistical distributions of gas-rich galaxies in the local Universe will reveal relationships between galaxies’ stellar properties, star formation histories, gas masses, and environment, helping us to untangle galaxy evolution. I will describe ongoing projects that challenge our current understanding of both very small and very large galaxies. I will discuss two statistics, the neutral hydrogen mass function and the correlation function, and how they reflect the cosmological implications of the characteristics of the ALFALFA sample.

As always, the colloquium will be at 12:40 in Room N304, with pizza and soda available at 12:20 for those attending the talk. For details of future colloquia, see the Winter 2011 colloquium schedule.