Astronomy & Physics

Astronomy & Physics



The masses of galaxies as determined from model fits to resolved images (used here as plotting points) compared to fits using unresolved (i.e., single pixel) images depends on the rate of star formation in the galaxy.

Ph.D. graduate student Bobby Sorba and Professor Sawicki improve mass estimates of galaxies.

Sorba and Dr. Sawicki's recent research paper (to be published in the Monthly Notices of the Royal Astronomical Society) shows that model fits to resolved images of galaxies produce similar mass estimates to model fits to unresloved images for galaxies but only for galaxies that have lower rates of internal star fromation. As the star formation rates increase, the masses derived from unresolved model fits are lower (presumably underestimated) compared to the model fits to the resolved images. Indeed, as they show in the figure above the trend is linear. Astronomers can can continue to estimate the masses of galaxies using unresolved images (necessary for faint galaxies such as high red shift galaxies) and then apply a simple correction to improve the mass estimate. 

A Postdoctoral Research Fellow position in experimental nuclear physics, at TRIUMF, Canada with Professor Rituparna Kanungo is available. For more information: IRIS_Postdoc_2015

Tier I Canada Research Chair - Astronomy. The Saint Mary's University Department of Astronomy and Physics invites applications from researchers in any area of astronomy and astrophysics to be the University’s nominee for our Tier I Canada Research Chair (CRC) in Astronomy. Contact Prof. Rob Thacker for more information. Click here for more details.

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Liz Arcilia-Osejo_TN
July 30, 2015
Dead Galaxies
PhD candidate Liz Arcilia-Osejo is interviewed on CTV's Live at 5 about her research on dead galaxies.

ASTRO-H X-ray telescope
June 15, 2015
Prof. Gallo leads Astro-H
Prof. Gallo leads Canadian contribution to X-ray telescope.

Father Lonc
November 27, 2014
In Memoriam of Dr William Lonc
Fr. Dr. William P. Lonc, S.J. died on November 27, 2014; he was 84 years old.

Logan Francis
December 1, 2014
Best Undergraduate Science Paper
Logan Francis wins award for science project on physical random number generators.

New BGO Telescope with Mann
October 29, 2014
New Telescope
New 0.6m Medjuck Telescope unveiled at Burke-Gaffney Observatory.
August 31, 2015, SB 255
How to Publish a Paper in Nature
Dr. Leslie Sage (University of Maryland; Nature)

September 11, 2015, AT 101
Undergraduate Research Symposium
Summer undergraduate research symposium

September 16, 2015, TBA
The faintest galaxies as probes of cosmology and galactic evolution
Dr. Michelle Collins (Yale University)

October 9, 2015, TBA
Dr. Kim Venn (University of Victoria)