Edward's homepage at UBC

Dr. Edward Chapin
Dept. of Physics & Astronomy
6224 Agricultural Road
Vancouver, BC, V6T 1Z1, Canada
Ph: +1 604.602.2382

curriculum vitae

Research

Ed in Antarctica with BLAST
I am an observational astrophysicist who works primarily with data taken in the submillimetre (submm) part of the spectrum (wavelengths spanning roughly 100 -- 1000 um). Under the right conditions, clouds containing both dust and molecular gas collapse and form stars. The instant at which stars "turn-on" is generally invisible at optical wavelengths since the dense material from which they form is optically thick. However, the absorbed light heats dust to temperatures of several 10s of Kelvin, at which point their thermal emission is clearly visibile at submm wavelengths. For this reason these types of observations are crucial for understanding the earliest stages of star-formation. Similarly, at vast cosmological distances, young massive galaxies forming many stars (100s to 1000s per year, compared with a few per year in the Milky Way) produce bright submm emission while the optical emission can be extremely faint. Submm observations are therefore crucial to our understanding of how the largest galaxies formed and evolved after the Big Bang.

These are the main projects I am currently involved with:

SCUBA-2

The Submillimetre Common-User Bolometer Array 2 (SCUBA-2) is currently the world's largest, and most efficient ground-based submm camera, mounted on the 15-m James Clerk Maxwell Telescope in Hawai'i. I am a member of the data reduction software team and am leading the development of the iterative map-maker. I am very busy these days helping out with commissioning. Once that is done, I will be particularly involved in the analysis of images from the Cosmology Legacy Survey, and SCUBA-2 "All-Sky" Survey.

BLAST

The Balloon-borne Large-Aperture Sub-millimetre Telescope (BLAST) is a 2-m telescope that is suspended from a high-altitude (~35 km) balloon platform. The BLAST camera is a SPIRE prototype, observing simultaneously at 250, 350 and 500 um. I was a member of the team that built the telescope, made significant contributions to the pointing system, and coordinated the observing schedules for the 2005 and 2006 long-duration science flights from northern Sweden, and Antarctica (pictured above), respectively. For further details, including public data products and publications, see the BLAST public web page.

Herschel

Following on from my work on BLAST, I am now participating in the analysis of data from the Herschel satellite (BLAST's bigger 3.5-m sibling) taken as part of HerMES. Mostly I am involved in extending the techniques I developed for BLAST source identification to the deeper / higher-resolution images produced by SPIRE.

IDL software for source identification

I have worked on a number of algorithms that are useful for finding bumps in submillimetre maps, and performing cross-identifications with external catalogues. The two things that most people will probably be interested in is the matched filter (useful for mildly de-convolving the beam from confusion-limited SPIRE maps), and the likelihood ratio code for identifying counterparts. I have been slowly cleaning up this code to make it useful to other people. Documentation is sorely lacking, but I will attempt to change that in the near future. For now, if you wish to experiment, you can obtain the software from a public archive hosted at http://github.com. The comments for the routines are fairly verbose. The following incantation will check out a copy (assuming you have git installed on your computer):

git clone git://github.com/edwardchapin/submm_idl.git

If you can't wait for documentation and want some help, feel free to e-mail me. If you would like to collaborate and/or add new features, also let me know!

Selected recent publications

1. Marsden G., Chapin E.L., Halpern H., Patanchon G., Scott D., Truch M.D.P., Valiante E., Viero M.P., Wiebe D.V., 2011, MNRAS, accepted: A Monte Carlo Approach to Evolution of the Far-Infrared Luminosity Function with BLAST

2. Chapin E.L., Chapman S.C., Coppin K.E., Devlin M.J., Dunlop D.S. et al., 2011, MNRAS, 411, 505: A joint analysis of BLAST 250-500um and LABOCA 870um observations in the Extended Chandra Deep Field-South

3. Chapin E.L., Pope A., Scott D., Aretxaga I., Austermann J. et al., 2009, MNRAS, 398, 1793: An AzTEC 1.1mm survey of the GOODS-N field - II. Multiwavelength identifications and redshift distribution

4. Devlin M.J., Ade P.A.R., Aretxaga I., Bock J.J., Chapin E.L. et al., 2009, Nature, 458, 737: Over half of the far-infrared background light comes from galaxies at z>=1.2

5. Chapin E.L., Hughes D.H., Aretxaga I., 2009, MNRAS, 393, 653: The local far-infrared galaxy colour-luminosity distribution: a reference for BLAST and Herschel/SPIRE submillimetre surveys

6. Perera T.A., Chapin E.L., Austermann J.E., Scott K.S., Wilson G.W. et al., 2008, MNRAS, 391, 1227: An AzTEC 1.1mm survey of the GOODS-N field - I. Maps, catalogue and source statistics

7.Chapin E.L., Ade P.A.R., Bock J.J., Brunt C., Devlin M.J. et al., 2008, ApJ, 681, 428: The Balloon-borne Large Aperture Submillimeter Telescope (BLAST) 2005: A 4 deg^2 Galactic Plane Survey in Vulpecula (l = 59 deg)

8.Coppin K., Chapin E.L., Mortier A.M.J., Scott S.E., Borys C. et al., 2006, MNRAS, 372, 1621: The SCUBA Half-Degree Extragalactic Survey - II. Submillimetre maps, catalogue and number counts