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The Canadian Galactic Plane Survey
What is the CGPS?
Status and some results
What’s next?
Mapping the Ecology of the Milky Way Galaxy
A Universe of Stars? A Universe of Hydrogen gas
The Evolution of Matter
Increasing radiation wavelength
The Milky Way Galaxy is the only galaxy close enough to see the details of the Galactic “Ecosystem”.
Challenges
The Galaxy is very big. Because we are inside it, it completely encircles the earth. – A large area of sky must be observed.
• The Galaxy is a 3-dimensional object.– Must untangle the third dimension
• High Angular resolution is need to see the details in the context of the larger picture– A very large data base
• A large range of wavelengths must be covered to see all major components of the ISM– Several telescopes are required.
The Canadian Galactic Plane ConsortiumCanadian Universities
• University of Calgary• University of Alberta • University of British Columbia• University of Toronto• University of Montreal• University of Waterloo• Queen’s University• Université Laval
National Research Council of Canada• Dominion Radio Astrophysical Observatory• Canadian Astronomical Data Centre
International Organizations• California Institute of Technology • University of California, Berkeley • University of Massachusetts • University of New Mexico • Space Telescope Science Institute • Cambridge University • Hamburger Sternwarte
The CGPS Data Base
All images at 1 arcminute resolution
Where is the CGPS?
Image compliments of Alan Dyer
The Dominion Radio Astrophysical Observatory
CGPS Data Processing Status (May 10, 2000)
1420 MHz supermosaic of low longitude end
Thanks to Roland Kothes
MM1
MM1: 21 cm
Digital Sky Survey Image
Rotation Measures
Measured from the change in polarisation angle over the four 7.5 MHz continuum bands.
All sources with S > 3 mJy
Approximately 0.5 sources per square degree
(Talk by Jo-Anne Brown)
Milky Way at Radio (21 cm)
Atomic hydrogen gas
Atomic Hydrogen Image from a Single-Antenna Radio Telescope
(one velocity plane in the Perseus Arm)
25-m Radio Telescope, DwingelooNetherlands Foundation for Radio Astronomy
Atomic Hydrogen Image from a Radio Interferometer
7-element Interferometer, PentictonDominion Radio Astrophysical Observatory
equivalent diameter equals 600m
A top-down view of the hydrogen cube
The Perseus spiral arm
The Local spiral arm
Outer spiral arm
Optical Image Stars and Ionized gas
Composite Image Hydrogen Gas Dust Ionized Gas
A 2000 Light-year section of the Perseus Arm.
Image Compliments: J. English and the CGPS
Cold Hydrogen Clouds
Clouds of very cold, dense hydrogen are seen silhouetted against a bright hydrogen gas.
Where did these clouds come from?
Temperature < 50 K
(more details from Steve Gibson)
Molecular Clouds not associated with CO emission
I100 = a NH
NH2 = 0.5 (I/a – NHI)
Predict NH2 from dust andHI emission
Cold HI
CO
(See poster by Kevin Douglas)
Fossils in Hydrogen Gas
Image Compliments: J. English and the CGPS
Ubiquitous HI provides Matrix for ISM “fossils”
Relic shells of Energetic Events
Triggers of star Formation?
Atomic Hydrogen Mushroom Cloud
Radio Multi-band Photometry
CGPS1 and 2
A Global HI Conspiracy
Mapping the HI Milky Way
(CGPS/VGPS/SGPS)
A Global Galactic Plane Survey Dominion Radio Astrophysical ObservatoryNational Research Council of Canada
Australia Telescope Compact Array Commonwealth Science and Industrial Research Organisation
Very Large ArrayU.S. National Radio Astronomy Observatory
Phase I CGPS
SGPS
A Global Survey: CGPS, VGPS and SGPS
VLA – D Array HI Survey of the First Quadrant(VGPS)
Proposal Submitted December 1999
A.R. Taylor, S.J. Gibson (University of Calgary)
J.M. Dickey, N. McClure-Griffiths (University of Minnesota)
B. Gaensler (MIT)
A. Green (University of Sydney)
M. Heyer (University of Massachusetts)
J. Irwin (Queens University)
J. Jackson (Boston University)
T. Landecker, C. Brunt, C. Kerton (HIA)
F. Lockman (NRAO)
P. Martin (CITA)
Northern Hemisphere Coverage
CGPS 2 Longitude ExtensionVGPS (phase I)
FCRAO OGS BU-FCRAO GRS
Onsala CO Survey (proposed)
HI
CO
A Global Galactic Plane HI Survey
Dominion Radio Astrophysical ObservatoryNational Research Council of Canada
Australia Telescope Compact Array Commonwealth Science and Industrial Research Organisation
Very Large ArrayU.S. National Radio Astronomy Observatory