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