The JCMT Legacy Survey

Transcription

1 The JCMT Legacy Survey Surveying the Milky Way in the Submillimetre Antonio Chrysostomou (JAC) and the JCMT Legacy Survey teams

2 Outline Quick Introduction of JCMT and its instrumentation HARP/ACSIS SCUBA-2 JCMT Legacy Surveys quick introduction recent results from surveys in Milky Way currently running brief descriptions of future surveys of the Milky Way

3 Introduction JCMT Partnership United Kingdom: 55% Canada: 25% Netherlands: 20% All partners have expressed their commitment to continue operations until at least 2012 Telescope Diameter: 15 m largest single dish telescope dedicated to submillimetre astronomy Surface: 22 µm Instrument Suite covers a variety of observing modes and techniques imaging - spectroscopy - polarimetry - FTS Over recent years, JCMT has undergone a transformation to its next generation of instrumentation at a cost of ~ $35M Operating wavelengths 200 µm through to 3 mm

4 Introduction HARP/ACSIS The HARP receiver and ACSIS correlator an imaging spectrometer in 345 GHz band 8192 spectral channels in a 4x4 receptor array

5 Introduction HARP/ACSIS The HARP receiver and ACSIS correlator an imaging spectrometer in 345 GHz band 8192 spectral channels in a 4x4 receptor array Orion Molecular Cloud blue velocities (courtesy HARP commissioning team) red velocities

6 Introduction SCUBA-2 We expect SCUBA-2 to make a significant impact on submillimetre astronomy simultaneous imaging at 850 µm and 450 µm with large field of view (> 50 sq. arcmin) 14- and 8-arcsec resolution four TES 40x32 pixel arrays at each wavelength More than 10,000 pixels SCUBA-2 will map the submillimetre sky ~1000 times faster than SCUBA

7 Introduction SCUBA-2 Galactic Plane Full moon SCUBA map took 120 hours SCUBA-2 will map the entire area shown to same depth in a couple of hours!!

8 Introduction SCUBA-2 Early commissioning results a 10 x10 scan of the Orion Molecular Cloud at 450 µm observed with commissioning grade arrays poor sensitivity & yield but good enough for integration tests total exposure time was 20 minutes with less than 5% of the array pixels contributing to the image!

9 Introduction SCUBA-2 Early commissioning results iterative map maker Raw 5-min image Processed with iterative map maker

10 Introduction SCUBA-2 Early commissioning results comparison with SCUBA at 450 µm 1999: Night-time, excellent weather, 2 nights of data (Johnstone & Bally) 2009: Late afternoon, average weather, 20 minutes exposure, CG arrays

11 JCMT Legacy Survey New instrumentation new capabilities new opportunities In 2006, the JCMT Board approved the JLS 55% of all UK/CA/NL time initial programme amounting to 265 nights* * Review in 2008 added a further 41.5 nights to the HARP programme Seven projects, varied in scope and target but driven by fundamental question of origins formation and evolution of galaxies and the universe formation and evolution of stars, planets and the Milky Way

12 JCMT Legacy Survey Survey SCUBA-2 HARP POL-2 FTS-2 SLS Spectral Legacy Survey DDS Debris Disks Survey GBS Gould Belt Survey JPS JCMT Plane Survey NGS Nearby Galaxies Survey CLS Cosmology Legacy Survey SASSy SCUBA-2 All-Sky Survey 70% of all time awarded to JLS is for SCUBA-2

13 JCMT Legacy Survey Early science results from JLS 12 CO 3-2 Gould Belt Survey to survey all star formation within the Gould Belt, giving a census of low-mass star formation within 500 pc of the Sun explosive star formation in the Serpens molecular cloud Hogerheijde et al (2009)

14 JCMT Legacy Survey Early science results from JLS Gould Belt Survey to survey all star formation within the Gould Belt, giving a census of low-mass star formation within 500 pc of the Sun outflows in Orion A NGC CO C 18 O Buckle et al (2009)

15 JCMT Legacy Survey Early science results from JLS Gould Belt Survey to survey all star formation within the Gould Belt, giving a census of low-mass star formation within 500 pc of the Sun Spectral Legacy Survey to obtain a chemical inventory of star forming environments stratification of molecular species in photodissociation regions Van der Wiel et al (2009) Orion Bar

16 JCMT Legacy Survey Early science results from JLS HCN J=4-3 Gould Belt Survey to survey all star formation within the Gould Belt, giving a census of low-mass star formation within 500 pc of the Sun Spectral Legacy Survey to obtain a chemical inventory of star forming environments the usefulness of HCO + and HCN as tracers of star formation Roberts et al (2009)

17 JCMT Legacy Survey JCMT Plane Survey aim of survey is to achieve a full census of star formation activity in the plane of the Galaxy using SCUBA-2 at 450 µm and 850 µm initial programme to observe inner and outer Galactic regions longitude range: GLIMPSE-North 10 < l (degrees) < 65 FCRAO outer Gal. 102 < l (degrees) < 142 latitude range: b (degrees) = 1 Observe whole plane visible from Mauna Kea after this initial phase is complete

18 JCMT Legacy Survey JCMT Plane Survey 1-sigma = 4 mjy at 850 µm 1 solar mass per beam at 3 kpc 40 solar masses per beam at 20 kpc sensitive to all massive star formation in the Galaxy all unresolved sources detected beyond ~ 3 kpc will be star forming

19 JCMT Legacy Survey SCUBA-2 All-Sky Survey SASSy in this context, All Sky really means All Mauna Kea Sky (δ > 30 ) SASSy is purely a detection experiment and will operate at 850 µm only will observe in poor band 4 weather ( wet ) to minimise impact on other surveys can be used as backup to other survey projects to ensure that there is always some survey data being observed Initial phase: 500 hours GP-wide: 10 wide strip centred on Galactic Plane (l = ) to match UKIDSS and MSX surveys P2P: 10 wide strip through Galactic N & S poles, centred on NEP to cover deepest Planck survey

20 Conclusions Surveys of the Milky Way as part of the JLS have already began with the spectroscopic components using HARP On-sky commissioning with SCUBA-2 is about to begin this autumn (fall) we then plan to ask the JCMT community to become involved in an opportunity for early science with a phase of shared-risks observing Upgrade to full complement of science grade arrays will occur in the new year followed by another phase of on-sky commissioning before the instrument is released for full science & survey operations The next 2-3 years promise to be exciting ones for the JCMT and the JCMT Legacy Surveys of the Milky Way (and beyond)