1 / 14

The JCMT in the ALMA Era

The JCMT in the ALMA Era. Surveying the Sub-millimetre Sky (Canada / Netherlands / Great Britain). Doug Johnstone NRC/HIA. A New Suite of Instruments. Faster bolometer array (SCUBA2) Continuum mapping at multiple wavelengths Ancillary devices (polarimeter, FTS)

belle
Download Presentation

The JCMT in the ALMA Era

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The JCMT in the ALMA Era Surveying the Sub-millimetre Sky (Canada / Netherlands / Great Britain) Doug Johnstone NRC/HIA

  2. A New Suite of Instruments • Faster bolometer array (SCUBA2) • Continuum mapping at multiple wavelengths • Ancillary devices (polarimeter, FTS) • Magnetic fields, line- and SED-fitting • Heterodyne Receiver Array (HARP-B) • 16 receivers @350 GHz (CO 3-2 etc) • Submillimetre array (eSMA)

  3. SCUBA2The Future of Sub-Millimetre Mapping • >100 times faster than present instruments • Survey large regions of the sky quickly • Square degrees per hour • Survey to the point-source confusion limit • Allow for ‘complete’ source counts • Finding chart for ALMA • Beam size 15", centroid to a few arcseconds

  4. Focal plane layout ~8 arcmin (~100mm) SCUBA2 Key Features • A large 7x7 arcminute field-of-view • Fully sampled - Nyquist at 850m • Sensitivity governed by the sky background • Simultaneous imaging at 850m & 450m • No chopping required • Greater sensitivity to large-scale structure

  5. Estimated performance m m 450 m 850 m Parameter SCUBA SCUBA-2 SCUBA SCUBA-2 Per-pixel NEFD 400 75 90 32 Ö (mJy/ Hz) Point-source NEFD 400 107 90 22 Ö (mJy/ Hz) Point source flux 1 10 1 12 Extraction speed Large area mapping 1 810 1 980 speed

  6. JCMT/SCUBA-2 (450m) 7 arcsec resolution : 64 arcmin2 field-of-view (simulation by Governato et al.) Herschel/SPIRE (350m) 25 arcsec : 16 arcmin2 (simulation by Hughes & Gaztanaga) JCMT/SCUBA (850m) 14 arcsec : 5 arcmin2 (HDF image from Hughes et al. 1998) Compact ALMA (450m) 0.01 arcsec : 0.02 arcmin2 Large-scale surveys SCUBA-2 will map large areas of sky at least 10 times faster than ALMA to the same S/N...

  7. Deep extragalactic surveys A 50-hr observation with SCUBA Deep imaging? It would take SCUBA-2 ~50 hours to map 1 deg2 area of sky to the confusion limit (0.5 mJy) at 850m

  8. Wide-field Galactic surveys SCUBA Galactic Centre Survey ~15 shifts (or 120 hrs) of telescope time Galactic Plane SCUBA-2 could map the entire area shown left in just a couple of hours to the same S/N... Full moon All sky survey? It would take SCUBA-2 ~500 hours to map the entire Mauna Kea sky to the depth of the SCUBA Galactic Centre image

  9. Ophiuchus – JCMT 2003 In 2003 observed 4 sq. degrees to 40 mJy/bm as part of the COMPLETE Project. Took 40 hours! Largest SCUBA map to date Expect 100’s of new compact sources Found only 2!

  10. Ancillary Instruments • Polarimeter • Measure polarized emission and orientation • Importance of magnetic fields (especially in regions of star formation) • Study the properties of dust • Fourier Transform Spectrometer • Moderate-resolution spectrum • Quickly obtain strong emission lines (e.g. CO) • Hot core diagnostics • Low-resolution spectrum • SED shape - temperature and dust emissivity

  11. Polarimetry of the Orion Ridge

  12. When and How? • SCUBA2 on the telescope by end of 2005 • Full functionality in 2006 • Legacy Surveys being determined NOW! • Likely 50% of telescope time • Still time to forward ideas to JCMT members • Tri-Partate agreement for JCMT expires 2009 • Future of the JCMT beyond 2009 open to ideas • There will still be a great deal of sky to map! • Partenership Opportunities

  13. Canadian SCUBA-2 Consortium SCUBA-2 Website: http://www.roe.ac.uk/ukatc/projects/scubatwo

More Related