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CORNISH WORKSHOP 
 Leeds, 13 th April 2007 James Green

MMB. CORNISH WORKSHOP 
 Leeds, 13 th April 2007 James Green. The Methanol Multibeam Project. The Methanol Multibeam Project: The Team.

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CORNISH WORKSHOP 
 Leeds, 13 th April 2007 James Green

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  1. MMB CORNISH WORKSHOP 
Leeds, 13th April 2007James Green The Methanol Multibeam Project

  2. The Methanol Multibeam Project:The Team R. J. Cohen, J. L. Caswell, K. Brooks, M. G. Burton, A. Chrysostomou, P. J. Diamond, S. Ellingsen, G. A. Fuller, M. D. Gray, J. A. Green, M. G. Hoare, M. R. W. Masheder, N. McClure-Griffiths, M. Pestalozzi, C. Phillips, L. Quinn, M. Thompson, M. Voronkov, A. Walsh, D. Ward-Thompson, D. Wong-McSweeney, J. A. Yates.

  3. Participants

  4. The 6.7 GHz Methanol Maser

  5. Why MMB? - Previous Surveys

  6. MMB 7-Beam Receiver • Jointly built by Jodrell Bank and ATNF. • Hexagonal layout pattern of 7 equal receivers. • Capable of dual polarisation over a large bandwidth. • Calibration with noise injection sampled at 500Hz.

  7. Survey Characteristics I • 4 MHz Bandwidth (180 km/s at 6668 MHz). • Assume 150km/s fully useful bandwidth, so multiple centre velocities toward Galactic centre 10km/s overlap. • Doppler tracking provided by the first two local oscillators. • Correlator configured to provide 2048 frequency channels across each 4 MHz band, at each line frequency and each polarization. • Velocity resolution 0.09 km/s at 6668 MHz. • Spectra dumped every 5 seconds. • System noise temperatures ~20 K.

  8. Survey Characteristics II • HPBW 3.2 arcmin at 6668 MHz and 3.4 arcmin at 6035 MHz. • Beams spaced by 6.46 arcmin on sky. • Multibeam footprint is 15arcmin across. • SPOT and MX observations to monitor variation in calibration. • Blocks of 2O in l, ±2O in b. • Continuous scanning at 0.1O min-1. • Optimal Orientation. • Beam Sensitivity consistent to ±3.5%.

  9. Results: An Example Field OBSERVATIONS LIVEDATA GRIDZILLA KVIS/RESULTS

  10. Survey Progress • Surveyed 106 degrees galactic longitude. • Observed 528 masers, of which 218 new. • 53/100 days Parkes observing time. • Most new are weak (Speak < 4 Jy). • Narrow linewidths (FWHM < 0.2 km/s). • Far-side outer Galaxy detections.

  11. Observations - regions surveyed (0/360) (90) (270) (180)

  12. Observational Distribution l vs b 0 l vs Velocity (LSR)

  13. Survey Statistics - Galactocentric distances

  14. Survey Statistics - Flux distribution Arecibo MMB

  15. Excited OH ResultsL.Quinn • Work in progress..

  16. ATCA & MERLIN • Positioning follow-up: Parkes positions accurate to ± 30 arcsec. • Capabilities to do it in both hemispheres with ATCA and MERLIN: • ATCA ± 0.1 arcsec • MERLIN ± 0.01 arcsec • ATCA observed and positioned all new detections. • MERLIN observed ~30 new in 20-30 region, positioned 25.

  17. MERLIN Follow-up ExamplesD. Wong-McSweeney

  18. Pulsar Survey Piggyback • Deep integrations through pointed observations conducted as part of the pulsar search program. • No Doppler tracking. • Just Methanol 6668 MHz frequency. • Correlator configured for 8 MHz over 4096 channels for 7 beams, 2 polarizations. • Same spectral resolution, but over wider velocity range. • Focused on Galactic Centre, but covering -60 < l < +45 (maximum +/- 0.5 in b).

  19. Magellanic Clouds • Slightly different technique. • Pointed MX observations as well. • 1 new Methanol & 1 new excited OH.

  20. The Work Plan : 2007-2011 • Parkes Multibeam survey till 2008. • ATCA positions, snapshots and 8.4 GHz continuum. • MERLIN positions and snapshots. • Distances and Galactic Distribution. • Jodrell Bank Multibeam survey 2008-2010. • MMB catalogue of Milky Way. • MMB survey of LMC/SMC. • Simultaneous survey of excited OH 6035 MHz. • Methanol deep fields at Pulsar pointings.

  21. MMB-CORNISH Overlap

  22. MMB-CORNISH COINCIDENCES

  23. MMB-CORNISH COINCIDENCES

  24. MMB-CORNISH COINCIDENCES

  25. MMB-CORNISH COINCIDENCES 1.1 Jy 8 Jy 4 Jy 0.8 Jy 2.6 Jy 3 Jy 2.6 Jy 7.5 Jy

  26. Conclusion • MMB first full Galactic plane survey. • 528 detections & counting • MMB-CORNISH overlap looks very promising.

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