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VLBA Imaging and Polarimetry Survey

VLBA Imaging and Polarimetry Survey. Greg Taylor (UNM) The Future of the VLBA – Charlottesville, VA Jan. 28, 2011. VIPS - V LBI I maging and P olarimetry S urvey. The VIPS team is: Greg Taylor (UNM/NRAO), Chris Fassnacht (UCD), Joe Helmboldt (UNM), Larry Weintraub (Caltech)

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VLBA Imaging and Polarimetry Survey

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  1. VLBA Imaging and Polarimetry Survey Greg Taylor (UNM) The Future of the VLBA – Charlottesville, VA Jan. 28, 2011

  2. VIPS - VLBI Imaging and Polarimetry Survey The VIPS team is: Greg Taylor (UNM/NRAO), Chris Fassnacht (UCD), Joe Helmboldt (UNM), Larry Weintraub (Caltech) Jim Ulvestad (NRAO), Craig Walker (NRAO), Steve Myers (NRAO), Lorant Sjouwerman (NRAO), Tim Pearson (Caltech), Tony Readhead (Caltech), Neil Gehrels (NASA GSFC), Roger Romani (Stanford), Peter Michelson (Stanford), Roger Blandford (KIPAC) PhD Students: Steve Tremblay (UNM) anticipated 2011 Justin Linford (UNM) anticipated 2012

  3. VIPS and Fermi • VLBA Imaging Polarimetry Survey (VIPS) • 1127 sources: S > 85 mJy, dec > 20, |b|>10 at 8 GHz • in SDSS northern cap • First epoch observations during 200+ hours on VLBA in 2006 (~$30K Funding from Stanford/UNM for disks) • Identifications and redshifts from SLOAN, HET, Palomar, … • Goals: • - Characterize Fermi sources • - Understand polarization properties of AGN classes • - Study AGN environments • - Find close binary black hole systems http://www.phys.unm.edu/~gbtaylor/VIPS/

  4. VIPS on the web 1127 in sample 11 not detected 169 previously imaged ------ 947 newly imaged http://www.phys.unm.edu/~gbtaylor/VIPS/

  5. Publications • Taylor et al. 2005, ApJS, "An Automated approach... • Helmboldt et al. 2007, ApJ, "VIPS at 5 GHz" • Taylor et al. 2007, ApJ, "Characteristics of EGRET ... • Tremblay et al. 2008, ApJ, "A Shrinking CSO ... • Helmboldt et al. 2008, ApJ, "A statistical description... • Tremblay et al. 2009, ApJ, "Identifying CSOs ... • Linford et al. 2011, ApJ, "Characteristics of Fermi ... + 7 more by the VIPS collaboration >12 more by others

  6. VIPS CSO Candidates • Follow-up Observations • 5, 8, 15 GHz VLBA • Full polarization • Spectral classification: • F • Kinematic Analysis • Ages/Dynamics • Polarization Analysis • Evolution of Radio Galaxies 20 pc Tremblay et al in prep.

  7. Age Estimates Gugliucci et al. 2005 Tremblay et al in prep.

  8. Core Brightness Temperatures • LAT core TBs tend to be higher than non-LAT. Except BL Lacs. • Kolmogorov-Smirnov (K-S) tests indicate that the FSRQs are very different, but BL Lacs are similar. Stacked histograms Top: LAT Bottom: non-LAT Linford et al.

  9. Core Polarization • The percentage of sources found to be polarized is higher for LAT blazars than for non-LAT blazars.

  10. C1: 0.183 ± 0.048 pc C2: 0.124 ± 0.035 pc Projected separation between C1 and C2 equal to 7.3 pc CJF 0402+379 – A Compact Binary Black Hole Radio Continuum Rodriguez et al. astro-ph/0604042 Naturally weighted 2005 VLBA imagesof 0402+379 at 0.3, 5, 8, 15, 22, and 43 GHz.

  11. J16325+3547

  12. J17246+6055

  13. Thoughts about the Future Don't sacrifice the User community • They contribute ideas, effort and (sometimes) funds • Maintain time for Users on the VLBA • Maintain 10 antennas if at all possible Future plans • Take advantage of bandwidth expansion to do polarimetry of gamma-ray blazars (RM Synthesis) • Contemporaneous VLBA observations with Fermi • Study CSO Motions, spectra, Faraday RMs, ages • Use new correlator to survey 10,000+ sources for SBBHs • Difficult to do above with < 9 antennas (reduced spatial dynamic range, fidelity)

  14. Backup Slides

  15. Radio Target List • Selection S4.8>65mJy, |b|>100, a<0.5 -- CLASS+ • 11,131 sources - Healey et al. 2007 • Attempts to fill in PMN holes w/ S5, lower n-selected sources • Combined Radio All-sky Targetted Eight-GHz Survey: CRATES

  16. Sky Coverage

  17. VIPS 5 GHz Summary of Source Types in VIPS Type N Npol/N PS 276 31+/- 4% SJET 241 36 +/- 5% LJET 471 41 +/- 4% CSO 103 15 +/- 4% CPLX 17 11 +/- 8% ND 11 …

  18. At their base, Jets tend to have magnetic fields aligned with the jet axis. Helmboldt et al. 2007 This trend should become more pronounced once we can correct for Faraday rotation

  19. Which one of these Jets will be detected by GLAST? Helmboldt et al. 2007

  20. Manpower Estimates First epoch 5 GHz - Kept up • 2 x 10 hours each month for 10 months • 50% of Joe H., 10% of Greg, 5% Lorant SBBH 5, 8, 15 GHz - not keeping up • 3 x 17 hours in the past 3 months • 50% of Steve T., 10% of Greg • Reduction is more complicated Proposed Multi-epoch follow-up (20 h/month) • 1.5 FTE, 10% of Greg, 5% Lorant

  21. CJF 0402+379 In both hotspots of the source, N2 and S2, a steep spectrum was found. For both central components, C1 and C2, the spectrum peaks at ~10 GHz. Spectral index distribution between 8 and22 GHz from the 2005 VLBA observations.

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