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Radio Astronomy -- Other Than ALFA Surveys

Chris Salter (NAIC/Arecibo Observatory). Radio Astronomy -- Other Than ALFA Surveys. 430-MHz Arecibo + DRAO-ST image of a region of the Perseus-Pisces Supercluster. (Courtesy: Phil Kronberg). The Rules of the Game. Pre-Nov 2006 :

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Radio Astronomy -- Other Than ALFA Surveys

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  1. Chris Salter (NAIC/Arecibo Observatory) Radio Astronomy -- Other Than ALFA Surveys 430-MHz Arecibo + DRAO-ST image of a region of the Perseus-Pisces Supercluster. (Courtesy: Phil Kronberg) AUSAC Meeting · March 9 − 10, 2008

  2. AUSAC Meeting · March 9 − 10, 2008 The Rules of the Game • Pre-Nov 2006: -- 50% of R.A. telescope time for non ALFA- survey astronomy (~2400 hr per yr). -- Rx available: 327, 430 & 610 MHz; LBW, SBW, SBH, CB, CBH & XB. • Post-Nov 2006: -- 20% of R.A. telescope time for non ALFA- survey astronomy (~750 hr per yr). -- Rx available: 327 & 430 MHz; LBW, CB & XB; (plus SBW, SBH & CBH on “campaign” basis).

  3. AUSAC Meeting · March 9 − 10, 2008 PSR J1903+0327 – Confirming its High Mass J1903+0327 • Constraints on mass based on GBT and Ar timing. • “Classical” contribution to advance of periastron is not large. • J1903+0327 is more massive than any other NS with a precise mass determination. • The J1903+0327 mass excludes the “softest” EOSs. • Companion is likely to be a massive white dwarf or main sequence star. • PSR Period = 2.15 ms • Binary Period = 95 day • Orbital Eccentricity = 0.44 • PSR mass = 1.67±0.01Mo → implications for EOS of cold ultra-dense matter. (Courtesy: Paulo Freire)

  4. AUSAC Meeting · March 9 − 10, 2008 Red Dwarf “Pulsars” – TVLM 513 • Arecibo provides the wide bandwidth and high spectral resolution not available with the VLA → dynamic spectra of the pulses from TVLM 513. • Pulses resolved in both time and frequency → Brightness temperature > 1015 K for this electron cyclotron maser emission. • Radio emission occurs at electron cyclotron frequency → magnetic field strength of kiloGauss. • HSA (including Arecibo) used for VLBI follow-up observations.

  5. AUSAC Meeting · March 9 − 10, 2008 The Cosmic 3He Abundance (PI: Tom Bania) • 3He measurements can be used to test the theory of stellar nucleo-synthesis, put limits on models of Galactic chemical evolution and constrain Big-Bang nucleo-synthesis. • Mass loss from PNe should be substantially enriched in 3He, and its abundance is an important test of stellar evolution theory. • 3He+ has a hyperfine transition at 8665 MHz, which is detected in a composite Arecibo spectrum for NGC6210 and 6891. • Find Arecibo X-band baselines are much better than those at L-band.

  6. AUSAC Meeting · March 9 − 10, 2008 HI Forbidden-Velocity Wings • 2004-6: Arecibo (LBW and ALFA) + GBT observations of 22 FVWs. • 12-13 show shell-type structure; “missing” SNRs? • 9-10 show cloud-type structure; halo clouds or HVCs? 004-6: HVC LDS b=−0.5° (Courtesy: Ji-hyun Kang)

  7. AUSAC Meeting · March 9 − 10, 2008 High-Resn HI Image of Smith’s Cloud • GBT image has HPBW = 9‘ • Arecibo ALFA image has HPBW = 3.5‘ • Smith’s Cloud is an HVC plunging into the Galaxy and displaying signs of interaction • Arecibo images show evidence for hydrodynamic phenomena • Low-velocity gas (red) appears to wrap around the Cloud, interpreted as gas stripped from the Cloud and decellerated by Milky Way halo gas GBT (Courtesy: Jay Lockman) ALFA

  8. AUSAC Meeting · March 9 − 10, 2008 The Molecular Spectra of ULIRGs Zw 049.057 Arp 220 IC 860 CH2NH HCN v2=1, J=3 transition H2CO HCN (v2=1) CH triplet (λ9 cm) Excited OH (main line) Co-added H119α-H127α (λ9 cm) rms noise = 50 μJy/bm

  9. AUSAC Meeting · March 9 − 10, 2008 Zeeman Effect in ULIRG Megamasers (PI’s: Tim Robishaw & Carl Heiles) • Many OH megamasers in ULIRGs show Zeeman splitting of individual components yielding typical line-of-sight magnetic fields of 0.3-18 mGauss. • Following-up their initial detection of this phenomenon for ULIRGS, the P.I.’s are now making a Zeeman survey all suitable ULIRG OHMs in the Arecibo sky. • Linear polarization of the OHM in Arp 220 yields a Rotation Measure. • To resolve the Zeeman components spatially, VLBI has been made using the HSA (including Arecibo) allowing investigation of the origins of the magnetic fields.

  10. AUSAC Meeting · March 9 − 10, 2008 An H2O Megamaser at z = 2.64 (PI’s: Paola Castangia & Violetta Impellizzeri) • MG J0414+0534 is a gravitationally lensed QSO at z = 2.64. • H2O megamaser emission detected from it at Ef & VLA. Line is blueshifted relative to the QSO by 300 kms-1. • Being monitored at Ar for variability of line and continuum and to search for redshifted components. If such components are found indicates a “disk maser” rather than a “jet maser”. • After first 4 sessions, line profile appears very stable. No conclusive evidence yet for redshifted components.

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