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Radio Astronomy -- Other Than ALFA Surveys

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

2 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). AUSAC Meeting · March 9 − 10, 2008

3 PSR J1903+0327 – Confirming its High Mass
Constraints on mass based on GBT and Ar timing. “Classical” contribution to advance of periastron is not large. J is more massive than any other NS with a precise mass determination. The J 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) AUSAC Meeting · March 9 − 10, 2008

4 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. AUSAC Meeting · March 9 − 10, 2008

5 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. AUSAC Meeting · March 9 − 10, 2008

6 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? HVC 004-6: LDS b=−0.5° (Courtesy: Ji-hyun Kang) AUSAC Meeting · March 9 − 10, 2008

7 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 AUSAC Meeting · March 9 − 10, 2008

8 The Molecular Spectra of ULIRGs
Arp 220 IC 860 Zw 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 AUSAC Meeting · March 9 − 10, 2008

9 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 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. AUSAC Meeting · March 9 − 10, 2008

10 An H2O Megamaser at z = 2.64 (PI’s: Paola Castangia & Violetta Impellizzeri) MG J 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. AUSAC Meeting · March 9 − 10, 2008


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