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We present the first linear-polarization mosaicked observations performed by the Atacama Large Millimeter/submillimeter Array (ALMA). We mapped the Orion-KLeinmann-Low (Orion-KL) nebula using super-sampled mosaics at 3.1 and 1.3 mm as part of the ALMA Extension and Optimization of Capabilities program. We derive the magnetic field morphology in the plane of the sky by assuming that dust grains are aligned with respect to the ambient magnetic field. At the center of the nebula, we find a quasi-radial magnetic field pattern that is aligned with the explosive CO outflow up to a radius of approximately 12″ (∼5000 au), beyond which the pattern smoothly transitions into a quasi-hourglass shape resembling the morphology seen in larger-scale observations by the James-Clerk-Maxwell Telescope (JCMT). We estimate an average magnetic field strength mG and a total magnetic energy of 2 × 1045 erg, which is three orders of magnitude less than the energy in the explosive CO outflow. We conclude that the field has been overwhelmed by the outflow and that a shock is propagating from the center of the nebula, where the shock front is seen in the magnetic field lines at a distance of ∼5000 au from the explosion center. [ABSTRACT FROM AUTHOR]

Abstract: Recent papers by Samuel [S. Samuel, Phys. Rev. Lett. 90 (2003) 231101; S. Samuel, Int. J. Mod. Phys. D 13 (2004) 1753] declared that the linearized post-Newtonian effects are too small to have been measured in the recent experiment involving Jupiter and quasar [S.M. Kopeikin, Astrophys. J. Lett. 556 (2001) L1; E.B. Fomalont, S.M. Kopeikin, in: E. Ros, R.W. Porcas, A.P. Lobanov, J.A. Zensus (Eds.), Proc. 6th European VLBI Network Symp., MPIfR, Bonn, 2002 pp. 49–52, gr-qc/0206022; E.B. Fomalont, S.M. Kopeikin, Astrophys. J. 598 (2003) 704] that was used to measure the ultimate speed of gravity defined as a fundamental constant entering in front of each time derivative of the metric tensor in the Einstein gravity field equations. We describe our Lorentz-invariant formulation of the Jovian deflection experiment and confirm that effects are do observed, as contrasted to the erroneous claim by Samuel, and that they vanish if and only if the speed of gravity is infinite. [Copyright &y& Elsevier]

We report ALMA Band 7 (350 GHz) imaging at 0".4-0".6 resolution and Band 9 (696 GHz) at similar to 0".25 resolution of the luminous IR galaxies Arp 220 and NGC 6240. The long wavelength dust continuum is used to estimate interstellar medium masses for Arp 220 east and west and NGC 6240 of 1.9, 4.2, and 1.6 x 10(9) M-circle dot within radii of 69, 65, and 190 pc. The HCN emission was modeled to derive the emissivity distribution as a function of radius and the kinematics of each nuclear disk, yielding dynamical masses consistent with the masses and sizes derived from the dust emission. In Arp 220, the major dust and gas concentrations are at radii less than 50 pc in both counter-rotating nuclear disks. The thickness of the disks in Arp 220 estimated from the velocity dispersion and rotation velocities are 10-20 pc and the mean gas densities are n(H2) similar to 10(5) cm(-3) at R < 50 pc. We develop an analytic treatment for the molecular excitation (including photon trapping), yielding volume densities for both the HCN and CS emission with n(H2) similar to 2 x 10(5) cm(-3). The agreement of the mean density from the total mass and size with that required for excitation suggests that the volume is essentially filled with dense gas, i.e., it is not cloudy or like swiss cheese., Version of Record

We report on some preliminary results on the evolution and luminosity functions of submillijansky (sub-mJy) radio sources, based on the VLA Chandra Deep Field South (CDFS) sample. [ABSTRACT FROM PUBLISHER]