First Images of R Aquarii and its Asymmetric H$_{2}$O Shell

S. Ragland; H. Le Coroller; E. Pluzhnik; W. D. Cotton; W. C. Danchi; J. D. Monnier; W. A. Traub; L. A. Willson; J. -P. Berger; M. G. Lacasse

doi:10.1086/529573

arXiv · 0801.3488

First Images of R Aquarii and its Asymmetric H$_{2}$O Shell

S. Ragland·H. Le Coroller·E. Pluzhnik·W. D. Cotton·W. C. Danchi·J. D. Monnier·W. A. Traub·L. A. Willson·J. -P. Berger·M. G. Lacasse

View original source ↗Read source document ↗Export metadata ↓

Abstract

We report imaging observations of the symbotic long-period Mira variable R Aquarii (R Aqr) at near-infrared and radio wavelengths. The near-infrared observations were made with the IOTA imaging interferometer in three narrow-band filters centered at 1.51, 1.64, and 1.78 $μ$m, which sample mainly water, continuum, and water features, respectively. Our near-infrared fringe visibility and closure phase data are analyzed using three models. (a) A uniform disk model with wavelength-dependent sizes fails to fit the visibility data, and is inconsistent with the closure phase data. (b) A three- component model, comprising a Mira star, water shell, and an off-axis point source, provide a good fit to all data. (c) A model generated by a constrained image reconstruction analysis provides more insight, suggesting that the water shell is highly non-uniform, i.e., clumpy. The VLBA observations of SiO masers in the outer molecular envelope show evidence of turbulence, with jet-like features containing velocity gradients.

Explore related subjects

astro-ph

Keep this discovery

BibTeX RIS

S. Ragland, H. Le Coroller, E. Pluzhnik, W. D. Cotton, W. C. Danchi, J. D. Monnier, W. A. Traub, L. A. Willson, J. -P. Berger, M. G. Lacasse. 2008-01-23. First Images of R Aquarii and its Asymmetric H$_{2}$O Shell. https://doi.org/10.1086/529573

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2018

Putting The Together A Cyclical Baryonic Universe

There are multiple examples of gravitational losses in neutron stars and black holes. Protons and neutrons have been found to have enormous repulsive pressures that highly squeezed collapsing matter cannot overcome. The case against singularities follows. Galactic black hole gravitational losses can supply the missing dark energy. With highly squeezed nucleons, the big bang could begin as a hot core and a cold dark matter shell. The 21 cm. radiation data has identified baryon sized particles as cold dark matter. Highly squeezed nucleons will not decompose to produce antimatter. The flatness of the Universe is due to a baryonic bounce. The highly correlated galaxies originated from primordial black holes capturing hot core gasses.There is evidence that galaxies have not grown nor merged significantly since formation.

astro-ph↗

arXiv2018

Direct observation of high-speed plasma outflows produced by magnetic reconnection in solar impulsive events

Spectroscopic observations of a solar limb flare recorded by SUMER on SOHO reveal, for the first time, hot fast magnetic reconnection outflows in the corona. As the reconnection site rises across the SUMER spectrometer slit, significant blue- and red-shift signatures are observed in sequence in the Fe XIX line, reflecting upflows and downflows of hot plasma jets, respectively. With the projection effect corrected, the measured outflow speed is between 900-3500 km/s, consistent with theoretical predictions of the Alfvenic outflows in magnetic reconnection region in solar impulsive events. Based on theoretic models, the magnetic field strength near the reconnection region is estimated to be 19-37 Gauss.

astro-ph↗

arXiv2018

Multiwavelength evidence of the physical processes in radio jets

Over the last few years, high-quality X-ray imaging and spectroscopic data from Chandra and XMM-Newton have added greatly to the understanding of the physics of radio jets. Here we describe the current state of knowledge with an emphasis on the underlying physics used to interpret multiwavelength data in terms of physical parameters.

astro-ph↗