Optimal Layout Design for Agricultural Facility Using Simulated Annealing

Rosana G. Moreira, Editor-in-Chief; Texas A&M UniversityThis is a Technical Paper from International Commission of Agricultural Engineering (CIGR, Commission Internationale du Genie Rural) E-Journal Volume 5 (2003): T. Satake, O. Sataka, Y. Ohta, and T. Furuya. Optimal Layout Design for Agricultural Facility Using Simulated Annealing. Vol. V. May 2003

183 GHz H2_2O maser emission around the low-mass protostar Serpens SMM1

We report the first interferomteric detection of 183 GHz water emission in the low-mass protostar Serpens SMM1 using the Submillimeter Array with a resolution of 3$"$ and rms of $\sim$7 Jy in a 3 km s$^{-1}$ bin. Due to the small size and high brightnessof more than 240 Jy/beam, it appears to be maser emission. In total three maser spots were detected out to $\sim$ 700 AU from the central protostar, lying along the red-shifted outflow axis, outside the circumstellar disk but within the envelope region as evidenced by the continuum measurements. Two of the maser spots appear to be blue-shifted by about 1 to 2 km s$^{-1}$. No extended or compact thermal emission from a passively heated protostellar envelope was detected with a limit of 7 Jy (16 K), in agreement with recent modelling efforts. We propose that the maser spots originate within the cavity walls due to the interaction of the outflow jet with the surrounding protostellar envelope. Hydrodynamical models predict that such regions can be dense and warm enough to invert the 183 GHz water transition.Comment: Accepted for ApJ letters, 2 figure

Microscopic and Macroscopic Signatures of Antiferromagnetic Domain Walls

Magnetotransport measurements on small single crystals of Cr, the elemental antiferromagnet, reveal the hysteretic thermodynamics of the domain structure. The temperature dependence of the transport coefficients is directly correlated with the real-space evolution of the domain configuration as recorded by x-ray microprobe imaging, revealing the effect of antiferromagnetic domain walls on electron transport. A single antiferromagnetic domain wall interface resistance is deduced to be of order $5\times10^{-5}\mathrm{\mu\Omega\cdot cm^{2}}$ at a temperature of 100 K.Comment: 3 color figure