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41.
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Jason Glenn Christopher K. Walker Erick T. Young 《International Journal of Infrared and Millimeter Waves》1997,18(2):285-300
We present the design of a broad band, 1.3 mm polarimeter for astronomical observations and the results of first light observations
at the Heinrich Hertz Telescope (HHT). The systematic polarization of the instrument plus telescope is 1.1%. The observed
linear polarization of DR 21,P=1.65%±0.14% andθ=16°±2°, is consistent with previous measurements. Our 0.9% upper limit on the linear polarization of Cepheus A is the first
1.3 mm measurement reported. With Cyclops it is possible to map the magnetic fields in several of the brightest molecular
cloud dust cores in the Milky Way. We comment on the expected performance of an achromatic Rexolite half-waveplate for λ=800μm to 1.3 mm. 相似文献
43.
The energy-momentum tensor in spontaneously broken non-Abelian gauge field theories is studied. The motivation is to show that recent results on the finiteness and gauge independence of S-matrix elements in gauge theories extends to observable amplitudes for transitions in a gravitational field. Path integral methods and dimensional regularization are used throughout. Green's functions Γμν(j)(q; p1,…,pj) involving the energy-momentum tensor and j particle fields are proved finite to all orders in perturbation theory to zero and first order in q, and finite to one loop order for general q. Amputated Green's functions of the energy momentum tensor are proved to be gauge independent on mass shell. 相似文献
44.
Cai T Ge Z Iezzi EB Glass TE Harich K Gibson HW Dorn HC 《Chemical communications (Cambridge, England)》2005,(28):3594-3596
New pyrrolidino derivatives of both diamagnetic and paramagnetic trimetallic nitride templated endohedral metallofullerenes were synthesized by the Prato reaction, isolated and characterized by means of MALDI-TOF MS, NMR and UV-vis spectroscopies. 相似文献
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Erick J. Weinberg 《Physics letters. [Part B]》1984,136(3):179-182
I give a general, gauge-invariant, definition of spherical symmetry in a gauge theory. I show that if the fields are required to be non-singular at the origin, such symmetry can occur only for certain values of the magnetic charge. One consequence is the existence of stable monopoles which are not spherically symmetric. 相似文献
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Computational Management Science - This paper proposes a multi-stage stochastic programming formulation based on affine decision rules for the reservoir management problem. Our approach seeks to... 相似文献
49.
Simon L. Rssler Benson J. Jelier Pascal F. Tripet Andrej Shemet Gunnar Jeschke Antonio Togni Erick M. Carreira 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(2):536-541
Electron‐transfer photocatalysis provides access to the elusive and unprecedented N‐pyridyl radical cation from selected N‐substituted pyridinium reagents. The resulting C(sp2)?H functionalization of (hetero)arenes furnishes versatile intermediates for the development of valuable aminated aryl scaffolds. Mechanistic studies that include the first spectroscopic evidence of a spin‐trapped N‐pyridyl radical adduct implicate SET‐triggered, pseudo‐mesolytic cleavage of the N?X pyridinium reagents mediated by visible light. 相似文献
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