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TianQin is a planned space-based gravitational wave (GW) observatory consisting of three earth orbiting satellites with an orbital radius of about $10^5~{\rm km}$. The satellites will form a equilateral triangle constellation the plane of which is nearly perpendicular to the ecliptic plane. TianQin aims to detect GWs between $10^{-4}~{\rm Hz}$ and $1~{\rm Hz}$ that can be generated by a wide variety of important astrophysical and cosmological sources, including the inspiral of Galactic ultra-compact binaries, the inspiral of stellar-mass black hole binaries, extreme mass ratio inspirals, the merger of massive black hole binaries, and possibly the energetic processes in the very early universe or exotic sources such as cosmic strings. In order to start science operations around 2035, a roadmap called the 0123 plan is being used to bring the key technologies of TianQin to maturity, supported by the construction of a series of research facilities on the ground. Two major projects of the 0123 plan are being carried out. In this process, the team has created a new generation $17~{\rm cm}$ single-body hollow corner-cube retro-reflector which has been launched with the QueQiao satellite on 21 May 2018; a new laser ranging station equipped with a $1.2~{\rm m}$ telescope has been constructed and the station has successfully ranged to all the five retro-reflectors on the Moon; and the TianQin-1 experimental satellite has been launched on 20 December 2019 and the first round result shows that the satellite has exceeded all of its mission requirements.

Relata-se no presente trabalho a avaliação genotípica de progênies e indivíduos de açaí no estado do Pará para os caracteres altura (ALT), diâmetro (DIAM), número de folhas vivas (NFV), altura do primeiro cacho (AC), número de perfilhos (NP), presença de cachos (PC), comprimento do internodio (CI) e sobrevivência (SOB). Apresenta-se também estimativas de parâmetros genéticos e ambientais que permitem inferir sobre o controle genético e nível de variabilidade genética presente no material avaliado, assumindo um sistema reprodutivo misto com a ocorrência ao acaso de 12,9% de autofecundação. Foi empregada a metodologia REML/BLUP. De um modo geral, com exceção dos caracteres diâmetro e sobrevivência, todas as demais apresentaram variabilidade genética expressiva, evidenciando o grande potencial para a seleção na própria população experimental. Considerando as duas taxas de autofecundação (0% e 12,9%), as diferenças nas estimativas dos ganhos foram desprezíveis. A seleção individual apresentou maior estimativa de ganho genético para o caráter número de perfilhos relativamente ao estimado para a seleção de progênies. Usando técnicas de análise multivariada foram obtidos seis grupos divergentes, os quais podem orientar cruzamentos visando a busca de descendentes heteróticos. Made available in DSpace on 2011-10-26T00:01:55Z (GMT). No. of bitstreams: 1 100220093347v13n4artigo05.pdf: 82616 bytes, checksum: 23073852e26346477d9aad4ee900063c (MD5) Previous issue date: 2008-05-20

Sub-nanometer distance stabilization and positioning of large optical structures is a key active control issue for future space telescopes needing picoradian precision. The paper presents solutions and results of a leading experiment, named COSI (Control Optics Structure Interaction), aimed at investigating Fabry-Pérot cavities as active optical links, capable of stiffening large and massive structures operating in vacuum. The optical length of each cavity is actuated by a PZT-driven mechanism and the cavity ensemble is controlled by a model-based Digital Control Unit. The first experiment stabilized the relative tip-tilt motion of two 6.9 kg annular plates, 0.5 m distant. A residual error, lower than 3t-½ pm (1s), t>0.1s, was achieved in presence of severe environment noise and artificial micrometer distance variations, thus fully demonstrating feasibility of COSI concept and technology.