Do coupled nested pendula have the same eigenfrequencies as pendula in cascade?

Autor(es)

Constancio, Jr., M. ^[1] ; Aguiar, O. D. ^[1] ; Keiser, G. McCurrach ^{[2, 3]} ; Malheiro, M. ^[2] ; Lemos, L. J. Rangel ^{[2, 4]}

Afiliação do(s) autor(es)

^[1] INPE, MCTI, BR-12227010 Sao Jose Dos Campos, SP - Brazil

^[2] Inst Tecnol Aeronaut, BR-12228900 Sao Jose Dos Campos, SP - Brazil

^[3] Stanford Univ, Stanford, CA 94305 - USA

^[4] Univ Fed Tocantins, BR-77824838 Araguaina, TO - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Instrumentation; v. 9, AUG 2014.
• Citações Web of Science: 0

Resumo

Over the last few years, several vibration isolation projects for gravitational wave detectors have been proposed. Some of them are related to N-stages cascaded systems which can achieve great factors of attenuation. However, these systems are usually very tall, which makes it difficult to build an efficient vaccum chamber for them. For this reason, this paper makes a comparison between a theoretical N-stage cascaded pendula with an experimental N-stage nested one. Preliminary results show that their resonant modes are very similar. The ratio between the results of experiment and theory is between 0.94 and 1.01 for the pendular modes and systematically close to 1.05 for the rotational modes. This result implies that an N-stage nested pendula set of about 1.4m height can have resonant modes similar to a cascaded pendula set of about 6.6m, which may suggests that a nested system can be theoretically treated as a cascaded one. So, the development of nested pendula can be an effective alternative of vibration isolation systems for future generations of gravitational wave detectors. (AU)

• Processo FAPESP: 12/22752-1 - Multi-nested pendula: um novo sistema de isolamento vibracional criogênico para o detector de ondas gravitacionais Advanced LIGO
• Beneficiário: Marcio Constâncio Junior
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 06/56041-3 - Nova física no espaço: ondas gravitacionais
• Beneficiário: Odylio Denys de Aguiar
• Modalidade de apoio: Auxílio à Pesquisa - Temático