FOCCoS for Subaru PFS

Antonio Cesar de Oliveira; Ligia Souza de Oliveira; Marcio Vital de Arruda; Jesulino Bispo dos Santos; Lucas Souza Marrara; Vanessa Bawden de Paula Macanhan; Joao Batista de Carvalho Oliveira; Rodrigo de Paiva Vilacca; Tania Pereira Dominici; Laerte Sodre Junior; Claudia Mendes de Oliveira; Hiroshi Karoji; Hajime Sugai; Atsushi Shimono; Naoyuki Tamura; Naruhisa Takato; Akitoshi Ueda

doi:10.1117/12.925745

arXiv · 1210.2751

FOCCoS for Subaru PFS

Antonio Cesar de Oliveira·Ligia Souza de Oliveira·Marcio Vital de Arruda·Jesulino Bispo dos Santos·Lucas Souza Marrara·Vanessa Bawden de Paula Macanhan·Joao Batista de Carvalho Oliveira·Rodrigo de Paiva Vilacca·Tania Pereira Dominici·Laerte Sodre Junior·Claudia Mendes de Oliveira·Hiroshi Karoji·Hajime Sugai·Atsushi Shimono·Naoyuki Tamura·Naruhisa Takato·Akitoshi Ueda

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Abstract

The Fiber Optical Cable and Connector System (FOCCoS), provides optical connection between 2400 positioners and a set of spectrographs by an optical fibers cable as part of Subaru PFS instrument. Each positioner retains one fiber entrance attached at a microlens, which is responsible for the F-ratio transformation into a larger one so that difficulties of spectrograph design are eased. The optical fibers cable will be segmented in 3 parts at long of the way, cable A, cable B and cable C, connected by a set of multi-fibers connectors. Cable B will be permanently attached at the Subaru telescope. The first set of multi-fibers connectors will connect the cable A to the cable C from the spectrograph system at the Nasmith platform. The cable A, is an extension of a pseudo-slit device obtained with the linear disposition of the extremities of the optical fibers and fixed by epoxy at a base of composite substrate. The second set of multi-fibers connectors will connect the other extremity of cable A to the cable B, which is part of the positioner's device structure. The optical fiber under study for this project is the Polymicro FBP120170190, which has shown very encouraging results. The kind of test involves FRD measurements caused by stress induced by rotation and twist of the fiber extremity, similar conditions to those produced by positioners of the PFS instrument. The multi-fibers connector under study is produced by USCONEC Company and may connect 32 optical fibers. The tests involve throughput of light and stability after many connections and disconnections. This paper will review the general design of the FOCCoS subsystem, methods used to fabricate the devices involved and the tests results necessary to evaluate the total efficiency of the set.

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Antonio Cesar de Oliveira, Ligia Souza de Oliveira, Marcio Vital de Arruda, Jesulino Bispo dos Santos, Lucas Souza Marrara, Vanessa Bawden de Paula Macanhan, Joao Batista de Carvalho Oliveira, Rodrigo de Paiva Vilacca, Tania Pereira Dominici, Laerte Sodre Junior, Claudia Mendes de Oliveira, Hiroshi Karoji, Hajime Sugai, Atsushi Shimono, Naoyuki Tamura, Naruhisa Takato, Akitoshi Ueda. 2012-10-09. FOCCoS for Subaru PFS. https://doi.org/10.1117/12.925745

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