Multimode optomechanical systems are an emerging platform for studying fundamental aspects of matter near the quantum ground state and are useful in sensitive sensing and measurement applications. We study optomechanical cooling in a system where two nearly degenerate mechanical oscillators are coupled to a single microwave cavity. Due to an optically mediated coupling the two oscillators hybridize into a bright mode with a strong optomechanical cooling rate and a dark mode nearly decoupled from the system. We find that at high coupling, sideband cooling of the dark mode is strongly suppressed. Our results are relevant to novel optomechanical systems where multiple closely spaced modes are intrinsically present.

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In 2007, the Government of Costa Rica announced to the world its ambitious goal of turning into the first carbon neutral country by 2021. Following the announcement, governmental institutions, universities, NGOs and private companies have worked arduously on the creation of different initiatives to reach that goal. One innovative project is Irazú, consisting of the design, construction, launch, and operation of the first Central American satellite. The project is not just intended to enable a baseline for training scientists, engineers, and managers in the necessary skills to execute an end-to-end space project. It also aims to demonstrate a CubeSat Store & Forward (CS&F) System that enables transmission of biomass and carbon dioxide fixation data from a remote fast growth tree plantation in the lowlands of Costa Rica to a research facility for its post-processing and analysis. The Irazú project is led jointly by the Central American Association for Aeronautics and Space (ACAE) and the Costa Rica Institute of Technology (TEC). It also involves a variety of national and international stakeholders from government, academia, and industry. This paper is a continuation of previous reports on Irazú that were presented at the Workshop on Small Satellite Programs at the Service of Developing Countries over the last five International Astronautical Congresses. The project has already reached major milestones, such as the approval of the final design presented in the Critical Design Review (CDR), successful assembly of the manufactured structure and the components received from different CubeSat component providers, and successful performance during various environmental tests. The mission and satellite system architecture for a CS&F system were defined, which included the three primary components: the remote station, the spacecraft, and the ground segment. Experts from the National Aeronautics and Space Administration (NASA), Kyushu Institute of Technology (Kyutech) and Delft University of Technology (TU Delft) revised the design of Irazú. Advances in the Assembly, Integration & Testing (AI&T) phase are presented and discussed, which include the development of spacecraft components, testing of the communication link, assembly of the satellite and initial results of environmental testing. International cooperation is emphasized in this phase, because Costa Rican engineers carry out testing at the laboratories of the Kyushu Institute of Technology. Furthermore, advances in the satellite frequency coordination process and spacecraft registration for an emerging space nation are presented, as well as the lessons learned from the AI&T phase.@en

The Central American region has embarked on different endeavors related to space engineering in recent years. CubeSat missions are currently being independently developed in Costa Rica and Guatemala, with the main purpose of training the human resources, creating the know-how, and infrastructure necessary to execute end-to-end space missions. On the longer term, both groups seek to develop further small satellite missions that will allow scientists and engineers to address the needs of the region, which include remote sensing, communications, monitoring of drug trafficking, illegal fishing, assessing the impact of and preparing for climate change, among others. Both teams understand that to potentiate their capacities beyond the realm of these initial projects, cooperation among peer teams is mandatory. Due to the similar socio-economic situation of both countries and their similar level of development and geographical closeness, there exists a great potential for collaboration. In this scenario, it has been concluded that the best way to develop this collaboration is through the development of a joint space engineering project. This paper proposes a CubeSat mission that will initiate cooperation between research institutions in Central America, led by Universidad del Valle de Guatemala (UVG) and Costa Rica Institute of Technology (TEC). Previous examples of collaboration between countries of different regions in space-related projects are analyzed and discussed. A methodology developed by researchers at UVG is used to selecting the mission that would benefit the Central American region the most while considering programmatic risk and technical feasibility. This work serves as the basis for determining aspects such as spacecraft capabilities, specifications, and resources needed. Additionally, it helps define the different spacecraft subsystems and other mission features including project management, funding acquisition, testing, launch, and operations. The design philosophy is presented as well, which consists of incremental innovation, starting with the use of high Technology Readiness Level (TRL) spacecraft components from established suppliers, leading to subsystem development by universities and industry in the region. Furthermore, the distribution of responsibilities between participating organizations is defined based on the capabilities of the stakeholders.@en