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The Alpha Magnetic Spectrometer (AMS) is a particle physics detector designed to measure charged cosmic rays spectra and high energy photons on board of the International Space Station (ISS). The large acceptance (0.5 m2sr), the long mission duration (3 years) and the state of the art particle identification techniques will allow AMS to provide the most sensitive search up to date for the existence of anti matter nuclei and for the origin of dark matter. AMS02 now is in its final integration phase at CERN. To verify the functional performance of the detectors and of the key subsystems of the Thermal Control System under vacuum condition and to validate the thermal mathematical model of AMS02 a system level thermo-vacuum test will be performed in the Large Space Simulator (LSS) of ESA at ESTEC (the Netherlands).

A Heat Switch has been developed, namely a device able to autonomously regulate its own thermal conductance in function of the equipment dissipation and environmental heat sink conditions. It is based on a Loop Heat Pipe (LHP) technology, with a passive bypass valve which diverts the flow to the Compensation Chamber when needed for regulation purposes. The target application is the potential use on a Mars Rover thermal control system. The paper recalls the Heat Switch design, and reports the results of an extensive test campaign on the ground demonstrator. The performance of the device was found extremely satisfying, and often exceeded the system requirements.

The future Mars rover thermal design presents a unique challenge to the thermal engineers: the need arises for a thermal control system able to keep rover elements within their operational and non-operational temperature ranges in the face of extreme environmental conditions, characterized by broad day/night temperature excursions, cold biased conditions and long periods in standby modes induced by dust storms. A thermal device is needed, which allows the removal of excess heat from dissipating units during the Martian day and to keep them above their minimum operational/survival temperature during night. Moreover the scientific goals introduce strict requirements in terms of allowable internal components temperature ranges and thermal stability, which the candidate device has to fulfill against wide-ranging power dissipation modes. Such a device has been called Variable Thermal Conductance Device, or ‘Heat Switch’.

The AMS-02 experiment is a space-born instrument designed to perform high precision measurements of cosmic rays and γ-ray fluxes on board of the International Space Station (ISS). All the components of the AMS experiment are designed to withstand the mechanical stresses in the launch phase and to operate in vacuum in a wide range of temperatures. In order to verify the performance of the hardware in harsh conditions like the flight ones, all the components of the AMS instruments undergo a severe qualification procedure before the integration into the detector. In this paper, we will report on the thermo-vacuum tests on the L-TOF (Lower Time of Flight) and ECAL (Electromagnetic CALorimeter) detectors, successfully performed in the SERMS laboratory in June and September 2006, respectively.

This paper describes the Thermal Balance test that has been performed on EuTEF (European Technology Exposure Facility) platform, to be flown in October 2007 as an attached payload of Columbus module to the ISS. The thermal control system of EuTEF is based on a passive concept, with several different payloads being each one a self-standing technological experiment, with a centralized power supply and data handling. Each instrument has its own TCS, independent one another: they are individually insulated by MLI. The test has been performed with EuTEF Flight Model (FM) on the Passive Attach System to have representative thermal flight-like interfaces. Simulation of close-to-real flight environmental heat loads have been accomplished in a vacuum chamber (at INTESPACE, Toulouse-F) by means of a solar beam and a spin table suitably oriented to simulate a critical identified orbit, among all the possible on the ISS.

This paper reports on the approach followed for the TCS verification of the payload AMS-02 (Alpha Magnetic Spectrometer), aiming at the qualification of the entire system, in steps, for the space environment. AMS-02 is a state-of-the-art experiment composed by a stack of seven different particle detectors, each of them having its own electronics and control equipments. It will be installed on the International Space Station Starboard segment S3 of the main Truss, and will be a 6500 kg payload, with a power consumption of 2000 W. The verification philosophy is driven by the need to qualify the flight hardware and by the necessary confirmation and correlation of the thermal mathematical models, based on experimental data. The hardware used on AMS-02 is derived from the state-of-the-art ground based detectors for high energy physics, hence not yet proven for operations in vacuum and in extreme thermal environment.

The satellite AGILE (Astro-rivelatore Gamma a Immagini LEggero, “Light Gamma Ray Imaging Detector”) is a promising instrument for near-earth space research of the Italian Space(ASI) during the years 2007-2009: its scientific instrumentation has optimal imaging capabilities in both the gamma-ray energy range (30 MeV - 30 GeV) and hard X-ray range (15 - 45 keV). It will study the phenomena occurring in the high energy spectrum, such as: Active Galactic Nuclei, Gamma Ray Bursts, Gamma-ray Galactic Diffuse Emission, and more. The satellite was designed and built in years 2004-2006; this paper describes the design of the thermal control system of the satellite, with a survey of the flight prediction. As an example of uncertainty reduction, MLI performance characterization by test was done in an early phase of the AIV phase (i.e. well before the system level test), to meet stringent payload requirements in terms of temperature gradients and temperature stability.

Improvements on the thermal analysis for system perturbed by micro-thermal fluctuations are presented: the method applies to any kind of (small) perturbation, in particular to the random ones. Opposite to time domain conventional transient analysis, this method answers the need for frequency domain thermal analysis dictated by the newest scientific missions, with tight temperature stability requirements (expressed in the frequency domain). The small temperature fluctuations allow for assuming any thermal systems a linear one; hence linear system theory holds, and powerful tools to calculate key parameters like frequency response can be successfully employed. MIMO (Multi-Input-Multi-Output) systems theory is applied, the inputs being perturbations to the thermal system (boundary temperatures oscillations and power sources ripple of any shape: pulse, step, periodic, random, …), while the outputs are the temperatures of the sensible parts.

This paper updates on the Thermal Control System (TCS) of AMS (Alpha Magnetic Spectrometer). The Shuttle fleet grounding, after Columbia accident February 2003, has caused a delay in the AMS-02 project schedule, allowing to put additional effort on the TCS design optimization. This paper accounts for two-years extended numerical simulations, leading to a stable TCS baseline design. AMS (shown in Figure 1) is to be installed on the International Space Station (ISS) Starboard segment of the Truss, where it shall acquire data for three years with the Superfluid Helium magnet powered ON. After Superfluid Helium tank is depleted, operations continue taking data with instruments not requiring the magnetic field of the super-conducting magnet; this allows a fine characterization of the spectrum of atoms nuclei, for Solar System human exploration purposes. AMS payload has a mass of about 6500 kg, and a power budget of about 2kW.

This paper describes the Thermal Balance test that has been performed on the PAMELA telescope Pressurized Container (PC) to verify the performance of the PC Thermal Control System (TCS). The PC will be attached outside the Russian satellite RESOURS DK to be flown in2004 The thermal control system of the PAMELA PC is based on a mechanical pumped loop fed with Isooctane as working fluid. The test has been performed with PAMELA Structural Thermal Model (STM) inside the PC to have representative interfaces for the thermal control system. Simulation of close-to-real flight environmental heat loads have been accomplished in a vacuum chamber by means of a complex system of IR lamps suitably oriented toward the PC and mechanically mounted on a tubular structure outside the PC. Overall test results have been excellent; PAMELA thermal control system thermal/fluidic requested performance have been verified. PAMELA telescope thermal interfaces have been confirmed as well.

This paper reports on the Thermal Control System (TCS) of the AMS-02 (Alpha Magnetic Spectrometer). AMS-02 will be installed on the International Space Station (ISS) Starboard segment of the Truss in 2005, where it will acquire data for at least three years. The AMS-02 payload has a mass of about 6700 kg, a power budget of 2kW and consists of 5 different instruments, with their associated electronic equipment. Analytical integration of the AMS-02 thermal mathematical model is described in the paper, together with the main thermal design features. Stringent temperature stability requirements have been satisfied, providing a stable thermal environment that allows for easier calibration of the detectors. The overall thermal design uses a combination of standard and innovative concepts to fit specific instruments needs.