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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).

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 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.

Four different thermal-vacuum tests were performed on AMICA Star Tracker (AST) in the period March-July 2006 in the space simulator of the SERMS laboratory in Terni-Italy. Each of these tests was designed to verify different AST camera design features. The Thermal Balance test was conceived to validate the thermo-elastic model of the instrument and the active and passive thermal control subsystems. The Thermal Vacuum Cycling test was conceived to validate the AST electronics operative and survival temperature limits under vacuum conditions. The worst hot and cold operative and survival limits of the lens and filters in the AST optical system were assessed by means of the “Sun in the lens” and Lens Cold tests.

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.

Being in charge of the thermal design and analysis for three external payloads that will fly on the ISS (EuTEF, EUROPA and LOBSTER) we highlight in this paper the commonality among them: they are attached to standard adapter plates and have standard resources in terms of power and mass allocation. These payloads, despite these commonalities have specific features due to the different scientific targets, are in different development phases and occupy various locations outside the International Space Station (ISS). Even if thermal requirements are not substantially different the different locations imply different environment and therefore different thermal control solution. Also analytical models of the ISS are different due to ISS development phase and details in proximity of payload location. The paper goes through common thermal design choices and specific solutions adapted to the specific needs of each of them.

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.

This paper describes the thermal modeling and analyses performed on the LISA Technology Package (LTP), with special attention to the frequency domain requirements on the sensitive instrumentation. The new approach is presented, and the modeling and analysis phases are described in detail. Results about LTP thermal stability in the frequency domain are shown, and obtained though two alternate approaches. The first one consists in the study of the transient response of the system to a periodic input with a frequency equal to the minimum frequency of interest, using the well known low-pass filtering properties of the thermal systems. The second is based on the generation of a time dependent input, starting from its Power Spectral Density definition: this input is used to run a transient thermal analysis and finally transform its results into the frequency domain. Thermal stability assessment studies have been performed also at spacecraft level and are well described in [ref. 3].