EURECA: European-Japanese microcalorimeter array

The EURECA project aims to demonstrate technological readiness of a micro-calorimeter array for application in future X-ray astronomy missions, like Constellation-X, EDGE, and XEUS. The prototype instrument consists of a 5 × 5 pixel array of TES-based micro-calorimeters read out by two SQUID-amplifier channels using frequency-domain-multiplexing (FDM) with digital base-band feedback. The detector array is cooled by a cryogen-free cryostat consisting of a pulse tube cooler and a two stage ADR. Initial tests of the system at the PTB beam line of the BESSY synchrotron showed stable performance and an X-ray energy resolution of 1.5 eV at 250 eV for read-out of one TES-pixel only. Next step is deployment of FDM to read-out the full array. Full performance demonstration is expected end 2008.This work was financially supported by the Dutch Organization for Scientific Research (NWO).Peer Reviewe

[email protected]; phone +31 30 2535710; fax +31 30 2540860, www.sron.nl Space Telescopes and Instrumentation

ABSTRACT The EURECA (EURopean-JapanEse Calorimeter Array) project aims to demonstrate the science performance and technological readiness of an imaging X-ray spectrometer based on a micro-calorimeter array for application in future X-ray astronomy missions, like Constellation-X and XEUS. The prototype instrument consists of a 5 x 5 pixel array of TES-based micro-calorimeters read out by by two SQUID-amplifier channels using frequency-domain-multiplexing (FDM). The SQUID-amplifiers are linearized by digital base-band feedback. The detector array is cooled in a cryogenfree cryostat consisting of a pulse tube cooler and a two stage ADR. A European-Japanese consortium designs, fabricates, and tests this prototype instrument. This paper describes the instrument concept, and shows the design and status of the various sub-units, like the TES detector array, LC-filters, SQUID-amplifiers, AC-bias sources, digital electronics, etc. Initial tests of the system at the PTB beam line of the BESSY synchrotron showed stable performance and an X-ray energy resolution of 1.58 eV at 250 eV and 2.5 eV @ 5.9 keV for the read-out of one TES-pixel only. Next step is deployment of FDM to read-out the full array. Full performance demonstration is expected mid 2009

A waveguide-coupled millimetre-wave TES bolometer suitable for 2-D arrays

We are developing a single-pixel antenna-coupled bolometric detector for use in low-background millimetre-wave astronomy. The device consists of a radial probe in a rectangular waveguide coupled to a Ti/Au transition edge sensor (TES). The signal propagates from the antenna along a superconducting microstrip line into a metal resistor on a thermally isolated Si3N4 island, where the TES is also located. We have designed and built prototype pixels optimised for 150 GHz band measurements. We discuss our progress in the development as well as the first results from dark measurements. PAC

EURECA Software

Trabajo presentado a la 18th annual Astronomical Data Analysis Software and Systems (ADASS XVIII) Conference celebrada en Québec (Canada) del 2 al 5 de Noviembre de 2008.EURECA (EURopEan Calorimeter Array) is a project to develop a fully functional instrument based on transition edge sensors (TES). It shall demonstrate technical readiness for a detector which can be used in the X-ray missions of the next years, like XEUS and EDGE. The produced amount of data can be up to 10 MByte per second, depending on the mode of the instrument. To process and to analyze the data of this EURECA instrument, specific software has to be developed in order to reach the goal of the project: an energy resolution of 1 eV at 1 KeV. On the one hand the software has to be flexible and modular to test several algorithms, on the other hand it should be a straightforward pipeline system to analyze the same data set with different parameters and compare the results. Furthermore display tools to display scientific raw data, housekeeping data and the results of the analysis are required. These display tools will be used for quick look analysis as well as during off-line analysis.Peer Reviewe

Development of an array of transition edge sensors for application in X-ray astronomy

We report on the development activities towards a cryogenic array of micro-calorimeters, based on voltage-biased Ti/Au transition edge thermometers. Fabrication issues are discussed along the lines of two fabrication routes. One route utilizes bulk micromachining in [1 1 0] Si wafers, the other route surface micromachining with a sacrificial layer. Prototype 5×5 arrays have been fabricated and we present the first performance data: Two arrays were irradiated with 5.9 keV X-ray irradiation and an energy resolution of 6–7 eV FWHM was obtained. The arrays have been designed and their performance is analyzed with the aid of finite element simulation of the electrothermal behavior of a single pixel and thermal conductivity in the supporting structure

EURECA - A European-Japanese micro-calorimeter array

Trabajo presentado como comunicación a la Conferencia "Space Telescopes and Instrumentation 2008: Ultraviolet to Gamma Ray" celebrada en Francia el 23 de Junio del 2008.The EURECA (EURopean-JapanEse Calorimeter Array) project aims to demonstrate the science performance and technological readiness of an imaging X-ray spectrometer based on a micro-calorimeter array for application in future X-ray astronomy missions, like Constellation-X and XEUS. The prototype instrument consists of a 5 x 5 pixel array of TES-based micro-calorimeters read out by by two SQUID-amplifier channels using frequency-domain-multiplexing (FDM). The SQUID-amplifiers are linearized by digital base-band feedback. The detector array is cooled in a cryogenfree cryostat consisting of a pulse tube cooler and a two stage ADR. A European-Japanese consortium designs, fabricates, and tests this prototype instrument. This paper describes the instrument concept, and shows the design and status of the various sub-units, like the TES detector array, LC-filters, SQUID-amplifiers, AC-bias sources, digital electronics, etc. Initial tests of the system at the PTB beam line of the BESSY synchrotron showed stable performance and an X-ray energy resolution of 1.58 eV at 250 eV and 2.5 eV @ 5.9 keV for the read-out of one TES-pixel only. Next step is deployment of FDM to read-out the full array. Full performance demonstration is expected mid 2009.The authors acknowledge an ESA Technological Research Program contract for the development of TES-arrays and SQUIDs, being a significant support to the EURECA program. Also the recent ESA TRP contract for the development of SQUID-based electronics is of crucial importance for this work.Peer Reviewe

A cryogenic imaging x-ray spectrometer for XEUS readout by frequency-division SQUID multiplexers

A micro-calorimeter array with superconducting transition-edge sensors read out by a SQUID-based frequency-domain multiplexer is under development for the X-ray imaging spectrometer on board ESA's X-ray Evolving Universe Spectroscopy (XEUS) mission. The XEUS requirements are 2 and 5 eV FWHM energy resolution for 2 and 7 keV X-rays, respectively. An array of 32 × 32 pixels with 250 micron square pixels is envisaged. SRON and MESA+ have developed 5 × 5 imaging micro-calorimeter prototype arrays along a bulk micromachining and a surface micromachining route. The present state of array design and development with emphasis on pixel-to-pixel performance measurements of thermal and I-V characteristics, sensor noise and energy resolution are presented. SRON and VTT are developing frequency-domain multiplexing with SQUID current amplifiers to read out the 32 × 32 array. The concept for the frequency division multiplexing read-out will be presented and its performance characteristics discussed. Recent results of sensor operation under AC-bias (500 kHz) are presented

XEUS: The physics of the hot evolving universe

This paper describes the next generation X-ray observatory XEUS which has been submitted to the European Space Agency in the framework of the Cosmic Vision 2015-2025 competition and has been selected for an assessment study. The paper summarizes the scientific goals and instrumental concepts of the proposed X-ray telescope with 5 m2 effective area and angular resolution better than 5 arc sec.Peer Reviewe