3 research outputs found
Development of frequency domain multiplexing for the X-ray Integral Field Unit (X-IFU) on the Athena
We are developing the frequency domain multiplexing (FDM) read-out of
transition-edge sensor (TES) microcalorimeters for the X-ray Integral Field
Unit (X-IFU) instrument on board of the future European X-Ray observatory
Athena. The X-IFU instrument consists of an array of 3840 TESs with a
high quantum efficiency (90 \%) and spectral resolution =2.5 eV
7 keV (2800). FDM is currently the baseline readout system
for the X-IFU instrument. Using high quality factor LC filters and room
temperature electronics developed at SRON and low-noise two stage SQUID
amplifiers provided by VTT, we have recently demonstrated good performance with
the FDM readout of Mo/Au TES calorimeters with Au/Bi absorbers. An integrated
noise equivalent power resolution of about 2.0 eV at 1.7 MHz has been
demonstrated with a pixel from a new TES array from NASA/Goddard (GSFC-A2). We
have achieved X-ray energy resolutions 2.5 eV at AC bias frequency at 1.7
MHz in the single pixel read-out. We have also demonstrated for the first time
an X-ray energy resolution around 3.0 eV in a 6 pixel FDM read-out with TES
array (GSFC-A1). In this paper we report on the single pixel performance of
these microcalorimeters under MHz AC bias, and further results of the
performance of these pixels under FDM.Comment: 8 pages, 4 figures, Proceedings of the SPIE Astronomical
Instrumentation "Space Telescopes and Instrumentation 2014: Ultraviolet to
Gamma Ray
Single Pixel Performance of a 32 x 32 Ti/Au TES Array With Broadband X-Ray Spectra
We are developing a kilo-pixels Ti/Au TES array as a backup option for Athena X-IFU. Here we report on single-pixel performance of a 32 × 32 array operated in a Frequency Division Multiplexing (FDM) readout system, with bias frequencies in the range 1-5 MHz. We have tested the pixels response at several photon energies, by means of a 55Fe radioactive source (emitting Mn-Kα at 5.9 keV) and a Modulated X-ray Source (MXS, providing Cr-Kα at 5.4 keV and Cu-Kα at 8.0 keV). First, we report the procedure used to perform the detector energy scale calibration, usually achieving a calibration accuracy better than ∼0.5 eV in the 5.4-8.9 keV energy range. Then, we present the measured energy resolution at the different energies (best single pixel performance: ΔEFWHM = 2.40 ± 0.09 eV @ 5.4 keV; 2.53 ± 0.10 eV @ 5.9 keV; 2.78 ± 0.16 eV @ 8.0 keV), investigating also the performance dependency from the pixel bias frequency and the count rate. Thanks to long background measurements (∼1 d), we finally detected also the Al-Kα line at 1.5 keV, generated by fluorescence inside the experimental setup. We analyzed this line to obtain a first assessment of the single-pixel performance also at low energy (ΔEFWHM = 1.91 eV ± 0.21 eV @ 1.5 keV), and to evaluate the linearity of the detector response in a large energy band (1.5-8.9 keV). ImPhys/Optic
A test platform for the detection and readout chain for the Athena X-IFU
International audienceWe present a test platform for the Athena X-IFU detection chain, which will serve as the first demonstration of the representative end-to-end detection and readout chain for the X-IFU, using prototypes of the future flight electronics and currently available subsystems. This test bench, housed in a commercial two-stage ADR cryostat, includes a focal plane array placed at the 50 mK cold stage of the ADR with a kilopixel array of transition-edge sensor microcalorimeter spectrometers and associated cold readout electronics. Prototype room temperature electronics for the X-IFU provide the readout, and will evolve over time to become more representative of the X-IFU mission baseline. The test bench yields critical feedback on subsystem designs and interfaces, in particular the warm readout electronics, and will provide an in-house detection system for continued testing and development of the warm readout electronics and for the validation of X-ray calibration sources. In this paper, we describe the test bench subsystems and design, characterization of the cryostat, and current status of the project