Status of resolve instrument onboard x-ray imaging and spectroscopy mission (XRISM)

.Resolve is a payload hosting an x-ray microcalorimeter detector operated at 50 mK in the x-ray imaging and spectroscopy mission. It is currently under development as part of an international collaboration and is planned to be launched in 2023. A primary technical concern is the microvibration interference in the sensitive microcalorimeter detector caused by the spacecraft bus components. We conducted a series of verification tests in 2021 to 2022 on the ground, the results of which are reported here. We defined the microvibration interface between the spacecraft and the Resolve instrument. In the instrument-level test, the flight-model hardware was tested against the interface level by injecting it with microvibrations and evaluating the instrument response using the 50 mK stage temperature stability, adiabatic demagnetization refrigerator magnet current consumption rate, and detector noise spectra. We found strong responses when injecting microvibration at ∼200, 380, and 610 Hz. In the former two cases, the beat between the injected frequency and cryocooler frequency harmonics were observed in the detector noise spectra. In the spacecraft-level test, the acceleration and instrument responses were measured with and without suspension of the entire spacecraft. The reaction wheels (RWs) and inertial reference units (IRUs), two major sources of microvibration among the bus components, were operated. In conclusion, the observed responses of Resolve are within the acceptable levels in the nominal operational range of the RWs and IRUs. There is no evidence that the resultant energy resolution degradation is beyond the current allocation of noise budget.

“…The interface levels and frequency ranges (Fig. 4) were given based on the SXS results for (1) and on a component-level test for (2). The stricter of the two was applied for (3).…”

Section: Interfacementioning

confidence: 99%

“…The X-Ray Imaging and Spectroscopy Mission (XRISM) is an x-ray observatory planned to be launched in 2023. 1 One of the scientific payloads is Resolve, 2 which hosts an x-ray microcalorimeter for high resolution spectroscopy. It was developed under the collaboration of JAXA, NASA, ESA, and universities and institutes under these agencies.…”

Section: Introductionmentioning

confidence: 99%

Ground test results of the microvibration interference for the x-ray microcalorimeter onboard x-ray imaging and spectroscopy mission

Hasebe

Tsujimoto

Awaki

et al. 2023

“…The x-ray integral field unit (X-IFU) microcalorimeter instrument, to be flown on ESA's flagship mission called Athena, has been in development for more than 7 years. 22 This development has added a lot of maturity to the design of the LMS detection chain architecture with many members of the LMS team participating in this mission. Although optimized for very different x-ray astrophysics observations and thus for a very different x-ray energy range with different performance characteristics, the basic TESs being used in the microcalorimeter array, the TDM multiplexing, and the room temperature electronics are very similar.…”

Section: Introductionmentioning

confidence: 99%

Line emission mapper microcalorimeter spectrometer

Bandler,

Adams,

Amatucci

et al. 2023

Self Cite

.The line emission mapper (LEM) is a probe-class mission concept that is designed to detect x-ray emission lines from hot ionized gas (T > 106 K) that will enable us to test galaxy evolution theories. It will permit us to study the effects of stellar and black-hole feedback and flows of baryonic matter into and out of galaxies. The key to being able to study the hot gases that are otherwise invisible to current imaging x-ray spectrometers is that the energy resolution is sufficient to use cosmological redshift to separate extragalactic source lines from foreground Milky Way emission. LEM incorporates a large-format microcalorimeter array instrument called the LEM microcalorimeter spectrometer (LMS) with a light-weight x-ray optic with 10” half power diameter angular resolution. The LMS microcalorimeter array has pixels with 15″ pixel pitch over a 33′ field of view (FOV) optimized for the 0.3 to 2 keV energy band. The central 7′ region of the array has an energy resolution of 1.3 eV at 1 keV and the rest of the FOV has 2.5 eV energy resolution at 1 keV. The array will be read out with state-of-the-art time-division multiplexing. We present an overview of the LMS instrument, including details of the entire detection chain, the focal plane assembly, as well as the cooling system and overall mechanical and thermal design. For each of the key technologies, we discuss the current technology readiness level and the plan to advance them to be ready for flight. We also describe the current system design and our estimate for the mass, power, and data rate of the instrument. The design details presented concentrate primarily on the unique aspects of the LMS design compared with prior missions and confirm that the type of microcalorimeter instrument needed for LEM is not only feasible but also technically mature.

“…Resolve 7 x-ray microcalorimeter for the x-ray imaging and spectroscopy mission (XRISM) 8 was designed to be almost the same as the SXS 5,6 for ASTRO-H 4 to recover its excellent science programs yet to be achieved due to the unexpected early loss of the mission by the malfunction of the spacecraft attitude control in March 2016. The SXS suffered from the EMI from the bus system that degraded the detector performance, 9 which was only recognized after the integration of the instrument into the spacecraft.…”

Section: Introductionmentioning

confidence: 99%

“…The conductive EMI was also tested, which is described in a separate article. 7 The article is structured as follows. In Sec.…”

Section: Introductionmentioning

confidence: 99%

Ground test results of the electromagnetic interference for the x-ray microcalorimeter onboard XRISM

Kurihara

Tsujimoto

Eckart

et al. 2023

Self Cite

.Electromagnetic interference (EMI) for low-temperature detectors is a serious concern in many missions. We investigate the EMI caused by the spacecraft components to the x-ray microcalorimeter of the Resolve instrument onboard the x-ray imaging and spectroscopy mission, which is currently under development by an international collaboration and is planned to be launched in 2023. We focus on the EMI from (a) the low-frequency magnetic field generated by the magnetic torquers (MTQ) used for the spacecraft attitude control and (b) the radio-frequency (RF) electromagnetic field generated by the S and X band antennas used for communication between the spacecraft and the ground stations. We executed a series of ground tests both at the instrument and spacecraft levels using the flight-model hardware in 2021–2022 in a JAXA facility in Tsukuba. We also conducted electromagnetic simulations partially using the Fugaku high-performance computing facility. The MTQs were found to couple with the microcalorimeter, which we speculate through pick-ups of low-frequency magnetic field and further capacitive coupling. There is no evidence that the resultant energy resolution degradation is beyond the current allocation of noise budget. The RF communication system was found to leave no significant effect. We present the result of the tests and simulation in this article.