Vibration isolation system for cryocoolers of soft x-ray spectrometer on-board ASTRO-H (Hitomi)

Takei, Yoh; Yasuda, Susumu; Ishimura, Kosei; Iwata, Nobuhisa; Okamoto, Atsushi; Sato, Yoichi; Ogawa, Mina; Sawada, Makoto; Kawano, Taro; Obara, Shin’ya; Natsukari, Chikara; Wada, Atsushi; Yamada, S.; Fujimoto, R.; Kokubun, M.; Yamasaki, Noriko Y.; Sugita, Hiroyuki; Minesugi, Kenji; Nakamura, Yasuo; Mitsuda, Kazuhisa; Takahashi, Tadayuki; Yoshida, Seiji; Tsunematsu, Shoji; Kanao, Kenichi; Narasaki, Katsuhiro; Otsuka, Kiyomi; Porter, F. S.; Kilbourne, C. A.; Chiao, Meng P.; Eckart, Megan E.; Sneiderman, Gary A.; Pontius, James T.; McCammon, D.; Wilke, Paul S.; Basile, John

doi:10.1117/1.jatis.4.1.011216

Cited by 17 publications

(8 citation statements)

References 19 publications

(15 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This requirement is based on the experience of the Hitomi X-ray satellite. 41 13. The detector yield including the readout electronics is larger than 80 %.…”

Section: Lft Focal Planementioning

confidence: 99%

Concept design of low frequency telescope for CMB B-mode polarization satellite LiteBIRD

Sekímoto

Ade

Adler

et al. 2020

Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy X

Self Cite

View full text Add to dashboard Cite

LiteBIRD has been selected as JAXA's strategic large mission in the 2020s, to observe the cosmic microwave background (CMB) B-mode polarization over the full sky at large angular scales. The challenges of LiteBIRD are the wide field-of-view (FoV) and broadband capabilities of millimeter-wave polarization measurements, which are derived from the system requirements. The possible paths of stray light increase with a wider FoV and the far sidelobe knowledge of −56 dB is a challenging optical requirement. A crossed-Dragone configuration was chosen for the low frequency telescope (LFT : 34-161 GHz), one of LiteBIRD's onboard telescopes. It has a wide field-of-view (18 • × 9 • ) with an aperture of 400 mm in diameter, corresponding to an angular resolution of about 30 arcminutes around 100 GHz. The focal ratio f/3.0 and the crossing angle of the optical axes of 90 • are chosen after an extensive study of the stray light. The primary and secondary reflectors have rectangular shapes with serrations to reduce the diffraction pattern from the edges of the mirrors. The reflectors and structure are made of aluminum to proportionally contract from warm down to the operating temperature at 5 K. A 1/4 scaled model of the LFT has been developed to validate the wide field-of-view design and to demonstrate the reduced far sidelobes. A polarization modulation unit (PMU), realized with a half-wave plate (HWP) is placed in front of the aperture stop, the entrance pupil of this system. A large focal plane with approximately 1000 AlMn TES detectors and frequency multiplexing SQUID amplifiers is cooled to 100 mK. The lens and sinuous antennas have broadband capability. Performance specifications of the LFT and an outline of the proposed verification plan are presented.

show abstract

“…This requirement is based on the experience of the Hitomi X-ray satellite. 41 13. The detector yield including the readout electronics is larger than 80 %.…”

Section: Lft Focal Planementioning

confidence: 99%

Concept design of low frequency telescope for CMB B-mode polarization satellite LiteBIRD

Sekímoto

Ade

Adler

et al. 2020

Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy X

Self Cite

View full text Add to dashboard Cite

show abstract

“…The SXS dewar was in its final flight configuration, following the installation of the isolators between the dewar and the cryocoolers. 44 Figure 17 shows a photo of the experimental setup, and Table 7 lists key instrument parameters. We used the RTS positioned above the dewar to provide x-ray lines at known energies from 4.5 to 13.5 keV.…”

Section: Details Of Gain Scale Calibration Data Acquisitionmentioning

confidence: 99%

“…For the case of the anti-co gain measurement, we used the RTS in nonrotating mode to provide a constant flux of x-rays at 22.105 keV (Ag Kα 12 ) and 24.94 keV (Ag Kβ) for a total of 1.5 h. The instrument was in a nominal operating state with a detector temperature of 50 mK and an anti-co bias of 6 V for each channel. These data were acquired prior to installation of the isolators between the dewar and the cryocoolers, 44 but this difference should not affect the anti-co gain.…”

Section: Anti-coincidence Detector Calibrationmentioning

confidence: 99%

Ground calibration of the Astro-H (Hitomi) soft x-ray spectrometer

Eckart

Adams

Boyce

et al. 2018

J. Astron. Telesc. Instrum. Syst.

Self Cite

View full text Add to dashboard Cite

Ground calibration of the Astro-H (Hitomi) soft x-ray spectrometer," J. Astron. Telesc.Abstract. The Astro-H (Hitomi) Soft X-ray Spectrometer (SXS) was a pioneering imaging x-ray spectrometer with 5 eV energy resolution at 6 keV. The instrument used a microcalorimeter array at the focus of a highthroughput soft x-ray telescope to enable high-resolution nondispersive spectroscopy in the soft x-ray waveband (0.3 to 12 keV). We present the suite of ground calibration measurements acquired from 2012 to 2015, including characterization of the detector system, anti-coincidence detector, optical blocking filters, and filter-wheel filters. The calibration of the 36-pixel silicon thermistor microcalorimeter array includes parameterizations of the energy gain scale and line-spread function for each event grade over a range of instrument operating conditions, as well as quantum efficiency measurements. The x-ray transmission of the set of five Al/polyimide thin-film optical blocking filters mounted inside the SXS dewar has been modeled based on measurements at synchrotron beamlines, including with high spectral resolution at the C, N, O, and Al K-edges. In addition, we present the x-ray transmission of the dewar gate valve and of the filters mounted on the SXS filter wheel (external to the dewar), including beryllium, polyimide, and neutral density filters.

show abstract

“…The SXS has the largest effective area above approximately 0.6 keV, giving a high sensitivity to faint X-ray sources. Kilborne et al (2017aKilborne et al ( , 2017b, Takei et al (2017), Ishisaki et al (2017), Porter et al (2017, Shirron et al (2018), Meng et al (2018), Leutenegger et al (2018), Sneiderman et al (2018).…”

Section: Comparison With Past X-ray Detectorsmentioning

confidence: 99%

High-resolution X-ray spectroscopy of astrophysical plasmas with X-ray microcalorimeters

Ezoe

Ohashi

Mitsuda

2021

Rev. Mod. Plasma Phys.

View full text Add to dashboard Cite

High spectral resolution with a resolving power, $$E/\Delta E \gtrsim 1000$$ E / Δ E ≳ 1000 at 6 keV, is now available in X-ray astronomy. X-ray observations are particularly effective for plasma studies since major atomic transitions appear as spectral features in the X-ray band. High-resolution spectroscopy enables us to probe a wide variety of astrophysical plasmas, which are not obtainable from ground experiments, regarding their temperature, density, magnetic field, gravity, and velocity. In this review, we describe what are the X-ray emitting plasmas in the Universe, along with basic plasma diagnostics, and depict historical development of the techniques used for the X-ray spectroscopy. We outline the X-ray microcalorimeter instrument, soft X-ray spectrometer (SXS), onboard the ASTRO-H satellite. Despite the short lifetime of the satellite in orbit for about a month, observations with the SXS have shown the remarkable power of high-resolution spectroscopy in X-ray astronomy. Observed spectrum of the hot plasma in the core region of the Perseus cluster showed He-like Fe K-line to be clearly resolved into resonance, forbidden and intercombination lines for the first time. The line width indicates that the turbulent pressure amounts to only 4% of the thermal pressure of the plasma. We also describe new findings and constraints obtained from the superb spectrum of the Perseus cluster, which all indicate a great potential of X-ray spectroscopy. The recovery of the spectroscopy science of ASTRO-H is aimed at with XRISM, a Japanese mission planned for launch in early 2020s. In further future, Athena will expand the rich science with its high sensitivity and spectral resolution in early 2030s.

show abstract

Vibration isolation system for cryocoolers of soft x-ray spectrometer on-board ASTRO-H (Hitomi)

Cited by 17 publications

References 19 publications

Concept design of low frequency telescope for CMB B-mode polarization satellite LiteBIRD

Concept design of low frequency telescope for CMB B-mode polarization satellite LiteBIRD

Ground calibration of the Astro-H (Hitomi) soft x-ray spectrometer

High-resolution X-ray spectroscopy of astrophysical plasmas with X-ray microcalorimeters

Contact Info

Product

Resources

About