The time-resolved soft x-ray spectrometer (TSXS) aboard on the X-ray Pulsar Navigation Test Satellite is an x-ray timing spectrometer covering the energy range of 0.5 to 10 keV. It is China’s first focusing x-ray telescope launched into space orbit. The optical system of TSXS is an x-ray grazing incidence focusing system with a field of view 15 arc min, which is nested with 4 parabolic mirrors with a focal length of 1150 mm. The focal plane detector of TSXS uses a silicon drift detector. From April to June 2016, ground calibration was carried out on TSXS, including the optical axis determination, calibration of energy linearity and energy resolution, calibration of time resolution and photon arrival time accuracy, and calibration of mirrors’ reflectivity. After the launch on November 10, 2016, the in-orbit calibration and performance verification of the telescope was carried out, including the optical axis determination, the performance of energy response, the performance of time accuracy, the calibration of effective area, and the evaluation of telescope sensitivity. After calibration and verification on the ground and in orbit, the photon energy measurement error of the telescope is better than 0.5% at energies above 1.5 keV, the energy resolution is better than 156 eV at 6.4 keV, the time resolution is <1 μs, the photon arrival time measurement accuracy is <302 ns, and the telescope in-orbit background is <4.16 ± 1.42 × 10 − 3 photons / s (0.5 to 3 keV, 40°N to 40°S, not including South Atlantic Anomaly). The telescope has an in-orbit observation sensitivity of 2.09 × 10 − 3 photons / cm2 / s / keV (0.5 to 3 keV, T = 1000 s, and nσ = 5).
The grazing incidence soft X-ray optical system is the core equipment of future space science missions. The optical system expands the collecting area of x-ray photos and improves the SNR. The effective area calibration is the key indicator for testing and verifying the performance of the grazing incidence optical system. One of the traditional calibration methods uses the wide x-ray beam as the calibration x-ray source. This calibration method requires large ground equipment, high environmental conditions while the x-ray beam is not so parallel that the calibration accuracy is limited. Another effective area calibration method uses the narrow x-ray beam scan the optical system. In this paper, the above two effective area calibration methods of the grazing incidence optical system are modeled mathematically. The factors such as the parallelism of the beam, the uniformity of the beam and the characteristics of optical system are absorbed into the unified mathematical model for describing the effective area. The key factors which affect the effective area calibration accuracy are extracted, and their influences on the calibration result are analyzed. Eventually the two calibration methods accuracy is evaluated and the ways for improving the calibration accuracy are given. The effective area calibration is able to test and verify the collecting ability of x-ray photons of the grazing incidence optical system, which is the basis for the development of soft x-ray optics.
X-ray pulsar navigation has attracted extensive attentions from academy and engineering domains. The navigation accuracy is can be enhanced through design of X-ray mirrors to focus X-rays to a small detector. The Wolter-I optics, originally proposed based on a paraboloid mirror and a hyperboloid mirror for X-ray imaging, has long been widely developed and employed in X-ray observatory. Some differences, however, remain in the requirements on optics between astronomical X-ray observation and pulsar navigation. The simplified Wolter-I optics, providing single reflection by a paraboloid mirror, is more suitable for pulsar navigation. In this paper, therefore, the grazing incidence X-ray mirror was designed further based on our previous work, with focus on the reflectivity, effective area, angular resolution and baffles. To evaluate the performance of the manufactured mirror, the surface roughness and reflectivity were tested. The test results show that the grazing incidence mirror meets the design specifications. On the basis of this, the reflectivity of the mirror in the working bandwidth was extrapolated to evaluate the focusing ability of the mirror when it works together with the detector. The purpose of our current work to design and develop a prototype mirror was realized. It can lay a foundation and provide guidance for the development of multilayer nested X-ray mirror with larger effective area.
In order to satisfy the reliability demand of the long-life satellite, and solve the weak link, we design an kind of the long service life integration CES (LFICES). In order to solve the problem from the late resistance increased product life, we perform the high torque motor technology research. Then we performed the accelerated life test of the rotating device. In the accelerated life test, we simulated operation of eight years, and the test results showed that the rotating device meet the design requirements of eight years. In this paper, we gives the design scheme of the LFICES. The telemetering data of the 26th remote sensing satellite in-orbit flight shows that the LFICES can stably work．
X-ray pulsar telescope (XPT) is a complex optical payload, which involves optical, mechanical, electrical and thermal disciplines. The multiphysics coupling analysis (MCA) plays an important role in improving the in-orbit performance. However, the conventional MCA methods encounter two serious problems in dealing with the XTP. One is that both the energy and reflectivity information of X-ray can’t be taken into consideration, which always misunderstands the essence of XPT. Another is that the coupling data can’t be transferred automatically among different disciplines, leading to computational inefficiency and high design cost. Therefore, a new MCA method for XPT is proposed based on the Monte Carlo method and total reflective theory. The main idea, procedures and operational steps of the proposed method are addressed in detail. Firstly, it takes both the energy and reflectivity information of X-ray into consideration simultaneously. And formulate the thermal-structural coupling equation and multiphysics coupling analysis model based on the finite element method. Then, the thermalstructural coupling analysis under different working conditions has been implemented. Secondly, the mirror deformations are obtained using construction geometry function. Meanwhile, the polynomial function is adopted to fit the deformed mirror and meanwhile evaluate the fitting error. Thirdly, the focusing performance analysis of XPT can be evaluated by the RMS. Finally, a Wolter-I XPT is taken as an example to verify the proposed MCA method. The simulation results show that the thermal-structural coupling deformation is bigger than others, the vary law of deformation effect on the focusing performance has been obtained. The focusing performances of thermal-structural, thermal, structural deformations have degraded 30.01%, 14.35% and 7.85% respectively. The RMS of dispersion spot are 2.9143mm, 2.2038mm and 2.1311mm. As a result, the validity of the proposed method is verified through comparing the simulation results and experiments, which can be employed in the reliability-based design of XPT.
We have developed X-ray grazing incidence optics with a single mirror. Although t can be used to demonstrate and test on
the ground to verify the feasibility of X-ray detection system, it is unable to meet the requirements of X-ray pulsar
navigation due to small effective area and large mass. There is an urgent need to develop multilayer nested grazing
incidence optics, which consists of multilayer mirrors to form a coaxial and confocal system to maximize the use of space
and increase the effective area.
In this paper, aiming at the future demand of X-ray pulsar navigation, optimization and analysis of nested X-ray grazing
incidence optics was carried out, the recurrence relations between the layers of mirrors were derived, reasonable initial
structural parameters and stray light reduction method was given, and theoretical effective collection area was calculated.
The initial structure and stray light eliminating structure are designed. The optical-mechanical-thermal numerical model
was established using optical analysis software and finite element software for stray light analysis, focusing performance
analysis, tolerance analysis, and mechanical analysis, providing evidence and guidance for the processing and alignment of
nested X-ray grazing incidence optics.
When the moon and the sun light enter into the field of view of the conical scanning earth sensor (CES), the real attitude of the spacecraft will be affected because of wrong CES measurements．To solve this problem, a new method based on the CES software can discriminate the interference effect．A series of ground are designed to verify this method effectiveness, and results indicate that this method can not only give a indication of the moon, but also can eliminate effect of the moon and the sun light on the CES’s measurements．Finally, the on-orbit flight data is presented to confirm this method validity．
Climate Modeling results show that about 50% of the Earth’s outgoing radiation and 75% of the atmospheric
outgoing radiation are contained in the far infrared. Generally the earth is considered as a 220~230 K blackbody, and the
peak breadth of the Earth’s outgoing radiation is around the wavelength of 10 micron. The atmospheric outgoing
radiation are contained with five spectral intervals: the water vapor band from 6.33 to 6.85 microns, the ozone band from
8.9 to 10.1microns, the atmospheric window from 10.75 to 11.75 microns, the carbon dioxide band from 14 to 16
microns, and finally the rotational water vapor band from 21 to 125 microns. The properties of the carbon dioxide band
is stable than other bands which has been chosen for the work Spectrum of the earth sensors. But the radiation energy of
carbon dioxide band is variety and it is a function of latitude, season and weather conditions. Usually the luminance of
the Earth’s radiation (14 to 16 μm) is from 3 to 7 W/m2Sr.
Earth sensor is an important instrument of the Attitude and Orbit Control System (AOCS), and it is sensitive to the curve
of the earth’s and atmospheric outgoing radiation profile to determine the roll and pitch angles of satellite which are
relative to nadir vector. Most earth sensors use profile data gathered form Project Scanner taken in August and December
The earth sensor referred in this paper is the conical scanning earth sensor which is mainly used in the LEO (Low Earth
Orbit) satellite. A method to determine the luminance of earth’s and atmospheric outgoing radiation (carbon dioxide)
using the earth sensor is discussed in this paper. When the conical scanning sensor scan form the space to the earth, a
pulse is produced and the pulse breadth is scale with the infrared radiation luminance. Then the infrared radiation
luminance can be calculated. A carbon dioxide radiance model of the earth’s and atmospheric outgoing radiation is
obtained according the luminance data about with different latitudes and seasons which are measured form the conical
scanning earth sensors of ZY-1 satellite.
When the carbon dioxide radiance model has been collected, it can be fed directly to the earth sensors to improve their
accuracy. It also can be supplied for the research of the content and distribution of carbon dioxide in the atmosphere.