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1.
The X-Ray Telescope (XRT) onboard the Hinode satellite is an X-ray imager that observes the solar corona with unprecedentedly high angular resolution (consistent with its 1?? pixel size). XRT has nine X-ray analysis filters with different temperature responses. One of the most significant scientific features of this telescope is its capability of diagnosing coronal temperatures from less than 1 MK to more than 10 MK, which has never been accomplished before. To make full use of this capability, accurate calibration of the coronal temperature response of XRT is indispensable and is presented in this article. The effect of on-orbit contamination is also taken into account in the calibration. On the basis of our calibration results, we review the coronal-temperature-diagnostic capability of XRT.  相似文献   
2.
The Hard X-ray Telescope (HXT) is a Fourier-synthesis imager; a set of spatially-modulated photon count data are taken from 64 independent subcollimators and are Fourier-transformed into an image by using procedures such as the maximum entropy method (MEM) or CLEAN. The HXT takes images of solar flares simultaneously in four energy bands, nominally 15 (or 19)–24, 24–35, 35–57, and 57–100 keV, with an ultimate angular resolution as fine as 5 arc sec and a time resolution 0.5 s. Each subcollimator has a field of view wider than the solar disk. The total effective area of the collimator/detector system reaches 70 cm2, about one order of magnitude larger than that of the HINOTORI hard X-ray imager. Thanks to these improvements, HXT will for the first time enable us to take images of flares at photon energies above 30 keV. These higher-energy images will be compared with lower-energy ones, giving clues to the understanding of nonthermal processes in solar flares, i.e., the acceleration and confinement of energetic electrons. It is of particular importance to specify the acceleration site with regard to the magnetic field figuration in a flaring region, which will be achieved by collaborative observations between HXT and the Soft X-ray Telescope on board the same mission.After the launch the name of SOLAR-A has been changed to YOHKOH.  相似文献   
3.
We present the results of a detailed analysis of multi-wavelength observations of a very impulsive solar flare 1B/M6.7, which occurred on 10 March, 2001 in NOAA AR 9368 (N27 W42). The observations show that the flare is very impulsive with a very hard spectrum in HXR that reveal that non-thermal emission was most dominant. On the other hand, this flare also produced a type II radio burst and coronal mass ejections (CME), which are not general characteristics for impulsive flares. In H we observed bright mass ejecta (BME) followed by dark mass ejecta (DME). Based on the consistency of the onset times and directions of BME and CME, we conclude that these two phenomena are closely associated. It is inferred that the energy build-up took place due to photospheric reconnection between emerging positive parasitic polarity and predominant negative polarity, which resulted as a consequence of flux cancellation. The shear increased to >80 due to further emergence of positive parasitic polarity causing strongly enhanced cancellation of flux. It appears that such enhanced magnetic flux cancellation in a strongly sheared region triggered the impulsive flare.  相似文献   
4.
The Chromospheric Lyman-Alpha SpectroPolarimeter is a sounding rocket instrument designed to measure for the first time the linear polarization of the hydrogen Lyman-\({\upalpha }\) line (121.6 nm). The instrument was successfully launched on 3 September 2015 and observations were conducted at the solar disc center and close to the limb during the five-minutes flight. In this article, the disc center observations are used to provide an in-flight calibration of the instrument spurious polarization. The derived in-flight spurious polarization is consistent with the spurious polarization levels determined during the pre-flight calibration and a statistical analysis of the polarization fluctuations from solar origin is conducted to ensure a 0.014% precision on the spurious polarization. The combination of the pre-flight and the in-flight polarization calibrations provides a complete picture of the instrument response matrix, and a proper error transfer method is used to confirm the achieved polarization accuracy. As a result, the unprecedented 0.1% polarization accuracy of the instrument in the vacuum ultraviolet is ensured by the polarization calibration.  相似文献   
5.
The Hinode satellite (formerly Solar-B) of the Japan Aerospace Exploration Agency’s Institute of Space and Astronautical Science (ISAS/JAXA) was successfully launched in September 2006. As the successor to the Yohkoh mission, it aims to understand how magnetic energy gets transferred from the photosphere to the upper atmosphere and results in explosive energy releases. Hinode is an observatory style mission, with all the instruments being designed and built to work together to address the science aims. There are three instruments onboard: the Solar Optical Telescope (SOT), the EUV Imaging Spectrometer (EIS), and the X-Ray Telescope (XRT). This paper provides an overview of the mission, detailing the satellite, the scientific payload, and operations. It will conclude with discussions on how the international science community can participate in the analysis of the mission data. T. Kosugi deceased 26 November 2006.  相似文献   
6.
Sakao  T.  Tsuneta  S.  Hara  H.  Shimizu  T.  Kano  R.  Kumagai  K.  Yoshida  T.  Nagata  S.  Kobayashi  K. 《Solar physics》1999,187(2):303-333
  相似文献   
7.
The X-ray Telescope (XRT) aboard the Hinode satellite is a grazing incidence X-ray imager equipped with a 2048×2048 CCD. The XRT has 1 arcsec pixels with a wide field of view of 34×34 arcmin. It is sensitive to plasmas with a wide temperature range from < 1 to 30 MK, allowing us to obtain TRACE-like low-temperature images as well as Yohkoh/SXT-like high-temperature images. The spacecraft Mission Data Processor (MDP) controls the XRT through sequence tables with versatile autonomous functions such as exposure control, region-of-interest tracking, flare detection, and flare location identification. Data are compressed either with DPCM or JPEG, depending on the purpose. This results in higher cadence and/or wider field of view for a given telemetry bandwidth. With a focus adjust mechanism, a higher resolution of Gaussian focus may be available on-axis. This paper follows the first instrument paper for the XRT (Golub et al., Solar Phys. 243, 63, 2007) and discusses the design and measured performance of the X-ray CCD camera for the XRT and its control system with the MDP.  相似文献   
8.
The X-Ray Telescope (XRT) onboard the Hinode satellite is an X-ray imager that observes the solar corona with the capability of diagnosing coronal temperatures from less than 1 MK to more than 10 MK. To make full use of this capability, Narukage et al. (Solar Phys. 269, 169, 2011) determined the thickness of each of the X-ray focal-plane analysis filters based on calibration measurements from the ground-based end-to-end test. However, in their paper, the calibration of the thicker filters for observations of active regions and flares, namely the med-Be, med-Al, thick-Al and thick-Be filters, was insufficient due to the insufficient X-ray flux used in the measurements. In this work, we recalibrate those thicker filters using quiescent active region data taken with multiple filters of XRT. On the basis of our updated calibration results, we present the revised coronal-temperature-diagnostic capability of XRT.  相似文献   
9.
The X-ray Telescope (XRT) of the Hinode mission provides an unprecedented combination of spatial and temporal resolution in solar coronal studies. The high sensitivity and broad dynamic range of XRT, coupled with the spacecraft’s onboard memory capacity and the planned downlink capability will permit a broad range of coronal studies over an extended period of time, for targets ranging from quiet Sun to X-flares. This paper discusses in detail the design, calibration, and measured performance of the XRT instrument up to the focal plane. The CCD camera and data handling are discussed separately in a companion paper.  相似文献   
10.
Yohkoh observations of an impulsive solar flare which occurred on 16 December, 1991 are presented. This flare was a GOES M2.7 class event with a simple morphology indicative of a single flaring loop. X-ray images were taken with the Hard X-ray Telescope (HXT) and soft X-ray spectra were obtained with the Bragg Crystal Spectrometer (BCS) on board the satellite. The spectrometer observations were made at high sensivity from the earliest stages of the flare, are continued throughout the rise and decay phases, and indicate extremely strong blueshifts, which account for the majority of emission in Caxix during the initial phase of the flare. The data are compared with observations from other space and ground-based instruments. A balance calculation is performed which indicates that the energy contained in non-thermal electrons is sufficient to explain the high temperature plasma which fills the loop. The cooling of this plasma by thermal conduction is independently verified in a manner which indicates that the loop filling factor is close to 100%. The production of superhot plasma in impulsive events is shown to differ in detail from the morphology and mechanisms appropriate for more gradual events.  相似文献   
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