Improvement of Yohkoh hard x-ray imaging

被引：43

作者：

Sato, J ^{[1
]}

Kosugi, T

Makishima, K

机构：

[1] Nobeyama Radio Observ, Minamisa Ku, Nagano 3841305, Japan

[2] Univ Tokyo, Sch Sci, Dept Phys, Bunkyo Ku, Tokyo 1130033, Japan

来源：

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN | 1999年 / 51卷 / 01期

关键词：

image processing; instruments; sun : flares; sun : X-rays;

D O I：

10.1093/pasj/51.1.127

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

The Hard X-ray Telescope (HXT) on board Yohkoh is a Fourier-synthesis-type imager for solar flare observations; it measures a set of spatially modulated photon counts with sixty-four, independent, bigrid modulation collimators and an image is reconstructed from these data using sophisticated image synthesis procedures, such as the Maximum Entropy Method (MEM) and PIXON. The HXT-MEM imaging has been greatly improved by incorporating the following three improvements which we have recently achieved: (1) Accurately estimated instrumental response functions (X-ray transmission/modulation patterns), which are made available through self-calibration using solar flares as calibration sources; (2) Improvement of the MEM algorithm, which includes the total flux estimate in its iteration loop; and (3) Accurate error estimate and its proper inclusion in the MEM. Various problems seen in previous HXT-MEM imaging are drastically reduced and high-quality images are obtained.

引用

页码：127 / 150

页数：24

共 20 条

[1] A spectral analysis of the Masuda flare using Yohkoh hard X-ray telescope pixon reconstruction [J].

Alexander, D ;

Metcalf, TR .

ASTROPHYSICAL JOURNAL, 1997, 489 (01) :442-455

[2]

BRADT H, 1968, SPACE SCI REV, V8, P471, DOI 10.1007/BF00175003

[3]

DOTANI T, 1986, THESIS U TOKYO

[4] RESTORING WITH MAXIMUM LIKELIHOOD AND MAXIMUM ENTROPY [J].

FRIEDEN, BR .

JOURNAL OF THE OPTICAL SOCIETY OF AMERICA, 1972, 62 (04) :511-&

[5] IMAGE-RECONSTRUCTION FROM INCOMPLETE AND NOISY DATA [J].

GULL, SF ;

DANIELL, GJ .

NATURE, 1978, 272 (5655) :686-690

[6]

Hogbom J. A., 1974, Astronomy and Astrophysics Supplement Series, V15, P417

[7]

INDA M, 1991, THESIS U TOKYO

[8]

INDAKOIDE M, 1994, THESIS U TOKYO

[9] THE HARD X-RAY TELESCOPE (HXT) FOR THE SOLAR-A MISSION [J].

KOSUGI, T ;

MAKISHIMA, K ;

MURAKAMI, T ;

SAKAO, T ;

DOTANI, T ;

INDA, M ;

KAI, K ;

MASUDA, S ;

NAKAJIMA, H ;

OGAWARA, Y ;

SAWA, M ;

SHIBASAKI, K .

SOLAR PHYSICS, 1991, 136 (01) :17-36

[10]

KOSUGI T, 1992, PUBL ASTRON SOC JPN, V44, pL45

← 1 2 →