Temperature structure of the high-latitude corona

被引:16
作者
Guhathakurta, M
Fisher, R
Strong, K
机构
[1] LOCKHEED PALO ALTO RES LABS,LOCKHEED MARTIN SOLAR & ASTROPHYS LAB,PALO ALTO,CA 94304
[2] CATHOLIC UNIV AMER,DEPT PHYS,WASHINGTON,DC 20064
基金
美国国家航空航天局;
关键词
Sun; corona;
D O I
10.1086/310316
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
This Letter explores the physical and morphological characteristics of the large-scale coronal structures such as polar coronal rays and high-latitude streamers as seen in white light and relates these structures to observations in soft X-ray (3-45 Angstrom) and red (Fex lambda 6374) and green (Ferry lambda 5303) line emissions to estimate their temperatures. Analysis shows that polar rays can be characterized by at least two temperature classes: Cool (0.7-1.3 x 10(6) K) rays are a dominant feature of the polar corona during the quiescent phase of the solar cycle. The hot (1.8-2.6 x 10(6) K) rays, when present, form a small subset of the array of rays seen in white light. Hot rays seem to emerge from the boundary of the polar coronal hole (polar crown filament belt). The location of the cool rays, on the other hand, can be on the boundary or inside the coronal hole. We do not always find a one-to-one correspondence between the polar rays observed in white light versus those observed in XUV and visible emission lines. We find the emission-line ratio temperature to be high in the high-latitude (>45 degrees) coronal streamers with enhanced white-light emission. These streamers are located along a neutral line that separates the weak, old-cycle polar field from the weak, new-cycle high-latitude magnetic field of opposite polarity.
引用
收藏
页码:L69 / &
页数:6
相关论文
共 9 条
[1]  
FISHER RR, 1995, APJ, V447, P139
[2]   CORONAL DENSITY AND TEMPERATURE STRUCTURE FROM COORDINATED OBSERVATIONS ASSOCIATED WITH THE TOTAL SOLAR ECLIPSE OF 1988 MARCH 18 [J].
GUHATHAKURTA, M ;
ROTTMAN, GJ ;
FISHER, RR ;
ORRALL, FQ ;
ALTROCK, RC .
ASTROPHYSICAL JOURNAL, 1992, 388 (02) :633-643
[3]   LARGE-SCALE CORONAL TEMPERATURE AND DENSITY DISTRIBUTIONS, 1984-1992 [J].
GUHATHAKURTA, M ;
FISHER, RR ;
ALTROCK, RC .
ASTROPHYSICAL JOURNAL, 1993, 414 (02) :L145-&
[4]  
GUHATHAKURTA M, 1995, BAAS, V27, P2961
[5]  
GUHATHAKURTA M, 1996, IN PRESS AIP C P SOL
[6]  
HABBAL SR, 1995, GEOPHYS RES LETT, V22, P1465, DOI 10.1029/95GL01064
[7]  
HARA H, 1994, PUBL ASTRON SOC JPN, V46, P493
[8]  
SMARTT RN, 1982, P SOC PHOTO-OPT INS, V336, P454
[9]   THE SOFT-X-RAY TELESCOPE FOR THE SOLAR-A MISSION [J].
TSUNETA, S ;
ACTON, L ;
BRUNER, M ;
LEMEN, J ;
BROWN, W ;
CARAVALHO, R ;
CATURA, R ;
FREELAND, S ;
JURCEVICH, B ;
MORRISON, M ;
OGAWARA, Y ;
HIRAYAMA, T ;
OWENS, J .
SOLAR PHYSICS, 1991, 136 (01) :37-67