AN OBSERVATIONAL STUDY OF MILLIMETER-WAVE RECOMBINATION LINES

被引：26

作者：

GORDON, MA ^{[1
]}

WALMSLEY, CM ^{[1
]}

机构：

[1] MAX PLANCK INST RADIOASTRON,W-5300 BONN 1,GERMANY

来源：

ASTROPHYSICAL JOURNAL | 1990年 / 365卷 / 02期

关键词：

Interstellar: matter; Nebulae: H II regions; Radio sources: lines;

D O I：

10.1086/169514

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We report observations of H36α, He36α, H40α, He40α, H44β He44β, H45β, H50β, H50γ, H56δ, H57γ, and H60ε radio recombination lines in the 2 and 3 mm telluric windows made with the IRAM 30 m telescope on Pico Veleta, Spain. Sources observed were the H II regions W3, NGC 1976, NGC 2024, Sgr B2, M17, W49, and DR 21. The observations are consistent with non-LTE models based upon centimeter-wave observations. The millimeter-wave recombination lines show no substantive indication of excitation by Lyman line radiation from nearby exciting stars so that conventional departure coefficients may be used with confidence. However, small departures from the expected line ratios have been found in some cases which merit additional investigation.

引用

页码：606 / 614

页数：9

共 32 条

[1]

BEIGMAN IL, 1980, 141 LEB PHYS I PREPR

[2]

CHURCHWELL E, 1978, ASTRON ASTROPHYS, V70, P719

[3] STIMULATED EMISSION OF RADIO-FREQUENCY LINES OF HYDROGEN [J].