Morphology & Kinematics of the ‘Born–Again’ Planetary Abell 78
نویسندگان
چکیده
منابع مشابه
Physical conditions in the planetary nebula Abell 30
We have analysed optical spectra of two of the hydrogen-deficient knots (J1 & J3) in the born-again planetary nebula Abell 30, together with UV spectra of knots J3 & J4. We determine electron temperatures in the knots based on several diagnostics. The [O III] nebular-toauroral transition ratio yields temperatures of the order of 17 000 K. The weak temperature dependence of the ratios of helium ...
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ژورنال
عنوان ژورنال: Symposium - International Astronomical Union
سال: 1993
ISSN: 0074-1809
DOI: 10.1017/s0074180900171773