Old problems found anew
نویسندگان
چکیده
منابع مشابه
Found by an Old Einstein
We obtained new ROSAT HRI and optical observations in the field of the Einstein X-ray source E 0336–248, which we use to identify it as a 19th magnitude BL Lacertae object at z = 0.251 with LX = 1× 10 45 erg s. It is also a 14 mJy radio source at 20 cm. An emission-line galaxy at z = 0.043 that was previously considered a Seyfert identification for E 0336–248 is shown instead to be an unrelated...
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ژورنال
عنوان ژورنال: Nature
سال: 1984
ISSN: 0028-0836,1476-4687
DOI: 10.1038/310616b0