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تسجيل مستخدم جديدVLT adaptive optics imaging of QSO host galaxies and close environment at z ~2.5: results from a pilot program
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R. Falomo
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We report ESO-VLT near-infrared adaptive optics imaging of one radio-loud (PKS 0113-283) and two radio-quiet (Q 0045-3337 and Q 0101-337) QSOs at z > 2. In the first case, we are able to resolve the QSO and find that it is hosted by an elliptical of absolute magnitude M(K) = -27.6. For the other two objects, no extended emission has been unambiguously detected. This result, though restricted to a single object, extends up to z ~2.5 the finding that cosmic evolution of radio-loud QSO hosts follows the trend expected for luminous and massive spheroids undergoing passive evolution. For Q 0045-3337, our high resolution images show that it is located 1.2 arcsec from a K = 17.5 foreground disc galaxy, which may act as a gravitational lens, since the QSO most probably lies within the galaxy Einstein radius.
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We report near-infrared (primarily H-band) adaptive optics (AO) imaging with the Gemini-N and Subaru Telescopes, of a representative sample of 32 nearby (z<0.3) QSOs selected from the Palomar-Green (PG) Bright Quasar Survey (BQS), in order to investi
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