Date and Time of the Query: 2019-05-21 T02:09:27 PDT
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Notes for object [HB89] 0957+561

5 note(s) found in NED.

1. 2008MNRAS.387.1303S
Re:[HB89] 0957+561
4.1.2 Q0957+561 - The gravitational lens Q0957+561 is the most thoroughly
studied one in literature. The system involves a radio-loud quasar at redshift
z_s_ = 1.41 which is mapped into two images by a brightest cluster galaxy and
its parent cluster at redshift z_l_ = 0.36 (e.g. Keeton et al. 2000; Barkana et
al. 1999, and references therein). It is also known that the lens galaxy has a
small ellipticity gradient and isophote twist which are properties the simple HK
model cannot account for. Together with the fact that the lens is embedded into
a cluster, this might be a reason for the huge discrepancy between observed and
predicted flux ratio in the context of modified gravity.

2. 2002ApJS..140..143B
Re:[HB89] 0957+561
q0957+5608B, z = 1.414.-See notes for q0957+5608A. G270, G190.

3. 2000MNRAS.311..456M
Re:RX J100120.3+555349
RX J100120.3+555349: Gravitationally lensed quasar [HB89] 0957+561
(Hewitt & Burbidge 1989). Considered as a single X-ray source.

4. 1995A&AS..110..213R
Re:[HB89] 0957+561
0957+561: This is the famous double quasar (gravitational lens system)
discovered by Walsh et al. (1979). The 5 GHz map shown here was made from
2 minutes of data. The best published map is that of Roberts et al.(1985).

5. 1992MNRAS.256..589P
Re:E 0957+561
E0957+561*, z = 1.41. This radio-selected object is a gravitationally
lensed double quasar and is variable (See HB). A detailed discussion of
its soft X-ray emission may be found in C92. It has a high redshift and
no hard X-ray component is detected in the C3 band. The optical power-law
index is steep ({alpha}_opt_ = 0.3) and Mg II {lambda}{lambda}2798 is
weak and broad with absorption features either side. The C III]{lambda}1908
line is broad and stronger than Mg II, and may be blended with underlying
Fe II emission. There is evidence of a strong and narrow C IV {lambda}
1548 line, but it lies in the noise at the blue end of the spectrum. The
two spectra were resolved by Wills & Wills (1980]; both spectra show Mg
II {lambda}2798 as strong as C III]{lambda} 1908 and the lines have
similar profiles, but the continua are flatter than seen in the USS
spectrum and rise to the red.
* = secure USS AGN

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