Results 191 to 200 of about 512 (214)

Automation of finding strong gravitational lenses in the Kilo Degree Survey with U - DenseLens (DenseLens  + Segmentation). [PDF]

Mon Not R Astron Soc
N BC, Koopmans LVE, Valentijn EA, Kleijn GV, de Jong JTA, Napolitano N, Li R, Tortora C, Busillo V, Dong Y.   +9 more
europepmc   +1 more source

Primordial black holes and their gravitational-wave signatures. [PDF]

Living Rev Relativ
Bagui E, Clesse S, De Luca V, Ezquiaga JM, Franciolini G, García-Bellido J, Joana C, Kumar Jain R, Kuroyanagi S, Musco I, Papanikolaou T, Raccanelli A, Renaux-Petel S, Riotto A, Ruiz Morales E, Scalisi M, Sergijenko O, Ünal C, Vennin V, Wands D, LISA Cosmology Working Group.   +20 more
europepmc   +1 more source

Some of the next articles are maybe not open access.

Related searches:

Quasars: Double Darkness in Draco

Science, 1993
Ray Jayawardhana
exaly   +3 more sources

VLA Observations of the Double Quasar 0957+561: Gravitational Double Image or Binary Quasar?

Symposium - International Astronomical Union, 1980
The radio source 0957+561 was identified by Walsh et al. (1979, Nature 279, pp.381–384) with a pair of quasars, 6.1 apart on the sky, whose optical emission and absorption spectra are nearly identical. Walsh et al. suggested a gravitational lens interpretation in which a single object is split into two images by an intervening massive object. Using the
D. H. Roberts, P. E. Greenfield, B. F. Burke   +2 more
openaire   +1 more source

A Cosmic Double Helix in the Archetypical Quasar 3C273

Science, 2001
Finding direct evidence for plasma instability in extragalactic jets is crucial for understanding the nature of relativistic outflows from active galactic nuclei. Our radio interferometric observations of the quasar 3C273 made with the orbiting radio telescope, HALCA, and an array of ground telescopes have yielded an image in which the emission across ...
A P, Lobanov, J A, Zensus
openaire   +2 more sources

Radio structure of the ‘double quasar’ 4C11.50

Nature, 1974
WAMPLER et al.1 have recently announced the discovery of a close pair of optical quasars associated with the radio source 4C11.50. The brighter quasar (a) has a redshift of 0.436, whereas its companion (b), 4.8 arc s away in position angle 95°, has a much larger redshift of 1.901.
D. STANNARD, P. N. WILKINSON, R. S. WARWICK, R. J. DAVIS   +3 more
openaire   +1 more source

Superluminal motion in the double-lobed quasar 3C263

Nature, 1987
The detection of superluminal motion in the quasar 3C263 is reported. The milliarcsecond structure of this source consists of two nearly unresolved components whose separation is increasing at a rate of 0.06 + or - 0.02 marcsec/yr. This corresponds to an expansion speed of 2.7 + or - 0.9 c (H/0/ = 55 km/s/Mpc, q/0/ = 0.05).
J. A. Zensus, D. H. Hough, R. W. Porcas
openaire   +1 more source

Variability of the double quasar 0957 + 561 A, B

Nature, 1981
Evidence suggests that the double nature of the quasar 0957 + 561 A, B results from the influence of an intervening gravitational lens on the light from a more distant, single quasar. The nearly identical spectral characteristics of the two objects have been established1–3 and have been the incentive for interpreting the two apparent objects as images ...
Joseph S. Miller, Robert R. J. Antonucci, William C. Keel   +2 more
openaire   +1 more source

Quasar image doubling associated with absorption systems

Nature, 1979
Ever since their discovery the origin of quasar absorption lines has been a subject of considerable controversy (see ref. 1). In this note we consider the consequences of the hypothesis that at least some of the absorption lines arise in galaxies. These galaxies could be ordinary ones with 50–100 kpc haloes2, or perhaps more compact but more common (at
Julian H. Krolik, John Kwan
openaire   +1 more source

Ton 155 and 156: a Double Quasar?

Nature Physical Science, 1972
Janes and Lynds1 have shown that Ton 156 is a quasar, although they were unable to determine a satisfactory redshift. My spectroscopic observations made with the Mauna Kea 224 cm telescope, have shown that Ton 155, located at about 35″ arc north preceding Ton 156, is also a quasar and have allowed redshifts to be determined for both objects.
openaire   +1 more source