Calibration of the Surface Brightness Fluctution Method for use with the Hubble Space Telescope.

1997 ◽  
Vol 114 ◽  
pp. 626 ◽  
Author(s):  
Edward A. Ajhar ◽  
Tod R. Lauer ◽  
John L. Tonry ◽  
John P. Blakeslee ◽  
Alan Dressler ◽  
...  
2001 ◽  
Vol 18 (2) ◽  
pp. 182-185
Author(s):  
Geraint F. Lewis

AbstractThe true nature of dark matter in the universe still eludes us. This paper discusses a new test for the detection of stellar mass compact dark matter in galaxy clusters by observing its gravitational lensing influence on the surface brightness of giant luminous arcs. If dark matter is in the form of stellar mass compact objects, then the extremes of such variability are accessible to a monitoring campaign with the Hubble Space Telescope. With the advent of the Next Generation Space Telescope, cluster dark matter in the form of compact objects will induce a ubiquitous ‘shimmering’ of the giant arcs.


2020 ◽  
Vol 495 (3) ◽  
pp. 3192-3208
Author(s):  
Liang Dai ◽  
Alexander A Kaurov ◽  
Keren Sharon ◽  
Michael Florian ◽  
Jordi Miralda-Escudé ◽  
...  

ABSTRACT We study the highly magnified arc SGAS J122651.3+215220 caused by a star-forming galaxy at zs = 2.93 crossing the lensing caustic cast by the galaxy cluster SDSS J1226+2152 (zl = 0.43), using Hubble Space Telescope observations. We report in the arc several asymmetric surface brightness features whose angular separations are a fraction of an arcsecond from the lensing critical curve and appear to be highly but unequally magnified image pairs of underlying compact sources, with one brightest pair having clear asymmetry consistently across four filters. One explanation of unequal magnification is microlensing by intracluster stars, which induces independent flux variations in the images of individual or groups of source stars in the lensed galaxy. For a second possibility, intracluster dark matter subhaloes invisible to telescopes effectively perturb lensing magnifications near the critical curve and give rise to persistently unequal image pairs. Our modelling suggests, at least for the most prominent identified image pair, that the microlensing hypothesis is in tension with the absence of notable asymmetry variation over a six-year baseline, while subhaloes of ∼106–$10^8\, \mathrm{ M}_\odot$ anticipated from structure formation with cold dark matter typically produce stationary and sizable asymmetries. We judge that observations at additional times and more precise lens models are necessary to stringently constrain temporal variability and robustly distinguish between the two explanations. The arc under this study is a scheduled target of a Director’s Discretionary Early Release Science program of the James Webb Space Telescope, which will provide deep images and a high-resolution view with integral field spectroscopy.


1993 ◽  
Vol 155 ◽  
pp. 499-499
Author(s):  
Howard E. Bond ◽  
Michael G. Meakes ◽  
James W. Liebert ◽  
Alvio Renzini

This paper deals with the central stars of two large, low-surface-brightness planetary nebulae: V605 Aquilae, central star of Abell 58, and 0950+139, central star of EGB 6. Both of these nuclei are associated with compact emission-line nebulosities, which are unresolved from the ground. We obtained images with the Faint Object Camera (FOC) on the Hubble Space Telescope of both objects, in order to determine the nature of the compact nebulae.


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