THE HUBBLE CONSTANT INFERRED FROM 18 TIME-DELAY LENSES
نویسندگان
چکیده
منابع مشابه
The Hubble Constant from (CLASS) Gravitational Lenses
One of the main objectives of the Cosmic Lens All-Sky Survey (CLASS) collaboration has been to find gravitational lens (GL) systems at radio wavelengths that are suitable for the determination of time delays between image pairs. The survey is now near completion and at least 18 GL systems have been found. Here, I will discuss our efforts to measure time delays from several of these systems with...
متن کاملScaling the universe: gravitational lenses and the Hubble constant.
Gravitational lenses, besides being interesting in their own right, have been demonstrated to be suitable as "gravitational standard rulers" for the measurement of the rate of expansion of the Universe (Ho), as well as to constrain the values of the cosmological parameters such as Omegao and Lambdao that control the evolution of the volume of the Universe with cosmic time.
متن کاملThe Hubble Constant from Gravitational Lens Time Delays
There are now 10 firm time delay measurements in gravitational lenses. The physics of time delays is well understood, and the only important variable for interpreting the time delays to determine H0 is the mean surface mass density 〈κ〉 (in units of the critical density for gravitational lensing) of the lens galaxy at the radius of the lensed images. More centrally concentrated mass distribution...
متن کاملThe Hubble Constant from the Gravitational Lens
We present a refined gravitational lens model of the four-image lens system B1608+656 based on new and improved observational constraints: (i) the three independent time-delays and flux-ratios from Very Large Array (VLA) observations, (ii) the radio-image positions from Very Large Baseline Array (VLBA) observations, (iii) the shape of the deconvolved Einstein Ring from optical and infrared Hubb...
متن کاملThe Hubble Constant
Considerable progress has been made in determining the Hubble constant over the past two decades. We discuss the cosmological context and importance of an accurate measurement of the Hubble constant, and focus on six high-precision distance-determination methods: Cepheids, tip of the red giant branch, maser galaxies, surface-brightnes fluctuations, the TullyFisher relation and Type Ia supernova...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: The Astrophysical Journal
سال: 2010
ISSN: 0004-637X,1538-4357
DOI: 10.1088/0004-637x/712/2/1378