Conveners
12 - Gravitational lensing
- Ludovic Van Waerbeke (University of British Columbia)
12 - Gravitational lensing
- Ludovic Van Waerbeke (University of British Columbia)
Hiromi Saida
(Daido University)
12/17/15, 2:00 PM
Talk
According to the general relativity (GR), the black hole (BH) is characterized by three parameters: mass $M$, spin angular momentum $J$ and electric charge $Q$.
In real cases, the charge is expected to be zero, $Q=0$.
Then, the "BH observation" may be understood as the measurement of $M$ and $J$ through a direct observation of GR phenomena, for example the strong gravitational lens effect....
R. Benton Metcalf
(Univerity of Bologna)
12/17/15, 2:21 PM
Talk
The Euclid mission is expected to discover perhaps two orders of magnitude
more strong gravitational lenses than are known today. These will be quasar-galaxy,
galaxy-galaxy and galaxy-cluster lenses. I will discuss what is required to find and
process such a large number of lenses. I will then describe what can be learned from
these lenses with respect to the dark matter...
Dr
Zuzanna Kostrzewa-Rutkowska
12/17/15, 2:42 PM
Talk
We present the results of our search for gravitationally lensed quasars in the OGLE survey. We show candidates from a 650 square degrees area behind the Magellanic Clouds System. The study of strong lensing time delays serves as a powerful probe in cosmology. The OGLE database provides long time light curves, allowing for a cost-effective way to accurately derive time delays and therefore...
Dr
Huanyuan Shan
(EPFL)
12/17/15, 3:03 PM
Talk
We present the largest weak lensing mass map covering ~3000 square degrees of
the DECaLS DR1 Survey. A good agreement can be found between optical and dark matter maps. Comparing with the mass maps from CFHT Stripe 82 Survey (CS82), the similar high signal-to-noise ratio peaks can be found, which means the systematics of the maps are well controlled. We found ~50,000 WL peaks with SNR higher...
Mr
Yuuki Omori
(McGill University)
12/17/15, 3:24 PM
Talk
Large scale structure in the universe causes gravitational lensing of
the cosmic microwave background (CMB), which has now been
well-measured by several CMB experiments. By cross-correlating CMB
lensing with tracers of large scale structure (like galaxies), it is
possible to obtain new constraints on cosmology and a better
understanding of possible systematic errors in cosmological...
Dr
Dominique Eckert
(University of Geneva)
12/17/15, 4:15 PM
Talk
In the local Universe, about half of the total baryon content of the Universe is still escaping our census. Understanding the state and distribution of these missing baryons is a major question for our knowledge of galaxy evolution and cosmology. Numerical simulations predict that the missing baryons should be in the form of a very diffuse, warm-hot (T~1e5-1e7 K) state, which would remain...
Vitalii Sliusar
(Astronomical Observatory of Taras Shevchenko National University of Kyiv, Ukraine)
12/17/15, 4:55 PM
Talk
We study effects due to a possible presence of putative dark matter mini-halos (DM clumps) in the light curves of source images of the extragalactic gravitational lens systems. The extended clumps are described by means of a simplified model of the lens mapping. Every microlens consists of a central point mass surrounded by a concentric extended mini-halo; this is characterized by the ratio q...
Mr
Markus Rexroth
(EPFL - EPF Lausanne)
12/17/15, 5:35 PM
Poster
Flexion is the second order weak gravitational lensing effect which is responsible for the arclike appearance of lensed sources. Its strong signal in the intermediate regime and the orthogonality to the weak lensing shear field make flexion an ideal complement to today's gravitational lensing measurements. Furthermore, its high sensitivity to local density peaks makes it a great tool for...
Mr
Shohei Saga
(Naogya university)
12/17/15, 5:38 PM
Poster
Vector mode of cosmological perturbation theory imprints characteristic signals on the weak lensing signals such as curl- and B-modes which are never imprinted by the scalar mode.
However, the vector mode is neglected in the standard first-order cosmological perturbation theory since it only has a decaying mode.
This situation changes if the cosmological perturbation theory is expanded up to...
Dr
Zuzanna Kostrzewa-Rutkowska
(Warsaw University Astronomical Observatory)
12/17/15, 5:41 PM
Poster
Most stellar remnants so far have been found in binary systems where they interact with matter from their companion. Isolated neutron stars and black holes are hard to find as they do not emit light, yet they are predicted to be present in our Galaxy in vast numbers.
We explored the OGLE-III database of 150 million objects observed in years 2001-2009 and found 59 microlensing events...
