AAS presentation on latest GL findings.
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At the forthcoming AAS conference - on Monday (6/1/14) there will be a presentation on some latest GL findings
http://www.nasa.gov/content/2014-nasa-aas-events/
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Budgieye
moderator
Interesting
TOPIC: Astronomers using NASA's Fermi observatory have made the first gamma-ray measurements of a gravitational lens, a kind of natural telescope formed when a rare cosmic alignment allows the gravity of a massive object to bend and amplify light from a more distant source. The accomplishment opens new avenues for research, including a novel way to probe emission regions near supermassive black holes. It may even be possible to uncover new gravitational lenses with data from the Fermi Gamma-ray Space Telescope.
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JeanTate
in response to Budgieye's comment.
In today's astro-ph preprints: "Fermi-LAT Detection of Gravitational Lens Delayed Gamma-ray Flares from Blazar B0218+357" (1401.0548):
Using data from the Fermi Large Area Telescope (LAT), we report the first clear gamma-ray measurement of a delay between flares from the gravitationally lensed images of a blazar. The delay was detected in B0218+357, a known double-image lensed system, during a period of enhanced gamma-ray activity with peak fluxes consistently observed to reach >20-50 times its previous average flux. An auto-correlation function analysis identified a delay in the gamma-ray data of 11.46 +/- 0.16 days (1 sigma) that is ~1 day greater than previous radio measurements. Considering that it is beyond the capabilities of the LAT to spatially resolve the two images, we nevertheless decomposed individual sequences of superposing gamma-ray flares/delayed emissions. In three such ~8-10 day-long sequences within a ~4-month span, considering confusion due to overlapping flaring emission and flux measurement uncertainties, we found flux ratios consistent with ~1, thus systematically smaller than those from radio observations. During the first, best-defined flare, the delayed emission was detailed with a Fermi pointing, and we observed flux doubling timescales of ~3-6 hrs implying as well extremely compact gamma-ray emitting regions.
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