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Latest Gamma ray Stories

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2010-11-29 10:01:39

Just like archaeologists, who rely on radioactive carbon to date the organic remains from past epochs, astronomers have exploited the radioactive decay of an isotope of aluminum to estimate the age of stars in the nearby Scorpius-Centaurus association, the closest group of young and massive stars to the Sun. The new observations, performed in gamma rays by ESA's INTEGRAL observatory, provide evidence for recent ejections of matter from massive stars that took place only a few million years...

2010-11-22 07:58:00

System Would Safely Detect Ionization of Air Surrounding Containers Holding Radioactive Material COLLEGE PARK, Md., Nov. 22, 2010 /PRNewswire-USNewswire/ -- The shipment of cargo containers is a critical component of international trade and plays a fundamental role in the global economy. According to the U.S. Bureau of Customs and Border Protection, about 90 percent of the world's trade is transported in cargo containers, with almost half of incoming U.S. trade arriving by containers...

2010-11-09 20:43:05

University of Maryland researchers propose method to sniff out dirty bombs via the electromagnetic breakdown of air Researchers at the University of Maryland have proposed a scheme for detecting a concealed source of radioactive material without searching containers one by one. Detection of radioactive material concealed in shipping containers is important in the early prevention of "dirty" bomb construction. The concept, described in the Journal of Applied Physics, is based on the gamma-ray...

4e49e2822b9eb3e643ac936bc1b899741
2010-11-04 10:00:00

A table-top gamma-ray detector created at the University of Michigan can not only identify the presence of dangerous nuclear materials, but can pinpoint and show their exact location and type, unlike conventional detectors. "Other gamma ray detectors can tell you perhaps that nuclear materials are near a building, but with our detector, you can know the materials are in room A, or room B, for example," said Zhong He, an associate professor in the Department of Nuclear Engineering and...

6ed73c3134c7fc84b775c272eb9cfeae1
2010-11-04 09:15:12

Black holes could produce the enormous energies of a burst, but not neutron stars A gamma-ray burst is an immensely powerful blast of high-energy light thought to be generated by a collapsing star in a distant galaxy, but what this collapse leaves behind has been a matter of debate. A new analysis of four extremely bright bursts observed by NASA's Fermi satellite suggests that the remnant from a long-duration gamma-ray burst is most likely a black hole "“ not a rapidly spinning, highly...

2010-08-12 08:01:37

A newly developed image analysis technique has significantly improved the sensitivity limits reached by the IBIS imager on board INTEGRAL, resulting in the deepest survey ever compiled of the entire sky in the energy range between 17 and 60 keV. Pushing the instrument towards its very limits, the novel method discloses a vast number of previously undetected faint sources, galactic and extragalactic alike. For more than seven years, the INTEGRAL observatory has been surveying the entire X-ray...

519d7e5ee817fa0a06610d7b9da255df
2010-04-01 15:40:00

If our eyes could see radio waves, the nearby galaxy Centaurus A (Cen A) would be one of the biggest and brightest objects in the sky, nearly 20 times the apparent size of a full moon. What we can't see when looking at the galaxy in visible light is that it lies nestled between a pair of giant radio-emitting gas plumes ejected by its supersized black hole. Each plume is nearly a million light-years long. NASA's Fermi Gamma-Ray Space Telescope maps gamma rays, radiation that typically packs...

af9737f03c0c7b658a584e2d4d8d475a
2010-03-03 08:31:59

One of the pleasures of perusing ancient maps is locating regions so poorly explored that mapmakers warned of dragons and sea monsters. Now, astronomers using NASA's Fermi Gamma-ray Space Telescope find themselves in the same situation as cartographers of old. A new study of the ever-present fog of gamma rays from sources outside our galaxy shows that less than a third of the emission arises from what astronomers once considered the most likely suspects -- black-hole-powered jets from active...

8c9f5da9180f9cbbe904cf3711a1780c1
2010-02-18 07:56:55

Jets of particles streaming from black holes in far-away galaxies operate differently than previously thought, according to a study published today in Nature. The new study reveals that most of the jet's light"”gamma rays, the universe's most energetic form of light"”is created much farther from the black hole than expected and suggests a more complex shape for the jet. The research was led by scientists at the Kavli Institute for Particle Astrophysics and Cosmology, jointly...

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2010-02-17 07:06:12

New images from NASA's Fermi Gamma-ray Space Telescope show where supernova remnants emit radiation a billion times more energetic than visible light. The images bring astronomers a step closer to understanding the source of some of the universe's most energetic particles -- cosmic rays. Cosmic rays consist mainly of protons that move through space at nearly the speed of light. In their journey across the galaxy, the particles are deflected by magnetic fields. This scrambles their paths and...


Latest Gamma ray Reference Libraries

7_7ab115b117284658644e345b89f5ba712
2004-10-19 04:45:43

Gamma-Ray Astronomy -- Gamma-ray astronomy is the astronomical study of gamma rays. Long before experiments could detect gamma rays emitted by cosmic sources, scientists had known that the universe should be producing these photons. Work by Feenberg and Primakoff in 1948, Hayakawa and Hutchinson in 1952, and, especially, Morrison in 1958 had led scientists to believe that a number of different processes which were occurring in the universe would result in gamma-ray emission. These...

6_f3739d4b04b11a1c267bfcc286610ef92
2004-10-19 04:45:41

Hypernova -- A hypernova is a theoretical type of supernova produced when exceptionally large stars collapse at the end of their lifespan. In a hypernova, the core of the star collapses directly into a black hole and two extremely energetic jets of plasma are emitted from its rotational poles at nearly light speed. These jets emit intense gamma rays, and are a candidate explanation for gamma ray bursts. Theorists have come up with several plausible explanations for hypernovae. It may...

6_c9b95f985acbe749f13bf6301a3180a85
2004-10-19 04:45:41

Electromagnetic Spectrum -- The electromagnetic spectrum describes the various types of electromagnetic radiation based on their wavelengths. Radio, representing wavelengths from a few feet to well over a mile, is at one end of the spectrum. Gamma ray radiation is at the other end: the wavelength of the harder types is so short, in the subatomic range, that we do not have instruments capable of directly measuring it. While the above classification scheme is generally accurate, in...

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Word of the Day
malpais
  • The ragged surface of a lava-flow.
'Malpais' translates from Spanish as 'bad land.'