A blazing gamma-ray source

A blazing gamma-ray source
An artist's conception of a blazar, whose powerful jet of high velocity particles is generated around a supermassive black hole and aimed almost directly at Earth. Astronomers have measured and successfully modeled the very high energy gamma ray emission from a blazar using VERITAS, the Very Energetic Radiation Imaging Telescope Array System. Credit: Marscher et al., Wolfgang Steffen, Cosmovision, NRAO/AUI/NSF

Blazars are galaxies whose central, supermassive black holes are accreting material from surrounding regions. Although black hole accretion happens in many galaxies and situations, in the case of a blazar the infalling material erupts into a powerful, narrow beam of high velocity charged particles that, fortuitously, is pointed in our direction. The charged particles produce gamma ray photons, each photon packing over a hundred million times the energy of the highest energy X-ray photon seen by the Chandra X-ray Observatory. The electron beam produces many other effects, and in blazars these include rapid, strong, and incessant variability. They sometimes also include the ability to generate high-energy gamma rays.

The blazar 1ES1741+196 was first spotted in 1996 by the Einstein X-ray satellite. Followup observations determined that it is a triplet system: an elliptical galaxy with two companion galaxies close enough nearby to be an interacting triplet; a tidal tail is observed, for example, presumably the result of mutual gravitation influences. The interactions might play a role in stirring up material for . In 2011, astronomers discovered that the object also emitted , but at an intensity that made it one of the faintest such sources known.

VERITAS, the Very Energetic Radiation Imaging Telescope Array System, is an observatory designed to study gamma rays. It consists of four 12-m telescopes located at the Fred L. Whipple Observatory at Mt. Hopkins, Arizona. CfA astronomers Wystan Benbow, M. Cerruti, Pascal Fortin, V. Pelassa, and Thomas Roche were members of a team of eighty-eight astronomers who used VERITAS to study 1ES1741+196 in an effort to model this weak gamma ray blazar. They observed it successfully in several energy ranges for thirty hours over a period of several years and were able to obtain, and model, the first very high energy spectrum for the source. In general, high energy photons are produced in two processes: direct radiation from the charged particles, and scattering by the fast-moving particles of lower energy photons to much higher energies. The team successfully modeled this source including only these two, energetic processes. The result suggests that the scientists have accurately characterized this blazar - despite its faintness - as being among those that produce the most energetic gamma rays. They also found, curiously, that there is no evidence for any significant flaring in this source.


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VERITAS detects gamma rays from galaxy halfway across the visible universe

More information: "VERITAS and Multiwavelength Observations of the BL Lacertae Object 1ES 1741+196, A. U. Abeysekara et al. MNRAS 459, 2550, 2016. http://mnras.oxfordjournals.org/content/459/3/2550.abstract , DOI: 10.1093/mnras/stw664
Citation: A blazing gamma-ray source (2016, June 6) retrieved 16 September 2019 from https://phys.org/news/2016-06-blazing-gamma-ray-source.html
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Jun 06, 2016
Change the way you look at these CCM to see the mechanics, think of this object being a cosmic particle accelerator, kind of like we build on earth the environment is super hot hotter than star cores all atoms approaching the mass have their orbiting electrons stripped where there caught in gravity building a magnetic field vessel of orbiting electrons rotating around the mass, the neutron and protons continuing their journey into a super hot particle plasma kinetic collision storm orbiting the mass taking these protons and neutrons apart in high velocity kinetic collisions into their magnetic building blocks of positrons and electrons, those rain out of that storm on to that quantum particle mass ,but if to much material builds up in magnetic vessel and heats up the mass it ejects those particle out of field vessel at its poles

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