Questions tagged [gamma-rays]
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Who - if anyone - predicted the emission of gamma rays from jetted active galaxies? An historiographical inquiry
We know that the relativistic electrons that produce synchrotron radiation in the jets of active galaxies also produce gamma radiation via the inverse Compton mechanism (in the most simple scenario ...
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Why is it Cosmic microwave background not Cosmic gamma ray background [duplicate]
If the universe was at so much heat at the singularity point at big bang , Then the light of CMB must be gamma rays (high energy photons) but how did they transfer into microwaves?
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"First gamma-ray eclipses from ‘spider’ star systems" - but have other types of gamma-ray eclipses been observed?
The January 28, 2023 NASA News item NASA’s Fermi Detects First Gamma-Ray Eclipses From ‘Spider’ Star Systems begins:
Scientists have discovered the first gamma-ray eclipses from a special type of ...
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Could the newly discovered glow in the solar system be antimatter?
Could the newly discovered glow in the solar system be a sparse cloud of interstellar antimatter slowly annihilating with the solar wind?
The glow I am talking about is discussed at: https://www.nasa....
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Where can I find definitions of minimum detectable flux sensitivity and signal to noise ratio?
I am struggling to find references that give precise definitions to these concepts. Even in PhD theses on the subject of gamma-ray astrophysics, for example, students do not define it precisely or ...
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Gamma Ray Spectroscopy in detecting hydrogen
My professor explained saying that bombarding the surface with cosmic rays breaks off a few neutrons from nuclei and the nucleus, having undergone a change in energy level, emits a gamma photon. The ...
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Do gamma rays escape from stars when turning into white dwarfs
I'm very curious about this : if the Sun were to become a white dwarf, would Earth get blasted with high-energy electromagnetic radiation? I know that current predictions say that Earth will be ...
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Are plasma nuclei detectable? By the occasional emission of gamma rays, perhaps?
As stated above....
How often do nuclei stripped bare emit radiation?
Can nuclei be identified by the wavelengths or amplitudes of gamma rays they emit? How about isotopes?
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Why is the number of Long Gamma Ray Burst (LGRB) event occurrences greater than the number of Short Gamma Ray Burst (SGRB) event occurrences?
I collected from NASA this histogram plotting the number of GRBs vs the duration of GRBs.
Now my question is, why is the number of Long Gamma Ray Bursts (LGRBs) events occurrences greater than the ...
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Why can there be several seconds of lag between a binary neutron star merger and the emission of gamma rays from the same area?
Answers to: Gravitational waves and gamma ray burst: how were the error bars determined for this speed of gravity calculation? Was $H_0$ used? go into substantial detail explaining this determination. ...
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How does the field decay of a magnetar power the emission of high-energy electromagnetic radiation?
In Space.com's Dr. Pulsar and Mr. Magnetar? 2 Star Types May Turn into Each Other (and in the linked video) "Tom Prince, a physics professor at the California Institute of Technology and a senior ...
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What are realistic and unrealistic values for the high energy gamma ray spectral indices of pulsar wind nebulae?
This summer, I was working on a project fitting very high energy gamma ray spectra of the Crab Nebula, a pulsar wind nebula. At energies about $\sim$1 TeV, a simple power law suffices, i.e. $\phi(E)\...
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Fermi-LAT gamma ray spectrum too high [closed]
I am extracting gamma ray spectrum from Fermi-LAT data. My spectrum is a lot higher than the ones on previous studies of the same object. What could cause a spectrum to go too high?
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Can Fermi Bubbles be produced in non-spiral galaxies?
In 2010 observations with the Fermi Gamma-ray Space Telescope discovered giant bubbles which have been named Fermi Bubbles. Similar structures have also been discovered by Pshirkov et al. (2016) ...
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Is there evidence of super-heavy elements in the x-ray and gamma-ray spectrums of neutron stars?
It occurs to me, that between the surface and interior of neutron stars, gravitational pressure might produce super-heavy elements and that signatures of such elements might be detectable in the star'...
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What experiment does this "Tracing the History of Starlight" video try to explain?
The YouTube video Tracing the History of Starlight with NASA's Fermi Mission describes observation by the Fermi gamma ray telescope of EBL (extragalactic background light) gamma rays from 2,000 ...
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