Lightning and Terrestrial Gamma-Ray Flashes (TGFs)

[MGmirkin]

(Terrestrial gamma-ray flashes)
http://sprg.ssl.berkeley.edu/%7Etohban/ ... icle_id=32

It seems that lightning and Terrestrial Gamma-ray Flashes are closely related in timing and proximity.

Terrestrial gamma-ray flashes (TGFs) are very brief bursts of gamma radiation (typically around 1 millisecond long) coming upwards from the Earth's atmosphere from somewhere in the vicinity of a thunderstorm.

[...]

Sprites and TGFs were guessed, for several good reasons, to be related. Theorists refined an idea called relativistic runaway breakdown to explain where the gamma-rays come from. In this process, one or more high-energy "seed" electrons (provided, perhaps, by a cosmic ray) are accelerated by a strong electric field and knock further electrons off other atoms, which are thus "born" with high energy, too. These electrons create bremsstrahlung radiation when they interact with nuclei in the atmosphere just as solar-flare electrons do at the Sun.

[...]



[...]

We learned two things right away from these first events: that TGFs are much more common than previously thought, and that they extend up to gamma-ray energies as high as 30 MeV, with just the spectral shape predicted by the relativistic runaway model.

[...]

Sideshow or opening act?

Since then, several collaborations have been comparing the global map of RHESSI TGFs to maps of lightning (Figure 2), studying the average TGF spectrum in detail (Figure 3), and comparing individual TGFs with radio signals from the associated lightning. All of these lines of study seem to be pointing to a common conclusion: that TGFs are not associated primarily with the exotic sprites, elves, and blue jets, which occur at very high altitudes, but with lightning itself. The TGFs we see may be the tip of the iceberg, and many more probably await, buried from our view by overlying atmosphere. They may even turn out to be the still-unknown trigger mechanism for lightning.

Cheers,
~Michael Gmirkin

[StefanR]

Very nice to put it there, a while ago I posted some in the sublime "New info on Sprites"-thread:
Terrestial Gamma-ray Flash

and

Ion structures in Inner Magnetosphere .ppt

and maybe this could add some insight:

Cell Dynamical System Model for Thundercloud Electrification

and maybe also

The Inner Magnetosphere

[MGmirkin]

Very nice to put it there, a while ago I posted some in the sublime "New info on Sprites"-thread:

Ahh, must've missed it... A rather interesting result.

~Michael Gmirkin

[webolife]

A couple thoughts/questions on TGFs and Lightning:
1. Are TGFs associated with positive or negative lightning?
2. GRBs from outer space affect our atmosphere apparently... any association between TGFs and GRBs?
3. I see GRB's generally associated with "pinch" effects at the galactic/stellar scale. Before coming to EU I thought these were some type atomic/molecular scale "decay" phenomenon, related to gravitational compression shock, but now I see the Z and theta pinch phenomena as viable options. In a lightning strike, is the beadiness of lightning related to "pinching", and could that be causing the TGFs?
4. Are TGFs and Lightning flashes two views of the same phenomenon?

[MGmirkin]

A couple thoughts/questions on TGFs and Lightning:
1. Are TGFs associated with positive or negative lightning?
2. GRBs from outer space affect our atmosphere apparently... any association between TGFs and GRBs?
3. I see GRB's generally associated with "pinch" effects at the galactic/stellar scale. Before coming to EU I thought these were some type atomic/molecular scale "decay" phenomenon, related to gravitational compression shock, but now I see the Z and theta pinch phenomena as viable options. In a lightning strike, is the beadiness of lightning related to "pinching", and could that be causing the TGFs?
4. Are TGFs and Lightning flashes two views of the same phenomenon?

Well, for one, I think they're still in the process of designing several new missions / instruments to study at least a few of these questions. Neg/pos lightning might be ferreted out (don't know if they're looking at that specifically)? Don't recall if they said they'd be looking at GRBs. Though I seem to recall one or two unrelated articles had intimated that GRBs may play a role in cloud formation and/or other atmospheric processes. So, it would certainly be interesting to see if there were any interesting correlations to be found.

I think there are two theories of the "string of pearls" or "sausage" formation of lightning:

1) Lightning channels twist and kink, where the channel travels in the same direction as the line of sight, it appears to be brighter. Where it travels perpendicular to the line of sight it appear dimmer, this giving the mistaken impression of bright sections interspersed with dim sections.
2) It's an actual plasma effect or sausage instability, wherein the channel pinches off into discrete sections as it completes, thus there are in fact periodic breaks in the channel which exit arc / glow mode prior to the stuff between the pinched points.

It's not always clear whether one or the other is responsible for the look inf beaded lightning. Don't know if it's ever been fully resolved?

~Michael Gmirkin

[StefanR]

http://www.thunderbolts.info/forum/phpBB3/viewtopic.php?p=7560#p7560

Gamma ray flashes due to plasma processes in the atmosphere: Role of whistler waves

Abstract

A proposed mechanism for the generation of gamma ray flashes in the atmosphere, observed on Compton Gamma Ray Observatory satellite, is a runaway discharge mediated by whistler waves. In this model the relativistic electrons produced by a cosmic ray shower during a thunderstorm lead to a runaway discharge, which is maintained by the interaction with whistler waves and the relativistic electrons propagate up in ducts produced by the self-focusing of these waves. The paper presents a detailed study of the instability which develops in the lower stratosphere when a beam of hot magnetized electrons interacts with whistler waves. It was shown that the growth rate of such instability depends on the number density of hot electrons and on their collision rate, and it peaks at about 25 km. The instability develops under the conditions for runaway breakdown, similar to those leading to the generation of strong narrow bipolar pulses, which indicates a possible correlation between these two phenomena.

V. CONCLUSION
In this paper we have discussed a novel scenario for the
creation of gamma ray flashes. During a typical lightning
discharge, a small fraction of the energy of the 500 kJ of
EMP generated can sustain a population of 1016 energetic
electrons ~;1 MeV!, which can be transported in selffocused
whistler wave ducts to a height of about 30 km. At
this height these energetic electrons can give rise to the 1 ms
gamma ray flash by the process of bremsstrahlung and those
flashes can escape from the atmosphere into space. It is only
through this whistler-medicated, self-focusing instability that
the energetic electrons can be delivered to the desired
heights. The characteristic time scale of the gamma ray flash
is also of the order of the time scale for the lightning flash.
The observations of whistlers during lightning flashes is well
documented.19 Thus the proposed mechanism brings together
a series of naturally occurring events to provide a viable
transport mechanism for the energetic electrons to the 30–35
km height for conversion into gamma rays.

[StefanR]

January 29, 2010: High-energy bursts of gamma rays typically occur far out in space, perhaps near black holes or other high-energy cosmic phenomena. So imagine scientists' surprise in the mid-1990s when they found these powerful gamma ray flashes happening right here on Earth, in the skies overhead.
They're called Terrestrial Gamma-ray Flashes, or TGFs, and very little is known about them. They seem to have a connection with lightning, but TGFs themselves are something entirely different.

To investigate, Rowland and his colleagues at GSFC, Siena College, Universities Space Research Association, and the Hawk Institute for Space Sciences are planning to launch a tiny, football-sized satellite called Firefly in 2010 or 2011. Because of its small size, Firefly will cost less than $1 million — about 100 times cheaper than what satellite missions normally cost. Part of the cost savings comes from launching Firefly under the National Science Foundation's CubeSat program, which launches small satellites as "stowaways" aboard rockets carrying larger satellites into space, rather than requiring dedicated rocket launches.

http://science.nasa.gov/headlines/y2010/29jan_firefly.htm?list14818

[seasmith]

TGF’s Terrestrial Gamma-ray Flashes


Electromagnetic Spectrum




http://hyperphysics.phy-astr.gsu.edu/hbase/ems1.html#c1

“The electromagnetic spectrum covers a wide range of wavelengths and photon energies.

So the spherical multi-layered Earth receives massive, relatively medium wavelength, low energy radiation from the sun and then rebroadcasts across the spectrum: “whistlers”, lightning “flashes”, and on up to extremely high frequency gamma “rays”.

What’s going on at wave lengths shorter than gamma ?
Why can’t we detect the “photons” after that ? Have they gone linear, or around the bend to complete the EM/ES aetheric circuit ?

~

[RayTomes]

...
What’s going on at wave lengths shorter than gamma ?
Why can’t we detect the “photons” after that ? Have they gone linear, or around the bend to complete the EM/ES aetheric circuit ?

You have matter!

When you get to 10^20 Hz, that is the (Compton) frequency of an electron
At 10^23 Hz you have the (Compton) frequency of nucleons
Cosmic rays do have energies way beyond that.

[RayTomes]

(Terrestrial gamma-ray flashes)
http://sprg.ssl.berkeley.edu/%7Etohban/ ... icle_id=32

It seems that lightning and Terrestrial Gamma-ray Flashes are closely related in timing and proximity.

Terrestrial gamma-ray flashes (TGFs) are very brief bursts of gamma radiation (typically around 1 millisecond long) coming upwards from the Earth's atmosphere from somewhere in the vicinity of a thunderstorm.
...

Hi Michael

This is wonderful stuff. First I heard of these.

I was aware that lightning was way more prevalent at certain places around the earth. These being the same, I think there is a way to look at it that makes some sense. First notices that the three places are fairly evenly spread, making a 4th harmonic of the Earth circumference (the 4th location is in the Pacific over sea and only shows up weakly).

The Schumann resonance frequency is ~7.6 Hz, and harmonics of this are generally observed especially up to about 6th order. The 4th harmonic is around 26 Hz I think

If you think about what happens when there is a big electrical discharge from a bolt of lightning, a circular wave goes out around the world and converges on the exact opposite point after about 66 ms. That energy then expands from that point and reconverges at the original location another 66 ms later. This sets of the next lightning bold zap. So lightning shows these clear zap-zap-zap effects at the Schumann resonance.

Now I liken this to the effects found in sonoluminescence or even in sonofusion (see http://en.wikipedia.org/wiki/Bubble_fusion) where energy is concentrated to a point. Because the inverse square law is operating in reverse, you get this huge concentration of energy at a point. Zap!

I first discovered this effect for myself when studying standing waves in a cup of tea. When I jiggled the cup just right the waves converged with every increasing amplitude and sent a jet of hot tea into my eye! After that I used my computer sound speakers and cold water to study this stuff.

[junglelord]

Tesla knew more about the earth and lightnting then modern men and we are just starting to catch up, after 100 years of misdirection.

[seasmith]

Ray Tomes wrote:

seasmith wrote:
...
What’s going on at wave lengths shorter than gamma ?
Why can’t we detect the “photons” after that ? Have they gone linear, or around the bend to complete the EM/ES aetheric circuit ?

You have matter!

Exactly !

s

[solrey]

It's as simple as pinch instabilities along the discharge filament. Plasma pinches are well known for producing radiation across the entire EM spectrum, including gamma rays.

Pinch

Pinches are created in the laboratory in equipment related to nuclear fusion, such as the Z-pinch machine and high-energy physics, such as the dense plasma focus. Pinches may also become unstable, and generate radiation across the electromagnetic spectrum, including radio waves, x-rays and gamma rays, and also neutrons and synchrotron radiation. Types of pinches, that may differ in geometry and operating forces, include the Cylindrical pinch, Inverse pinch, Orthogonal pinch effect, Reversed field pinch, Sheet pinch, Screw pinch (also called stabalized z-pinch, or θ-z pinch), Theta pinch (or thetatron), Toroidal pinch, Ware pinch and Z-pinch.

Neutron and high energy deuteron anisotropy investigations in plasma focus device

The anisotropies of neutron and high energy deuteron emissions from the NX2 plasma focus device [M. V. Roshan et al., Phys. Lett. A 373, 851 (2009)] are studied. The nuclear activation of graphite targets is used to measure the fluences of high energy deuterons in the axial and radial directions. Two bismuth germanate scintillation detectors connected to multichannel analyzer systems are used for the detection of 511 keV gamma rays resulting from positron annihilation in the two targets.

Neutron generation in lightning bolts

In our experiment, we have attempted to keep the cosmic-ray neutron background at a negligible level by searching for neutrons from individual lightning strokes, for a time-interval comparable with the duration of the lightning stroke. Here we present the first experimental evidence that neutrons are generated in lightning discharges, with 107−1010 neutrons per stroke. Whether these neutrons are thermonuclear in origin, or are generated by non-thermal processes, remains to be determined.

[mharratsc]

Hey, check this out- compare the locations of the TGF's with the diocotron instabilities (at least thats what I think they are) in the plasma filaments below:




and from the recent TPOD 'Plasma In Three Dimensions (http://www.thunderbolts.info/tpod/2010/arch10/100120dimensions.htm):




Does it seem as though there is a locational correlation to anyone else, or is it just me? o.O

If we can map those Uv 'hotspots' and they are associated with extremes in electrical discharging between Earth and atmosphere, and one would presume that there were some form of electrical storm associated with them as well- would that help with meteorological 'Early Warning' systems, do you think?

[junglelord]

Yeah, thats a match to my eyes.
Great thinking.