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Antimatter Gamma Ray Bursts

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LutzH

Fri Dec 04 2009, 02:56AM

Registered Member #1721 Joined: Sat Sept 27 2008, 08:44PM
Location:
Posts: 136

Hello:

As crazy as it sounds a laser powerfull enough for a wakefield accellerator is possible for an amature to build. First forget solid state lasers, you will never get a pulse compression Ti Sapphire laser / amplifier going unless you are very wealthy, and you have a clean room with a stone table.

Instead focus on a pulse linear electron beam pumped TEA atmospheric pressure CO2 laser. You will need a basic high vacuum system for the linear pulse electron beam pump, ebay can handle this. Then you will need to build a 200-300KV cpacitor bank with low inductance capacitors. Deionized water caps are great for this. No problem so far, you will need a clear polycarbonate rectangular box with a thin metalic electron window strip on one side, and mirrors at the ends. Fill it with CO2 and He gas at STP. All achievable things for most determined folks.

You now have a laser powerful enough for a wakefield design, especialy if you add an amplifier stage which is more of the same as above. This is the easy part, now you will have to control the beam, a mirror system is better than lenses if possible. The output window of the laser has to be Zink Selenide unless you live in Arizona and you can grow very big salt crystals :)

The only thing left now is to build the small accelerator section, here is where the gremlins and trolls live. Figure this one out and you have it :)

Good Luck!!! I hope to have started here the race to the first amature wakefield accellerator. I will even kick in a few bucks for the prize, maybe call Paul Allen :)

GhostlyFigures

Wed Mar 03 2010, 03:19PM

Registered Member #2385 Joined: Thu Sept 24 2009, 01:26AM
Location: Waxhaw, North Carolina (Or Charlotte near UNCC)
Posts: 26

Or you could just imagine in your head that you can some how blow up a star - Then you'll get quite the gamma ray burst :)

Proud Mary

Sun Mar 07 2010, 11:56AM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

Why look further than this?

A study of X-ray emission from laboratory sparks in air at atmospheric pressure

Dwyer et al 2008

We present a detailed investigation of X-ray emission from long laboratory sparks in air at atmospheric pressure. We studied 231 sparks of both polarities using a 1-MV Marx generator with gap lengths ranging from 10 to 140 cm. The X rays generated by the discharges were measured using five NaI/PMT detectors plus one plastic scintillator/PMT detector, all enclosed in 0.32-cm-thick aluminum boxes. X-ray emission was observed to accompany about 70% of negative polarity sparks and about 10% of positive polarity sparks. For the negative sparks, X-ray emission was observed to occur at two distinct times during the discharge: (1) near the peak voltage, specifically, about 1 Î¼s before the voltage across the gap collapsed, and (2) near the time of the peak current through the gap, during the gap voltage collapse. Using collimators we determined that the former emission emanated from the gap, while the latter appeared to originate from above the gap in the space over the high-voltage components. During individual sparks, the total energy of the X rays that was deposited in a single detector sometimes exceeded 50 MeV, and the maximum energy of individual photons in some cases exceeded 300 keV. X-ray emission near the peak voltage was observed for a wide range of electrode geometries, including 12-cm-diameter spherical electrodes, a result suggesting that the X-ray emission was the result of processes occurring within the air gap and not just due to high electric fields at the electrode.

Received 23 April 2008; accepted 25 September 2008; published 9 December 2008.

Citation: Dwyer, J. R., Z. Saleh, H. K. Rassoul, D. Concha, M. Rahman, V. Cooray, J. Jerauld, M. A. Uman, and V. A. Rakov (2008), A study of X-ray emission from laboratory sparks in air at atmospheric pressure, J. Geophys. Res., 113, D23207, doi:10.1029/2008JD010315.

Conundrum

Sun Mar 07 2010, 01:32PM

Registered Member #96 Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4059

interesting...

This suggests that X-rays could be generated using a Marx generator with no vacuum tube needed.

i had a conversation with someone a while back over here concerning thunderstorms, and mentioned the gamma ray discovery... he hadn't heard of it.

if this is indeed the case then the nitrogen cycle could be driven in part by cosmic ray flux (the lack of which would reduce the number and intensity of lightning strikes)...

food for thought.

-A

Proud Mary

Sun Mar 07 2010, 02:14PM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

Conundrum wrote ...

interesting...

This suggests that X-rays could be generated using a Marx generator with no vacuum tube needed.

A number of papers have appeared over the last decade demonstrating X-ray production in systems at atmospheric pressure, some simple, some not.

Volume x-ray emission in gas diodes at atmospheric pressure

I. D. Kostyrya1, V. F. Tarasenko1 Contact Information, A. N. Tkachev2 and S. I. Yakovlenko2 Contact Information
(1) Institute of High-Current Electronics, Siberian Division, Russian Academy of Sciences, Tomsk, Russia
(2) Institute of General Physics, Russian Academy of Sciences, Moscow, Russia

Abstract The generation of x-rays and high-energy electron beams in gas diodes filled with air and nitrogen at atmospheric pressure has been studied by experimental and theoretical methods. It is established that soft x-ray radiation is not only generated in the region of dense discharge, but is predominantly emitted from a weak-current discharge region. For a high-energy electron beam formation in the gap, the role of the voltage pulse front is not less important than that of the voltage amplitude; the electric field strength at the cathode has an optimum value for the electron beam formation.

PACS numbers 52.80.Tn
Original Russian Text

X-ray radiation from the volume discharge in atmospheric-pressure air

V. B. Bratchikov1, K. A. Gagarinov1, I. D. Kostyrya2, V. F. Tarasenko2 Contact Information, A. N. Tkachev3 and S. I. Yakovlenko3
(1) Zababakhin All-Russia Institute of Technical Physics, Russian Federal Nuclear Center, Snezhinsk, Chelyabinsk oblast, 456770, Russia
(2) Institute of High-Current Electronics, Siberian Division, Russian Academy of Sciences, AkademicheskiÄ pr. 2/3, Tomsk, 634055, Russia
(3) Prokhorov General Physics Institute, Russian Academy of Sciences, ul. Vavilova 38, Moscow, 119991, Russia

Abstract: X-ray radiation from the volume discharge in atmospheric-pressure air is studied under the conditions when the voltage pulse rise time varies from 0.5 to 100 ns and the open-circuit voltage amplitude of the generator varies from 20 to 750 kV. It is shown that a volume discharge from a needle-like cathode forms at a relatively wide voltage pulse (to â‰ˆ60 ns in this work). The volume character of the discharge is due to preionization by fast electrons, which arise when the electric field concentrates at the cathode and in the discharge gap. As the voltage pulse rise time grows, X-ray radiation comes largely from the discharge gap in accordance with previous experiments. Propagation of fast avalanche electrons in nitrogen subjected to a nonuniform unsteady electric field is simulated. It is demonstrated that the amount of hard X-ray photons grows not only with increasing voltage amplitude but also with shortening pulse rise time.

PACS numbers 52.80.Yr
Original Russian Text Â© V.B. Bratchikov, K.A. Gagarinov, I.D. Kostyrya, V.F. Tarasenko, A.N. Tkachev, S.I. Yakovlenko, 2007, published in Zhurnal TekhnicheskoÄ Fiziki, 2007, Vol. 77, No. 7, pp. 34â€“42.

From my very limited experience, the chief difficulty facing the amateur scientist with experiments like these is the detection and measurement of X-rays below 5keV, where most of the action takes place, and designing and constructing signal detection and processing gear with excellent SNR.

Conundrum

Mon Mar 08 2010, 08:18AM

Registered Member #96 Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4059

hmm... wonder if something like a multichannel plate (electron multiplier) would work? now i've managed to locate some homemade conducting adhesive this could work...

-A

Proud Mary

Mon Mar 08 2010, 04:05PM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

Conundrum wrote ...

hmm... wonder if something like a multichannel plate (electron multiplier) would work? now i've managed to locate some homemade conducting adhesive this could work...

-A

PIN photodiodes like BPX61 have high quantum efficiency below 5keV, and even more at 1keV, if once you remove the lens, which is opaque to very soft X-rays. Using them as single photon detectors requires an ultra high Z low noise charge amplifier type input. The charge amplifier provides information about the energy of the photons, which can be resolved into channels, when it becomes an X-ray spectrometer. You can start off with a PN4117A FET as the first amplifier, and then move on to specialised electrometer chips like the "Ultra Ultra-Low Input Current Amplifier" LMC6001 when you're ready.

You can download the paper below for free from Science Direct, and it might give you a bit of inspiration.

Luiz A.P. Santosa,âˆ—, Cinthia M.S. MagalhÃ£esa,b, Jonas O. Silvaa,b, JoÃ£o A. Filhob,c,
Eronides F. Silva Jr.d, Walter M. Santose
Afeasibility study of a phototransistor for the dosimetry of computerized
tomography and stereotactic radiosurgery beams
Radiation Measurements 43 (2008) 904 â€“ 907

I reckon it good practice to have two completely different types of detector running for very soft X-rays - say, an Si detector as above, and a proportional counter
such as butane, or butane-argon with a Kapton or aluminized mylar window - or maybe even a funky gold leaf X-ray bolometer if you want to measure X-ray fluence all the way down to 10eV.

Conundrum

Thu Mar 11 2010, 07:22PM

Registered Member #96 Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4059

hmm... aluminised mylar?
isn't that the same as the stuff used for helium party balloons?

also how similar is the "foil" found in grey antistatic bags?

On a similar note, i found that pyrolytic graphite works fairly well as a window material as it can be "split" then sanded down to minimal thickness.

-A

Proud Mary

Thu Mar 11 2010, 08:09PM

Registered Member #543 Joined: Tue Feb 20 2007, 04:26PM
Location: UK
Posts: 4992

Conundrum wrote ...

hmm... aluminised mylar?

Ebay uk; "Emergency Space Foil Blanket"

Butane proportional counter tubes can be operated at atmospheric pressure, so the window has no pressure upon it. (3.25 kV, 9ct gold anode wire, anhydrous conditions)

Conundrum

Fri Mar 17 2017, 02:48PM

Registered Member #96 Joined: Thu Feb 09 2006, 05:37PM
Location: CI, Earth
Posts: 4059

The really interesting thing is that it has 2 upvotes.
I am not entirely sure but my analysis (flawed though it might be) could be somewhat useful.

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