Antimatter Gamma Ray Bursts
cduma, Wed Nov 25 2009, 12:19AM
After reading this article I began to wonder if my 28KJ Capacitor bank may be able to reproduce the above^. I would very much like to have a small jar of antimatter so that I could hold the world hostage. Any ideas about how I could for one, measure gamma ray bursts?
Re: Antimatter Gamma Ray Bursts
Frosty90, Wed Nov 25 2009, 01:21AM
Do these gamma bursts originate in the upper atmosphere? Or closer to the ground? Maybe you'd have to create a discharge in a low preassure environment. I suspect that a 'home-brew' attempt to recreate it would require some fairly fancy detector equipment to sort it out from the background radiation. But it would be immensley cool to re-create this phenomenon.
Cheers
Jesse
Frosty90, Wed Nov 25 2009, 01:21AM
Do these gamma bursts originate in the upper atmosphere? Or closer to the ground? Maybe you'd have to create a discharge in a low preassure environment. I suspect that a 'home-brew' attempt to recreate it would require some fairly fancy detector equipment to sort it out from the background radiation. But it would be immensley cool to re-create this phenomenon.
Cheers
Jesse
Re: Antimatter Gamma Ray Bursts
cduma, Wed Nov 25 2009, 05:48PM
Clouds (that produce lightning) are not very high up except for the very top of that really nasty one that makes all those twisters.
Other than holding the world hostage to the tune of one Bugati it would be really neat to study gravity waves which in theory accompany large gamma ray bursts. Unfortunatly the only device capable of measuring gravity changes in real time that I know of has a rather prohibitive cost. It operates similar to how noise cancelling headphones do but, it uses lasers aimed at eachother and the beams are aligned so perfect that they cancel each other out and a gravity wave will change the distance between them just enough to cause a visible burst of light. Just imagine how difficult it would be to align two lasers EXACTLY 560nM*10^XX apart. I dont remember what frequency the lasers are so I just picked 560nM because it sounded familiar...
cduma, Wed Nov 25 2009, 05:48PM
Clouds (that produce lightning) are not very high up except for the very top of that really nasty one that makes all those twisters.
Other than holding the world hostage to the tune of one Bugati it would be really neat to study gravity waves which in theory accompany large gamma ray bursts. Unfortunatly the only device capable of measuring gravity changes in real time that I know of has a rather prohibitive cost. It operates similar to how noise cancelling headphones do but, it uses lasers aimed at eachother and the beams are aligned so perfect that they cancel each other out and a gravity wave will change the distance between them just enough to cause a visible burst of light. Just imagine how difficult it would be to align two lasers EXACTLY 560nM*10^XX apart. I dont remember what frequency the lasers are so I just picked 560nM because it sounded familiar...
Re: Antimatter Gamma Ray Bursts
cduma, Wed Nov 25 2009, 05:49PM
If anything productive arises from this thread I will be absolutely amazed. This thread is more for fanciful thinking.
cduma, Wed Nov 25 2009, 05:49PM
If anything productive arises from this thread I will be absolutely amazed. This thread is more for fanciful thinking.
Re: Antimatter Gamma Ray Bursts
MinorityCarrier, Wed Nov 25 2009, 06:33PM
I was thinking, fancifully, that there must be some potent pharmacologicals being used to fuel this thread.
MinorityCarrier, Wed Nov 25 2009, 06:33PM
I was thinking, fancifully, that there must be some potent pharmacologicals being used to fuel this thread.
Re: Antimatter Gamma Ray Bursts
cduma, Wed Nov 25 2009, 08:20PM
Yeah! I found some pills! And I ate them all! There were red ones, blue ones, all sorts of colors and they were yummy.
cduma, Wed Nov 25 2009, 08:20PM
Yeah! I found some pills! And I ate them all! There were red ones, blue ones, all sorts of colors and they were yummy.
Re: Antimatter Gamma Ray Bursts
wylie, Thu Nov 26 2009, 03:19AM
<Armchair Nuclear Physicist On>
The whole thing sounded fishy, but after a little checking, apparently it's widely accepted that lightning produces actual gamma rays.
Ok, so we have the signature of e-/e+ annihilation from lightning....but where are the positrons coming from in the first place? I was under the impression that all the EM output from lightning was from electron excitement/relaxation, which would make it (very hard) x-rays, not gamma rays.
Is it possible that lightning could excite an electron far enough that when it transitions back down to the ground state, it would emit an x-ray of high enough energy/freq to allow pair production? Could the discharge possibly accelerate some electrons hard enough to emit some synchrotron/Bremsstrahlung that enables the pair production?
In any event, as far as antimatter-in-the-lab goes, this seems like an inefficient, brute force approach. All that energy going into heat and visible light. Probably easier to just setup a LINAC and slam electrons into an appropriate target. Or fire a megafast highpower laser onto some gold. Pyroelectric crystals look pretty cool too, but information is scant so far.
I'm not very clear on the laser+gold target method. 1.022meV corresponds to 1.21pm light (for photon-nucleus pair production; 511keV = 2.42pm, for photon-photon pair production). I was assuming that, like the photoelectric effect, frequency of light was the important factor not intensity. I can't (quickly) find construction details for the Titan laser, but it looks like it's TI:Sapphire, so its not producing extremely hard x-rays. Is this some non-linear effect achievable even with visble/UV light, provided you can dump enough power in a small enough time and space? Would seem to be what they're saying with: "When a short pulse with intensity greater than 10^19 watts per square centimeter strikes a target, electrons with energies up to 3 megaelectronvolts are created."
From another article about Titan, specifically about positron creation: "As they move close to the gold nucleus, the electrons each break apart into a lower-energy electron and its anti-matter opposite, a positron. The high-energy electrons would naturally break down into matter and anti-matter pairs; the gold simply speeds up the transformation."
I'm really not sure what physical process they're talking about there, anyone have a clue? Still, seems plausible that electrons accelerated to 3meV could be involved in pair production somehow, since it only requires double the rest mass/energy of an electron (511keV*2). Could it just be the idea from above: The 3meV electron transitions to a lower state, letting out a 1.022meV x-ray which triggers the pair production?
Now, skipping ahead to when you have your petawatt laser facility completed, we need to consider storage of your positrons next. An ultra-hard vacuum, materials that won't out-gas at all, and some serious trapping fields. Actually, sounds easier than the laser ;) Then we can work on the anti-proton facility next-door, and we'll have anti-hydrogen in no time. At which point i propose we start working on fusion of anti-hydrogen for the production of heavier anti-elements. Once we get upto anti-carbon, we can construct some microscopic circuit elements and study positron current flow, which i think would be Too Cool For School.
We're only a few steps away then from harnessing the positron flow from my singularity reactor concept. (feed matter to a micro-singularity to produce jets of 1.022meV photons for pair-production, and divert the resultant charged particles to the (matter and antimatter) loads. Then let them annihilate on the other side, and use a yet-to-be-discovered way of harnessing work from compton scattering by the resulting 511keV photons. Once the photon's have scattered down to UV energies, they're directed through layers of photovoltaic nanoantennae. Talk about energy efficiency. I'm betting the artificial singularity warpcore in romulan warbirds worked along those lines ;) )
Back to reality now. To detect any possible gamma rays from a discharge, looks like the prevailing technique is still scintillators and photomultiplier tubes (or avalanche photodiodes) as in PET scanners.
I think if you could get the discharge from your 28KJ bank to mimic a lightning bolt, it would probably be worth looking for super-high-energy photons. Aren't Marx generators typically used to simulate lightning though? (Maybe a more convenient and efficient route for the search?)
</Armchair Nuclear Physicist Off>
wylie, Thu Nov 26 2009, 03:19AM
<Armchair Nuclear Physicist On>
The whole thing sounded fishy, but after a little checking, apparently it's widely accepted that lightning produces actual gamma rays.
Ok, so we have the signature of e-/e+ annihilation from lightning....but where are the positrons coming from in the first place? I was under the impression that all the EM output from lightning was from electron excitement/relaxation, which would make it (very hard) x-rays, not gamma rays.
Is it possible that lightning could excite an electron far enough that when it transitions back down to the ground state, it would emit an x-ray of high enough energy/freq to allow pair production? Could the discharge possibly accelerate some electrons hard enough to emit some synchrotron/Bremsstrahlung that enables the pair production?
In any event, as far as antimatter-in-the-lab goes, this seems like an inefficient, brute force approach. All that energy going into heat and visible light. Probably easier to just setup a LINAC and slam electrons into an appropriate target. Or fire a megafast highpower laser onto some gold. Pyroelectric crystals look pretty cool too, but information is scant so far.
I'm not very clear on the laser+gold target method. 1.022meV corresponds to 1.21pm light (for photon-nucleus pair production; 511keV = 2.42pm, for photon-photon pair production). I was assuming that, like the photoelectric effect, frequency of light was the important factor not intensity. I can't (quickly) find construction details for the Titan laser, but it looks like it's TI:Sapphire, so its not producing extremely hard x-rays. Is this some non-linear effect achievable even with visble/UV light, provided you can dump enough power in a small enough time and space? Would seem to be what they're saying with: "When a short pulse with intensity greater than 10^19 watts per square centimeter strikes a target, electrons with energies up to 3 megaelectronvolts are created."
From another article about Titan, specifically about positron creation: "As they move close to the gold nucleus, the electrons each break apart into a lower-energy electron and its anti-matter opposite, a positron. The high-energy electrons would naturally break down into matter and anti-matter pairs; the gold simply speeds up the transformation."
I'm really not sure what physical process they're talking about there, anyone have a clue? Still, seems plausible that electrons accelerated to 3meV could be involved in pair production somehow, since it only requires double the rest mass/energy of an electron (511keV*2). Could it just be the idea from above: The 3meV electron transitions to a lower state, letting out a 1.022meV x-ray which triggers the pair production?
Now, skipping ahead to when you have your petawatt laser facility completed, we need to consider storage of your positrons next. An ultra-hard vacuum, materials that won't out-gas at all, and some serious trapping fields. Actually, sounds easier than the laser ;) Then we can work on the anti-proton facility next-door, and we'll have anti-hydrogen in no time. At which point i propose we start working on fusion of anti-hydrogen for the production of heavier anti-elements. Once we get upto anti-carbon, we can construct some microscopic circuit elements and study positron current flow, which i think would be Too Cool For School.
We're only a few steps away then from harnessing the positron flow from my singularity reactor concept. (feed matter to a micro-singularity to produce jets of 1.022meV photons for pair-production, and divert the resultant charged particles to the (matter and antimatter) loads. Then let them annihilate on the other side, and use a yet-to-be-discovered way of harnessing work from compton scattering by the resulting 511keV photons. Once the photon's have scattered down to UV energies, they're directed through layers of photovoltaic nanoantennae. Talk about energy efficiency. I'm betting the artificial singularity warpcore in romulan warbirds worked along those lines ;) )
Back to reality now. To detect any possible gamma rays from a discharge, looks like the prevailing technique is still scintillators and photomultiplier tubes (or avalanche photodiodes) as in PET scanners.
I think if you could get the discharge from your 28KJ bank to mimic a lightning bolt, it would probably be worth looking for super-high-energy photons. Aren't Marx generators typically used to simulate lightning though? (Maybe a more convenient and efficient route for the search?)
</Armchair Nuclear Physicist Off>
Re: Antimatter Gamma Ray Bursts
plazmatron, Thu Nov 26 2009, 05:04PM
There are two possible sources of positrons in a lightning storm.
The first is high energy heavy ion collisions in the upper atmosphere directly above the stroke itself ( "jets" and "sprites"),
that may produce positrons.
The second is that is was recently postulated that lightning storms may be induced by cosmic rays, which will happily produce positrons, along with other subatomic bric-a-brac.
Les
plazmatron, Thu Nov 26 2009, 05:04PM
There are two possible sources of positrons in a lightning storm.
The first is high energy heavy ion collisions in the upper atmosphere directly above the stroke itself ( "jets" and "sprites"),
that may produce positrons.
The second is that is was recently postulated that lightning storms may be induced by cosmic rays, which will happily produce positrons, along with other subatomic bric-a-brac.
Les
Re: Antimatter Gamma Ray Bursts
Proud Mary, Thu Nov 26 2009, 07:57PM
Setting aside the origin of any gamma ray bursts detectable at ground level, I see it as being no easy matter for even the well equipped amateur to distinguish them from terrestrial gamma rays, or even from cosmic muons also arriving from skyward.
Vertical stacks of coincidence counters could demonstrate that the rays came from skyward, and if one filtered out the gamma rays from one stack by shielding it under a lead block so that only muons could be detected , then one could compare the output of this with an unshielded stack, and infer the relative ratios of gamma rays and muons coming from skyward.
But attempting to measure their energy seems very much more difficult without sophisticated and costly equipment.
If these gamma ray phenomena are relatively infrequent, then the task would be more difficult still.
It's not something on which I'd have the time, money or skill to attempt.
Proud Mary, Thu Nov 26 2009, 07:57PM
Setting aside the origin of any gamma ray bursts detectable at ground level, I see it as being no easy matter for even the well equipped amateur to distinguish them from terrestrial gamma rays, or even from cosmic muons also arriving from skyward.
Vertical stacks of coincidence counters could demonstrate that the rays came from skyward, and if one filtered out the gamma rays from one stack by shielding it under a lead block so that only muons could be detected , then one could compare the output of this with an unshielded stack, and infer the relative ratios of gamma rays and muons coming from skyward.
But attempting to measure their energy seems very much more difficult without sophisticated and costly equipment.
If these gamma ray phenomena are relatively infrequent, then the task would be more difficult still.
It's not something on which I'd have the time, money or skill to attempt.
Re: Antimatter Gamma Ray Bursts
, Fri Nov 27 2009, 04:38AM
If you wanted to see if you were having pair production you need to use a coincidence detection system like someone mentioned that is used for PET scans. To make antimatter (positrons) you just need 1.022MeV photons and sometimes they would have a collision and pair production would result. You could make those with a MV marx generator a vacuum diode and a high Z target. Some of them would probably interact with something and make positrons. You could also do it with an ultrahigh intensity laser, the electrons in the field become relativistic and these could be used to make high energy photons. Or you can make really high energy electrons in a laser wakefield accelerator, but I dont think any home experimenter can build one of those lasers.
, Fri Nov 27 2009, 04:38AM
If you wanted to see if you were having pair production you need to use a coincidence detection system like someone mentioned that is used for PET scans. To make antimatter (positrons) you just need 1.022MeV photons and sometimes they would have a collision and pair production would result. You could make those with a MV marx generator a vacuum diode and a high Z target. Some of them would probably interact with something and make positrons. You could also do it with an ultrahigh intensity laser, the electrons in the field become relativistic and these could be used to make high energy photons. Or you can make really high energy electrons in a laser wakefield accelerator, but I dont think any home experimenter can build one of those lasers.
Re: Antimatter Gamma Ray Bursts
LutzH, Fri Dec 04 2009, 02:56AM
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 :)
LutzH, Fri Dec 04 2009, 02:56AM
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 :)
Re: Antimatter Gamma Ray Bursts
GhostlyFigures, Wed Mar 03 2010, 03:19PM
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 :)
GhostlyFigures, Wed Mar 03 2010, 03:19PM
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 :)
Re: Antimatter Gamma Ray Bursts
Proud Mary, Sun Mar 07 2010, 11:56AM
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 μs 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.
Proud Mary, Sun Mar 07 2010, 11:56AM
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 μs 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.
Re: Antimatter Gamma Ray Bursts
Conundrum, Sun Mar 07 2010, 01:32PM
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
Conundrum, Sun Mar 07 2010, 01:32PM
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
Re: Antimatter Gamma Ray Bursts
Proud Mary, Sun Mar 07 2010, 02:14PM
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 ≈60 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 © 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. 34–42.
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.
Proud Mary, Sun Mar 07 2010, 02:14PM
Conundrum wrote ...
interesting...
This suggests that X-rays could be generated using a Marx generator with no vacuum tube needed.
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 ≈60 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 © 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. 34–42.
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.
Re: Antimatter Gamma Ray Bursts
Conundrum, Mon Mar 08 2010, 08:18AM
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
Conundrum, Mon Mar 08 2010, 08:18AM
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
Re: Antimatter Gamma Ray Bursts
Proud Mary, Mon Mar 08 2010, 04:05PM
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,∗, Cinthia M.S. Magalhãesa,b, Jonas O. Silvaa,b, João 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 – 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.
Proud Mary, Mon Mar 08 2010, 04:05PM
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
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,∗, Cinthia M.S. Magalhãesa,b, Jonas O. Silvaa,b, João 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 – 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.
Re: Antimatter Gamma Ray Bursts
Conundrum, Thu Mar 11 2010, 07:22PM
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
Conundrum, Thu Mar 11 2010, 07:22PM
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
Re: Antimatter Gamma Ray Bursts
Proud Mary, Thu Mar 11 2010, 08:09PM
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)
Proud Mary, Thu Mar 11 2010, 08:09PM
Conundrum wrote ...
hmm... aluminised mylar?
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)
Re: Antimatter Gamma Ray Bursts
Conundrum, Fri Mar 17 2017, 02:48PM
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.
Conundrum, Fri Mar 17 2017, 02:48PM
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.
Re: Antimatter Gamma Ray Bursts
Proud Mary, Mon Apr 10 2017, 07:47PM
X-rays are produced by HV sparks in air at atmospheric pressure - but you have to have specialised kit to detect and measure them.
J. Geophys. Res., 113, D23207,
doi:10.1029/2008JD010315.
A study of X-ray emission from laboratory sparks in air at atmospheric pressure
Dwyer, J. R., Z. Saleh, H. K. Rassoul, D. Concha, M. Rahman, V. Cooray, J. Jerauld, M. A. Uman, and V. A. Rakov
Received 23 April 2008; revised 17 July 2008; accepted 25 September 2008; published 9 December 2008.
[1] 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 ms 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.
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.
Proud Mary, Mon Apr 10 2017, 07:47PM
X-rays are produced by HV sparks in air at atmospheric pressure - but you have to have specialised kit to detect and measure them.
J. Geophys. Res., 113, D23207,
doi:10.1029/2008JD010315.
A study of X-ray emission from laboratory sparks in air at atmospheric pressure
Dwyer, J. R., Z. Saleh, H. K. Rassoul, D. Concha, M. Rahman, V. Cooray, J. Jerauld, M. A. Uman, and V. A. Rakov
Received 23 April 2008; revised 17 July 2008; accepted 25 September 2008; published 9 December 2008.
[1] 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 ms 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.
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.
Re: Antimatter Gamma Ray Bursts
Conundrum, Wed Apr 19 2017, 09:42AM
Intriguing!
But yes, making antimatter *in bulk* would tend to suggest society has advanced beyond the need for nuclear deterrence, as we would be an interstellar species by then.
Conundrum, Wed Apr 19 2017, 09:42AM
Intriguing!
But yes, making antimatter *in bulk* would tend to suggest society has advanced beyond the need for nuclear deterrence, as we would be an interstellar species by then.
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