Ggthjy

Signed and unsigned numbers

Getting the || sign while using Kurier

What is better: yes / no radio, or simple checkbox?

This Alpine town?

Why restrict private health insurance?

How to write a chaotic neutral protagonist and prevent my readers from thinking they are evil?

Can't make sense of a paragraph from Lovecraft

Does "Until when" sound natural for native speakers?

In the late 1940’s to early 1950’s what technology was available that could melt ice?

How do I print a field from the bibliography

What are you allowed to do while using the Warlock's Eldritch Master feature?

Having the player face themselves after the mid-game

Virginia employer terminated employee and wants signing bonus returned

Confusion about Complex Continued Fraction

Why does Solve lock up when trying to solve the quadratic equation with large integers?

Why do phishing e-mails use faked e-mail addresses instead of the real one?

What is the generally accepted pronunciation of “topoi”?

Power Strip for Europe

Doubts in understanding some concepts of potential energy

Which situations would cause a company to ground or recall a aircraft series?

Making a kiddush for a girl that has hard time finding shidduch

What is this diamond of every day?

What will be the sign of work done?

Do cubics always have one real root?

Possible to detect presence of nuclear bomb?

Is it Possible to Determine Radiation Levels Using Satelites?Is there a way to decrease the rate of nuclear Beta decay?How to detect radiation on the metal (coin)?Any real life demonstrations of radioactive decay?How would the explosion from a Pure Fusion Bomb differ from the explosion from a Fission Nuclear Bomb?Complex structures bound by nuclear forces ( nuclear molecules ?)In the Iranian nuclear deal, how can IAEA detect nuclear activity after 24 days?Meaning of 'nuclear surface vibrations'?Nuclear bomb power - myth?What is the spectrum of a nuclear bomb in a vacuum?Have we found all stable nuclear isomers?

3

$begingroup$

Take, for instance, a W-80 nuclear warhead. Does technology exist, say in the form of a satellite or drone, that could detect the warhead's presence (assuming it's not enclosed in some kind of shielding)?

nuclear-physics radiation radioactivity

share|cite|improve this question

edited 25 mins ago

Qmechanic♦

106k121941214

asked 50 mins ago

birdusbirdus

1314

$endgroup$

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  Related: physics.stackexchange.com/q/6906. Short version: it's always enclosed in the shielding provided by the atmosphere.
  $endgroup$
  – dmckee♦
  43 mins ago
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  Thanks for that link, @dmckee.
  $endgroup$
  – birdus
  38 mins ago
  

  
  
  
  

add a comment | 

3

$begingroup$

Take, for instance, a W-80 nuclear warhead. Does technology exist, say in the form of a satellite or drone, that could detect the warhead's presence (assuming it's not enclosed in some kind of shielding)?

nuclear-physics radiation radioactivity

share|cite|improve this question

edited 25 mins ago

Qmechanic♦

106k121941214

asked 50 mins ago

birdusbirdus

1314

$endgroup$

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  Related: physics.stackexchange.com/q/6906. Short version: it's always enclosed in the shielding provided by the atmosphere.
  $endgroup$
  – dmckee♦
  43 mins ago
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  Thanks for that link, @dmckee.
  $endgroup$
  – birdus
  38 mins ago
  

  
  
  
  

add a comment | 

$begingroup$

Take, for instance, a W-80 nuclear warhead. Does technology exist, say in the form of a satellite or drone, that could detect the warhead's presence (assuming it's not enclosed in some kind of shielding)?

nuclear-physics radiation radioactivity

share|cite|improve this question

edited 25 mins ago

Qmechanic♦

106k121941214

asked 50 mins ago

birdusbirdus

1314

$endgroup$

share|cite|improve this question

edited 25 mins ago

Qmechanic♦

106k121941214

asked 50 mins ago

birdusbirdus

1314

share|cite|improve this question

edited 25 mins ago

Qmechanic♦

106k121941214

asked 50 mins ago

birdusbirdus

1314

edited 25 mins ago

Qmechanic♦

106k121941214

edited 25 mins ago

Qmechanic♦

106k121941214

asked 50 mins ago

birdusbirdus

1314

asked 50 mins ago

birdusbirdus

1314

1 Answer
1

active

oldest

votes

3

$begingroup$

No. It's not even possible to detect one that's inside a suitcase or a shipping container. There's a famous story about how a senator asked Oppenheimer in 1946 whether terrorists could blow up New York this way, or whether there was any tool that could detect the bomb when it was brought into the country. Oppenheimer famously replied, "a screwdriver" -- meaning that you would have to open the box to find out.

Although considerable effort has been dedicated since then to trying to improve detection techniques, highly enriched uranium (HEU) is particularly difficult to detect. It only emits alpha particles, and therefore all you have to do is wrap it in newspaper, and its radiation becomes undetectable.

The APS has a publicly available report on this topic, which goes into some of the physics. There are passive and active methods. Active means that you do something to the material in order to test it, as opposed to just trying to detect the radiation that it's putting out. Re passive detection of HEU:

Currently, passive detection is accomplished primarily by observation of either neutrons and/or photons emitted by spontaneous fission and by photons emitted in radioactive decay and neutron capture. Highly-enriched uranium (HEU) emits a number of relatively intense low-energy gamma rays that are largely absorbed by the material itself and are easily absorbed by most surrounding materials. The more penetrating photons emitted are of low abundance. If the HEU contains reactor-irradiated material, significant contamination by 232U can be found that may be detected through the emission of the 2615-keV gamma ray in the decay of 208Tl. Emission of neutrons from highly enriched uranium (HEU) is quite weak because of the low rate of spontaneous fission.

There are active methods of detection, but they involve radiation that you can't expose people to.

share|cite|improve this answer

edited 15 mins ago

answered 40 mins ago

Ben CrowellBen Crowell

52.7k6162306

$endgroup$

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  There are various active tools for detecting concentrations of fissile materials in containers around these days. They are not generally good for biological systems, however, so you have to take the suitcase away from it's owner or scan a shipping container for human cargo before you run the tests.
  $endgroup$
  – dmckee♦
  36 mins ago
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  @dmckee If a guy had a W-80 in the trunk of his car, does any technology exist that could find him as he drove down the highway? Just trying not to sound like an idiot for the sake of my novel.
  $endgroup$
  – birdus
  32 mins ago
  
  
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  @birdus All the techniques I know of (x- and gamma-ray back scatter, neutron fluorescence, etc..) would imposes a non-trivial ionizing radiation dose on every person driving down the road. This stuff saw a huge jump in funding starting in 2002, but it's not a easy problem and the "working" systems all have a problem with false positives. They count on being able to re-scan more slowly when the big red light turns on to sort out real event from statistical fluctuations (which cause essentially all the positive results).
  $endgroup$
  – dmckee♦
  28 mins ago
  
  
  

  
  
  
  

add a comment | 

Your Answer

StackExchange.ifUsing("editor", function () {
return StackExchange.using("mathjaxEditing", function () {
StackExchange.MarkdownEditor.creationCallbacks.add(function (editor, postfix) {
StackExchange.mathjaxEditing.prepareWmdForMathJax(editor, postfix, [["$", "$"], ["\\(","\\)"]]);
});
});
}, "mathjax-editing");

StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "151"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);

StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});

function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: false,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: null,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
noCode: true, onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});


}
});

draft saved

draft discarded

Sign up or log in

StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});

Sign up using Google

Sign up using Facebook

Sign up using Email and Password

Post as a guest

Name

Email

Required, but never shown

StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fphysics.stackexchange.com%2fquestions%2f465777%2fpossible-to-detect-presence-of-nuclear-bomb%23new-answer', 'question_page');
}
);

Post as a guest

Name

Email

Required, but never shown

3

$begingroup$

No. It's not even possible to detect one that's inside a suitcase or a shipping container. There's a famous story about how a senator asked Oppenheimer in 1946 whether terrorists could blow up New York this way, or whether there was any tool that could detect the bomb when it was brought into the country. Oppenheimer famously replied, "a screwdriver" -- meaning that you would have to open the box to find out.

Although considerable effort has been dedicated since then to trying to improve detection techniques, highly enriched uranium (HEU) is particularly difficult to detect. It only emits alpha particles, and therefore all you have to do is wrap it in newspaper, and its radiation becomes undetectable.

The APS has a publicly available report on this topic, which goes into some of the physics. There are passive and active methods. Active means that you do something to the material in order to test it, as opposed to just trying to detect the radiation that it's putting out. Re passive detection of HEU:

Currently, passive detection is accomplished primarily by observation of either neutrons and/or photons emitted by spontaneous fission and by photons emitted in radioactive decay and neutron capture. Highly-enriched uranium (HEU) emits a number of relatively intense low-energy gamma rays that are largely absorbed by the material itself and are easily absorbed by most surrounding materials. The more penetrating photons emitted are of low abundance. If the HEU contains reactor-irradiated material, significant contamination by 232U can be found that may be detected through the emission of the 2615-keV gamma ray in the decay of 208Tl. Emission of neutrons from highly enriched uranium (HEU) is quite weak because of the low rate of spontaneous fission.

There are active methods of detection, but they involve radiation that you can't expose people to.

share|cite|improve this answer

edited 15 mins ago

answered 40 mins ago

Ben CrowellBen Crowell

52.7k6162306

$endgroup$

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  There are various active tools for detecting concentrations of fissile materials in containers around these days. They are not generally good for biological systems, however, so you have to take the suitcase away from it's owner or scan a shipping container for human cargo before you run the tests.
  $endgroup$
  – dmckee♦
  36 mins ago
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  @dmckee If a guy had a W-80 in the trunk of his car, does any technology exist that could find him as he drove down the highway? Just trying not to sound like an idiot for the sake of my novel.
  $endgroup$
  – birdus
  32 mins ago
  
  
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  @birdus All the techniques I know of (x- and gamma-ray back scatter, neutron fluorescence, etc..) would imposes a non-trivial ionizing radiation dose on every person driving down the road. This stuff saw a huge jump in funding starting in 2002, but it's not a easy problem and the "working" systems all have a problem with false positives. They count on being able to re-scan more slowly when the big red light turns on to sort out real event from statistical fluctuations (which cause essentially all the positive results).
  $endgroup$
  – dmckee♦
  28 mins ago
  
  
  

  
  
  
  

add a comment | 

3

$begingroup$

No. It's not even possible to detect one that's inside a suitcase or a shipping container. There's a famous story about how a senator asked Oppenheimer in 1946 whether terrorists could blow up New York this way, or whether there was any tool that could detect the bomb when it was brought into the country. Oppenheimer famously replied, "a screwdriver" -- meaning that you would have to open the box to find out.

Although considerable effort has been dedicated since then to trying to improve detection techniques, highly enriched uranium (HEU) is particularly difficult to detect. It only emits alpha particles, and therefore all you have to do is wrap it in newspaper, and its radiation becomes undetectable.

The APS has a publicly available report on this topic, which goes into some of the physics. There are passive and active methods. Active means that you do something to the material in order to test it, as opposed to just trying to detect the radiation that it's putting out. Re passive detection of HEU:

Currently, passive detection is accomplished primarily by observation of either neutrons and/or photons emitted by spontaneous fission and by photons emitted in radioactive decay and neutron capture. Highly-enriched uranium (HEU) emits a number of relatively intense low-energy gamma rays that are largely absorbed by the material itself and are easily absorbed by most surrounding materials. The more penetrating photons emitted are of low abundance. If the HEU contains reactor-irradiated material, significant contamination by 232U can be found that may be detected through the emission of the 2615-keV gamma ray in the decay of 208Tl. Emission of neutrons from highly enriched uranium (HEU) is quite weak because of the low rate of spontaneous fission.

There are active methods of detection, but they involve radiation that you can't expose people to.

share|cite|improve this answer

edited 15 mins ago

answered 40 mins ago

Ben CrowellBen Crowell

52.7k6162306

$endgroup$

• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  There are various active tools for detecting concentrations of fissile materials in containers around these days. They are not generally good for biological systems, however, so you have to take the suitcase away from it's owner or scan a shipping container for human cargo before you run the tests.
  $endgroup$
  – dmckee♦
  36 mins ago
  
  
  

  
  
  
  


• 
  
  
  

  
  

  
  
  
  
  
  

  
  $begingroup$
  @dmckee If a guy had a W-80 in the trunk of his car, does any technology exist that could find him as he drove down the highway? Just trying not to sound like an idiot for the sake of my novel.
  $endgroup$
  – birdus
  32 mins ago
  
  
  

  
  
  
  


• 
  
  
  

  
  1
  

  
  
  
  
  
  

  
  $begingroup$
  @birdus All the techniques I know of (x- and gamma-ray back scatter, neutron fluorescence, etc..) would imposes a non-trivial ionizing radiation dose on every person driving down the road. This stuff saw a huge jump in funding starting in 2002, but it's not a easy problem and the "working" systems all have a problem with false positives. They count on being able to re-scan more slowly when the big red light turns on to sort out real event from statistical fluctuations (which cause essentially all the positive results).
  $endgroup$
  – dmckee♦
  28 mins ago
  
  
  

  
  
  
  

add a comment | 

$begingroup$

No. It's not even possible to detect one that's inside a suitcase or a shipping container. There's a famous story about how a senator asked Oppenheimer in 1946 whether terrorists could blow up New York this way, or whether there was any tool that could detect the bomb when it was brought into the country. Oppenheimer famously replied, "a screwdriver" -- meaning that you would have to open the box to find out.

Although considerable effort has been dedicated since then to trying to improve detection techniques, highly enriched uranium (HEU) is particularly difficult to detect. It only emits alpha particles, and therefore all you have to do is wrap it in newspaper, and its radiation becomes undetectable.

The APS has a publicly available report on this topic, which goes into some of the physics. There are passive and active methods. Active means that you do something to the material in order to test it, as opposed to just trying to detect the radiation that it's putting out. Re passive detection of HEU:

Currently, passive detection is accomplished primarily by observation of either neutrons and/or photons emitted by spontaneous fission and by photons emitted in radioactive decay and neutron capture. Highly-enriched uranium (HEU) emits a number of relatively intense low-energy gamma rays that are largely absorbed by the material itself and are easily absorbed by most surrounding materials. The more penetrating photons emitted are of low abundance. If the HEU contains reactor-irradiated material, significant contamination by 232U can be found that may be detected through the emission of the 2615-keV gamma ray in the decay of 208Tl. Emission of neutrons from highly enriched uranium (HEU) is quite weak because of the low rate of spontaneous fission.

There are active methods of detection, but they involve radiation that you can't expose people to.

share|cite|improve this answer

edited 15 mins ago

answered 40 mins ago

Ben CrowellBen Crowell

52.7k6162306

$endgroup$

share|cite|improve this answer

edited 15 mins ago

answered 40 mins ago

Ben CrowellBen Crowell

52.7k6162306

answered 40 mins ago

Ben CrowellBen Crowell

52.7k6162306

answered 40 mins ago

Ben CrowellBen Crowell

52.7k6162306