Future Nuclear testing: pros and cons-2

[shiv]

Previous thread here: Future Nuclear testing: pros and cons-1
-Arun_S {Admin Hat on}
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Long time ago when I was reading this book (select pages also available on Google books:
[url=http://books.google.com/books?id=nkmQl_NrcgMC&dq=from+polaris+to+trident+the+development+of+us+fleet+ballistic+missile+technology+by+graham+spinardi&pg=PP1&ots=mrW-_jMV3U&sig=kbuhuvJYmehZV5ccJG5cb3K9re8&hl=en&prev=http://www.google.com/search%3Fq%3DFrom%2BPolaris%2Bto%2BTrident:%2BThe%2BDevelopment%2Bof%2BUS%2BFleet%2BBallistic%2BMissile%2BTechnology%2BBy%2BGraham%2BSpinardi%2B%26ie%3Dutf-8%26oe%3Dutf-8%26rls%3Dorg.mozilla:en-US:official%26client%3Dfirefox-a&sa=X&oi=print&ct=title&cad=one-book-with-thumbnail#PPA23,M1]From Polaris to Trident: The Development of US Fleet Ballistic Missile ...
By Graham Spinardi[/url][/i]

Is this what India would use too, or Botswana, if it had to make a TN bum.

Looking at the 2:1:4:6 ratio posted by LakshmiC - the "6" is tamper going boom What other tampers can be used if at all?

Open source says that some US nuclear warheads inject Tritium gas into thw core just before detonation. Storage of gas outside in this manner makes it unnecessary to service the core (which is necessary with cores filled with Li 6 Deuteride).The external Tritium gas can be replenished reqularly.

What was used in the single Indian test?

The following ref uses the deadly "S" word, "scalable" (bolded+underlined in the quote below) What does it mean?

http://fas.org/sgp//eprint/cardozo.pdf

[quote] For the secondary to be imploded by the hot, radiation-
induced plasma surrounding it, it must remain cool for the first
microsecond, i.e., it must be encased in a massive radiation (heat)
shield. The shield’s massiveness allows it to double as a tamper, adding
momentum and duration to the implosion. No material is better suited
for both of these jobs than ordinary, cheap uranium-238, which
happens, also, to undergo fission when struck by the neutrons produced
by D-T fusion. This casing, called the pusher, thus has three jobs: to
keep the secondary cool, to hold it, inertially, in a highly compressed
state, and, finally, to serve as the chief energy source for the entire
bomb. The consumable pusher makes the bomb more a uranium fission
bomb than a hydrogen fusion bomb. It is noteworthy that insiders never
used the term hydrogen bomb.

Finally, the heat for fusion ignition comes not from the primary but
from a second fission bomb called the spark plug, imbedded in the heart
of the secondary. The implosion of the secondary implodes this spark
plug, detonating it and igniting fusion in the material around it, but the
spark plug then continues to fission in the neutron-rich environment
until it is fully consumed, adding significantly to the yield.

The two-stage, radiation-implosion, Teller-Ulam superbomb is like
an ecosystem in which nothing is wasted. The pieces fit like a jigsaw
puzzle. Every component contributes to overall yield, often in more
than one way. Oppenheimer declared it “technically so sweetâ€

[satyarthi]

Looking at the 2:1:4:6 ratio posted by LakshmiC - the "6" is tamper going boom What other tampers can be used if at all?

The usual tamper is U238 (natural uranium). Which is normally difficult to bring to fission due to requirement of higher energy neutrons. But fusion fuel undergoing fusion can release lot of high energy neutrons which can fission the U238.

To make the tamper fission even more efficiently one can use U235 which fissions easily with a wide range of neutron energies. So any neutrons leaking from the fusion fuel, will cause a fission in the tamper.

U238 can be mixed with Pu so that U238 catches the high energy neutrons and fissions, while Pu can fission even with the low energy ones.

Thorium is also hard to fission normally but can be used as a fissionable tamper, although of lesser efficiency that U238.

For non fissionable tampers, any of the high atomic mass non-radioactive materials can be used, eg lead, bismuth, gold etc.

[shiv]

To make the tamper fission even more efficiently one can use U235 which fissions easily with a wide range of neutron energies. So any neutrons leaking from the fusion fuel, will cause a fission in the tamper.

U238 can be mixed with Pu so that U238 fissions with high energy neutrons, while Pu can fission with even the low energy ones. .

Isn't this the very stuff that comes right out of reactors?

[satyarthi]

U235 is the major component of the highly enriched uranium. Natural uranium is mostly U238 with little bit of U235 (<1%). The proportion of U235 in the fuel needs to be enhanced upto 4% by enrichment (say using centrifuges) prior to use in the reactors. Highly enriched U (>90% U235) is weapons grade.

Pu239 and U235 are the valuable ones. So their use in tampers eats into the weapons grade fissile stockpile.

[satyarthi]

One can call the fissile tamper/pusher as the 3rd stage. It all depends upon what one defines as stages. But in usual 2-stage Teller-ulam design, even the fissioning tamper/pusher is called as belonging to the "second stage".

So, if someone says that the Indian fusion device that was tested was a 2-stage device, doesn't necessarily mean it didn't have fissionable tamper.

The usual idea of making a staged TN design means using the power of the previous stage to compress the next stage to fusion.

So, a 3-stage TN weapon in that sense will use the primary to compress the secondary using x-rays from the primary. Then recalling that most of the power coming out of the secondary is from fission (including that of the tamper), one can then use the x-rays from the secondary to compress a tertiary stage to fusion.

The Russian 50Mt Tsar-Bomba had this kind of 3-stage design.

[Gerard]

What happens to a thermonuclear bomb in which you do not use u-238 as tamper. Is that neutron bum?

From wikipedia article on the RDS-220 (the Tsar-Bomba)

Developed by the Soviet Union, the bomb was originally designed to have a yield of about 100 megatons of TNT; however that was reduced by half in order to limit the amount of nuclear fallout that would result.

To limit fallout, the third stage had a lead tamper instead of a uranium-238 fusion tamper (which greatly amplifies the reaction by fissioning uranium atoms with fast neutrons from the fusion reaction). This eliminated fast fission by the fusion-stage neutrons, so that approximately 97% of the total energy resulted from fusion alone (as such, it was one of the "cleanest" nuclear bombs ever created, generating a very low amount of fallout relative to its yield).

When you go the other way, with U235 used instead of U238, the yield of the weapon is increased. It seems a number of US warheads use this method (replacing of rings around the secondary) to raise/lower yield of the secondary stage.

Of course, since the tritium boost gas injection can be controlled, that too can be used to limit the yield from the primary stage.

What appears to be an oralloy (HEU) ring can be seen in the drawing below

http://archive.greenpeace.org/comms/nukes/fig04.gif

http://archive.greenpeace.org/comms/nukes/fig05.gif
http://www.fas.org/sgp/eprint/morland_image037.gif
http://nuclearweaponarchive.org/Usa/Weapons/W80-0.jpg
http://nuclearweaponarchive.org/Usa/Wea ... handle.jpg
http://lanl.gov/history/hbombon/images/Fusion.gif

[enqyoobOLD]

quoting ramdas:

N^3,

I should have phrased it better. Once we have a 40000+MW power program dependent on imported yoo, lobby or no lobby it creates a wonderful handle for "FMCT now or no yoo, no 40000 MW" kind of pressure. This is something the nuclear deal's supporters have not addressed. Given our situation my feeling is that the civilian program should be moved forward to the maximum extent that does not negatively affect the military program It should not be allowed to develop a dynamic of its own that gives others a handle to affect the military program negatively.

Progress on FMCT is not written in as condition for fuel supply, so the above scenario is a violation of the agreement. The simple solution there is to give contracts to US companies for at least a few of those reactors, and in case of fuel supply contract violation, those companies lose all their assets in India. Also, all other parts of the agreement become haraam. Most such investments are 20-30year business plans. So citing this fear as a reason to diss the 123 just does not make any sense, sorry.

Regarding cruise missiles, the soviets were developing a hypersonic meteorit missile of ~4000km range. This was a big cruise missile weighing ~10 tons. So, an intercontinental cruise missile that is hypersonic might be quite large itself. Wont maneuvering RV's on a ballistic missile be much better ?with decoys chaff and other means of penetrating ABM defences ?

All ballistic missiles that have to go far enough that they have to reach Space and re-enter, are hypersonic (speed >> 5 times speed of sound). The "meteorit" sounds like a ballistic missile, not a "cruise" missile.

The "cruise" term means that aerodynamic lift is used to fly along relatively flat trajectories for a long distance, instead of "ballistic" which is like throwing a ball (thrust is all in the boost stage). Result is that "cruise" missiles can fly pretty low for long distance, and since thrust is distributed over the whole trip, the launch is not such a spectacular event (translation: seen from Space). Also, since aerodynamic flight is possible, large changes in the path are also possible (can start aimed at Lakshadweep and end up in Peshawar).

Here is the difference between ballistic and aerodynamic in terms of initial thrust:
1) Ballistic: Initial thrust must be > INITIAL weight.
2) Aerodynamic: Initial thrust need only be around 0.2 times the initial weight, or even less if air-launched.

Also, Mass Ratio (Initial total mass divided by final "payload" mass) is around 5 to 8 for aerodynamic flight, but is around 10 to 20 for ballistic, for such missions.

Because of aerodynamic control forces, final maneuvers can execute even a 180 degree turn (esp. good for Pakistani mijjiles) and hit a completely different target. Ballistic thingies cannot do anything like that, they fall out of the sky.

[shiv]

Random thoughts on information that I am continuously digging up from the net regarding what has been said about the S1 "partial burn" - "fizzle"

I am trying to make no hints or suggestions about what the real state may be but I am taking released public information at face value. but including in this "face value judgement" the notes that I took in RC's talk

RC said that S1 was "45 kilotons"

He said that 1 Kg of Lithium Deuteride if fuly used up should release 80 kilotons of fusion energy

The "post shot radioactivity" paper says that the yield was 50 +/- 10 kiotons
http://www.fas.org/nuke/guide/india/nuk ... 0-barc.htm

PK Iyengar is reported as saying:
http://insaf.net/pipermail/sacw_insaf.n ... 00526.html

Scientific data indicated that the core of hydrogen bomb had burnt only
partially, Iyengar said.

"We cannot stop here. We must continue testing with improved designs so
that there is total burn and fusion yield is higher," he said.

In an apparent reference to AEC chairman R Chidambaram and former
scientific advisor to Defence Ministry A P J Abdul Kalam, Iyengar said
"The two scientists in Shakti-II said we don't need any more tests.. I
don't agree. We need a peer review on the status of nuclear tests."

The hydrogen bomb design included two components- a boosted fission device
(a small atomic bomb) that triggered the secondary core of the hydrogen or
fusion bomb.

The boosted fissi released about 20 kilotons (KT) of energy that triggered
the fusion core that produced another 20 KT, giving a total yield of about
40 KT, Iyengar said.

This indicated that only about 400 grams of the fusion device had burnt,
leaving a considerable amount unburnt.

"There was only a partial burning. I doubt if a complete burn wave was
established," he commented, that one cannot make larger megaton devices
with such partial-burn type devices.

According to Iyengar, India needs to test more hydrogen and neutron bombs
with complete burning of the core before it signed the CTBT.

PKI says the boosted fission primary worked @ 20 Kilotons. He says fusion gave 20 more kt from burning of 400 grams of Li Deuteride.

In this Instance it appears to me that we cannot take LakshmiC's "2:1:4:6" ratios for this particular device without also saying that if the primary was 20 Kilotons, we should have got 10 from the spark plug, 40 from fusion and 60 from tamper - giving a total of 130 kilotons. If we say that the planned total was 130 kilotons and not 40 or 45 (or even 200 kt), it means that the tamper and spark plug did not work at all, but fusion gave a partial burn despite that. To my inexpert mind that sounds unlikely. The spark plug is designed to cause the fusion to work better, and help more efficient fission, and the tamper contributes a great deal.

It is likely that, as LakshmiC stated in his original post, those ratios are only representative values and do not hold for every design. It is unlikely that the Indian design was meant to give those particular ratios and therefore it is unlikely that we can use those ratios to plot a graph on a spreadsheet and predict anything with regard to S1, but I am willing to see a previously made spreadsheet and learn.

To me a fission:fusion ratio of 1:1 in any design is a strange value when every open source ref says that most of a TN bum is always fission.

There appears to be a lot that we don't know.But then - I'm no guru.



In at least one reference Bharat Karnad has said this:

http://www.india-seminar.com/2006/560/560 bharat karnad.htm

The ‘Shakti’ series of tests in 1998 proved only that the miniaturized 20 kiloton (KT) fission bomb design, first tested in 1974, is militarily serviceable. All the other weapon designs – the boosted fission and, especially, the thermonuclear – due to their ‘simultaneous triggering’ in Pokhran, produced confused multi-test explosion data sufficient to conclude that the fusion design, for instance, did not work because of partial thermonuclear burn – authoritatively established by crater morphology and excessive traces of lithium in the rock and soil samples extracted from the L-shaped tunnel deep underneath the Thar desert where the devices exploded. Moreover, data from just one, and that too failed, test involving the decisive thermonuclear device is simply insufficient to write a software package simulating fusion reaction, leave alone help in developing new and more innovative designs for thermonuclear warheads/weapons of different power-to-yield ratios to fit varying missile nose-cone geometries.

In short, should this nuclear deal be approved by the US Congress, India will be permanently stuck with a primitive nuclear arms inventory which can in no way propel India into the military great power ranks. President ClintonÂ’s Under Secretary of State John Holum in his Congressional testimony had declared this as the main aim of US nonproliferation policy, which the successor George W. Bush Administration has now achieved.

Also from the same source

The Indian N-arsenal, according to public sources, of some 80 or so ready 20 KT nuclear weapons, have all used the weapon-grade plutonium (WgPu) obtained mostly from CIRUS and Dhruva. But there are 10 tons of accumulated spent fuel from all the PHWRs operating in the country over the last three-odd decades. This spent fuel, containing heavier isotopes of plutonium (Pu 240, Pu 241, Pu 242), is ill-suited for weapons/warheads, among other drawbacks, because of the uncertainty of the yield of the weapons using this fissile material. In an absolute crisis, there may be no way out other than producing weapons with the spent PHWR fuel. But, surely, this is only a stop-gap, with the real solution lying in converting the spent fuel into WgPu by running it, to begin with, in the prototype fast breeder reactor (PFBR) which may not glitchlessly come on stream until, say, 2012. Moreover, the WgPu so obtained will need several years of ‘cooling off’ period before it can be handled to make weapons/warheads. All this requires time, and it is time the nuclear deal does not make available to India. In other words, India’s escape hatch will be shut tight.

[Gerard]

This spent fuel, containing heavier isotopes of plutonium (Pu 240, Pu 241, Pu 242), is ill-suited for weapons/warheads, among other drawbacks, because of the uncertainty of the yield of the weapons using this fissile material

http://arxiv.org/pdf/physics/0401110.pdf

[quote]
A short time before detonating the device, the pit is filled with a few grams of a deuterium-tritium (DT ) gas mixture at a pressure of a few tens of atmospheres. When the weapon is detonated, the pit and the case are imploded by the high explosives at the same time as the DT gas. As the pit collapses into a solid ball, the DT is compressed into a sphere of a few millimeter radius with a density tens of times greater than its normal solid-phase density. At the same time the fissile material is compressed to a few times its normal density and the fission chain reaction starts.

As the chain reaction develops the fissile materials begins to emit x-rays and neutrons which heat the DT at the center of the device. The temperature of this mixture of fusionable materials therefore rises at the same time as the temperature of the fissile material. This leads to a remarkable phenomenon which is the cause
of the boosting process: the fusion fuel ignites before the fission chain reaction is terminated [22].

Therefore, at a time when the diverging chain reaction has generated a yield that is still negligible, the DT mixture burns out very quickly and generates a very intense pulse of high-energy neutrons by the thermonuclear reaction: D + T −→ 4 He + n .

These fusion neutrons interact with the fissile material, causing it to fission, and therefore to generate most of the yield of the explosion. In other words, with boosting, the yield of a fission explosive is controlled by the very fast neutron burst from the thermonuclear reactions: the fissile material (apart from heating the fusion fuel to ignition) is essentially a passive neutron and energy amplifier in the final stage of the nuclear explosion. This leads to several important conclusions:

1) With boosting, it is possible to build a relatively high yield fission explosive which is fairly compact because it uses only a relatively small amount of high explosives to implode the fissile material. The device can also be made relatively light-weight because a thick neutron reflector and/or a heavy tamper surrounding the fissile material are not necessary.

2) In an actual weapon, before arming the device, the DT mixture, or just the tritium, is stored outside of the pit in a separate reservoir. This facilitates maintenance and insures that boosting will not happen in case of an accidental detonation of the high explosives. Since the amount of high explosives needed to implode a boosted-device is only on the order of a few kilograms, a boosted fission-weapon is extremely safe because an accidental nuclear explosion is almost impossible to take place. This increased safety is the most important single factor which enabled so many nuclear weapons to be deployed for so many year. It is also the main reason why threshold nuclear States such as India, Israel, Pakistan, and North Korea rely on tritium-boosting technology to maintain a credible nuclear arsenal

3) The most important technical aspects of boosting (e.g., that during the implosion of the pit by chemical explosives the fusion fuel gets sufficiently compressed without mixing with the fissile material) can be tested without actually starting fission or fusion reactions. This can be done outside of the scope of the CTBT, and only requires conventional equipments that are available in most high-explosive research laboratories.

4) Using boosting, it is straightforward to build highly efficient and reliable fission weapons using reactor-grade plutonium. In particular, the possibility of a preinitiation of the chain reaction, which creates difficulties in making a non-boosted fission bomb [24, 25], is no longer a serious problem. In fact, two of
the five devices tested by India in May 1998 are believed to have used plutonium that was not classified as weapons grade [26]. Moreover, independently of the type of fissile material used, the construction of “simpleâ€

[enqyoobOLD]

shiv: 3 points from those:
1. P. Iyengar:

"he commented, that one cannot make larger megaton devices with such partial-burn type devices. According to Iyengar, India needs to test more hydrogen and neutron bombs with complete burning of the core before it signed the CTBT. "

No argument with that, but... questions is the need for megaton weapons compared to need for many other things.

2. Karnad's point seems to be that developing weapons with WgPu will take a lot of time after the FBRs come on line, and "India's escape hatch is shut tight" with this deal.

But did the eventual 123 deal actually "shut the escape hatch"? As I read it, it said nothing about what India can or cannot do in the strategic sector, and the FBRs are in the strategic sector, not in the "full-scope inspection" etc. The only thing that might trigger boycotts, fuel cut-offs etc, is a LIVE (super-critical) test. So this article or its thinking may be dated post-Hyde but pre-123? The Hyde act had all sorts of "recommendations" on poking Unkil's nose and "certifications" etc., none of which appeared in the 123.

3. Also, returning to P. Iyengar and Karnad, if India solves the question of how to establish the full "burn wave" etc., in a National Ignition Facility, away from prying eyes, then I would say that is the way to get enough data to write simulation / design software etc.

To get there, India needs hi-power, short-pulse lasers, very high-powered magnetic confinement etc. It gets back the "EOS" (Equation of State) determination at extreme conditions, plus the determination of nuclear reaction rates, scattering and absorption characteristics of different media under extreme conditions. Many years of intense research in controlled facilities. These things become quite a bit easier with the resources and technology made available (or at least freed up) with the deal.

Let's see about "testing". Of course, if you test the complete weapon exactly as it will be after surviving storage, transport, attachment, launch, transit through the atmosphere, space (vacuum) transit, the forces and buffeting of re-entry, and final triggering at 3000 or 200 meters, then I agree that beats any simulation or extrapolation. How you gonna do that? Put a nuke on an Agni and test in the Indian Ocean?

Then how do you collect data? As far as I know, data signals from sensors INSIDE the package will not reach any receiver before the blast of gamma rays will, so this won't work. So then the data must come from
a) Integral Equation solution - you get the effect measured at many points all round the explosion, far away, and try to solve for what must have caused that received signal. Tomographic reconstruction, like a CAT scan, except that it occurs in an extremely fast process.

b) post-blast analysis of crater size, lithium deposits, residual radioactivity, signs of high heating rates (glass), etc. etc.

The US even placed other ships, tanks, jeeps, houses etc. in the explosion vicinity to get "data" on destructive power. In the 1950s.

But today, like it or not, there is a huge cost to doing these sorts of things, which may be quite as bad as the effect of a few nuclear strikes on our cities, which is what we are trying to deter. At least, a nuke strike on certain cities would effect a long-needed cleanup, but the effect of conducting live tests would not even include this benefit. So! We must seriously look at alternatives.

OTOH, if ppl think they can get all this knowledge just by passive data collection from fission/fusion reactions conducted in pits in the desert, India should send spacecraft to the Sun. Much longer period of observation, and there is no fear of "partial burn", "fizzle" etc. DAta can come until the craft itself is shaheed - which may happen at some 5000 Celsius, deep into the outer fusion layer of the Sun (insides are actually believed to be cooler, only around 2000C). This is what I suggested, but unfortunately I also suggested how to make "dual-use" commercialization by taking some 1-way Space Tourists on it (i.e., Pakis). Ppl seemed to have missed this argument in their hurry to take offence, etc.

[shiv]

For completion - despite new posts from Gerard and enqyoob:
http://www.hinduonnet.com/thehindu/2000 ... 132523.htm

According to Dr. Iyengar, the thermonuclear explosion did not fully reach its planned potential. He gives credit to the scientists, who could get a thermonuclear burn to start, in the limited explosive size which was used. He also conclusively argues that the burn having taken place, the totality of the thermonuclear process was inadequate to provide conclusive data for use in the weaponising process. The partial explosion was insufficient as a basis for manufacturing fusion warheads. Experience in the development of thermonuclear weapons clearly shows that data in greater quantity and quality is necessary to move from the explosion stage to warhead manufacturing. This could not have been available from the Pokhran thermonuclear test. Dr. Iyengar's essential conclusion is that if India wants thermonuclear weapons, they cannot be had without more tests.
The Government officially released a nuclear doctrine. But faced with some well-founded critique of that document, it retracted to say it was a draft doctrine. Some in the group which drafted the document now call it a provisional doctrine. In a significant interview to this newspaper, the Foreign Minister, Mr. Jaswant Singh, further diluted some elements of the doctrine. As of now, there is no official explanation of where the Government stands vis-a-vis the nuclear doctrine. If it disassociates itself from it, India will apparently have no doctrine even as the Government possesses nuclear weapons. If the Government endorses the doctrine, more tests will be needed to make it viable.
The Indian nuclear doctrine is based on thermonuclear capability. That alone can provide the basis of a triad which the doctrine demands. The size of the nuclear arsenal needed to sustain a no- first-use pledge, which the Government has already taken, cannot be obtained without thermonuclear weapons. The assessed volume of India's processed nuclear weapons-grade fuel can only sustain the needed arsenal through a thermonuclear ability. The Government has also given an undertaking of a moratorium on further tests. Its single thermonuclear test was on, the other hand, inconclusive. It, therefore, appears that the nuclear doctrine cannot be implemented without further tests. Under the circumstances, the Government's moratorium will be viewed with circumspection at the least and with suspicion at worst. If it goes back on its word, it would irretrievably harm its credibility.

[Gerard]

questions is the need for megaton weapons compared to need for many other things.

A one time demonstration?
Dr Tim Hoyt has suggested on BRF that a 1 megaton test yield would conclusively demonstrate Teller Ullam rather than boosting or a Sloika.

[enqyoobOLD]

Response to that one, shiv, is that its the doctrine that must be changed. The doctrine of NFU, based on a thermonuke retaliation, is IMHO far less credible than even a doctrine of NFU based on widely dispersed genocide by hundreds of small devices. In the case of the US-Soviet pleasantries, the MAD equation was different. Huge land areas, concentrated population centers and hardened C^3 facilities demanded thermonukes. Pakistan and China don't, and I can't even think of anyone else against whom India might even consider using thermonukes.

Note that the US doesn't think MAD with 4000 thermonukes even deters North Korea or Iran. This is the apparent rationale for the BMD placed in Alaska, Pacific islands etc.

Gerard: Thanks. Looks like it's the final hardware design and construction that remains unverified for a "dial-a-yield" tritium-boosted weapon (agree that this is important, but not so important as to justify the national disaster that a test today will imply). Other elements can all be tested in contained nuclear facilities or in non-nuke explosions.

Also, the "large conventional explosion" on the North Korea-China border now makes a lot of sense.

[Gerard]

WTF?
How often does google traverse BRF?

Just did a search to see if I could dig up Tim's comment on BK's megaton demand and I saw the post I made a few minutes before...

[enqyoobOLD]

.. once again proving the supremacy of Pingreji as the Lingua Pak-a to be used in such discussions.

[p_saggu]

From Wikipedia Boosted Fission Weapons

This kind of thermonuclear weapon can produce up to 20% of its yield from fusion, with the rest coming from fission and is limited in yield to less than one megaton of TNT (4 PJ) equivalent. Joe-4 yielded 400 kilotons of TNT (1.7 PJ). In comparison, a true hydrogen bomb produces typically 50% of its yield from fusion, with 97% having been achieved, and there is no upper limit to its explosive yield.

Here is the 1:1 ratio, and the less than 1 megaton upper limit for a boosted fission weapon. I know wiki ain't exactly bhrama-satya, but...

[John Snow]

Ha I am glad to see enqyoob saar is seeking the fundamental truth,

Every day I see the same problem even in the land of milk and honey

Where is the vision?
Lost in Business
Where is business?
Lost in information
Where is information?
Lost in one up man ship.

First and foremost there must be an understanding in all parties what is India's role in South Asia, IOR, South China sea, Arabian peninsula, visa vi PRC, hyper power...etc

What are our goals in the next decade in strategic affairs, economy world trade, world resources etc (economic strategy?)

Are we in defensive offensive mode? Are we offensive defensive mode in the next decade, next two decades, next fifty years?

We are declared nuclear power; unless some aya ram gaya ram PM or puppet PM of fake coalition decides to go the SA, Ukraine, Kazak way and surrender the option without realizing we have two nuke adversaries breathing down our neck, for sure we are in big trouble

[Gerard]

http://arxiv.org/pdf/physics/0401110.pdf

[quote]Referring to Fig.3, the Teller-Ulam method is as follows: a fission bomb and a container filled with fusion fuel (the secondary) are placed within a common enclosure (the radiation case); while the radiation case and the envelope of the secondary (the pusher/tamper) are made of heavy materials opaque to x-rays, the
remaining space within the radiation case (the hohlraum) is filled with light-weight materials transparent to x-rays; as the primary fissions, large amounts of x-rays are radiated ahead of blast and instantaneously fill the hohlraum; x-ray radiation trapped within the hohlraum rapidly turns the hohlraum filling into a hot plasma;
radiation-driven thermalization insures that this plasma has very uniform pressure and temperature so that its effects on the secondary are the same from all sides; the plasma reradiates longer wavelength x-rays that are absorbed by the surface of the
secondary; the surface of the secondary (the pusher/tamper) is heated to the point where it vaporizes and material is ejected from it; the material ablated from the pusher/tamper causes by reaction a pressure which pushes it inwards, imploding the fusion fuel to very high densities.

This satisfies condition (a). Condition (b), ignition, is achieved by an optional element not yet discussed: the sparkplug at the center of the secondary in Fig.3. It consists of a subcritical amount of fissionable material compressed at the same time as the secondary. Because of the intense neutron background resulting from the explosion of the primary, a fission chain reaction starts in the sparkplug as soon as it becomes critical (in order to avoid a fizzle, and to maximize the yield from the sparkplug, it is generally boosted by a small amount of DT , on the order of 10 grams). Hence, with a careful design, the sparkplug will explode just when the thermonuclear fuel is imploded to its maximum density. It will then provide, in the form of x-rays, neutrons and additional compression from within, a large amount of energy sufficient to insure that ignition will start even in the worst case.

Once the fusion reaction starts, the fusion fuel (e.g., liquid deuterium in the first H-bomb, dry deuterated lithium (Li6 D) in the modern H-bombs, possibly liquid deuterium-tritium in “neutron bombs,â€

[enqyoobOLD]

What are our goals in the next decade in strategic affairs, economy world trade, world resources etc (economic strategy?)

Win nashunul elecshun in 2009. Win state elecshuns in 2010. Go to sleep on job. Beyond that, Bhavitavyam Bhavedeva. All is Maya. We are like that onlee.

The West may have Teller-Ullam. We have Hear-Nothing-Say-Nothing-See-Nothing-Smell-Everything and Laloo-Ulloo.

[shiv]

[quote="Gerard"]http://arxiv.org/pdf/physics/0401110.pdf Finally, by chosing for the pusher/tamper an appropriate heavy material it is possible to control the total yield of a thermonuclear weapon. This is because
the high-energy (i.e., 14 MeV) neutrons produced by fusion have sufficient energy to fission any kind of transuranic material such as all isotopes of uranium and plutonium. Therefore, while the minimum yield of a given thermonuclear design will be provided by using a non-fissionable heavy material such as lead or bismuth
as the tamper, the use of depleted (i.e., mostly isotope 238), natural, or highly enriched (i.e., mostly isotope 235) uranium will provide a range of increasing yields because more and more fission reactions will be produced in the tamper.

This is why the pusher/tamper is sometimes called the “third-stageâ€

[Gerard]

"Teller-Ulam-Sakharov-Zeldovitch design" as opposed to the Sloika layer cake design is scalable.

Whereas there are limits to how much interlaying of fission and fusion fuel one can do (and still have burn), with a true staged weapon, you don't have this (until the bomb itself becomes too large to deliver)

Staging provides scalability. You add a third stage and get an even bigger bomb. Or use several third stages that are all ignited by the second stage (itself ignited by the first).

Take a look at this photo of the B61 bomb
http://en.wikipedia.org/wiki/Image:B-61_bomb_(DOE).jpg
Notice the actual TN device on the table.

That similar package is the basis for the W80
http://en.wikipedia.org/wiki/Image:W80_ ... arhead.jpg

Now look at this LLNL page.

http://lanl.gov/history/hbombon/weapondev.shtml

Look what they are calling a primary. Looks like an entire W80 TN warhead. Look at its placement in the RV.

[shiv]

In fact Gerard I was asking about the role of tamper in varying the yield of the simple two stage design and not the addition of multiple fusion stages as in the "tsar bomba" type bomb.

[Gerard]

Well, the article by Gsponer and Hurni is an excellent primer in all this.

Interestingly RC in his article THE MAY 1998 POKHRAN TESTS: Scientific Aspects quoted from an earlier paper by Gsponer and Hurni.

[shiv]

Well, the article by Gsponer and Hurni is an excellent primer in all this.
.

In fact page 26 of the 2008 paper you linked has confirmed one more fact I thought I had read somewhere else.

The spark plug is optional, depending on what is needed to be achieved.

[Gerard]

See his article Fourth Generation Nuclear Weapons: Military effectiveness and collateral effects.

in Articles by A. Gsponer

[quote]Most of the yield of thermonuclear weapons is produced in a “third stageâ€

[Arun_S]

[quote="Gerard"]http://arxiv.org/pdf/physics/0401110.pdf

[quote]This is why using plutonium for the “third stageâ€

[Chandi Prasaad]

Long time ago when I was reading this book (select pages also available on Google books:
[url=http://books.google.com/books?id=nkmQl_NrcgMC&dq=from+polaris+to+trident+the+development+of+us+fleet+ballistic+missile+technology+by+graham+spinardi&pg=PP1&ots=mrW-_jMV3U&sig=kbuhuvJYmehZV5ccJG5cb3K9re8&hl=en&prev=http://www.google.com/search%3Fq%3DFrom%2BPolaris%2Bto%2BTrident:%2BThe%2BDevelopment%2Bof%2BUS%2BFleet%2BBallistic%2BMissile%2BTechnology%2BBy%2BGraham%2BSpinardi%2B%26ie%3Dutf-8%26oe%3Dutf-8%26rls%3Dorg.mozilla:en-US:official%26client%3Dfirefox-a&sa=X&oi=print&ct=title&cad=one-book-with-thumbnail#PPA23,M1]From Polaris to Trident: The Development of US Fleet Ballistic Missile ...
By Graham Spinardi[/url][/i] Somewhere in the beginning few chapters you will find reference on how the weight of the TN weapon was significantly reduced by use of tertiary stage that used enriched fissile material (Oralloy) for 3rd stage. This was the (simple) breakthrough that allowed the sub launched missile to achieve the range. while the 500kT comfortably met the minimum yield reqmt of 300kT.

High enriched 3rd stage has since become the std mantra for all countries that deployed TN weapons.

I just opened my book and found that on page 54.

Is this what India would use too, or Botswana, if it had to make a TN bum.

Yes if Botswana wants to usefully deter rather than argue for compassion in understanding its low yield pure fusion TN deterrence.

[enqyoobOLD]

So now the case for renewed testing is that the dial-a-yield did not yield enough to vaporize the nearby village? From the S1 discussion, if you add Dr. P. Iyengar's arguments, you conclude that had S1 "lived up" to "full burn" the yield would have been some 80kT, wiping out that village. Doesn't this at least say something about the success (I'd say utter bravado) of dial-a-yield? There is also the argument that S1 left traces of lithium whatever. But then we hear that 50% "burn" of the fuel is optimistic even on full-fusion weapons. Since the burn percentage of the fusion gas is so uncertain, it stands to reason that the Indian test used a more guaranteed way of controlling yield - a heavy tamper. Looks to me like the case for new testing just went up in a mushroom cloud made by the thermal plume from the N2TN experts' own articles?

[satyarthi]

Since a category N2TN (need to test now) has been introduced. It is fair if we acronymify the other category N2NTA (need to never test again) too.

The 1998 tests were accompanied by a declaration by India that it now considered itself a nuclear power with an intention to maintain a nuclear arsenal towards maintaining a minimum credible deterrent.

That announcement by India of coming out as a nuclear power was quite a big deal. Any new tests will not have that bite. But if the world, rather surprisingly, came around to India's view rather quickly, showing remarkable realism and reasonableness, why can't the same realism and reasonableness expected after a new series of tests?

IMHO it is much easier to "justify" tests by a declared, and effectively accepted, nuclear power, based on need to maintain its arsenal, than to break into that club for the first time.

IMHO predictions about ill effects of new tests have not been justified satisfactorily.

Lets recall, how quickly N Korea was accomodated for its transgressions despite many in the forum expecting it to be severely punished.

Gathering all the precedents (China, Korea, Pakistan etc), and assuming that tests meant for proofing of existing designs by a declared nuclear power can not be as disturbing as the original tests, and expecting the same amount of realism and reasonableness by the world as seen after 1998, IMHO new tests by India will not be as big a deal as it is being presumed by N2NTA people.

It will help if N2NTA people justify their predictions of ill-effects of testing by any existing precedents.

[shiv]

Is this what India would use too, or Botswana, if it had to make a TN bum.

Yes if Botswana wants to usefully deter rather than argue for compassion in understanding its low yield pure fusion TN deterrence.

I suppose Botswana has endless supplies of spent Uranium fuel for using as tamper then? Or does it have access to other materials for tamper, since tamper accounts for a huge percentage of yield (by fission) in a "Thermonuclear" bum?

[enqyoobOLD]

satyarthi: That would b "NR2TA" in James Bond fashion. "No Rush to Test Again".

There was a good reason why the world came around to India's viewpoint in 1998. Pakistani stupidity. Remember the wild celebrations of relief when TSP tested? We would have been far worse off than North Korea today if it weren't for the idiots in Islamagood. What dummies will we find this time? Myanmar junta? Bangladesh?

[satyarthi]

It is true that we celebrated Pakistani stupidity.

But why couldn't the world come down on BOTH India and Pakistan like 200kt of bricks? What was so magical about Pakistani touch? Pakistan had already been slipping in US eyes.

IMHO Pakistan only provided some points to argue about in negotiating circles. But it didn't really change the reality much. And quick turn around of other countries was based on realism regarding India, towards which Pakistani angle counted for little.

I would prefer India to demonstrate even a "Raja bomba", for the simple reason that that kind of demo is very effective piskological deterrent. I don't particularly look forward to Indian cities getting nuked or India nuking other countries' cities with small boosted or tactical but much misery causing weapons. I rather no one use the darned things on us and vice versa. And in that view, demonstrating capabilities for big-badda-booming Raja-Bombas make lot more sense.

P.S. N2TN can also be tweaked to N2TNF ( need to test in near future)

[ShauryaT]

2. Karnad's point seems to be that developing weapons with WgPu will take a lot of time after the FBRs come on line, and "India's escape hatch is shut tight" with this deal.

But did the eventual 123 deal actually "shut the escape hatch"? As I read it, it said nothing about what India can or cannot do in the strategic sector, and the FBRs are in the strategic sector, not in the "full-scope inspection" etc. The only thing that might trigger boycotts, fuel cut-offs etc, is a LIVE (super-critical) test. So this article or its thinking may be dated post-Hyde but pre-123? The Hyde act had all sorts of "recommendations" on poking Unkil's nose and "certifications" etc., none of which appeared in the 123.

N^3: FWIW: Read the word "civilian" in the separation agreement and realise what the game plan is? When FMCT comes into force, the pressure will be to stop all fissile production and get most of India's reactors under safeguards, including breeders. I think, the only thing that India may bargain for is things such as Pu for its ATV fleet and some research.

As far as Hyde clauses not being in 123, tons have been written on it. If I have a contract, which is governed as part of a larger contract, like a work order as part of a master agreement, there is no need to replicate the provisions of the master agreement in the work order.

It is best for India to negotiate with the US government as a whole and not in parts. The US does the exact same thing. It does not say, we are governed only by the 123, it says all American laws will apply. In my view, it is extremely short sighted or even delusional to think that Hyde does not apply et al. It is another matter that we will not allow some provisions of the Hyde to apply no matter what but let us not go to the extent of saying that Hyde does not apply and hence does not matter. Without Hyde, there would be no 123.

I honestly request everyone to end this debate of non applicability of Hyde. 123 is not governed by any international law, in fact it is explicitly prohibited. Even international laws DO NOT get automatic treatment "on par" with US laws, as a recent US supreme court judgment has indicated.

N^3: I know, you do not want a test, because you fear the derailment of the Indian economy and you do not think, it is worth it. I disagree but respect that view. I think, what happens IMO, you tend to get overboard and slam everyone else with your superior argumentative skills and with your killer Pinglish, there is no competition.

[enqyoobOLD]

No (that was no to satyarthi, not shauryaT), the times have changed. Tsar-Bomba may have impressed the world in 1970, but since it can't be done atmospheric, it won't be very impressive anyway. It will just cause anger and contempt.

Same money spent on a space shot is better bang for the buck, far more visible, and will demonstrate accuracy/precision to scare the right people. That's the other reason why I say, sent one to the Sun. Sooryayaan. Equipped with lots of POK sensors, sending data straight to DAE.

ShauryaT:

The 123 is the only way there can be an international agreement with the US, AFAIK. As we have discussed b4, all it takes is for India to pass laws stating India's constraints, and India's signature is governed by those.

Other than that, you say: "If FMCT comes into force". But then India is still a nuclear weapons state, with the strategic program NOT subject to international inspection, so I still don't see the big deal there. Indian mined uranium, and spent/reprocessed fuel from India's strategic-sector reactors, are India's business. The N2TN ppl are basically saying what their equivalents in America say: IOW, to all international agreements.

I don't disagree with that sentiment, but the stategic arguments seen so far do not show why testing will achieve anything that is worth the cost to the civilian economy, and to prospects for technological advancement in all areas.

And you can't escape by saying that it's my "superior argumentative skills" or "Pingreji" that's hindering you - in fact I regard these as unfair and scary tactics, given all the "Rona-Dhona" about "civility" etc. I am not abusive to anyone. yes, , yes, but personal abuse, no.

The fact is that the N2TN and I2T crowd were committing atrocities for weeks b4 I decided to check why I was getting such interesting emails like

"XXXXX, Go F*** Urself!" (one example)

It was pretty clear that not enough discussion was going into the motivations behind the I2T (because the "patriotism" and "jingoness" of the crowd was so much above question). So ppl were arguing about the veins in the leaves, and missing the forest.

The fact is that when we dig deep enough and cut out all the false reasoning, there is nothing left to justify N2TN, and some very uncomfortable realizations come about the motivations behind I2T.

We have also seen the detailed arguments put forward by the inside experts like P.Iyengar and the fringe expert commentators like Karnad. Each makes sense in his narrow frame of argument, but open them all out and shake them out into a heap, and you see that they don't point to testing as the best course (or even a sensible course of any sort) for the national interest.

Let's list the arguments listed:
1. Weapon reliability must be demonstrated again and again for statistical confidence. The successful tests may have been a fluke (actually no one has advanced this, but I will). This one actually makes sense, but I hold that deterrence is effective whether or not the deterrent will actually explode if dropped on the targets, as long as there is no testing to show the precise statistics.

2. 1MT class weapons are needed for deterrence. I disagree, and this is clearly explained by shiv as well. 1 MT class weapons are doomsday weapons, but doomsday can just as well be celebrated with 10KT weapons and those are far more survivable since they can be sent in large numbers, with small delivery vehicles.

3. Also, in our particular context, 15KT to 20KT weapons (or even 1KT) may be far more relevant to stopping genocidal invasions. These are far more scary to the enemy, since these can be used without invoking the final Doomsday option or causing very large collateral damage.

4. S1 did not get past 45KT, and this suggests that the tritium gas was not fully "burned". But it is also seen that the yield was carefully limited to contain the damage, given the proximity of the Rajasthani village. As it stands, the village suffered pretty serious damage (DDM whined about that). This means to me that the yields (and/or their effects) were greater than the designers actually anticipated. So what S1 showed was the ability to control yield in such a boosted-fission weapon, even though burn was very partial. It is also seen that S1 class weapons cannot be scaled to 1MT anyway, (but see (2) and (3) for why this is irrelevant.

5. "1MT is needed for ICBMs". I argue (and no one seems to pick up on that) that an offence based on ICBMs is not credible any more, that it can be completely defeated. OTOH, a strategic offence based on independent, cruise missile delivery systems, is not defeatable by anything I can see in development.

So from all the above, it seems clearly demonstrated that the POK-2 tests achieved the maximum that the planners really intended, and in fact they cut it very fine indeed. This is the perfect place to leave the deterrent and go on to build enough warheads.

The emphasis should shift to developing delivery systems, full speed, because there will be efforts to put "limits" on testing missiles, in the very near future, and cruise missile development will be banned, as being far too "destabilizing". So the window is very limited there, and we don't want to be caught being the bad guys in the MNPT (missile non-proliferation treaty) or the CMTBT. Right now, UQ and France are behind in hypersonics, but that won't last for very long (they have well-advanced projects). When they get there, CMTBT will be rushed through. India has to stay ahead.

The rest of the arguments, like "Show us that the economic damage from testing will be too much" are just not serious things to debate. Not to ppl who grew up in the 1960s and 70s and 80s.

There u go. In plan old Angreji, not superior Pingerji.

[ShauryaT]

Admins: Can we please ask everyone to stop labeling people here into N2TN, etc. This is exactly how the EJ, EB labels came around to be in the nuclear threads earlier. For, folks, who care about this issue no matter, which side you are on, please desist from these labels. TIA.

[satyarthi]

Same money spent on a space shot is better bang for the buck, far more visible, and will demonstrate accuracy/precision to scare the right people. That's the other reason why I say, sent one to the Sun. Sooryayaan. Equipped with lots of POK sensors, sending data straight to DAE.

Could you please elaborate on this a bit as I am not fully clear.

But, yes, in principle, a test deep in space would be something.

P.S. My point about Raja-Bombas was that it is better to succesfully deter a nuclear war than to successfully fight it.

[ShauryaT]

satyarthi: That would b "NR2TA" in James Bond fashion. "No Rush to Test Again".

There was a good reason why the world came around to India's viewpoint in 1998. Pakistani stupidity. Remember the wild celebrations of relief when TSP tested? We would have been far worse off than North Korea today if it weren't for the idiots in Islamagood. What dummies will we find this time? Myanmar junta? Bangladesh?

If so, then it was indeed a failure of Indian foreign policy, in not being able to convince the world of the dangers that India faced with a non proven weaponized arsenal against proven arsenals from multiple neighbors, proliferated with the help of and/or benign neglect of the super powers themselves.

India would have been STUPID to use TSP demonstrations as an excuse to reduce sanctions on us.

[shiv]

It is true that we celebrated Pakistani stupidity.

But why couldn't the world come down on BOTH India and Pakistan like 200kt of bricks? What was so magical about Pakistani touch? Pakistan had already been slipping in US eyes.

IMHO Pakistan only provided some points to argue about in negotiating circles. But it didn't really change the reality much. And quick turn around of other countries was based on realism regarding India, towards which Pakistani angle counted for little.

I would prefer India to demonstrate even a "tsar bomba", for the simple reason that that kind of demo is very effective piskological deterrent. I don't particularly look forward to Indian cities getting nuked or India nuking other countries' cities with small boosted or tactical but much misery causing weapons. I rather no one use the darned things on us and vice versa. And in that view, demonstrating capabilities for big-badda-booming Raja-Bombas make lot more sense.

P.S. N2TN can also be tweaked to N2TNF ( need to test in near future)

Satyarthi Pakistan was in doodoo after rescuing India, but 9-11 rescued Pakistan.

May I make a point about Piskology of Tsar Bomba type yield in the Indian context?

High yield bombs can be used to
1) scare a potential adversary
2) reassure an India that is not confident of itself that they too have long one
3) both

Unfortunately 1 and 2 are not exactly the same. Adversaries may already be scared but we may be hollering to test because we are not confident. In order to boost our own confidence we may be saying "Adversaries are not scared. test now to scare them". In reality we may be asking to test because we are worried. Adversaries who are scared are served well by keeping their anxieties secret and let Indian anxieties pour out into public domain.

Obviously, adversaries know their own mind and they know whether they should be worried or not by India, but they will never reveal their true feelings.

However, by seeing one group of Indians asking for an immediate test "to scare adversaries" the adversary can easily understand one or two things about India and Indians

Seeing Indians holler for a test will immediately tell an adversary that many Indians are not confident of their own deterrence, and that many Indians do not believe their own government, scientific establishment or even armed forces.

This is useful information about the state of mind of Indians for psy ops. Whether the India deterrent is effective or not it means that Indians are already feeling defeated and lack confidence in their arsenal. Their confidence can only come from testing and testing a multimegaton bomb. Once you know that a country has people who are deeply worried about their own strength you can play various games to split opinion in the country and undermine the nation.

It is now possible to play a game that says "Hey we know that the Indian deterrent is useless"

"How do we know it is useless?"

"The Indians themselves are not sure and want to test more."

Once you have this sort of statement coming from adversary nations, they will be provoking India to either test or make a public statement.

If India tests - it will put India in line for military sanctions. If India does not test, they will keep on provoking India and saying 'Nayahaha - your deterrent is a fizzle"

If GoI issues a statement in response - it will mean that GoI is being stung by their criticism enough to make a statement in response, and any statement can be used by an adversary to show the Indian population how the government is still lying and is pretending that testing is not needed. this will be aimed at getting the Indian doubters to force their government to test.

If we test- we get punishment + further mocking that the tests were useless. yields were low' "partial burn" Fissile stocks used up etc

The world is already in the middle of an intense psywar related to nuke testing and we on the forum have fallen prey to that and have actually (and needlessly in my opinion) furthered the cause of a number of anti Indian interests while merely seeking to boost our own confidence.

Luckily BRF is too small and piddly an entity to make a difference. But when we speak of analysis and thinking things through on questions of deterrence and yield - the world that opens up is much larger than we have anticipated on here The piskological game is so big that we are presumptuous and naive to try and break into that without grasping the larger picture.

JMVHO

[enqyoobOLD]

The acronym N2TN stands for "Need to Test Now" or as Satyarthi points out, maybe N2TNF (Need to test in near future). I don't see anything disrespectful, much less abusive, about that. It says nothing about gender, race, religion, region, caste or sexual preference or parentage. If you believe that India needs to conduct live nuclear tests in the near future, why be ashamed of it? If you don't believe in it, why argue for it?

As for the term "Energizer Bunny" it beats the heck out of the more descriptive terms for the sort of behavior that brought about that description. It was first brought in as a gentle way of describing people who were arguing that the mass murder of Indian citizens in an Indian state by crazed mobs was "justified as the reaction of angry people". And who would keep arguing that incendiary and destructive line despite all sane advice. It was used to describe people who would simply not be honest in debating. When they lost on reason, they would whine that the side of reason was "argumentative" (helllooooo! That's what debate is about, thinking up good solid reasons!) and then they would keep repeating the same discredited points in total disregard.

So, shauryaji, please continue to debate using logic and reason. If the truth is on your side, you should prevail. Otherwise, maybe you should accept the truth. Cheers

[ramdas]

N^3,

S-1 was a two stage thermonuclear device with a boosted fission primary. Not a boosted fission device.

Why do you feel we would have been worse off than North Korea had TSP not tested in 1998 ? The sanctions on both were the same. We saw that it had very little effect on us in the end. Had the same "never test again" argument been in force then, POK II would never have happened. My feeling is that if we test, the "international community" will make some noises and then reconcile itself to the reality.