Deterrence

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shiv
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Re: Deterrence

Post by shiv »

ShauryaT wrote:
disha wrote:^^ Where are you getting your numbers from? How are you calculating that a BF will require 750 Kg of weight and how are you calculating non-BF weight? Is it 200 Kg? 300 Kg? 700 Kg?
From here, there are other sources too for these calculations, including BRF archives.
Here is a useful graph
A 1000 kg device will need a max diameter of about 40 -50 cm
A 2000 kg device will need a max diameter of just over 50-60 cm

Why do we make 1 or 2 meter diameter missiles with 1000-2000 kg payloads?

Image
shiv
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Re: Deterrence

Post by shiv »

The last 5 nuclear tests conducted by France in 1995 (after the last tests in 1974) - supposedly Thermonuclear weapons
  • Sep 5 1995 Tests resume Moruroa
    Sea Goddess (20kt)

    Oct 2 1995 < 150 kt Fangataufa

    Oct 28 1995 approx 60 kt Moruroa

    Nov 23 1995 approx 60-80 kt Moruroa

    Dec 28 1995 30kt Moruroa
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Re: Deterrence

Post by sudeepj »

Shiv, read this position paper from the first page to the last. Its one of the single most informative I have come across. Without it, we are having a bit of GIGO.

https://cryptome.org/2014/06/wmd-4th-gen-quest.pdf

Radition Implosion means teller ulam. There is no other known physics to extract fusion energy out of atoms. At the end of the day, the game is all about extracting energy from cheap materials. So if you can get a lot of bang from U238 tamper around a fusion secondary, very much the better! If you can use Li instead of Tritium for the fusion secondary, very much the better! and so on.

According to the authors, a Mega Tonne TU design is not particularly challenging, which is why even powers with primitive technology such as then China, were able to get 'there' relatively soon (only their 6th test), but a low yield TU design is much more challenging, which is what Indians have tried.

Further, its much more economical to use 100-300KT weapons than MT weapons that waste much of their energy into space. Which is why you see almost all powers using strategic warheads in this range.

The most important question is, did we manage to get some kind of a thermo nuclear burn going in the secondary.. approx 46KT sounds about right for a thermonuclear bomb with an inert lead tamper around the fusion secondary. But there are all kinds of claims and counter claims about the yield, and people like Santanam are not convinced with the yield value.

At this point, its an open question. It certainly appears that the tested device was very ambitious. Its also clear, at least to me, that Indian scientists can design and provide a deliverable MT range device if it is so desired. Everything else, its a guesswork.
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Re: Deterrence

Post by shiv »

sudeepj wrote:Shiv, read this position paper from the first page to the last. Its one of the single most informative I have come across. Without it, we are having a bit of GIGO.

https://cryptome.org/2014/06/wmd-4th-gen-quest.pdf

Radition Implosion means teller ulam.
No saar, Radiation implosion means compression by radiation, of which Teller Ulam is one method - probably the easiest and requiring the least sophistication.

You have posted the Gsponer pdf which I have had in my archives for years - though now unread for about as long.

See page 19 and a footnote number 35 . Teller Ulam is one of the designs and the design that is discussed but before that: - screen grabs from the pdf below. Note that Edward Teller himself wrote in 1987 that other methods were possible. The same paper has something to say about the 1998 Indian tests on page 23

However, after considerable theoretical work, it was realized in 1950 in the
United States (and in 1954 in the Soviet Union) that ignition and longitudinal
propagation of a thermonuclear detonation in a cylinder of liquid deuterium was
very difficult, if not impossible.35 Consequently, other possibilities were given a
fresh look. These included ideas derived from concepts that had been successfully
tested in the meantime, such as “boosting,” or Andrei Sakharov’s “layer-cake.”
We will not try to describe these attempts or go into the details of their history.36
Instead, we will examine the conditions under which uniform ignition and burn of
a device containing on the order of 10 to 100 kg of thermonuclear fuel is possible.
35
In the 1970s, however, the feasibility of this concept was demonstrated in detailed computer
simulation; only experimental complexity prevented its full-scale demonstration [11]. Referring
to a “number of alternative designs (that) were considered and rejected as technically doubtful or
infeasible prior to the success of the hydrogen bomb,” Edward Teller stated in 1987 that, “since
that time, further research proved all of these possibilities feasible,
though not preferable to the
actual solution” [87, p.726].
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Re: Deterrence

Post by shiv »

sudeepj wrote:
The most important question is, did we manage to get some kind of a thermo nuclear burn going in the secondary.. approx 46KT sounds about right for a thermonuclear bomb with an inert lead tamper around the fusion secondary. But there are all kinds of claims and counter claims about the yield, and people like Santanam are not convinced with the yield value.

At this point, its an open question. It certainly appears that the tested device was very ambitious. Its also clear, at least to me, that Indian scientists can design and provide a deliverable MT range device if it is so desired. Everything else, its a guesswork.
From the pdf you posted - page 23
On 17 May 1998, Indian officials claimed that one of
the devices detonated on 11 May was a two-stage hydrogen bomb with a yield of
about 45 kt.39 Since a relatively low-yield H-bomb is more difficult to make than
a high-yield one, this test means that India was capable to detonate a sophisticated
thermonuclear device 24 years after it made its only previous nuclear test — a 12
kt fission bomb [65].
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Re: Deterrence

Post by shiv »

One more quote from the pdf posted - a double whammy where
1. the "hydrogen bomb" is_not_defined as == Teller Ulam as is being suggested on BRF, and
2. Why further testing is useless and everyone has accepted that there is no point testing further

Page 105
Second generation nuclear weapons are fusion-boosted fission-explosives
(“boosted atomic bombs”) and two-stage thermonuclear devices (“hydrogen bom-
bs”). In hydrogen bombs, a tritium-boosted atomic bomb is used to implode and
ignite a secondary system in which fusion reactions produce most of the yield. The
development of these weapons required extensive testing and resulted in high-yield
(100–500 kt) weapons with yield-to-weight ratios about twenty times larger than
those of the best first generation nuclear weapons. Progress on these weapons has
been slow, and the scientific understanding of the details of the secondary system
is still incomplete. 3 Nevertheless, after more than 50 years of research and de-
velopment, and after almost two thousand test explosions, no significant progress
is expected for this generation of weapons. The continuation of full-scale testing
would probably never have changed this situation, given the great number of com-
plex phenomena that occur simultaneously within the fraction of a microsecond
of the explosion of an H bomb. This is possibly the main technical reason why the
comprehensive test ban treaty (CTBT) is, in fact, militarily acceptable.
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Re: Deterrence

Post by shiv »

I need to thank SudeepJ for reminding me of this paper - re reading throws up so many gems.
First - about the Chinese nuclear tests - from page 23
Moreover, the Chinese were able to detonate their first full-yield hydrogen bomb
after only three fission bomb tests, one boosted-fission test, and one preliminary
two-stage hydrogen bomb principle test [26].
This demonstrates that a rather prim-
But a page 10 footnote has details of the same third Chinese test - which is a variation of radiation compression and NOT a classic Teller Ulam.
However, a small amount of 6 LiD at the center of a 10–30 kt fission bomb can increase its
yield to 100–300 kt. This was done, for example, in the third Chinese nuclear explosion [26].
Last edited by shiv on 11 Feb 2017 22:45, edited 1 time in total.
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Re: Deterrence

Post by shiv »

Another gem from page 17
testing.
• When actually exploding an experimental boosted device for testing purposes,
there are several advantages in keeping the yield as low as possible. This enables:
(1) to insure that the technique of using an implosion device that would be a fission-
fizzle without tritium gives the calculated yield with only a minimum amount of
tritium in the pit, (2) to enhance the contribution of the delicate initial fission-
fusion phase relative to the final fusion-fission phase which is a simple nuclear
amplification process, (3) to minimize the background signals which may overload
the measuring instrumentation, (4) to be able to explode the device at a relatively
low depth into the ground and to minimize the damage to the test range and its
vicinities, and, finally, (5) to waste as little precious tritium as possible. This
explains why most of the tests performed par India and Pakistan in May 1998 were
of very low yield, i.e., of only a fraction of a kiloton.
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Re: Deterrence

Post by shiv »

:rotfl: How did I miss this?
• Boosting can also be used to make efficient and reliable fission weapons
in which reactor grade plutonium is used instead of weapons grade plutonium.
The reason is that — with boosting — the problem of the preinitiation of the
chain reaction, which creates difficulties in making a non-boosted fission bomb
[66, 69], is no longer a serious problem. As was explained above, even if the chain
reaction starts at the worst possible time, the temperature that can be reached in
the fissile material is easily sufficient to ignite the DT mixture.30 The preference
for weapons-grade plutonium is therefore mainly a matter of convenience (e.g.,
to simplify the design because reactor-grade plutonium may require some kind of
cooling to evacuate the 240 P u decay-heat) and a way to produce warheads that can
be kept in storage or on alert for relatively long periods of time before recycling.
Moreover, independently of the type of fissile material used, the construction of
“simple” and “deliverable” tritium-boosted nuclear weapons can be easier than
the construction of primitive Hiroshima or Nagasaki type atomic bombs: the main
problem is to acquire the few grams of tritium that are needed for every weapon.
Two of the five devices tested by India in May 1998 are believed to have used
plutonium that was not classified as weapons grade
[54].
No I don't think our nuclear scientists were morons or liars. Everything they said fits in with this publication. We need to kick ourselves in the backside a thousand times.
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Re: Deterrence

Post by sudeepj »

shiv wrote::rotfl: How did I miss this?
• Boosting can also be used to make efficient and reliable fission weapons
in which reactor grade plutonium is used instead of weapons grade plutonium.
...[/b] [54].
No I don't think our nuclear scientists were morons or liars. Everything they said fits in with this publication. We need to kick ourselves in the backside a thousand times.
Exactly. If you read on, he goes on to describe the latest generation of radiation implosion weapons, that do not rely on a heavy tamper or a 'spark plug', instead on a "thermonuclear detonation wave" triggered by a radiation implosion. This is the type of weapon light enough for MIRVing 10 to a missile. I speculate, that this is the type of weapon that they tried which led to all kinds of doubts. I base the speculation on RChidambaram repeatedly thumping the table with 'these are the latest vintage in weapon design, we are ahead of the older designs available with other powers'.

As for TU or not, my understanding is, anything that is two stage using a radiation implosion is TU. Anything that is just one stage relying on chemical explosives for initiation is a fission or a boosted fission design.
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Re: Deterrence

Post by Amber G. »

sudeepj wrote:
Radition Implosion means teller ulam. There is no other known physics to extract fusion energy out of atoms. .....
>>>" There is no other known physics to extract fusion energy out of atoms ...
REALLY!!!!
Sun, one of the well known example produces energy out of Fusion... even before Teller-Ulam were born!

Speaking as a physicist, this above type of claim is really nonsense.
(For scientists, "Radiation implosion" just means " \the compression of a target by the use of high levels of electromagnetic radiation")
For those who are interested in physics: Some more basic well known facts (these are not classified so it can be checked by reputable sources - for more details ask your physics professor etc..)

- Radiation implosion was first developed by Klaus Fuchs and John von Neumann and a patent (then secret) was filed in ..ohh 1946 (I just checked the year)

(Piece of trivia - This design, we now know was given to the USSR by Fuchs as part of the notorious nuclear espionage - From what I know USSR did not use it for fission weapons)

-1951: Stanislaw Ulam: Use hydrodynamic shock of a fission weapon to compress more fissionable material very high density to make two-stage fission bombs (Megaton Range).

- 1951: Edward Teller (who was obviously familiar with Neumann & Fuchs work) radiation compression would be both faster and more efficient than hydrodynamic shock. This became what is known as the "Teller–Ulam design" for the hydrogen bomb. ( x-ray pulses lasting just a micro-second or so from primary can deliver energy output in 10^14 joules range - strong enough for fusion trigger)

(No this design is by no means unique. Many think that Chines design for radiation implosion was a little different -- using lenses instead of x-ray mirrors -- but I digress)

- Many people think that radiation implosion is pressure caused by x-rays. That is, of course, true but in most/many cases the pressure created by vaporized materials is much larger This is the recoil from outer surface of inner core which becomes so hot that it vaporizes and flies in all direction with high velocity. The "radiation implosion" in these hydrogen bombs ought to be called "radiation ablation implosion."

- Many of the terms (like "x-ray" reflectors etc) used in popular media / wiki / even in BRF/ is, to put it mildly, misleading. They are interpreted by many in funny way (different than what a physicist will mean)

- The details/designs is still HIGHLY classified and many times even the most "facts" cited authoritatively by critics are non-sense.

Disclaimer: I am not a weapons expert but just a physicist.
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Re: Deterrence

Post by Amber G. »

Shivji (and others) - you may enjoy the Mueller's class video I posted, if you have not seen it. It is about a hour long video but contains lot of good material.

This is from one of the most popular physics course: "Physics for future Presidents". Mueller is highly respected Physics professor. (His thesis adviser Von Neumann's was the one who thought of and designed the explosive lenses needed to compress for the first Pu Bomb, and worked with Teller and Ulam for nuclear physics/math involved in thermonuclear bomb.
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Re: Deterrence

Post by Amber G. »

Can someone confirm/contradict this
I heard that Dr. Samar Mubarakmand (as opposite to Xerox Khan) said/asserted/believed that S1 was a successful thermonuclear test.
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Re: Deterrence

Post by sudeepj »

Amber G. wrote:
sudeepj wrote:
Radition Implosion means teller ulam. There is no other known physics to extract fusion energy out of atoms. .....
>>>" There is no other known physics to extract fusion energy out of atoms ...
REALLY!!!!
Sun, one of the well known example produces energy out of Fusion... even before Teller-Ulam were born!
You got me there.. I was talking in the context of thermonuclear weapons only and then ignoring the case of the boosted fission type devices. Perhaps I should also add a 'that I know of in the end'.

Please correct me if I am wrong, but isnt staged radiation implosion the only known way of getting a sizeable amount (kg quantities, not grams) of fusion happen in a thermonuclear weapon? And doesnt a radiation implosion mean a TU type design? The key TU ideas being, separating the primary and secondary enough so that the radiation has the time to compress the secondary before disintegration of the device, and encasing the primary and secondary in a hohlraum?
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Re: Deterrence

Post by RoyG »

Amber G. wrote:Shivji (and others) - you may enjoy the Mueller's class video I posted, if you have not seen it. It is about a hour long video but contains lot of good material.

This is from one of the most popular physics course: "Physics for future Presidents". Mueller is highly respected Physics professor. (His thesis adviser Von Neumann's was the one who thought of and designed the explosive lenses needed to compress for the first Pu Bomb, and worked with Teller and Ulam for nuclear physics/math involved in thermonuclear bomb.
I've watched the videos. Thanks for the post.

I don't think there is anything revolutionary about the FBF designs that we tested or the layer cake design. All/most of the world powers have carried out enough detonations, simulations, sub critical testing, LiF etc. to perfect the implosion design. I'm sure our design ranks among the best as well.

Kakodkar and I believe even RC are quoted as saying that a two stage TN was tested. I'm not sure where the confusion is coming.
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Re: Deterrence

Post by kit »

shiv wrote::rotfl: How did I miss this?
• Boosting can also be used to make efficient and reliable fission weapons
in which reactor grade plutonium is used instead of weapons grade plutonium.
The reason is that — with boosting — the problem of the preinitiation of the
chain reaction, which creates difficulties in making a non-boosted fission bomb
[66, 69], is no longer a serious problem. As was explained above, even if the chain
reaction starts at the worst possible time, the temperature that can be reached in
the fissile material is easily sufficient to ignite the DT mixture.30 The preference
for weapons-grade plutonium is therefore mainly a matter of convenience (e.g.,
to simplify the design because reactor-grade plutonium may require some kind of
cooling to evacuate the 240 P u decay-heat) and a way to produce warheads that can
be kept in storage or on alert for relatively long periods of time before recycling.
Moreover, independently of the type of fissile material used, the construction of
“simple” and “deliverable” tritium-boosted nuclear weapons can be easier than
the construction of primitive Hiroshima or Nagasaki type atomic bombs: the main
problem is to acquire the few grams of tritium that are needed for every weapon.
Two of the five devices tested by India in May 1998 are believed to have used
plutonium that was not classified as weapons grade
[54].
No I don't think our nuclear scientists were morons or liars. Everything they said fits in with this publication. We need to kick ourselves in the backside a thousand times.
:mrgreen: :mrgreen: .. no wonder pakis have gone on record saying India has nearly 500 nukes in its arsenal :((
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Re: Deterrence

Post by shiv »

Amber G. wrote:
- Many people think that radiation implosion is pressure caused by x-rays. That is, of course, true but in most/many cases the pressure created by vaporized materials is much larger This is the recoil from outer surface of inner core which becomes so hot that it vaporizes and flies in all direction with high velocity. The "radiation implosion" in these hydrogen bombs ought to be called "radiation ablation implosion."
Yes in fact this is what the Gsponer pdf also says
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 the tamper inwards, imploding the fusion fuelvery high densities
i will watch that video - I recall you had posted it but somehow I think I lost the link or forgot
Last edited by shiv on 12 Feb 2017 07:52, edited 1 time in total.
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Re: Deterrence

Post by shiv »

sudeepj wrote: Perhaps I should also add a 'that I know of in the end'.

Please correct me if I am wrong, but isnt staged radiation implosion the only known way of getting a sizeable amount (kg quantities, not grams) of fusion happen in a thermonuclear weapon? And doesnt a radiation implosion mean a TU type design? The key TU ideas being, separating the primary and secondary enough so that the radiation has the time to compress the secondary before disintegration of the device, and encasing the primary and secondary in a hohlraum?
Teller Ulam is the only one that has been declassified and explained. The Gsponer pdf refers to others that were declared feasible many years after the Teller Ulam design was tested. The Teller Ulam design is one possible design - not the one and only design

As per the quote from the pdf you posted it is more difficult to get a small bang. Not a fizzle. Teller Ulam is good for big bangs.

"Thermonuclear weapons" as per a US declassification document says:
https://fas.org/sgp/othergov/doe/rdd-7.html#I49
  • d. The fact that in thermonuclear (TN) weapons, a fission "primary" is used to trigger a TN reaction in thermonuclear fuel referred to as a "secondary". (72-11)

    e. The fact that, in thermonuclear weapons, radiation from a fission explosive can be contained and used to transfer energy to compress and ignite a physically separate component containing thermonuclear fuel. (79-2)

    Note: Any elaboration of this statement will be classified.


    f. Fact that fissile and/or fissionable materials are present in some secondaries, material unidentified, location unspecified, use unspecified, and weapons undesignated. (91-1)
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Re: Deterrence

Post by shiv »

Turns out that the Gsponer pdf I have is from 2008 and not the 2009 one posted by sudeep. The earlier one has some common passages. Here is one passage from page 27 that I did not find in the newer one
This is why the pusher/tamper is sometimes called the “third-stage” of a
thermonuclear weapon. For example, assuming as in Fig.4 that the yield is 150kt
if the pusher/tamper is made of U 238 , the yield will be 300kt if the pusher/tamper is
made of U 235 . On the other hand, if the pusher/tamper is made of a lead or bismuth,
the yield will be significantly lower, on the order of 50kt. This is most probably
what the Indian scientists have done in 1998 in order to be able to detonate the
device at a relatively low depth into the ground, and to minimize the background
signals which may overload the measuring instrumentation.
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Re: Deterrence

Post by sudeepj »

shiv wrote:
sudeepj wrote: Perhaps I should also add a 'that I know of in the end'.

Please correct me if I am wrong, but isnt staged radiation implosion the only known way of getting a sizeable amount (kg quantities, not grams) of fusion happen in a thermonuclear weapon? And doesnt a radiation implosion mean a TU type design? The key TU ideas being, separating the primary and secondary enough so that the radiation has the time to compress the secondary before disintegration of the device, and encasing the primary and secondary in a hohlraum?
Teller Ulam is the only one that has been declassified and explained. The Gsponer pdf refers to others that were declared feasible many years after the Teller Ulam design was tested. The Teller Ulam design is one possible design - not the one and only design

As per the quote from the pdf you posted it is more difficult to get a small bang. Not a fizzle. Teller Ulam is good for big bangs.

"Thermonuclear weapons" as per a US declassification document says:
https://fas.org/sgp/othergov/doe/rdd-7.html#I49
  • d. The fact that in thermonuclear (TN) weapons, a fission "primary" is used to trigger a TN reaction in thermonuclear fuel referred to as a "secondary". (72-11)

    e. The fact that, in thermonuclear weapons, radiation from a fission explosive can be contained and used to transfer energy to compress and ignite a physically separate component containing thermonuclear fuel. (79-2)

    Note: Any elaboration of this statement will be classified.


    f. Fact that fissile and/or fissionable materials are present in some secondaries, material unidentified, location unspecified, use unspecified, and weapons undesignated. (91-1)
Radiation implosion is the only known technique. Its possible there are others..

I doubt Indian designs are based on others. Listen to some RC and Kakodkar interviews where they describe the high level design. They have mentioned 'staged', which means TU.

What the document says is, TU is relatively easy to do if you want a big bang, but more difficult to reduce the yield to 100KT type of levels.
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Re: Deterrence

Post by sudeepj »

shiv wrote:Turns out that the Gsponer pdf I have is from 2008 and not the 2009 one posted by sudeep. The earlier one has some common passages. Here is one passage from page 27 that I did not find in the newer one
This is why the pusher/tamper is sometimes called the “third-stage” of a
thermonuclear weapon. For example, assuming as in Fig.4 that the yield is 150kt
if the pusher/tamper is made of U 238 , the yield will be 300kt if the pusher/tamper is
made of U 235 . On the other hand, if the pusher/tamper is made of a lead or bismuth,
the yield will be significantly lower, on the order of 50kt. This is most probably
what the Indian scientists have done in 1998 in order to be able to detonate the
device at a relatively low depth into the ground, and to minimize the background
signals which may overload the measuring instrumentation.

Makes sense!
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Re: Deterrence

Post by prasannasimha »

^ Also the yield was deliberately decreased as the closest village of Khetolai near the test site would have got severely damaged if the yield was higher. This was evacuated at the time of the test but while the world did not knopw of the test the villagers guessed it right !

https://www.google.co.in/maps/place/Pok ... 71.9165463
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Re: Deterrence

Post by shiv »

sudeepj wrote: I doubt Indian designs are based on others. Listen to some RC and Kakodkar interviews where they describe the high level design. They have mentioned 'staged', which means TU.
This is an assumption from which we open the door that led to the slippery slope that led to our nuclear scientists being called incompetent bums and liars on this forum

The Gsponer pdf that you have posted also says that Teller Ulam is the easiest and most elegant way to get a huge bang. And because people thought "hydrogen bomb" or "secondary by radiation compression" was definitely a Teller Ulam people wanted a BIG megaton bang and the puny 30-40 kt did not cut it. So "the bomb fizzled", the scientists were bluffing the nation was deceived based on an assumption.

There is some technical GIGO here. Teller Ulam is a specific design that is not just a separate secondary (an idea that was independently discovered by Sakharov and friends) but has 2 more important aspects - i.e a heavy fissionable tamper and a spark plug (Teller's idea)

Modern thermonuclear weapons can do away with the heavy fissionable tamper and the spark plug ( a so called "Wheeler-mode" design) - and the Indian test was probably the latter.
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Re: Deterrence

Post by shiv »

From 2003
http://www.indiadefence.com/nuc_status.htm
The DRDO had provided the chemical explosion technology and the bomb casing and deployment trials, and is the closest to the operations. The other details of D-T Neutron Beam Generators, explosive lenses, lithium 6 Deuteride, PU 239, U-235 and gas spark plugs have never been shared.
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Re: Deterrence

Post by sudeepj »

In my mind, I am simplistically calling any staged weapon using radiation implosion as a TU type design. As far as I am concerned, there is no slippery slope and calling scientists names without concrete evidence of fraud, when ones own scientific capability is restricted to the very basic minimum is just not done.

*Sakharov's third idea is also a TU type design. Why not Sakharov's design? Dont ask me. I dont name these things.
The Gsponer pdf that you have posted also says that Teller Ulam is the easiest and most elegant way to get a huge bang. And because people thought "hydrogen bomb" or "secondary by radiation compression" was definitely a Teller Ulam people wanted a BIG megaton bang and the puny 30-40 kt did not cut it. So "the bomb fizzled", the scientists were bluffing the nation was deceived based on an assumption.
If you think about it clearly, given the constraints as in the GSponer paper, the Indian bomb team *had* to choose this path. Why?

1. They had one chance to test, with the next being in the realm of unknown.
2. The most difficult part of the weapon is getting the D-T and D-D reaction going in the secondary. Once that happens, the majority of the explosive power comes from the fission of either U238 or the enriched U235 tamper.
3. They would want to characterize the fusion very carefully. The extra energy from the tamper could have damaged the instrumentation, test range or just muddied up the results. With a large fraction of the energy expected from the fusion, this mode gave them the cleanest experimental setup.
4. Pak and Chinese scientists, those who need to know, do know all of this physics. So there is no need to thump chests and claim all kinds of things and demonstrate a huge explosion. If we are ever threatened, we will test again, and at full yield.

btw. work on implosion systems never stopped.. Just look at the awards to scientists.
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Re: Deterrence

Post by ramana »

Been away for a few weeks.

Why are we hashing 3 to 4 pages again?

Shiv in five sentences what's your point?
ShauryaT, same.
KS garu in email said we don't need to test but should not give up the right to test.

Yes there is a deep state in India. Its called Sarkar.
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Re: Deterrence

Post by shiv »

ramana wrote:Been away for a few weeks.

Why are we hashing 3 to 4 pages again?

Shiv in five sentences what's your point?
ShauryaT, same.
KS garu in email said we don't need to test but should not give up the right to test.

Yes there is a deep state in India. Its called Sarkar.
er ramana please don't disappear and ask things like "what's your point." This is a forum. If you are off for weeks and are not bothered about reading what was discussed please don't make dictatorial demands. I think that is an insulting question when I have taken the trouble to read and quote things that were not quoted earlier.
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Re: Deterrence

Post by nirav »

ramana wrote:Been away for a few weeks.

Why are we hashing 3 to 4 pages again?

Shiv in five sentences what's your point?
ShauryaT, same.
KS garu in email said we don't need to test but should not give up the right to test.

Yes there is a deep state in India. Its called Sarkar.
It's a cycle..
One every season someone repeats the same - our bomb was fizzle, need to test asap, deterrence is in doubt..
It's countered by people who do not think so.

3-4 pages worth of hashing is actually quite less considering the copious amounts expended earlier.

Anyway one can only present points of view.
You Saar have seen the light @ deterrence "issue"..
Many haven't, and I'm afraid till everyone sees it, these hashings will continue..
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Re: Deterrence

Post by shiv »

nirav wrote:
It's a cycle..
One every season someone repeats the same - our bomb was fizzle, need to test asap, deterrence is in doubt..
It's countered by people who do not think so.

3-4 pages worth of hashing is actually quite less considering the copious amounts expended earlier.
Well said. New people join the forum all the time and the same old issues come up - but new information comes out. I discovered that the Gsponer paper posted by sudeepj from 2009 was not the same as the 2008 paper I had by the same authors and taking the 2 together gives a lot of insights although much is common between the two.

Particularly revealing to me was the fact that reactor grade Pu bombs can be made to "behave" against pre-detonation by the use of boosting.

Another statement that blew me away was that there seems to be acknowledgement among nations that have done thousands of tests that more and more testing will still not help them understand or predict certain complex processes and that may be one reason why everyone has agreed not to test any more. Working bombs are getting as good and reliable as they can get and there is a gradual move away from massive yields - particularly as old warheads are retired.

A lot of things have moved on in 19 years. We too need to discuss and share new information and not be stuck in the same old rut repeating the same things that were said 19 years ago as you have rightly pointed out has happened.
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Re: Deterrence

Post by nirav »

+1
I lurked through most of the discussion, it was quite informative and a value add..
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Re: Deterrence

Post by Amber G. »

shiv wrote: No I don't think our nuclear scientists were morons or liars. Everything they said fits in with this publication. We need to kick ourselves in the backside a thousand times.
Thanks for this. Let me add:

I may be partial (learning a lot, including nuclear physics from these guys) but don't think they are morons or liars. Far from it. Many of these scientists have been known to people like me and other scientists and they may be modest but they are very capable and have a very high integrity. India has very high critical mass of nuclear physicist and it is unlikely that "bluffing" will work in the long run among them.

OTOH at least some "skeptics" show their utter ignorance for even the most elementary physics principles. So they have very low credibility as far as I am concerned. But they have a large faithful followers.

Yet DDM's (and even some here in brf) do = =. Disappointing.
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Re: Deterrence

Post by Amber G. »

shiv wrote:

i will watch that video - I recall you had posted it but somehow I think I lost the link or forgot
The link was posted just recently here:
https://www.youtube.com/watch?v=5BHdsjo-NR4[/quote]
Other ( + - of that class lectures) can be seen in related links etc..
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Re: Deterrence

Post by Amber G. »

shiv wrote:
Amber G. wrote:
- Many people think that radiation implosion is pressure caused by x-rays. That is, of course, true but in most/many cases the pressure created by vaporized materials is much larger This is the recoil from outer surface of inner core which becomes so hot that it vaporizes and flies in all direction with high velocity. The "radiation implosion" in these hydrogen bombs ought to be called "radiation ablation implosion."
Yes in fact this is what the Gsponer pdf also says
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 the tamper inwards, imploding the fusion fuelvery high densities
i will watch that video - I recall you had posted it but somehow I think I lost the link or forgot
Just to add - my point was that there is MUCH more in designs (which obviously remains highly classified so even those who know can refute silly arguments coming from others) then simplistic views one finds in some -even authentic sounding- sources)

For example, the ablation pressure (caused by recoil of outer surface) if designed right, could be 10X more than radiation pressure alone .. (If my understanding/guesses/calculations/reading etc is correct).

And it is not just ablation only -- possibly type of foam used (when it expands it can also add quite a bit to pressure), lenses/mirrors/geometry and who (except our scientists know) knows what, are quite important and it is unlikely that *details* of lot of what is done is out in open source..

Not saying what is used in S1 - (Don't know, and those who know are not going to give details anytime soon) but assuming that one particular design is like a law is not correct.

What is beyond doubt that these devices worked, and those who matter, has enough confidence in their reliability.
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Re: Deterrence

Post by Rakesh »

India is making Thermonuclear Hydrogen Bombs in Secret Nuclear Facility
http://www.defencenews.in/article.aspx?id=250403

Pakistan express serious concern over India building a Secret Nuclear City
http://www.defencenews.in/article.aspx?id=250382

Pakistan's 'secret nuke city' contention figment of imagination: India
http://economictimes.indiatimes.com/art ... 066492.cms
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Re: Deterrence

Post by ramana »

1) IAF accepts the S-2 bomb even before the tests in 1998.
2) IA and IN accept the large yield weapons which are deployed on Agnis, Prithvis and Dhanush
3) IN is on deterrent patrol with INS Arihant with K-15 and K-4s.

So whats the issue here?

Posting from pdfs is like searching for black cat in dark room which might not even be there.

those who use them trust them.

No one is insulting anyone.

I asked in five lines it shows understanding.


i did in 3 lines above.
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Re: Deterrence

Post by Rakesh »

Clampdown on unauthorised access to nuclear material: India's message to Pakistan
http://economictimes.indiatimes.com/art ... 043793.cms

Nuclear terrorism an international threat, need for global response: Foreign Secretary Jaishankar
http://economictimes.indiatimes.com/art ... 038761.cms
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Re: Deterrence

Post by nirav »

ramana wrote:

i did in 3 lines above.
Saar,
It only highlights that you shouldn't take a break from posting :mrgreen:
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Re: Deterrence

Post by ShauryaT »

Let me put my few lines to state my point.

1. There is credible doubt that the tested S1 device, a scalable yield two stage TN device failed to perform to its designed test yield
2. There are credible indications (by people in the know) that the deployed warhead on our missiles are actually FBF weapons limited by weight/yield. The same inhibitors affect air deployed weapons too in carrying a capable yield.
3. The above limits the efficacy, type and credibility of the deployed arsenal thereby impacting deterrence - based on power and capabilities the nation can wield
4. Given the above, the nation should resume its testing so that the right type of weapons deemed essential for credible deterrence is in place

To your short point that our forces accept it. Two related points, they are not given a choice and when they bring up these issues, the political decision masters have always sided with the the "scientists", providing the military very little if any say in the weapons design, excepting for the Indian Navy, that has somewhat invested in building up a working knowledge of nuclear weapons. e.g: There is no committed nuclear cadre in the armed forces. Moving into and out of SFC is a three year rotation.

We have indeed prosecuted much of the above points back and forth. The recent talk at FINS India as reported by Bharat Karnad, simply reiterates and confirms the same fundamental issue that the scientists claim that the tested design has succeeded and furthermore they can design new weapons based on the tests using simulation and lab tests alone.
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Re: Deterrence

Post by krishna_krishna »

Ramana guru, the one who cannot be named said on this forum many moons ago:

We need to test for two reasons one our TNW designed wasn't proved in proving it's worth/is not scalable.

Secondly our Wheads are not Pu especially in mizzilesthat will have big impact on our submarine crews well being that are supposed to be in contact for longer something western navies learned and moved to complete PU.

I wanted to bring this in discussion as well if gurus can throw light on these two.
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Re: Deterrence

Post by shiv »

ramana wrote:
I asked in five lines it shows understanding.


i did in 3 lines above.
ramana there is an assumption here that everyone must display your level of intelligence, your prodigious memory and your ability to encapsulate in a few syllables that others need to write books about. Like showing understanding by telling Ramayana in 5 lines. It can be done by our brightest. But please don't demand the same intellectual capacity from everyone else. Those of us who don't have it simply don't have it.
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