Pokhran II not fully successful: Scientist - Part-3

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Kanson
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by Kanson »

Amber G. wrote: - Liars (multiple times)
- Snake oil sellers (Wonder if those 'sacrificial xray sensors' will find out 400% which snake oil was there)
- [Men who] Walk on Water (That's why AK is some times known as MWWOW)
- Traitors
-Vapor ware sellers...
.........
but just wanted to set the record straignt.
I just hoped Arun_S will retract his statement when the whole drama got completed.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by negi »

I am merely seeking clarification on
Without the boosting gas, even if the explosives go off, the bum does not go boom (there is not enough fissile material to achieve criticality).
I think since we are using nuclear jargon its definition remains unchanged and some thing which is universally agreed upon.

So I assume critical in the post was pointing to "k=f-l" where k has to be at least '1' for a nuclear reaction to be qualified as critical (which is one of the pre requisites for a chain reaction).

In a nuke it is obvious that the primary fissionable mass (U-235 or Pu) would at least attain critical mass after CE's go off (if not super critical) and this is true for all the designs (FBF,vanilla fission or even a TN).
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by Austin »

Kanson wrote:
Amber G. wrote: - Liars (multiple times)
- Snake oil sellers (Wonder if those 'sacrificial xray sensors' will find out 400% which snake oil was there)
- [Men who] Walk on Water (That's why AK is some times known as MWWOW)
- Traitors
-Vapor ware sellers...
.........
but just wanted to set the record straignt.
I just hoped Arun_S will retract his statement when the whole drama got completed.
Minus the semantics , what if Arun_S said turns to be true ?
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by shiv »

negi wrote: This is a very simplistic statement. There will be a chain reaction else how will boosting initialise in the first place ? However how much % of the Pu will undergo fission will vary (i.e. come down in case boosting does not take place) but it will be critical none the less.All in all efficiency will come down.

Negi I am not an expert but here is a link that might help. It defines a fizzle yield - which occurs when fission actually occurs but a sufficient number of neutrons are not produced to sustain a chain reaction.

http://belfercenter.ksg.harvard.edu/fil ... 07_Hui.pdf
If the nuclear chain is not sustained long enough to cause an explosion, a fizzle will occur. This can happen, for example, if the detonators do not explode at the right time or if the neutron initiator is misfired.9
The smallest possible yield resulting from preinitiation has been referred to as the "fizzle yield.” Some scientists have provided the definition of a fizzle yield. For example, nuclear expert J. Carson Mark provided a criterion for predetonation that the chain-reaction be initiated at a time early enough so that approximately e45 fissions have occurred before maximum criticality is achieved.10 Based on his simplified model of the assemble system as Trinity’s, if a test yield is 2.7 percent of design yield, then it would be called a fizzle yield.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by Amber G. »

negi wrote: I did not get this ; in above case even if there was enough boosting gas how will the fusion initialize in the first place if the Pu of the primary does not attain critical mass . All in all the Pu in primary has to attain critical mass following the implosion event whether it is FBF or even a full fledged 3 stage TN ( I assume we are not implying that CE alone can initiate fusion).
FWIW: One does not need 'critical mass' for fission .. one needs enough neutrons to sustain fission (else it will die down).. if there are enough fissionable atoms close by the neutrons generated by each fission can start chain reaction. Generally critical mass is defined for a sphere (when one say, say 10Kg for Pu - It means spherical shape at normal density etc) but depending on shape, density, purity, temperature, are there neutron reflectors (which will not let neutron escape) etc.. etc. it can vary a lot... If you have neutron source, or can use more effectively those generated you may need much less material than those given in critical mass tables.
Hope this helps.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by shiv »

^^
I guess that is the difference between "critical mass" and "criticality". The critical mass is an absolute value that will cause fission/meltdown (or an explosion if it occurs suddenly) while criticality is achieved by compression to achieve a density that allows a chain reaction to initiate because the atoms are closer together and much more likely to get blasted by neutrons.

The crude Hiroshima/Nagasaki devices had actual critical masses while efficient FBF devices can have something far less than a critical mass.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by samuel »

In this day and age, we can all be google scientists.
Here is information about critical mass you must know:
http://en.wikipedia.org/wiki/Critical_Mass

:P

ps (http://en.wikipedia.org/wiki/Critical_mass)
Last edited by samuel on 19 Oct 2009 22:05, edited 1 time in total.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by Amber G. »

*** Edited by author *** OT
Last edited by Amber G. on 20 Oct 2009 01:52, edited 1 time in total.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by samuel »

So what was the yield then?
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by Amber G. »

I guess that is the difference between "critical mass" and "criticality". The critical mass is an absolute value that will cause fission/meltdown
Not to nitpick but just to add/clarify ; "critical mass" is defined (to make it a 'standard' value) as a "perfect spherical ball" of
such and such material will attain criticality...Loosely speaking people do calculate/say ... for example, for such and such shape and for such density ...the critical mass is such and such..FWIW (For example one can have more material than "critical mass" without it going boom, if one does not keep it in the shape of a sphere.. but say a sheet)
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by negi »

My reference to critical mass was in the context of a nuke where the critical mass is formed after the implosion event ; and again even for the neutron sources to sustain fission as in case of FBF the neutrons have to be generated by initializing the FUSION reaction which again requires the Primary to fission enough to enable compression of the boosting gas upto requisite levels and I don't think a sub critical nuclear assembly of the Primary in a N-bomb is capable of triggering FUSION.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by Amber G. »

^^^ again I am not clear what you mean by 'sub-critical' (yes by definition, sub critical is not critical) here.. anyway, for example critical mass (as seen in any text book) for say U235 is about 50 Kg (for Pu it is about 10Kg),...Most fission bombs do not use that much fissionable material...
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by negi »

Amber_G thanks clarifying ; it seems my impression about the term 'critical mass' was WRONG . I thought the term refers to the mass of fissile material required to sustain chain reaction in presence of a neutron source then be it at standard conditions inside a lab or inside a nuke under the action of conventional explosives after the implosion event. Again goes to show this topic is not for nanha mujahids like me to mess around with . :P
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by JE Menon »

Gentlemen, Arun_S has withdrawn from the forum and therefore cannot respond directly to several references to him made in this thread. I suggest, strongly, therefore that all such personal references end.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by Kanson »

http://forums.bharat-rakshak.com/viewto ... 31#p757831

The details given there pertains to the Fusion Bossted Fission weapon. As you go higher in increasing the yield, weight automatically starts increasing as you need more power in the form of chemical explosives to compress them.
Check the graph, once the weight starts increasing, the yield flattens out. So to compare the 500 kt fusion boosted fission weapon to 50 kt or 100 kt may not be correct.
The term Boosting is loosely used to mention two stage TN weapon. So in one or other way you may be right.

Added later: The answer to BARC capability on fielding higher yield FBF weapon relies on its theoretical understanding on the entire fission process. For any FBF to be successful the basic fission design should be really good. This is where BARC stands out and their confidence level of FBF weapons.
dinesha wrote:
Anujan wrote:
Now let us assume that a 12KT weapon is to be scaled to 60KT. There are two issues

(1) How much more Pu is needed ? How much more explosives are needed to bring the Pu together ? note that this might not be a linear function of the desired yield (double yield = double weight)
(2) Have we put in so much Pu that it can attain criticality without boosting gas ?

I dont know the answers. But its worth thinking about.
Relationship between fissile material (both Pu/U) and yield is skewed towards yield. Higher efficency is achieved in higher yield weapons. Tsar Bomba was most efficient of all the test..

For example: for medium tech. Capability and pure fission device:
1.5 kg of Pu or 4 Kg of HEU will produce a yield of 1 KT.
2.5 kg of Pu or 6 Kg of HEU will produce a yield of 5 KT.
3.5 kg of Pu or 9 Kg of HEU will produce a yield of 20 KT.
9 kg of Pu or 16.5 Kg of HEU will produce a yield of 100 KT.

Here is the link to the graph relating yield and quantity of Pu and HEU...
http://www.nrdc.org/nuclear/fissionw/fissionweapons.pdf
The details given there pertains to the Fusion Bossted Fission weapon. As you go higher in increasing the yield, weight automatically starts increasing as you need more power in the form of chemical explosives to compress them.
Check the graph, once the weight starts increasing, the yield flattens out. So to compare the 500 kt fusion boosted fission weapon to 50 kt or 100 kt may not be correct.
The term Boosting is loosely used to mention two stage TN weapon. So in one or other way you may be right.

Added later: The answer to BARC capability on fielding higher yield FBF weapon relies on its theoretical understanding on the entire fission process. For any FBF to be successful the basic fission design should be really good. This is where BARC stands out and their confidence level of FBF weapons.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by shiv »

Amber G. wrote:
I guess that is the difference between "critical mass" and "criticality". The critical mass is an absolute value that will cause fission/meltdown
Not to nitpick but just to add/clarify ; "critical mass" is defined (to make it a 'standard' value) as a "perfect spherical ball" of
such and such material will attain criticality...Loosely speaking people do calculate/say ... for example, for such and such shape and for such density ...the critical mass is such and such..FWIW (For example one can have more material than "critical mass" without it going boom, if one does not keep it in the shape of a sphere.. but say a sheet)
Ah yes - that is interesting - I never thought of that. So much for my Wiki degree. I only recall reading two instances of critical masses being achieved in a setting with humans about.

One was a book by/about Feynman who spoke of the heat felt while sitting next to a critical mass of U 235. The other may have been the 1998 Goa atom paper that I had put up - in which the author spoke of Pu masses being handled carefully but still sometimes "going critical" and "fizzing and spluttering". Need to see if I can dig that one up.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by Amber G. »

Pu masses being handled carefully but still sometimes "going critical" and "fizzing and spluttering". Need to see if I can dig that one up.
I am sure you know . that one cause of that is anomaly in Pu's crystal structure can cause problems ..and specially having Pu240 in the mixture. ..http://en.wikipedia.org/wiki/Critical_mass
A theoretical 100% pure Pu-239 weapon could also be constructed as a gun-type weapon. In reality, this is impractical because even "weapons grade" Pu-239 is contaminated with a small amount of Pu-240, which has a strong propensity toward spontaneous fission. Because of this, a reasonably sized gun-type weapon would suffer nuclear reaction before the masses of plutonium would be in a position for a full-fledged explosion to occur.
(Initial design of Gun type of Pu Bomb was changed mainly because the pu 240 ratio was slightly different from the one gotten from the Oak ridge reactor and the initial part gotten from other place which was used for calculations and prototype - The Gun type mechanism was thus changed for Pu device.. (One can dig it up the details, if interested)
Last edited by Amber G. on 20 Oct 2009 06:28, edited 1 time in total.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by Umrao Das »

JEM sar thats called hyper active decay
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by shiv »

shiv wrote: The other may have been the 1998 Goa atom paper that I had put up - in which the author spoke of Pu masses being handled carefully but still sometimes "going critical" and "fizzing and spluttering". Need to see if I can dig that one up.
No it was not the Goa atom paper which is here:
http://forums.bharat-rakshak.com/viewto ... 81#p739281

Anyhow a quote from that which is relevant in this thread..
Nuclear weapons that are not pure fission
weapons use fusion, the reaction that produces
energy in the sun, to enhance their destructive
effects. But these weapons require a fission bomb
to provide the energy to initiate the fusion reac-
tions. In these weapons, a few kilograms of a
Deuterium or Tritium gas mixture is included in the
centre of the fissionable core. When the bomb core
undergoes enough fission, it becomes hot enough
to ignite the D-T fusion reaction, which proceeds
swiftly. It turns out that I kg of Plutonium
suffices.
The D-T fusion reaction produces an
intense burst or high energy neutrons that causes
a correspondingly intense burst of fissions rate in
the core. This accelerates the fission rate in the
core, and allows a higher percentage of the material
in the core to fission before it blows apart. The
efficiency of the weapon can be further increased
by having a Uranium-238 blanket around the
central assembly, because the neutrons produced
in the D~T reaction have the right energy to split
the U-238 nuclei. However, an interesting method
exists that obviates this by the use of a solid fuel
in the form of Lithium Deuteride (LiD). When a
neutron from an initial fissile trigger strikes LID,
it produes Tritium and Helium. The D and T then
fuse to produce a lot of energy and lots of neutrons.
The device exploded on May 11 last year, had in fact
used LiD, but its energy yield was kept down
by using a mantle made up of non-fissile material
and reducing the amount of D and T.
.


Two points that catch my attention (after having OCRed in 1999 and having posted it several times and read it several times :roll: )
1) only 1 kg Pu in the primary? That is fantastic, if true
2) The May 11 device did not have a fissionable mantle
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by amit »

Umrao Das wrote:JEM sar thats called hyper active decay
So true. It's a part of the withdrawal symptoms of acolytes who just cannot stop bringing up the name even if no one else is interested.

BTW wait with Winter upon us I'm looking forward to playing in the Snow: Jai Ho!
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by Amber G. »

Sorry if it is already posted / xposted ..
WSJ Ope ed by Kyl:
Why We Need to Test Nuclear Weapons
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by Sanatanan »

I believe this link has not been posted before:

Pokharan II: The Incestuous Debate(October 2009, Vol. 2 , No. 10) by PR Chari, Research Professor, Institute of Peace and Conflict Studies
Santhanam’s disclosure that the thermonuclear (hydrogen bomb) test in 1998 failed to reach expectations was known earlier. Initial doubts emerged among weapons designers abroad whether Indian nuclear scientists could have contained the yield of the thermonuclear (TN) device at 45 kilotons (KT) in it its very first test. Scientific opinion in the West was divided on this question with skeptics claiming that this containment of the yield was very difficult in the first TN test; others urged that the passage of years and availability of open data had enabled Indian scientists to fashion a low-yield TN device; it was triggered by a fission core with a fissile ‘blanket’ around it to provide the second stage fusion reaction. Chidambaram had initially denied that a boosted fission device had been used, but later informed that it had, indeed, been the trigger for the TN device. These technical details about the bomb design must be recollected, since doubts have surfaced regarding the occurrence of a TN explosion and its actual yield.

It was estimated in the West that around a 25 kiloton yield had accrued based on seismic data. What the author heard from privileged sources at the time was that the first-stage boosted fission trigger functioned, but the second stage fusion reaction did not occur, resulting in a low yield of 20-25 KT being recorded. This unhappy fact is now being aired by Santhanam. The scientific community has ranged itself on both sides of the argument. Some others have not taken a stand on these technical issues, preferring to highlight the irrelevance of yield considerations for providing the matrix of nuclear deterrence

The question whether the TN device malfunctioned and its yield was far lower than the designed yield has to be satisfactorily resolved. Two sets of data exist with the DAE and DRDO. They need to be placed before a peer group from India and/or abroad to ascertain the truth, which is the accepted tradition to resolve scientific controversies. This however, may not happen. Why? The 1998 nuclear tests were conducted during the NDA regime with the BJP milking this event for its political dividends. But the successor UPA regime has remained content to let sleeping dogs lie, without trying to appreciate the strategic significance of a possibly failed TN device. Unfortunately, both the national strategic and political leadership in India are ‘babes in the wood’ as Santhanam colorfully described MK Narayanan

Reverting to the scientific inquiry for estimating the yield of the TN device, the accepted methodologies used are seismic evaluations and radiochemical analysis. It is alleged that DRDO relied only on the seismic method (close-inacceleration), since radiochemical analysis was done by the DAE. In a PIB handout Chidambaram said, “the DRDO data had anomalies and had to be rejected.” Santhanam argues that the DRDO estimated the yield of all the five nuclear devices tested during Pokharan II. The DAE accepted all these estimates, except for the TN device, suggesting selectivity in utilizing the DRDO data. Santhanam further argues that the crater formed by the TN device was 25 meters in diameter, consistent with a 25 KT nuclear explosion; in fact, he has also said that only a small depression was formed in the shaft mouth. Chidambaram explains that the crater size depends “on the depth of burial and the rock medium around the shot point, and the rock medium and the shot point.” How did these obvious facts escape the attention of DRDO?

Coming to radiochemical analysis, which is the most reliable method available, Santhanam only quotes what other DAE scientists informed him. As stated earlier, radiochemical analysis was only carried out by the DAE. Why DRDO did not undertake this analysis is a mystery. Chidambaram informs that sharp increases in the isotopes Mn-54 and Na- 22 were found in rock samples taken from the TN test site, suggesting a thermonuclear reaction occurring. Besides, the Mn-54/Ce-144 ratio was consistent with a fission-fusion reaction. Without access to the spectroscopic data, assertions in this regard can only be speculative.

There is another aspect to this matter. The yield of the Pokharan-I device is believed to have benchmarked the yields of the Pokharan-II devices. Raja Ramanna and Chidambaram estimated its yield to be 12 kilotons in January 1975, but serious doubts emerged about this claim, with a yield as low as 2 kilotons being suggested. Radiochemical analysis was apparently conducted, but the results were not made public. This controversy is significant since the seismological data from Pokharan-I was used to calibrate the yield of the Pokharan-II devices. Inflating the Pokharan-I yield would naturally affect the Pokharan-II test results.

This multitude of doubts, in fairness, requires an independent analysis of the TN test yield. A RTI application could be filed. It would be interesting to see if the Government denies this information on the ‘national security’ pretext.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by shiv »

Sanatanan wrote:I believe this link has not been posted before:

Pokharan II: The Incestuous Debate(October 2009, Vol. 2 , No. 10) by PR Chari, Research Professor, Institute of Peace and Conflict Studies
Chidambaram had initially denied that a boosted fission device had been used, but later informed that it had, indeed, been the trigger for the TN device.
Thanks for the link - I have archived it

Technically RC did not "deny" that it was a boosted fission device. He denied the western contention that only a boosted fission device was tested and insisted that it was a "thermonucelar device"

I went through many of the archived articles I have:

From May 18th 1998
http://www.indianexpress.com/res/web/pI ... 50634.html
Doubting the ability of Indian scientists to put together
a sophisticated H1bomb, the general agreement among
the US1based experts was that the Indian
thermonuclear device was not a hydrogen bomb, but a
``boosted fission device''.
<snip>
Chidambaram also pointed out that the thermonuclear
device or the hydrogen bomb used an advanced fission
device to trigger the thermonuclear core.The fission
trigger produced about 12 kilotonnes to activate the
thermonuclear core to ultimately yield 45 kilotonnes.


Then from 2000 I find:
http://www.indianexpress.com/ie/daily/2 ... 21024.html
Though the total yield of the two1stage thermo nuclear device was made
available, AEC intentionally neither gave the fission1fusion break up nor
declared the material of the device so that "nobody can calculate the fusion
yield," he said, adding that it consisted of a "fusion1boosting fission device" as
the primary stage followed by a fusion device.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by Sanku »

Sanatanan wrote:I believe this link has not been posted before:

Pokharan II: The Incestuous Debate(October 2009, Vol. 2 , No. 10) by PR Chari, Research Professor, Institute of Peace and Conflict Studies
Excellent summary of the so called fizzle position.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by Gagan »

The western guys must have thought :
1. That a FBF was tested
2. That the TN design was a sloika.
3. Tellar Ulam was a last choice.

As I've written before, here is the problem with even the radiochemical analysis.
If the primary was FBF there has to be some fusion occuring in its core with the DT fusing and giving off all those fast neutrons. Now this can cause the strange metals to appear in the radio chem samples. Essentially how do we know if the Fast Neutrons were from the FBF core or from the LiD secondary.

The reason why RC's claims seem suspicious is because:
1. BARC team accepted all the seismograph readings of all the tests except the reading of those around the TN.
2. The BARC team bolster their TN claim by saying that radiochem proved their findings, but as I've outlined, that is suspect.
3. The CORRTEX analysis was also dismissed as incorrect and/or faulty.

So essentially the only measure of failure that is now evident is by the yield generated. If the scientists know that the secondary was supposed to give a particular yield, that was not obtained, it means that the secondary did not perform or that it underperformed.

As we see, all these points do not seem to support each other.

They all align and support each other only when one considers that the device's secondary underperformed or did not undergo fusion at all. Then all readings - seismographs, radiochem, CORRTEX and crater diameter and depth all align.

JMT.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by NRao »

Sanatanan wrote:I believe this link has not been posted before:

Pokharan II: The Incestuous Debate(October 2009, Vol. 2 , No. 10) by PR Chari, Research Professor, Institute of Peace and Conflict Studies
This guy is way above his head. I am not sure if he knows what he is talking about in this case:
The question whether the TN device malfunctioned and its
yield was far lower than the designed yield has to be
satisfactorily resolved. Two sets of data exist with the DAE
and DRDO. They need to be placed before a peer group from
India and/or abroad
to ascertain the truth, which is the
accepted tradition to resolve scientific controversies
.
"And/or abroad"? Which country places her strategic data in front of anyone? Nuts.

Valid stuff:
Santhanam argues that the DRDO estimated the yield
of all the five nuclear devices tested during Pokharan
II. The DAE accepted all these estimates, except for
the TN device, suggesting selectivity in utilizing the
DRDO data.
Santhanam further argues that the crater
formed by the TN device was 25 meters in diameter,
consistent with a 25 KT nuclear explosion; in fact, he
has also said that only a small depression was formed
in the shaft mouth. Chidambaram explains that the
crater size depends “on the depth of burial and the rock
medium around the shot point, and the rock medium
and the shot point.” How did these obvious facts
escape the attention of DRDO?
Very good question. With Santhanam stating he expected a 70-72 meter radius crater, perhaps he was not aware how deep the device was placed? For IF he knew and it was 200+ meters then there should not have been a crater @ 45Kt.
This controversy is significant since the
seismological data from Pokharan-I was used to
calibrate the yield of the Pokharan-II devices. Inflating
the Pokharan-I yield would naturally affect the
Pokharan-II test results.
Eh? Granite (POK-II - S1) vs. non-granite (POK-I, non TN) - I doubt they could have used the same data. ??????. IIRC it was the Braneberry "model" that was used for S1 (depth).

Not a well written article IMHO.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by Gagan »

Now this is the situation that India's nuclear scientists found themselves in in 1998. They had only been given this one chance, and the TN perhaps did not go off as planned. We all know in retrospect that Narasimha Rao had held back on testing because he waited for the TN to come on line. When BARC thought they had it, this was conveyed to ABV by NR.

Now what could the scientists and india's leaders have done? The security situation around India was deteriorating then, with the pakistanis testing the N Korean missiles and the sino-pak nuclear cooperation in full swing, with the all knowing US fully aware but silently watching the tamasha. Domestically the BJP wanted to give something to the nation and its caders, I guess.

So the strategic imperatives demanded that the tests be declared successful, with the caveat that the issue of testing will be revisited at a later date when the team was confident.

I am also bringing up something Arun_S said here in those early days when he first started opposing the test results. His information was undoubtly from some senior chaiwala, perhaps from one of the dissenters whom we see and read about in the papers. I have heard Amitabh Matoo and other experts on DD, saying that the TN needs further testing, and this was ~ 6 months after the tests.

The point I want to make is that personally I am of the view that the TN underperformed / failed, but I don't agree with blaming and pointing fingers or name calling. Both RC and AK are respectable scientists, even though professional rivalry and jealousy will cause some to try and denigrate their achievements. They failed, but the cover up was mandated by the strategic imperatives and was undertaken by GoI no less. To there credit, they did apply to GoI for a further test series during the last years of the NDA term itself. The point here is, that the Nuclear Deal came by and has bound India to a kind of a CTBT situation, where India will have to extend its voluntary moratorium for some time.

Now the question is, why did India accept the nuclear deal at this juncture? The stated reason is that the N plants were really starved of fuel and were working to very low capacity with very little fuel in stocks. It transpires that the fuel shortage was artificial and was created because mining was held back due to some reasons. Now this could fall both ways. On the one hand is India's access to all tech, with the latest N tech coming by, the restrictions on the sale of high tech goods going away now, and on the other hand is the fact that India's nuclear deterrence is incomplete without a proofed TN.

GoI calculates that 25 or 50Kt Fission or FBF or untested 500Kt or 1MT TNs give adequate deterrence and so a Nuclear deal is justified at this point. Purists might disagree, many would find nothing wrong with this.

But the thing that we need to monitor is, is the Nuclear deal really being implemented in spirit by the US? Already there is some dragging of feet apparent on Enrichment tech. Further China has shown that with the US deeply indebted to them, the US has opened its doors to the chinese, and almost all tech is allowed provided the chinese can meet the price. If this is true, and India gets denied some tech that the chinese have access to, or that a china-pak tag team wants to pull an upset over India, then India will begin to consider giving up the moratorium as soon as it feels that the US investment is sufficiently stuck in India to be unable to pull out without serious harm to itself.

JMT
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by negi »

Gagan wrote: As I've written before, here is the problem with even the radiochemical analysis.
If the primary was FBF there has to be some fusion occuring in its core with the DT fusing and giving off all those fast neutrons. Now this can cause the strange metals to appear in the radio chem samples. Essentially how do we know if the Fast Neutrons were from the FBF core or from the LiD secondary.
Yes it is a problem but for those who are not aware of the design specs as to how much LiD went into primary and secondary . For some one who knows how much LiD was used there must be means to verify the post shot readings.I wish these things were so simple. 8)
The reason why RC's claims seem suspicious is because:
1. BARC team accepted all the seismograph readings of all the tests except the reading of those around the TN.
I am yet to see a tabulated report with columns showing BARC vs DRDO readings.Point being there can be chances that readings for other devices too did not match (which is nothing unusual) for the whole idea is to estimate the YIELD with as many different methods as possible.
3. The CORRTEX analysis was also dismissed as incorrect and/or faulty.
Where ? I did not see any such report. Btw since the tests were simultaneous won't CORTEX measure the cumulative Yield instead of just for TN ? :-? :?:

And I don't think even PKI or KS ji have questioned the cumulative YIELD numbers.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by Sanku »

negi wrote: Where ? I did not see any such report. Btw since the tests were simultaneous won't CORTEX measure the cumulative Yield instead of just for TN ? :-? :?:

And I don't think even PKI or KS ji have questioned the cumulative YIELD numbers.
No there were reports that BARC carried out CORRTEX but also rejected the same. Also why does CORRTEX have to be cumulative?

Different cables for different shafts would be used. Surely the destruction of cables in different shafts did not show any interference (like seismic signature)

K Sanathanan also says DRDO carried out fiber optic based "advanced tests", those I took to mean DRDOs version of hydrodynamic testing/CORRTEX -- but right now does not have a clear official confirmation of my understanding yet.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by Sanku »

NRao wrote: Very good question. With Santhanam stating he expected a 70-72 meter radius crater, perhaps he was not aware how deep the device was placed? For IF he knew and it was 200+ meters then there should not have been a crater @ 45Kt.
Highly unlikely, next to impossible.

More likely that KS is sending a message, to be decoded by assuming higher yields.
Eh? Granite (POK-II - S1) vs. non-granite (POK-I, non TN) - I doubt they could have used the same data. ??????. IIRC it was the Braneberry "model" that was used for S1 (depth).
It would affect at least one component (s2) right.
Not a well written article IMHO.
But sums up the open questions very well. The first listing of points raised so far.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by Umrao Das »

"Its all matter of S(p)oil Mechanics"

old saying of Naked Sage Fakhuruddin PBUH
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by NRao »

Sanku wrote:
Highly unlikely, next to impossible.
Certainly hope so.
More likely that KS is sending a message, to be decoded by assuming higher yields.
Like what?
It would affect at least one component (s2) right.
Even Santhanam says S1 is the issue, so how does that impact S1? In fact from the Toman equations it should not impact it at all!!! (I am glad you did not bring up the other three devices though. :))

I am open to suggestions (with reason).
But sums up the open questions very well. The first listing of points raised so far.
We need that other shoe to fall, not another summation - a very poor one at that.

Seriously, I took a quick look at some of his other "sayings". Not impressed at all.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by NRao »

Is there a lack of peer review on articles written in India and certain lack of editorial review? Not to mention half baked reports. we can do better.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by enqyoob »

A week away from the internet - I see that I have not missed much.
I went through many of the archived articles I have:
shiv! How CAN you be so cruel? That would be called
Effect of safety pin on rubber hot air balloon


I see that the latest fizzlexpert conveniently omits the Khetolai Certainty. Figures. Should be worth another 5 pages, though.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by Amber G. »

NRao:

FWIW: Prof Chari has been quoted/discussed quite a few times in BRF (For example under the thread Pakistani nuclear doctrine reading list ). even way back in 2003 Ramana garu summed it up after discussion of
India and Pakistan could cross the nuclear threshold without wanting to
Its pathetic of Chari an ex-IAS to write such tripe. Guess will wrtie for a few $ and a littel lime light. Another Deracinated Internationlized Elite
((BRF post Aug 29, 2003)

Just some background info, I am sure, most know here.. that, just to take a random quote:
The ruling BJP party believes that using Pakistan as the external and Muslims in India as the internal scapegoat for its failures could be translated into votes.
.. was part of Prof Chari's article about India/Pakistan's nuclear threshold discussion..
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by Gagan »

N^3 saar,
If you post that Khetolai post of yours one more time, I promise I shall depart for JEEHARD on the BENIS dhaga. :((
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by NRao »

N^3,

What is Gagan talking about?
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by NRao »

Amber,

I have not followed him at all, but the more I read (including his stint on PBS!!!!!!!!) he is rather horrible ......... IMHO.

Perhaps that article is his best in the recent past and even that is not good.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by Sanku »

From the article above by Shri Chari
others urged that the passage of years and availability of open
data had enabled Indian scientists to fashion a low-yield TN
device; it was triggered by a fission core with a fissile
‘blanket’ around it to provide the second stage fusion
reaction.
Does this mean that the blanket around the boosted-fission/fusion device was indeed fissile and not inert at all?

Meanwhile Amber G et al. It would be good to not shoot the messenger. This appears to have become way to common here where we are too eager to rip the person apart and talk of the message.
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Re: Pokhran II not fully successful: Scientist - Part-3

Post by Gagan »

NRao wrote:N^3,

What is Gagan talking about?
Err,
Merely that the yield was controlled because of the proximity of Khetolai.
The tests were a success.
:oops: N^3 saar has posted this several times and the jingo junta has posted the conspiracy theories even more number of times. :P
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