Nuclear Discussion - Nukkad Thread: 16 Apr 2008

[darshan]

[quote="Gerard"][url=http://www.thaindian.com/newsportal/unc ... 40141.html]India’s energy security at “riskâ€

[ramdas]

Arunji,

When you say S-1 had used 8 kg fissile material, around 2+ kg went for the primary. So that gives 6 kg for the secondary of which ~0.5 kg goes for the spark plug (say) . Since 40kt fusion yield was expected, it means about 1.3kg of LiD at ~50% efficiency. Only ~5.5 kg of tamper for a secondary of about 1.8 kg mass ? That sounds too little. Sublette's site says that the tamper should be 8-16 times as heavy as the secondary. Did the wholw thing fail because the design was not conservative enough ?

[Arun_S]

Arunji,

When you say S-1 had used 8 kg fissile material, around 2+ kg went for the primary. So that gives 6 kg for the secondary of which ~0.5 kg goes for the spark plug (say) . Since 40kt fusion yield was expected, it means about 1.3kg of LiD at ~50% efficiency. Only ~5.5 kg of tamper for a secondary of about 1.8 kg mass ? That sounds too little. Sublette's site says that the tamper should be 8-16 times as heavy as the secondary. Did the wholw thing fail because the design was not conservative enough ?

I am not privy to the construction details. I just a smart (some say dumb) psy-op analyst.
Well tamper does not have to be one piece shell, or for more creative solution a bimatellic construction with the outer layer made of cheap Nat-U that anyway gets ablated away leaving a highly compressed pusher to do the heavy duty work.

[Sanatanan]

I visited Tarapore recently. Plant visit. Exquisite experience.

Perhaps you could share your experiences in these pages with fellow BRF members who have not had this opportunity.
TIA.

[Neshant]

> Perhaps you could share your experiences in these pages with fellow
> BRF members who have not had this opportunity.

No you should not.

There are all kinds of intelligence agencies and snoops visiting BR. If you have classified or important info, keep it to yourself.

[ramdas]

the paper at arxiv.org/0401110.pdf says that if a TN of 150kt with U-238 tamper is equipped with inert tamper, its yield will be abt 50kt. So, this is indeed a possibility for S-1. Even so, a full yield test will be more convincing.

[Arun_S]

the paper at arxiv.org/0401110.pdf says that if a TN of 150kt with U-238 tamper is equipped with inert tamper, its yield will be abt 50kt. So, this is indeed a possibility for S-1. Even so, a full yield test will be more convincing.

Boss put to use "reductio ad absurdum" logic. by answering 2 pertinent questions
1. Which one was the one that used 8 kg?
>>> One can eliminate all other choices as invalid except that it went into S1. And specifically of the 6 kg of the 8 kg can only be purposefully used as tertiary stage doubling as temper for second stage.

2. Where and how did the 6 kg disappear without fissioing in any way; specially when it is compressed by ablative outer temper?

Its for you to assess the true nature of S1.

[NRao]

What is gained by the likes of Carl Bildt touting the nukular deal? Those apprehensive of US designs on Indian nuclear weapons capability can hardly be reassured that CRE advocates like Bildt are supporters... especially when he mentions CTBT in same breath... the NSG meeting will be interesting...

What is really strange is that ALL these guys speak as though the world would be the best place to live in IF India signs the NPT and CTBT!! Kissinger, Bill Clinton, etc included.

[Kalantak]

Nuke deal only after decision at political level : Kakodkar

Agartala

India would discuss the civil nuclear deal at the IAEA only after a decision at the political level, Chairman of the Atomic Energy Commission, Anil Kakodkar said on Monday.

Asked about the fate of the nuclear deal, he said domestic discussion was on at different political levels and India would hold discussions in the IAEA only after a decision.

Asked if the deal would be a threat to the country's sovereignty, he evaded the question saying that in any deal both sides would like to push their conditions. "Everything is clearly mentioned in the 123 Agreement," he said.

Kakodkar, who also delivered a lecture in a 'Meet the scientist' programme organised by the Agartala chapter of Institution of Engineers here, said, "We must design our own nuclear programme which is self reliant, indigenous, consistent and capable of use with our own resources."

He said, "our predecessors like Homi Jehangir Bhaba visualised that there would be no free nuclear exchange and we would have to sacrifice something to get something."

Kakodkar said, "We cannot compete in any sector with borrowed technology because they would never give us better technology. But despite all that, we need the civil nuclear deal with other countries to meet our additional requirements."

He said, by 2050 India would be a leader in many sectors and emerge as an economic giant which would be able to produce 1300 GW of Power (1300X1000 mg watt) from nuclear energy.

By 2050, fifty per cent of the population in the country would be youths and given the opportunity, they would be in a position to be global leaders, Kakodkar said.

[Kanson]

RC showing the data is construed as RC's own data ?

This post is to say that i'm alive and revert in 1 or 2 days.

[ramdas]

Arunji,

But there were six devices really. One of which was finally not tested. The fissile cores of these were from 3-8kg. So, the 8 kg weapon could have been the sixth one as well. Moreover, even for the sub-kt tests, there is no reason why one of them need not have a large core. Lesser explosive compression and lack of boosting may still ensure a sub-kt yield, the test being designed in order to understand the behaviour of large cores/understand equation of state issues etc.

At least, going by what you say, explosive driven implosion is very thoroughly understood by our weapons design establishment. There are two reasons for which a Teller-Ulam TN is ideal . Weight and conservation of fissile material.

The way I look at it is that the deterrent should be made to grow in phases. Currently we are only in Phase 0 - having a bunch of Agni I and Agni II deployed w/ gas boosted fission weapons perhaps. Such a warhead shall weigh ~700kg for a 200kt yield incl. RV.

Somehow our political leadership lacks the spine to go for another TN test that will enable an optimal arsenal. An interim solution that I shall refer to as Phase 1 should be a build up for now of Agni III and Agni III+ missiles equipped with sloika warheads.

The advantage of the sloika is the following. Even though yield/wt ratio is like that of a gas boosted fission device, it saves on fissile material. For example, a 40kt fissile core in Joe-4 is said to have given a 400kt yield with LiD blanket and U-238 tamper. This seems to require explosive compression and not radiation implosion, and so, a reliable device of this type should be possible to produce. This is what Israel seems to have done quite profitably. In our case, a 700kg sloika w/ 200kt yield (20kt fissile core) should be the standard warhead for Phase 1 deployed on >100-150 agni iii/iii+. Moreover, we should give up the no first use commitment. This would be a deterrent that should ensure that there is no military action against India even in the event of a future test (The reach of such a deterrent would be >12000km).

At an opportune moment after Phase 1 is fully operational, a series of 2 stage TN's should be tested to go to the next Phase. This should gradually replace the first generation warheads, leading to a larger number of warheads for the same number of delivery systems. The thing to focus on should be to get Agni III/III+ in service ASAP and build them in large numbers. After all over 400 SS-20's were deployed.

[Anujan]

Arun_S, Kanson and other Rakshaks, Just my two cents and sorry for the provocation.

All this discussion about yields and weights are very very interesting. Arun_S's informed posting, Rakshak's contributions, criticisms all add to a healthy, informative and fascinating debate. Having said that, I think that going into the specifics of the design and RC said PKI said is losing sight of the original problem we set out to handle. Is further testing necessary ? I believe, absolutely positively yes. That is irrespective of whether S1 succeeded or not. The reasons are as follows:

1. We have not yet conducted a full yield test. Assuming a minimum 100KT boosted fission device as the backbone of our arsenal, (MIRV'ed into A-III), when did we ever conduct a 100KT test ? Forget testing if the bum is a dud or not, don't we need to test Rad-hardening, vibration and temperature resistance ? (note that they are going to be mounted in A-III and note the re-entry temperatures and vibrations, also note that they are likely to be attacked on the ground with conventional and radiological weapons). What is the impact of aging ? Will our bums assembled today work 5 years into the future ?

2. Given that our nuke posture is credible assured retaliation, and given that a nuke exchange is an unthinkable last resort action, should we leave the effectiveness of our designs to chance ? Note that pakis and Israelis dont need to test. Paki bomb is based on the philosophy that if IA comes knocking in lahore, a shaheen II with their bum will be headed to Mumbai. It may or may not be a dud, but do we want to take the chance ? Israelis considerations are similar. As long as middle east dont develop nukes, their nuke is a insurance policy against Arab-league type ganging up. If IDF is unable to resist a gang-up of all Arab countries, nukes will go out flying to all Arab capitals. They may be duds, but who wants to take the chance ? We on the other hand, will press the button only when half of us are already gone. If ours doesnt work, the rest of us will be gone too. Under this scenario, what is all this "I will use computer to run simulations onlee" argument ? Even a stupid tank shell is tested 100's of times !

3. The issue of testing can be debated without dragging in RC's or PKI's patriotism or animosities. Even if S1 yielded 150% of expected yield, there is no doubt in my mind that we should test at full yield in a shaft. We should test at full yield after dropping it from an aircraft. We should test at full yield on top of AIII, Mirved on top of AIII or any other future missile we might develop, test at full yield from ATV, test at full yield from a railway bogie. Test at full yield every year as national celebration of diwali dhamaka. Test at full yield during the retirement of every BARC scientist and their daughter's weddings. Our Brahmastra cannot fail us when we need it !

[ramdas]

Bharat Karnad in his book "Nuclear weapons and Indian security" also mentions BARC people informing him that a 100kt weapon weighing 200-300kg was available in the late 80's. So, this must have been a boosted fission weapon. So, a similar performance for a sloika with weapon weight of ~250kg and RV weight of about 350kg (with carbon fibre RV) should be possible. The advantage of the sloika being lesser use of fissile material. Or, if reactor grade Pu will work fine, boosted fission designs with the same yield/weight specifications may themselves suffice. At 10kg RGPu per weapon, a sizeable first generation arsenal of ~1000 warheads will be possible. At 3-4 RV's per Agni III/III+, a first generation arsenal would have to have ~300 of these delivery vehicles. Suboptimal, but may still be OK if we are not utterly spineless when push comes to shove. Moreover, giving up this no-first-use commitment may make things better.

[Gerard]

We should test at full yield after dropping it from an aircraft. We should test at full yield on top of AIII, Mirved on top of AIII or any other future missile we might develop, test at full yield from ATV, test at full yield from a railway bogie.

India is a signatory to the PTBT so there will be no tests in the atmosphere.

BTW, it was India that in 1954 first proposed a treaty banning nuclear weapon tests.

[Arun_S]

Bharat Karnad in his book "Nuclear weapons and Indian security" also mentions BARC people informing him that a 100kt weapon weighing 200-300kg was available in the late 80's. So, this must have been a boosted fission weapon. So, a similar performance for a sloika with weapon weight of ~250kg and RV weight of about 350kg (with carbon ... .. . .. . . .

Been caugth with their pants down two times, DAE can't be selling class "C" stocks and bonds, and more importantly India and Indian people responsible for security can't be buying those stocks at face value.

Like that Californian SOB who said: "TRUST BUT VERIFY"

VERIFY and VALIDATE IT HAS TO BE.

India should test NOW and test enough times thereafter to ensure blade of Brahmastra in stock work and are not rusted.

The gora RAAKSHAK does it as part of national policy, what DHIMMITUDE INDIA has in its policy to NOT DO IT on matter of sovereignty based on EQUALITY and PARITY ?

[Arun_S]

Cross posting couple of posts from yesterday at "International nuclear watch & discussion -28-Mar-08" thread.

[quote="Arun_S"][quote="Gerard"]Reactor-Grade and Weapons-Grade Plutonium in Nuclear Explosives

The International Thermonuclear Experimental Reactor and the Nuclear Weapons Proliferation Implications of Thermonuclear-Fusion Energy Systems
http://arxiv.org/pdf/physics/0401110
[quote]The nuclear weapons proliferations implications of the siting of ITER in Japan is enhanced by the fact that Japan is already in possession of a large stockpile of separated plutonium. Indeed, large-scale availability of tritium would enable this reactor-grade plutonium to be used in highly efficient and reliable nuclear explosives “boostedâ€

[NRao]

The following quote should lay to rest the argument that India will be able to make money on the deal outside of pure energy generation:

Nuke deal only after decision at political level : Kakodkar

Kakodkar said, "We cannot compete in any sector with borrowed technology because they would never give us better technology. But despite all that, we need the civil nuclear deal with other countries to meet our additional requirements."

Even if India signs on to GNEP she will never have an equal status.

[ramdas]

Of course testing a corrected version of S-1 is the best response. However, are we going to get a political establishment that will do it ? Not in the near future it seems, unless the NDA by chance returns to power.

This is why I looked at the boosted fission/sloika option. This is likely to work, given that S-1 primary worked, and given the sub-kt tests. These indicate an intimate knowledge of chemically driven implosion systems. OTOH, radiation implosion has yet to be mastered. Hence, even in the next round of tests, it is good to keep a 100kt odd boosted fission/sloika /both on standby in case the corrected S-1 fails again.

[SaiK]

Though our requirement and intention to sign the deal is entirely well understood by the cream of scientific layer at strategic levels (not at aam junta), the political level of understanding can't be stated at those levels, rather at aam junta levels., in fact lower than that considering the qualifications of many chai-biskooters who are driving the decision making seat.

These are the drawbacks, that CREing unkil could exploit, and show the world, how much respect really India needs, and actually on paper prescribing a different picture of the solutions.

We all should agree now, its the politics and Indian politicians who ruin our long cherished dreams. Without these wrong men at wrong places, we would have been with the right people and the right countries as friends... long long back.

[Gerard]

N-graphite export bid: Mumbai firm in dock

[ramana]

So Indian export laws do work unlike what the NPA were pontificating- David Albright and S Basu!

[sanjaykumar]

As has been demonstrated-nudge, nudge, wink, wink.

[raja_m]

Don't know if this was posted earlier. Apologies if this is repost, but watching an active discussion between Kanson & Arun_S this is worth a read I suppose.

Link- https://www.llnl.gov/str/Walter.html



Livermore researchers then compared the seismogram from the May 11, 1998, tests with India's May 18, 1974, single test (its only previous nuclear test) using data from stations in Canada and Scotland that recorded both events. The 1974 test generated a clearly detected teleseismic signal with an mb of 4.9. Because India declared the 1974 explosion a "peaceful nuclear explosion," some information about it was reported, such as the fact that it was a single explosion at a depth of 107 meters. However, Indian scientists and officials stated a large range in the yield estimate-4 to 12 kilotons.
Figure 4 shows the seismograms from the 1974 and 1998 tests using data from the Canadian station (for ease of comparison, the 1974 test's amplitude is doubled to match that of the 1998 test.) The two seismic waveforms show remarkable similarity.

Source - https://www.llnl.gov/str/Walter.html[url]

Another Old but Related Article -

Sources said that, while the U.S. has not made any public comment about what it knows about the Indian H-bomb test, the Clinton administration has raised the subject with the Indian government in secretive, high-level talks with New Delhi over terms under which India would agree to comply with the Comprehensive Test Ban Treaty (CTBT). The Indian side has asserted that the discrepancy between measured yield and the DAE claim of 43 kilotons is accounted for by a precautionary reduction by DAE of the amount of fuel used in the secondary, in order to prevent damaging the village of Khetolai, located only a few miles from the test site. U.S. analysts have concluded that was not the case. ''The Indians are hopping mad that we don't believe their H-bomb worked,'' one source said.

But the matter has now severely complicated the U.S.-Indian talks on the test ban, diplomatic sources observed last week. Because the H-bomb test failed, DAE ''is under intense pressure to test again,'' one U.S. official said. According to an official at the U.N. Conference on Disarmament in Geneva, ''The U.S. has been preparing to let India climb down'' from heavy sanctions which were applied nearly immediately after the May test series, provided India agrees to the CTBT. But if DAE didn't deliver on the H-bomb test, he said, the U.S. ''will have to give India a lot more in return'' for a firm agreement to agree to the CTBT. Diplomatic sources said that, in 1997, India had asked the U.S. for test simulation data, such as that the U.S. agreed to supply France a few years ago, in order to permit India to accept the CTBT, but that the U.S. had refused. One analyst said that ''it would now be logical'' for India to renew that request.

Source - http://www.bu.edu/globalbeat/nucwatch/n ... 12698.html[/url]

[raja_m]

Our Nuclear Scam?
B. K. Subba Rao

source - http://www.indiatogether.org/manushi/is ... kharan.htm
....

{full article text body removed by Arun_S: (Admin hat on)}

[Gerard]

Our Nuclear Scam?
B. K. Subba Rao

The B K Subbarao Espionage Case

The DAE and the Sahar Police had said very clearly that they had their man, but many Indians on the internet seem to be more keen to think that the Sahar Police and the DAE were wrong and they improperly imprisoned Capt. Subbaro. All this was carefully regurgitated before a friendly Indian media audience by the Non-Proliferation experts after the 1998 tests to "prove" GoI's incompetence. Ofcourse Capt. Subbarao himself went on to make allegations of DAE's involvement in criminal activities like smuggling and black marketeering. Not long after that he went on to talk about the incompetence of the DAE and the Indian establishment on every fora that the Non-Proliferation community could lend him.

an American observer - no less than their ambassador in Delhi himself - has indicated that Capt. Subbarao was indeed an American Confidential Informant.

[Gerard]

The two seismic waveforms show remarkable similarity.

Actually they don't.

Take a closer look at the 'squiggles'... their initial drop, subsequent drop and double bumps etc.
I prefer the term 'squiggle' to 'waveform'.
To use waveform terminology with this rubbish is an insult to physics.

A while back shiv wrote this...
Seismology for Dummies: Guesstimating nuke test yields

Now that is really really funny, and its called science. If some seismographs indicate a value of 5.2 for mb you apply the magic formula and get a nuclear yield of 53 kilotons if you use a value of "a" as 3.9, and the SAME NUCLEAR EXPLOSION will show a yield of only 8 kilotons if you use the value 4.5 for "a". How convenient.

take a read.... and please lookup the constant values for Nevada test range etc. Google on how these constants are determined... how a test site is calibrated etc...

[Kalantak]

Our Nuclear Scam?
B. K. Subba Rao

Why are u wasting our bandwidth by posting irrelevant and dated news items here?

[Arun_S]

Raja_m: Please stick to the topic of this thread, and add something new to the discussion instead of digging up old hacks?

The yield of Pok-1 and Pok-2 has been discussed in many old threads, you may review them in BRF Archive folder. And Pokhran actual yield by itself is now largely agreed & understood and converge to small variance.

[ramana]

The point to understand is not the yields of POK I and II but the expected yields. There is confusion about the two. The first is clear. the yields are what they are. PKI's arguement is that it was not what was expected.

Again we need to go back to Rao. When he decided to test in 1995 the TN was not ready and there wouldnt have been another opportunity. Yet he was ready to test. In 1998 the TN version was tested as it was ready.

Beyond accusing people of incompetence and other brutus fulmen, there is something else going on that we need to understand.

[vsunder]

So somebody at BARC told Karnad they had a 100 kt BF device. As I said before the shaft for S-1 was meant for 100kt keeping within safety factors( see Monitor article). So it becomes clear that that shaft was for the BF device at 100kt if it were to be tested. Now they wanted to test a TN, so the design yield was ...........

[ramana]

vsunder, Sorry for the digression but you need to point me towards the math of infrequent large events? Will take it up in the nukkad thread.

[ramdas]

So somebody at BARC told Karnad they had a 100 kt BF device. As I said before the shaft for S-1 was meant for 100kt keeping within safety factors( see Monitor article). So it becomes clear that that shaft was for the BF device at 100kt if it were to be tested

This sounds more correct. Also, POK-I at ~13kt produced a crater correponding to a PNE for a ~107mtr burial depth. So, the yield for a similar crater for the S-1 shaft which was ~200mtrs deep would have been ~(200/107)^3.4*13 ~ 110kt. IMHO this was about the maximum yield the shaft for S-1 could have held. So, it is unlikely that S-1 itself was designed for full 200kt yield. About 100kt designed yield sounds correct. With inert tamper. Accounting for the spark plug as well, this should be about 65kt fusion yield. However, the fusion yield seems to have been about 10 kt or so. This also matches with RaviCV's assertion that fusion yield was ~20% AFAI recall.

[ramdas]

Ramanaji:

From what you say, it looks as though the powers that be are happy with a limited arsenal. Why this restraint and hesitation to pursue national power ? This should be done uncompromisingly.

[Gerard]

xpost
Diplomats: US compromises on nuclear technology exports

The compromise... could complicate efforts to put life into a U.S.-Indian deal that would allow transfers of sensitive nuclear technology to New Delhi, even though it remains outside of the Nuclear Nonproliferation Treaty.

The U.S. shift also could hurt the chances that India can cut a deal with the suppliers group giving it greater access to nuclear technology even though it remains outside the NPT.

The U.S. wants the suppliers group to approve exports of nuclear fuel and technology to India, which has been cut off from international atomic markets because of its refusal to sign nonproliferation accords or accept outside inspection regimes.

"The Indians have been insisting on having access through the NSG to enrichment and reprocessing-related technology and this propose, which is now being backed by the vast majority of NSG countries, would bar the transfer of these two technologies to India, which is not a member of the NPT," said Daryl Kimball executive director of the Arms Control Association in Washington.

[Gerard]

India bristles at US comments on Ahmadinejad visit

India on Tuesday told Washington to mind its own business after a US official said New Delhi should urge Iran to curtail its nuclear programme during a visit by President Mahmoud Ahmadinejad.

[ramana]

I dont know. Might be generational and also a capture of national aspirations.

BTW WOP says over 200m not just that value. An increase of 50m brings the whole thing suspect.

Anyone with WOP. In his refs he says the sq m of the steel used to line the shaft and that it could hold two people together. What was the sq m quoted?

I assume 0.75m dia per person(might have too much idlis!) ie is 1.5m dia. We can calculate the height of the shaft from the formula Pi*D*H = sqm meters quoted.

[Arun_S]

So somebody at BARC told Karnad they had a 100 kt BF device. As I said before the shaft for S-1 was meant for 100kt keeping within safety factors( see Monitor article). So it becomes clear that that shaft was for the BF device at 100kt if it were to be tested

This sounds more correct. Also, POK-I at ~13kt produced a crater correponding to a PNE for a ~107mtr burial depth. So, the yield for a similar crater for the S-1 shaft which was ~200mtrs deep would have been ~(200/107)^3.4*13 ~ 110kt. IMHO this was about the maximum yield the shaft for S-1 could have held. So, it is unlikely that S-1 itself was designed for full 200kt yield. About 100kt designed yield sounds correct. With inert tamper. Accounting for the spark plug as well, this should be about 65kt fusion yield. However, the fusion yield seems to have been about 10 kt or so.

Few flaws in above logic:

• 1. Depth is determined by Design Yield not actual yield + safety factor.
  
  2. Assumes Pok-1 actual yield was design yield
  
  3. Assumes the Pok-1 crater is ideal and operted at upper threshold of the shaft and any higher yield would have released radioactivity.
  
  4. Pok-1 shaft was special. Documented to be a very large volume room (IIRC 13 m celing), with unknown de-coupling efficiency and its quantitative impact on burial depth and crater morphology unknown.
  
  5. The 100kt TN design yield of S1 is incompatible with use of 8 kg Pu material.

As an aside, amazing to note that accurate wooden model of Pok-1 was buried in the shaft, hoping it will be destroyed with the device. After the test that wooden model was embarrassingly thrown up intact and landed on top of the crater. (Now housed in BARC).

This also matches with RaviCV's assertion that fusion yield was ~20% AFAI recall.

As I recall he mentioned the 20% yield in different context, and it was not yield from LiD (pure fusion); LiT has disproportionate effect, and no one knows its role in that 20%.

[Arun_S]

I assume 0.75m dia per person(might have too much idlis!) ie is 1.5m dia. We can calculate the height of the shaft from the formula Pi*D*H = sqm meters quoted.

The lift used in old buildings and office with 1.5m sided square footprint (2.25 m2) generally carry 6-8 people. I find it difficult to image that for a militayr tunnel will use more spacious foot print (1.5m dia = 1.77 m2) for 2 person.

I think 1m dia is more reasonable bore dia (area=0.78m2) for 2 person.

I have WOP and can later tell you the surface area.

[ramana]

OK 1.5m dia might be too large. And 1m is too small like folks on skinny diet. How about we settle half at 1.25m?

[SaiK]

silly q: Does the yield measure by radiochemical analysis change by the type/strength of filling construction/materials used to close the shaft?