On Oct 18, 2011, at 4:25 PM, David Roberson wrote:

Hi Horace,

Thank you for the kind welcome into vortex. I suspect that my oversized attachment tunneled through the barrier; maybe using the same path as Rossi's device.

It must have a long de Broglie wavelength. My guess is the mass of paper involved is very low. 8^)


You have written an interesting description of the old ECAT version and I plan to review it thoroughly as time allows. I guess I may have needed a hit on the head to believe everything(or anything) that I read on line about ECAT operation. As you know, I was just parroting what I saw in the journal.

No problem there! Most discussion here is based on second hand information.


My understanding of nuclear physics is lacking as my field is electronics design. Allow me a lot of slack when I suggest something totally whacko as sometimes I have good ideas and approach problems from different perspectives.

New ideas are most welcome here. Slack is sometimes hard to come by! 8^)


Now, let me ask you a few questions that I suspect you can answer easily. You have presented some interesting calculations concerning the penetration of gamma rays and x rays through lead. The new ECAT design has 5 cm of lead according to reports. That is more than twice the original thickness of 2 cm in the earlier version. Could you help me to reverse engineer the ECAT shielding and figure out what energy of gamma rays would be just barely shielded enough to be undetected?

Here is a spread of results, but for 5 cm thick lead:

again using for I0:

 Energy    Activity (in gammas per second) for 1 kW
--------   ----------
1.00 MeV   6.24x10^15
100  keV   6.24x10^16
10.0 keV   6.24x10^17

and using:

   I = I0 * exp(-mu * rho * L)

where mu  is given by:

 Energy    mu (cm^2/gm)
--------   ----------
1.00 MeV   0.02
100  keV   1.0
10.0 keV   80


For 1 kW of MeV gammas we have:

I = (6.24x10^15 s^-1) * exp(-(0.02 cm^2/gm) * (11.34 gm/cm^3) *(5 cm))

   I = 2.07x10^15 s^-1   (  was 3.7x10^15)

For 1 kW of 100 keV gammas we have:

I = (6.24x10^16 s^-1) * exp(-(1.0 cm^2/gm) * (11.34 gm/cm^3) *(5 cm))

I = 1.4x10^-8 s^-1 = ~0 s^-1 (I posted 2.9x10^5 s^-1, but this was my calc. error - correct value was 3.04x10^4 s^-1, still readily observable with a counter)

For 1 kW of 10 keV gammas we have:

   I = (6.24x10^16 s^-1) * exp(-(80 cm^2/gm) * (11.34 gm/cm^3) *(5 cm))

   I = ~0 s^-1  (was ~0 s^-1)

So, the answer is the 5 cm of lead vs 2.3 cm of lead essentially eliminates gammas in about the 100 keV range that were readily countable with 2.3 cm of lead.

The extra lead does nothing, however, for converting more gamma energy to heat. It still does not prevent MeV order gammas from being readily detected, so they are still ruled out as a heat source. The 3.04x10^4 counts/sec of 100 keV gammas eliminated represent the unobservable 4.8x10^-10 J/s ~= one trillionth of a watt, so no added heat is obtained there, but even close up counting is prevented.


And, if this thickness is not adequate, is any amount of shielding able to stop gammas to that degree?

The extra lead does nothing for 1 MeV gammas, but a lot for 100 keV gammas, but also nothing for producing more heat. The lead can however, add to the heat-after-death time significantly depending on configuration. Frankly I suspect the added shielding is iron, not lead. It can sustain heat-after-death much better and provide stability at high temperatures that lead can not. The goal of this test was heat-after-death.

The mu for lead at 100 keV is 0.372. For 1 kW of 100 keV gammas through 2.7 cm of iron I get:

I = (6.24x10^16 s^-1) * exp(-(0.372 cm^2/gm) * (7.87 gm/cm^3) *(3 cm))

   I = 4.66 s^-1

The counts still effectively disappear with iron on the inside and lead on the outside or vice versa. If it is a hoax then there is of course no need for the lead at all.


I would suspect that if you answer no amount of lead is within reason, then you must think that the ECAT is a scam since the shielding is arbitrary.

I see no reason to go from 2.3 cm to 5 cm, since the prior counts were already nominal with regard to safety.


Rossi has stated that all of the energy released by the LENR process is in the form of photons. Do you think that this is possible?

Anything is possible. Viable prospective nuclear reactions have not been identified. Anything that produces energy primarily from positron emission is not viable due to the large annihilation energy. Also, positron annihilation energies were looked for but not found.


Do you know of any process that releases gammas or high energy x rays but not heat directly?

That is somewhat of an inconsistent condition. If the energy output is in the form of high energy photons then it produces heat. If the energy is in the form of 1 MeV photons or more, then my calculations (caveat: I make lots of mistakes) indicate it is not only readily observable but dangerous with 2 cm or 5 cm of lead. The converse is not inconsistent. There are many theories, including mine which provide logical reasons why the photonic energy from LENR is in the form of EUV or soft x-rays, which will only be observed as heat in normal conditions. Low energy alphas or protons would produce heat and be difficult to detect.


You answers to these simple questions would be most appreciated.

Dave

Simple but somewhat time consuming to answer. I am going to bail out on conversation for a few days.

Best regards,

Horace Heffner
http://www.mtaonline.net/~hheffner/




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