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Cold Fusion experiments and Bariloche - Argentina
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Path: santra!tut!draken!kth!mcvax!uunet!lll-winken!ames!apple!motcsd!hpda!hpcupt1!vcate
From: vcate@hpcupt1.HP.COM (Vincent Cate)
Newsgroups: sci.physics.fusion
Subject: Cold Fusion experiments at Bariloche - Argentina
Message-ID: <-286009998@hpcupt1.HP.COM>
Date: 28 Jun 89 21:37:13 GMT
Organization: Hewlett Packard, Cupertino
Lines: 449
Here is another paper. It will be sf.ascii in the archive.
The Santhanam paper will be ks.ascii. I will post the list
of papers in the archive after I send this off.
-- Vince
-------------------------------------------------------------------
Date: Wed, 28 Jun 89 13:36 MST
From: "Sergio Felicelli. University of Arizona. Tucson."
<SERGIO@rvax.ccit.arizona.edu>
Subject: from Argentina through Arizona
To: vincent.cate@sam.cs.cmu.edu
X-Vms-To: IN%"vincent.cate@sam.cs.cmu.edu"
Dr. Vincent Cate
I'm sending a report of work done here at Bariloche, Argentina about CF.
We have suscribed to PHYSICS and last week we have sent this report to
Physics-Request, but until now has not been distributed.
As surely I have made some mistakes in sending the report, would you mind
to tell me how can I do that, because people involved in CF experiments
would like to receive opinions about their work.
Though this e-mail is being sent to you from Arizona, it is currently
written in Argentina.
The reason: we have no yet a Bitnet node here.
Last question: how can I subscribe to Usenet alt.fusion newsgroup from
Arizona?
Thanks for your help and feel free of redistribute the report enclosed if
you like.
Erwin G. Galdoz
e-mail: sergio@arizrvax.bitnet
____________________________________________________________________
Cold Fusion experiments at Bariloche - Argentina
------------------------------------------------
This report summarizes the results of experiments carried out
at Centro Atomico Bariloche (Argentina) from the beginning of
April 1989. They are based on neutron measurements performed
on both electrochemical cells and gas injection systems.
During the last two decades, neutron transmission and diffrac-
tion experiments have been conducted at our Neutron Physics
Division, most of them over the thermal neutron energy range.
We therefore decided to exploit our previous experience in
measuring thermal neutrons using 3He detectors, in order to
devise a high efficiency detection system for that energy range.
We started our work on electrochemical cells in collaboration
with scientists from the Thermohydraulics Division, as it was
this kind of system on which the first positive results were
reported.
Over a period of more than two weeks we performed experiments
according to the classical 'stationary' method (as far as the
electrolytic current is concerned), with an essentially null
result.
In order to more effectively discriminate the effect of the
background in our measurements, we introduced another dimension
- time - in the form of a pulsed current through the cell. The
basic concept behind this methodology is that this kind of
measurements should provide essentially 'self normalized' data,
bearing in mind the difference in time scales of the current
pulses and background fluctuations.
Our first positive results were presented on May 2, 1989, as
Contribution # 22 to 'Special Session on Cold Fusion' during
the Spring Meeting of the APS (Baltimore):
==========================================
DYNAMIC RESPONSE OF THERMAL NEUTRON MEASUREMENTS IN
ELECTROCHEMICALLY PRODUCED COLD FUSION SUBJECT TO
PULSED CURRENT
J.R. Granada, J. Converti, R.E. Mayer, G. Guido,
P.C. Florido, N.E. Patino, L. Sobehart, S. Gomez and
A. Larreteguy
Centro Atomico Bariloche and Instituto Balseiro,
Comision Nacional de Energia Atomica and
Universidad Nacional de Cuyo
8400 S.C. de Bariloche, Rio Negro
ARGENTINA
----------
ABSTRACT
The present work shows the results of measurements
performed on electrolytic cells using a high efficiency
(22%) neutron detection system in combination with a
procedure involving a non-stationary current through the
cell's circuit.
Cold fusion was produced in electrolytic cells
containing LiH dissolved in heavy water with a Palladium
cathode. The dynamic response to low frequency current
pulses was measured. Characteristic patterns showing one or
two bumps were obtained in a repeatable fashion. These
patterns are strongly dependent on the previous charging
history of the cathode.
The technique employed seems to be very convenient as a
research tool for a systematic study of the different
variables governing the phenomenon.
----------
The exciting possibility of inducing the cold fusion of
deuterium nuclei has been supported in recent years by
studies on muonic D2 molecules, and very recently enhanced
by evidences on the feasibility of using electrochemical
methods.
In order to experimentally explore the latter
mechanism, we have performed measurements on electrolytic
cells using a high efficiency neutron detection system in
combination with a procedure involving a non-stationary
current through the cell's circuit.
Electrolysis was produced in a cylindrical pyrex cell
of 39 mm internal diameter and 120 mm height. The anode
consisted of Platinum foils of 20 x 45 mm2 located at both
sides of a 27 x 42 x 1 mm3 Palladium cathode. The latter was
cut from a 99.9% pure material, cleaned and degassed in
vacuum at 160 C during 90 minutes. It was supported by a
stainless steel holder and completely submerged in the
electrolyte. A cathode consisting of 99.99% pure Palladium
wire 0.5 mm in diameter and 120 mm long was also used. The
electrolyte consisted of 0.1 M Lithium hydride in 99.66
weight percent D2O and 0.34 percent H2O.
Based on our previous experience in thermal neutron
work, we decided to look for those neutrons coming up from
the cell position which may arrive at the detectors after
slowing down their energy in a moderating medium. To
establish the design parameters and optimization of the
complete detection arrangement, neutronic calculations were
performed on the basis of a one-dimensional cylindrical
geometry, using the code AMPX-IIA fed with standard cross
section libraries. Having defined all the regions and
materials involved, the design criterium adopted was the
attainment of a maximum counting rate in the neutron
detectors, leaving as optimization parameters the size of
the moderator and reflector regions, together with the
number of detectors (3He, 10 atm. filling pressure, 1"
diameter, 6" active length). The configuration adopted
consists of an arrangement of 18 tubes, with a calculated
efficiency of 20% which includes the solid angles subtended
by them. This calculation was experimentally validated by
placing natural uranium pellets (conveniently packed) of
known activity at the site of the electrolytic cell yielding
an efficiency of 22% for the whole detection system.
The detectors were bunched into three clusters of six
tubes each, and the signals in the three acquisition lines
strongly discriminated in pulse height before being
channeled to an anti-coincidence logic to reject
simultaneous pulses (within 2 microseconds) coming from
different detector clusters.
The cell was kept for long periods (few days) under a
low current, typically 150 mA for the Pd sheet and 50 mA for
the wire, while the corresponding voltages were below
4 V. After this 'charging' period, the experiments were
carried out in a pulsed fashion: each cycle consisted of a
90 sec. period at 6 V and 64 sec. at open circuit, and a
typical run contained 20-30 of such cycles. The counts were
accumulated into 512 channels (0.3 sec. width) of a
multichannel scaler, triggered simultaneously with the
beginning of each cycle. After this run, the procedure was
repeated with a dummy cell to measure the background; this
cell was identical to the one described previously, except
that the electrolyte was prepared with H2O.
Through our measurements we have observed several well
defined features. Figure 1 shows a typical time spectrum of
observed neutron counts for a sheet cathode that had been
activated for 20 hours. Two bumps are clearly visible, about
30% over the background level indicated by the dashed line.
This structure repeats itself for cathodes with similar
charging history, either sheet or wire. These features seem
to indicate an increase in the fusion rate associated with
the enhanced mobility of deuterons in and out of the Pd
induced by the current pulse.
Figure 2 shows the results of increased neutron
production during the zero current period of the cycle, for
a cathode charged at 250 mA during 75 minutes. In this case,
the absence of a bump during the first part of the cycle
seems to correlate with the reduced capability of the
deuterons to penetrate into the saturated (at least
superficially) cathode.
The above results suggest that an increased fusion rate
can be achieved under strong non-equilibrium conditions.
Prolongued cycling tends to discharge the cathode. This
is indicated by the results of Fig. 3, in which the squares
correspond to the spectrum accumulated during the first five
cycles of a run with a 75 sec. half period for a cathode in
the same initial conditions as in Fig. 1. The X symbols
correspond to the last five cycles of a total of twenty.
This latter spectrum shows an almost complete lack of
structure and a reduction in the total number of counts,
suggesting that the neutron producing process switched-off
leaving a counting level which can be considered as the
proper background for this measurement.
Based on the efficiency of our detection system we
infer from our results a rate of ca. 0.3 fusions per second,
consistent with reported negative results by other workers
using less efficient detection devices when cold worked
cathodes are used.
The features described in Figs. 1, 2 and 3 have been
consistently verified in more than twenty different
experiments performed over a period of a week. Equivalent
measurements alternatively done using H2O based electrolyte
show spectra like the one presented in Fig. 4, in which no
definite structure can be observed. A best fit study of the
light water spectra obtained for a number of runs made under
the same conditions gives a horizontal line as the most
probable curve (98 % confidence level).
In conclusion, we have established a strong correlation
between the neutron counting rate and the cycling of the
current during the electrolysis of D2O. This suggests that
this technique is very adequate to discriminate the low
counting rate associated with the induced cold fusion
process.
We wish to thank D. Delmastro, M. Salvatore and V.
Ishida for their collaboration in carrying out the
measurements through long days and longer nights; and to V.
H. Gillette, J. Dawidowski, G. Lantschner, M. Abbate and M.
M. Sbaffoni for their help and encouragement; and also to
the technicians L. Capararo, R. Bravo, D. Mateos and M.
Enevoldsen through whose efforts all this work could be
started in a very short time.
FIGURE CAPTIONS
Fig. 1. Typical time spectrum of observed neutron counts
for a sheet cathode activated for 20 hours. The
dashed horizontal line indicates the background
level (see Fig. 4). The current pulse is
indicated at the bottom.
Fig. 2. Increased neutron counting rate during the zero
current period of the cycle for a cathode charged
at 250 mA during 75 minutes (see text).
Fig. 3. The squares correspond to the spectrum accumulated
during the first five cycles of a run with a 75
second period, whereas the X simbols correspond to
the last five cycles of a total of twenty (see text
for details).
Fig. 4. Background spectrum as obtained using H2O-based
electrolyte.
COUNTS/SEC
0.00 0.05 0.10 0.15 0.20 0.25 0.30
0 +---------+---------+---------+---------+---------+---------+
| | |
| |
| | ---O---
| | |
100 + | ---O---
| |
C | | | ---O---
H | |
A | | ---O---
N 200 + | |
N | | ---O---
E | |
L | | ---O---
| |
N 300 +----+ ---O---
U | |
M | ---O---
B |
E | | ---O---
R 400 +
| ---O---
| |
| ---O---
|
500 +---------+---------+---------+---------+---------+---------+
FIGURE 1
COUNTS/SEC
0.00 0.05 0.10 0.15 0.20 0.25 0.30
0 +---------+---------+---------+---------+---------+---------+
| | ---O---
| |
| | ---O---
| |
100 + |
| | ---O---
C | |
H | | ---O---
A | |
N 200 + |
N | | ---O---
E | |
L | |
| | ---O---
N 300 +----+
U |
M | ---O---
B |
E | ---O---
R 400 +
|
| ---O---
|
| ---O---
500 +---------+---------+---------+---------+---------+---------+
FIGURE 2
COUNTS/SEC
0.00 0.05 0.10 0.15 0.20 0.25 0.30
0 +---------+---------+---------+---------+---------+---------+
| | ------O---X--
| | O first five cycles
| | --------OX------- X last five cycles
| |
100 + | -------O--X----
| |
C | | X ----------O----------
H | |
A | | X ----------O----------
N 200 + |
N | | X --------O--------
E | |
L |----+ ------O--X--
|
N 300 + -------O-----X-
U |
M | X -----------O------------
B |
E | X ------------O------------
R 400 +
| ---X------O----------
|
| ---------O------X--
|
500 +---------+---------+---------+---------+---------+---------+
FIGURE 3
COUNTS/SEC
0.00 0.05 0.10 0.15 0.20 0.25 0.30
0 +---------+---------+---------+---------+---------+---------+
| | --O--
| |
| | --O--
| |
100 + | --O--
| |
C | | --O--
H | |
A | | --O--
N 200 + |
N | | --O--
E | |
L | | --O--
| |
N 300 +----+ --O--
U |
M | --O--
B |
E | --O--
R 400 +
| --O--
|
| --O--
|
500 +---------+---------+---------+---------+---------+---------+
FIGURE 4
===========================================
A few points must be stressed concerning the above paper. First of
all, at the time of its presentation our neutron detection system
was the most efficient and it still seems to be in that class after
the Santa Fe Conference.
The experimental device was mounted in a temperature controlled,
low humidity room and protected against mechanical vibrations. The
preamplifiers were polarized by batteries, while the HV source was
coupled to the power line through induction transformers.
The '2 of 3' logic proved to be extremely successful to prevent
the admittance of noise, as checked through the generation of acous-
tic vibrations, induction from the pulsed current wires and rf
signals. Of course, any of the above mentioned effects severely
affected each of our three independent lines before going through
that logic.
The pulse height spectra from our detection clusters were constant-
ly monitored and the only pulses accepted were those falling into
the peak(50%) of the characteristic 3He spectrum,in order to reduce
the effect of electronic (base line) noise.
As for the background measurements, they included runs with H2O
cells pulsed under the same conditions of the sample (D2O) cells;
also we performed measurements with sample cells with no pulsing
and without any cell inside the detection system.
Finally, during the last four weeks, we have repeated many times
the kind of features showed at Baltimore, using different kinds of
cathodes, current densities and periods. We are now in position to
fully confirm our early results, after achieving repetitivity in
the neutron response for cathodes with a similar charging history,
and performing all the checks we managed to imagine.
A final point concerning the fusion rate. It is clear for us that
in our experiments only the first atomic layers are affected, on
the basis of the time scale involved. Consequently, we can only
give a figure which represents a total, time averaged fusion rate,
and not normalized to the number of deuterons in the whole cathode.
A full paper containing our latest results is in preparation.
June 20, 1989
J. Rolando Granada
Centro Atomico Bariloche, 8400 S.C. de Bariloche (RN), ARGENTINA
FAX: +54 944 26262,
T: +54 944 26264
BITNET: sergio@arizrvax
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