Underground work is practically a standard for use of energy
discriminating neutron counters, due to the very low neutron flux
from CF experiments. This low flux is why integrating plastic
counters are useful. The following were taken from Dieter Britz's
abstracts:
Zhu R, Wang X, Lu F, Ding D, He J, Liu H, Jiang J, Chen G, Yuan Y,
Yang L,
Chen Z, Menlove HO;
Fusion Technol. 20 (1991) 349--353
"Measurement of neutron burst production in thermal cycle of D2 absorbed
titanium chips".
** Experimental, Ti, gas phase, neutrons, res+
A Chino-USA effort to find neutrons in a Ti/D2 gas system with thermal
cycling - the "Italian" mode. The experiment was done 580 m
underground to
minimise cosmic influx. Humidity had to be avoided, to avoid fake
neutron
bursts from the (3)He detectors (18 of them). The setup was not
sensitive to
mechanical knocks. H2 dummy batches were run to eliminate other
artifacts.
There were 10 D2 batches and only 3 of these showed no neutron
emissions. The
others showed neutron bursts of up to 535 from a burst. The burst
intensity
was up to 2 orders of magnitude above the carefully monitored
background. The
bursts occur during the first one or two thermal cycles, between -100
degC and
room temperature; thereafter, the Ti seems to be inactive. They could be
reactivated by vacuum degassing and reloading but the activity was
lower. The
controls with H2 ruled out interference effects. 021991|111991
#
Aberdam D, Avenier M, Bagieu G, Bouchez J, Cavaignac JF, Collot J,
Durand R,
Faure R, Favier J, Kajfasz E, Koang DH, Lefievre B, Lesquoy E,
Pessard H,
Rouault A, Senateur JP, Stutz A, Weiss F;
Phys. Rev. Lett. 65 (1990) 1196--1199.
"Limits on neutron emission following deuterium absorption into
palladium and
titanium".
** Experimental, neutron detector, res-
This group has a new type of neutron detector which will detect any
neutron
with an energy > 1MeV and allows discrimination against Compton electron
background. This was used in an underground lab, where the neutron
background
was a low 1.7 n/day. Both electrochemical and pressurization cold fusion
experiments were done, closely following the example of FPH, Jones+
and De
Ninno+. In some of the electrochemical runs, the currents were abruptly
changed several times, to test for dynamical effects. Dynamical
effects were
also attempted with the gas absorption runs (up to 60 bars), by
temperature
changes between that of liquid N2 and 950 degC, both fast and
slowly. In all
cases, something like 1E-26 n/pair/s was measured as an upper limit,
or a
factor of 100 below Jones et al's results. No bursts were observed.
121989|091990
#
#
Carpenter JM;
Nature 338 (1989) 711.
"Cold fusion: what's going on?"
** Discussion, polemic
JMC was a referee of Jones+'s paper, and was invited by the editor to
comment
publically on the paper. He warns that cosmic ray neutrons must be
eliminated
from neutron measurements, or at least recognised. Their intensity is
about
the same as that reported for CNF, and there can be peaks at the
energy 2.45
MeV. Suggests that going underground by two or three metres should
reduce the
cosmic ray problem by an order of magnitude. ?|041989
#
Celani F, Spallone A, Pace S, Polichetti B, Saggese A, Liberatori L,
Di Stefano V, Marini P;
Fusion Technol. 17 (1990) 718--724
"Further measurements on electrolytic cold fusion with D2O and
palladium at
Gran Sasso Laboratory".
** Experimental, electrolysis, Pd, neutron, gamma, res+
Electrolysis experiments with Pd were performed in the low-background
underground lab, measuring gamma and neutron radiation. The diagram
shows that
two (3)He detectors, two NaI detectors and a plastic scintillator
were used.
It appears that the electrolyte was 0.1M LiOH in heavy water.
Electrolysis
current density was 60 mA/cm**2, at hyperpure, vacuum-annealed Pd.
There were
some definite gamma events on all detectors, calculating out as up to
1E-19
fusions/pair/s. These gamma events were unaccompanied by neutron
events, so
the authors conclude that an aneutronic process is taking place. They
also
state that it was not possible to exclude fractoemission effects.
Future work
is planned. 121989|071990
#
#
Chiba M, Shirakawa T, Fujii M, Ikebe T, Yamaoka S, Sueki K, Nakahara H,
Hirose T;
Nuovo Cimento 108 A (1995) 1277--1280
"Measurement of neutron emission from LiNbO3 fracture process in D2
and H2
atmosphere."
** Experimental, fractofusion, superconductivity, neutrons, res+
This aims to confirm the results of Russian work, in which neutron
emission
was observed at the Curie temperature Tc during temperature scanning of
superconducting ceramics, as well as earlier work by the present team
on the
title substance. The Russian workers ascribe the emissions to
mechanical
effects due to phase transitions. The title substance was
mechanically crushed
in a steel vibromill in an atmosphere of H2 or D2 while monitoring for
neutrons, using 10 3He counters divided into 5 sets, placed closely
around the
sample. Experiments were conducted in an underground environment
with a low
background count of 9.3 +- 0.1 c/h. For H2 at 101 kPa, the count rate
was 8.7
+- 1.2 c/h, or the same as the background, but for a D2 atmosphere (same
pressure) it was 10.3 +- 0.7 c/h, or an excess of 1.0 +- 0.2 c/h,
regarded as
significantly higher than the background. There is some speculation
about high
voltages generated by the mechanical action, possibly up to 10 keV, and
acceleration of deuterons across cracks. Rough calculations agree
with the
observations. Thus, mechano-nuclear fusion can be added to the other
fusion
techniques, conclude the authors. 061995|101995
#
#
Ewing RI, Butler MA, Schirber JE, Ginley DS;
Fusion Technol. 16 (1989) 404--407
"Negative results and positive artifacts observed in a comprehensive
search
for neutrons from 'cold fusion'".
** Experimental, electrolysis, gas phase, Pd, Ti, res-
A search for neutrons using both electrochemical and gas pressure
loading was
conducted in an underground lab using 3 highly sensitive neutron
detectors.
Any n emission would be detected simultaneously in all 3 in a known
proportion. Individual detectors occasionally emitted groups of counts
mimicking both continuous and burst emission. These were identified as
artifacts. The use of simultaneous detection on several detectors is
thus
essential for exclusion of such artifacts. 071989|111989
#
Ewing RI, Butler MA, Ginley DS, Schirber JE;
IEEE Trans. Nucl. Sci. 37 (1990) 1165--1170
"A sensitive multi-detector neutron counter used to monitor 'cold
fusion'
experiments in an underground laboratory: negative results and positive
artifacts".
** Experimental, neutron detector design
The team has reported their results in two other papers, and here
describes
the neutron detector used. It consisted of three independent
detectors, each
one comprising 11 gas proportional counters; thermal neutrons were
detected
via the (3)He (n,p) reaction. The laboratory was situated underground
in a
low-background environment, down by a factor of 700 below that at the
surface.
A total of 339 counting hours produced the same number of counts as a
control.
There was a single coincidence peak (counts on all three), but this was
statistically not significant.
There were a number of false signals from single detectors, not
shared by the
others. These artifacts, which have a number of causes, might confuse
a cold
fusion experimenter using a single detector. From the measured
neutron flux,
an upper limit of 66 neutrons per hour can be inferred. ?|061990
#
Ewing RI;
J. Fusion Energy 9 (1990) 473.
"High-sensitivity neutron detectors used at Sandia National
Laboratories to
monitor and diagnose 'cold fusion' experiments: negative results".
** Experimental, electrolysis, gas phase, Pd, Ti, neutrons, res-
A multidisciplinary group has tried out every type of cold fusion
experiment
known to them, for which positive results have been claimed, in an
underground
site with low background neutron count (10 c/h) and using high
efficiency
(9-10%) detectors. This counter can detect < 100 c/h and bursts of < 35
counts. Nothing was detected. The counter has 22 (3)He proportional
counter
tubes embedded in polythene, connected so as to form three
independent neutron
detectors. One detector at a time did show random signal artifacts, but
coincidence on all three eliminated these. Spurious counts can arise
from
acoustic disturbances, electrical discharges across insulators,
electronic
noise and cosmic showers. Ewin1990b ?|121990
#
#
Golubnichii PI, Kuz'minov VV, Merzon GI, Pritychenko BV, Filonenko AD,
Tsarev VA, Tsarik AA;
JETP Lett. 53 (1991) 122--125
{Orig. in: Pis'ma Zh. Eksp. Teor. Fiz. 53 (1991) 115 (in Russian)}
"Correlated neutron and acoustic emission from a deuterium-saturated
palladium
target".
** Experimental, fracto, Pd, neutrons, res+
What the fractofusion school of thought has been waiting for; are the
cracks
sources of neutrons? Experiments were done under low background
conditions,
underground. The Pd was electrolytically saturated with deuterium.
Neutrons
were moderated in paraffin and detected with an array of 10 SNM-18
counters,
with an overall efficiency of 10%. SOund was measured with a ceramic
piezoelectric device. Correlation measurements were carried out for
3.5 h.
There were 42 correlated events (with a time shift, due largely to
the finite
propagation of the acoustic signal), while 6 are expected if they
were random.
So the results appear to support the fractofusion model. 121990|011991
#
Golubnichii PI, Merzon GI, Filonenko AD, Tsarev VA, Tsarik AS;
Sov. Phys. - Lebedev Inst. Rep. (1990)(8) 31--35
{Orig. in: Kratk. Soobshch. Fiz. (1990)(8) 26}
"Correlation between nuclear, acoustic, and electromagnetic emissions
during
the electrolytic saturation of palladium with deuterium".
** Experimental, electrolysis, Pd, acoustics, nuclear, em, res+
Four series of measurements were carried out, three of them
electrolysis at a
Pd plate at the bottom of a cell, in 0.1M LiClO4 in D2O; a microphone
was
soldered to the palladium, a CdI crystal underneath it to catch
nuclear events
and an electromagnetic probe to catch signals up to 1MHz in frequency.
Electrolysis was continued (at 1A) for 3.5, 3.5 and 2 hours. In the
fourth
experiment, a D-charged Pd cathode was heated in a vacuum chamber to
drive out
the deuterium, while also monitoring the three kinds of emissions. The
acoustic probe came loose, however. All in all, two events were seen,
in which
the three signals coincided, during the electrolysis runs; none
during the
desorption run. Going by the frequencies of events of the individual
signals,
the expected number of such coincidences was 1E-07, so that 2 might
be a large
number. The authors admit to the weakness of these statistics and
agree that
further work is needed. They did, however, write another paper to
explain
these results (p.16/15, same journal issue). 051990|?
#
#
Kocsis M, Nyikos L, Szentpetery I, Horvath D, Kecskemeti J, Lovas A,
Pajkossy T, Pocs L;
J. Radioanal. Nucl. Chem., Lett. 145 (1990) 327--337
"Search for neutrons from cold nuclear fusion".
** Experimental, electrolysis, gas phase, Pd, Ti, neutrons, res+
The authors note that of those cold fusion studies in which neutron
emission was measured, few have been successful; they, too, wanted to
have a
go at it. An FPH-type electrochemical cell was used with Pd, as well
as a tube
filled with Ti chips and D2 gas. A triple (3)He proportional counter
was used
for neutron detection; its calibrated efficiency was 6.3%. A lengthy
background measurement showed some "statistically significant"
excursions
above the mean of 0.06 c/s, possibly due to barometric variations in the
cosmic background, and a well distinguished neutron peak. A
subsequent 9-day
electrolysis showed nothing above this background. The experiment was
then
moved into an underground tunnel at a depth of 30 m in limestone. Now
the mean
background was 0.003 c/s but with occasional "huge burstlike
excursions" due
to electrical disturbances in the power network. Some filtering etc
resulted
in a stable background of about 0.002 c/s. During two electrolysis
runs - one
continuous, the other with periodic current switching -, as well as
the Ti/D2
run, no neutron emission above the background was observed. The
authors note
that upon switching off the electrolysis current, violent bubbling
occurred
at the Pd cathode, i.e. that the Pd was saturated with deuterium.
061990|071990
#
#
Lipson AG, Lyakhov BF, Roussetski AS, Akimoto T, Mizuno T, Asami N,
Shimada R,
Miyashita S, Takahashi A;
Fusion Technol. 38 (2000) 238--252
"Evidence for low-intensity D-D reaction as a result of exothermic
deuterium
desorption from Au/Pd/PdO:D heterostructure".
** Experimental, Pd heterostructure, electrolysis, neutrons, cps, res+
The Russian team visited a Japanese lab and an experiment was done,
using the
Au/Pd/PdO layered electrode in an electrolyte of either 1M NaOD in
D2O or NaOH
in H2O.Electrolysis time varied from 5 min for thin foil up to 90 min
for
thicker foil. Loadings up to 0.7 were achieved. Neutrons were
measured by two
NE-213 detectors on opposite sides of the cell with appropriate
electronics
to filter out gamma rays, in a low-background underground
environment. For
charged particles, SSB detectors were used. Results were very low
neutron
emissions, indicating fusion rates below the Jones level at 10^{-23} /
s/dd.
Even less cp emission was detected but can be explained by absorption
within
the foils. Thus, both measurements confirm cold fusion. 071999|092000
#
#
Menlove HO, Fowler MM, Garcia E, Miller MC, Paciotti MA, Ryan RR,
Jones SE;
J. Fusion Energy 9 (1990) 495--506
"Measurement of neutron emission from Ti and Pd in pressurized D2 gas
and D2O
electrolysis cells".
** Experimental, Ti, Pd, V, gas phase, neutrons, fracto, res+
LANL and Brigham Young get together to measure neutron bursts and
randoms
from a variety of sample types, such as D2 gas mixed with Pd and Ti
chips,
sponge, crystals and powder, as well as electrolysis in D2O at
cathodes of Ti,
Pd and V. Four separate neutron detectors were used, all based on (3)
He tubes.
These were placed 1-2 m from each other, in an underground, low-
background
lab. There is a lot of detail on the neutron detection technique,
which can
exclude common noise sources such as electrical noise, rf
interference and
cosmic showers, and uses correlation to distinguish between real neutron
bursts and artifacts. Also, there was an acoustical detector attached
to the
sample bottle, to detect cracking of the Ti samples.
Control runs had tubes of Ti in air, or cells without electrodes,
or cells
with H2O instead of D2O. The electrolytes were the Jones+ soup as
well as
others. Everything is tabulated for the reader.
Neutron bursts were detected from Ti in D2, and also from Ti in a
50:50 mix
of D2:H2 (to test for p-d fusion). No bursts from dummy controls.
Random-neutron counts were also seen from Ti+D2, but not from
controls. The
electrolysis runs showed some 3-sigma random emissions and one showed
bursts,
going on for some days. So, out of 42 carefully done experiments, 14
produced
significant neutron emissions, mostly in the form of bursts, by up to
two
orders of magnitude above the background. The bursts are consistent
with the
fracto-fusion idea, although no bursts correlated with cracking
noises. The
random emissions cannot be the sum of small bursts, so neutrons are
emitted by
two separate processes, maybe. The common denominator between them is
nonequilibrium. Future work is planned, to characterise the materials
used and
to improve the detection to the point where energy spectra can be
obtained.
Menl1990b ?|121990
#
#
Menlove HO, Miller MC;
Nucl. Instr. Methods Phys. Res. A 299 (1990) 10--16
"Neutron-burst detectors for cold-fusion experiments".
** Design, neutron detector
This describes the neutron detector built at LANL, and details some
of the
design considerations. The job is to cope with the intermittent
nature and low
intensity of the neutrons, and with short bursts without losing
information.
The high-efficiency detectors used by Menlove et al are based on (3)
He gas
tubes in a CH2 moderator. An inner ring of nine (3)He tubes is
surrounded by
an outer one of 42 tubes. The inner ring is unmoderated and is more
sensitive
to lower-energy neutrons, while the moderated outer ring responds to
higher-
energies. Bursts are handled by time-spread them by thermalisation in
the CH2
moderator. The detectors have been used in cold fusion experiments
(mostly
reported elsewhere) in an underground laboratory with low background,
and
worked well. ?|121990
#
#
Schirber JE, Butler MA, Ginley DS, Ewing RI;
Fusion Technol. 16 (1989) 397--400
"Search for cold fusion in high-pressure deuterium-loaded titanium and
palladium metal and deuteride".
** Experimental, Ti, Pd, gas phase, neutrons, res-
Various Ti and Pd samples were put under high-pressure (>=2.4 kbar) D2
and temperature cycling. Underground high-sensitivity (9.2%) neutron
monitoring (background: 10 counts/h) showed nothing in excess of
background.
061989|111989
#
#
Shibata T, Imamura M, Shibata S, Uwamino Y, Ohkubo T, Satoh S,
Yamakoshi K,
Oyama N, Ohsaka T, Yamamoto N, Hatozaki O, Niimura N;
Nucl. Instrum. Methods Phys. Res. A316 (1992) 337--342
"A low background neutron measuring system and its application to the
detection of neutrons produced by the D2O electrolysis".
** Experimental, neutron detector design, res-
For cold fusion experiments as well as others, it is important to be
able
to measure low-level neutron emission and distinguish it from the
background,
largely due to cosmic rays and natural radioactivity. A suitable
system was
developed and tested in an underground lab, on a cold fusion
electrolysis. The
choice was two spherical (3)He detectors at 10 atm pressure, 5 cm
diameter and
buried in polyethylene moderator, with another (background) detector in
another part of the moderator block. The block was shielded by
paraffin blocks
containing boric acid. Counts and discriminator counts were stored on
a floppy
disk. The lab's temperature was kept constant at about 23 C, humidity
at 65%.
An air flow prevented radon accumulation. The detector's efficiency
was 4% or
so, and the background was 1/20 that at sea level, depending on the
material
placed into the cell (i.e. its atomic mass). For pure Cu, it was about
0.3E-04 n/s/mol. A number of Pd cathodes were tried for D2O
electrolysis, and
the measured neutron emission did not deviate, either in intensity or in
count frequency distribution, from the background. There was also
analysis of
the electrolyte for tritium before and after, with none found. 081991|?
#
#
Shirakawa T, Chiba M, Fujii M, Sueki K, Miyamoto S, Nakamitu Y,
Toriumi H,
Uehara T, Miura H, Watanabe T, Fukushima K, Hirose T, Seimiya T,
Nakahara H;
Chem. Lett. (1993) 897--900
"A neutron emission from lithium niobate fracture".
** Experimental, fracto, Nb, neutrons, res-
When an ionic crystal is crushed, fracture separates charges on the new
surfaces, leading to high fields, which may accelerate deuterons if
present.
Here, rather than wait for cracking, the team crushed single crystals of
lithium niobate in a vibromill in the presence of D2 gas, and
monitored the
neutrons emitted with a ring of 10 3He proportional counters, a
paraffin block
thermalising the neutrons; efficiency 2.6%. This was carried out at an
underground, low cosmic background location (100 m water depth
equivalent, 7.6
neutrons/h during 132 h). Crushing was maintained for 1 h at a time.
12 such
runs were summed, and the neutron spectrum in excess over the
background is
shown. It is close to zero in the region of channels >1600, but in clear
excess (34.8 neutrons) in the region below this. The Fig. states that
channel
1400 lies at 760 keV thermalised neutrons. There was no observable
effect of
D2 pressure (1.1 to 101 kPa), nor of the addition of LiD. No excess
neutrons
were found when Ti or Pd metal was crushed under D2O, to emulate the
Russian
work (Klyuev et al), which is thus not confirmed. 021993|051993
#
#
Tomas P, Blagus S, Bogovac M, Hodko D, Krcmar M, Miljanic D, Pravdic V,
Rendic D, Vajic M, Vukovic M;
Fizika (Zagreb) 21 (1989) 209--214
"Deuterium nuclear fusion in metals at room temperature".
** Experimental, Pt, electrolysis, neutrons, surface analysis, res-
Starts with an interesting historical introduction on cosmic ray mesons
and discussions of 1947 and thereafter.
This team tried to reproduce the FPH electrolysis experiment. X-ray
fluorescence after long electrolysis showed Pt deposition of the Pd. A
(6)Li-glass scintillation (NE 912) counter was used to used to detect
neutrons. The experiment took place in an underground lab, and no
neutrons
above the low background were seen. The authors promise results from
tritium
analysis of both the electrolyte and palladium, as well as from proton
measurements, to be done. 051989|061989
#
Best regards,
Horace Heffner
http://www.mtaonline.net/~hheffner/
