摘要:

We present the results of measurements of the gamma‐ray and neutron background in the Gran Sasso Laboratory, which were performed by a novel coincidence spectrometer allowing neutron identification by means of two different stages of pulse‐amplitude analysis.

ISSN:0094-243X    

DOI:10.1063/1.40709

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

The first preliminary results on the neutron emission from a D2‐Ti system by means of a neutron detector using the double scattering technique are reported. The Ti system was observed during the absorption of the deuterium in a cooling phase; analogous measurements with H2replacing the D2were performed in order to use them as blank.

ISSN:0094-243X    

DOI:10.1063/1.40692

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

Comments are presented on the experiment conducted at Yale in August 1989 to search for neutron emission from D2‐gas loaded metals. (AIP)

ISSN:0094-243X    

DOI:10.1063/1.40697

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

We have conducted a search for neutron emission from cold fusion systems of the electrochemical type and, to a lesser extent, the high‐pressure gas cell type. Using a high‐efficiency well counter and an NE 213 scintillator, the experiments were conducted on the earth’s surface and in a shielded cave approximately 50 ft underground. After approximately 6500 h of counting time, we have obtained no evidence for cold fusion processes leading to neutron production. However, we have observed all three types of neutron data that have been presented as evidence for cold fusion: large positive fluctuations in the neutron counting rate, weak peaks near 2.5 MeV in the neutron energy spectrum, and bursts of up to 140 neutrons in 500‐&mgr;s intervals. The data were obtained under circumstances that clearly show our results to be data encountered as a part of the naturally occurring neutron background, which is due primarily to cosmic rays. Thus, observing these types of data does not, of itself, provide evidence for the existence of cold fusion processes. Artifacts in the data that were due to counter misbehavior were also observed to lead to long‐term ‘‘neutron bursts’’ whose time duration varied from several hours to several days. We conclude that any experiments which attempt to observed neutron emission must include strong steps to ensure that the experiments deal adequately with both cosmic‐ray processes and counter misbehavior.

ISSN:0094-243X    

DOI:10.1063/1.40664

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

Several experiments were performed at the INFN Underground Gran Sasso Laboratory (Italy) in order to detect nuclear signals, if any, coming from deuterated materials in the framework of so called ‘‘Cold Fusion.’’ We followed three, quite different, lines of experimental researches.In the first set of experiments we used electrolytic solutions of heavy water and 0.1 M LiOH with some addition of gaseous CO2, using as cathode a rod of pure Pd or Ti alloys and as anode a Pt net. We detected several intense bursts of gamma rays, lasting up to 15 minutes of duration time, with energy less than 300 KeV.In the second set of experiments we used pellets of sintered High Temperature Superconductors (HTSC) that underwent deuteration by high pressure (∼30 Bar) and temperature (∼370 K) gas loading procedure. The deuterated samples were several times cycled down to liquid nitrogen temperature and we detected by two independent3He moderated neutron detectors (1.2% total efficiency), sporadic emission of signals mainly during these thermal cycles.Later on similar tests were performed independently by S. E. Jones and collaborators (Provo Univ., Utah) in a deep underground mine and a very intense and short neutron burst was detected by 16 independent3He moderated neutron detectors (32% efficiency).In the third set of experiments some additional tests were performed using a low activity Am‐Be neutron source, in order to study possible phenomena of enhanced neutron emission by radiation stimulation in these HTSC deuterated compounds. We detected excess counts of 2 static standard deviations, pointing to increased D‐D cross section due to the effect of ceramic lattice.

ISSN:0094-243X    

DOI:10.1063/1.40681

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

Two high‐efficiency neutron detectors, a neutron‐burst detector and a spectrometer was designed and built at Brigham Young University. (AIP)

ISSN:0094-243X    

DOI:10.1063/1.40711

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

The emission of neutrons from a titanium‐deuterium gas system has been detected by us in experiments performed in the Spring of 1989. One of the most striking features was the structure in bursts (duration of about 100 &mgr;s) of the neutron emission. Using a detection system proposed by H. Menlove, suitable to analyze the structure in bursts of the emission, a preliminary set of measurements has been performed with satisfactory results. A better tailored detector is now in use, and measurements in a low neutron background are being started. The first data about background and calibration measurements for this experiment will be reported.

ISSN:0094-243X    

DOI:10.1063/1.40712

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

We describe in this communication experiments accomplished since September 1989 with Ti and Pd cathodes. In several runs nuclear products above background levels were detected. Results together with experimental details are discussed. The quality of nuclear detection is considered, by describing the calibration procedures as well as spurious factors that can lead to misleading interpretations.

ISSN:0094-243X    

DOI:10.1063/1.40713

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

Neutron emission from a palladium target electrolytically loaded by deuterium was recorded. The emission was composed of several short (≤1 min) bursts each containing of the order of 10–102neutrons superimposed on a weak (∼1 min−1) sporadic single neutron radiation. Two events with time correlation within 10 &mgr;s of proton, acoustic and radio emission were observed. The excess of tritium in the gas desorbed from the palladium target was found.

ISSN:0094-243X    

DOI:10.1063/1.40714

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

42 events of correlated neutron and acoustic emissions from the electrolytically deuterized palladium target were recorded in the course of the experiment which had been fulfilled at the Baksan underground low background Laboratory. The expected number of false correlations was estimated to be close to 5 events. The results obtained confirm the predictions of the acceleration model which connects the cold fusion process with fracturing a deuterized matter.

ISSN:0094-243X    

DOI:10.1063/1.40715

出版商:AIP    

年代:1991

数据来源: AIP