H. Huck

A decommissioned LHC model magnet as an axion telescope

The 8.4 T, 10 m long transverse magnetic field of a twin aperture LHC bending magnet can be utilized as a macroscopic coherent solar axion-to-photon converter. Numerical calculations show that the integrated time of alignment with the Sun would be 33 days/yr with the magnet on a tracking table capable of

Short-term seasonal variability in 7Be wet deposition in a semiarid ecosystem of central Argentina.

5i in the vertical direction and

Search for an annual modulation of dark-matter signals with a germanium spectrometer at the Sierra Grande Laboratory

40i in the horizontal direction. The existing lower bound on the axion-to-photon coupling constant can be improved by a factor between 30 and 100 in 3 yr, i.e., g !cc [9]10~11 GeV~1 for axion masses [ 1 eV. This value falls within the existing open axion mass window. The same set-up can simultaneously search for low- and high-energy celestial axions, or axion-like particles, scanning the sky as the Earth rotates and orbits the Sun. ( 1999 Elsevier Science B.V. All rights reserved.

Cold dark matter identification: Diurnal modulation reexamined

The (7)Be wet deposition has been intensively investigated in a semiarid region at San Luis Province, Argentina. From November 2006 to May 2008, the (7)Be content in rainwater was determined in 58 individual rain events, randomly comprising more than 50% of all individual precipitations at the sampling period. (7)Be activity concentration in rainwater ranged from 0.7+/-0.3 Bq l(-1) to 3.2+/-0.7 Bq l(-1), with a mean value of 1.7 Bq l(-1) (sd=0.53 Bq l(-1)). No relationship was found between (7)Be content in rainwater and (a) rainfall amount, (b) precipitation intensity and (c) elapsed time between events. (7)Be ground deposition was found to be well correlated with rainfall amount (R=0.92). For the precipitation events considered, the (7)Be depositional fluxes ranged from 1.1 to 120 Bq m(-2), with a mean value of 32.7 Bq m(-2) (sd=29.9 Bq m(-2)). The annual depositional flux was estimated at 1140+/-120 Bq m(-2)y(-1). Assuming the same monthly deposition pattern and that the (7)Be content in soil decreases only through radioactive decay, the seasonal variation of (7)Be areal activity density in soil was estimated. Results of this investigation may contribute to a valuable characterization of (7)Be input in the explored semiarid ecosystem and its potential use as tracer of environmental processes.

CHARACTERISATION OF URANIUM(VI) SORPTION BY TWO ENVIRONMENTAL FUNGAL SPECIES USING GAMMA SPECTROMETRY

Abstract Results of a search for dark-matter induced annual modulation using 830.5 kg·days of data collected at the Sierra Grande underground laboratory with a germanium detector are presented. The analysis of the data does not show any indication of seasonal effects.

Solar Axion Experiments Using Coherent Primakoff Conversion in Single Crystals

We report on new estimates of the modulation expected in semiconductor detectors due to the eclipsing of dark matter particles in the Earth. We reevaluate the theoretical modulation significances and discuss the differences found with previous calculations. We find that a significantly larger statistics than previously estimated is needed to achieve the same level of sensitivity in the modulated signal. {copyright} {ital 1997} {ital The American Physical Society}

Examination of nuclear measurement conditions in cold fusion experiments

Abstract Uranium(VI) sorption by two highly uranium‐resistant air‐borne fungi in a low‐pH medium was measured by means of gamma spectrometry. Growth kinetics and stoichiometry of the two fungal species were also studied. Results show acceptable growth rates in synthetic medium with glucose and ammonia as carbon and nitrogen sources, respectively. Typical oxidative metabolism of carbohydrates was found. In vivo uptake of the radionuclide was negligible, but biosorption dry biomass presented a remarkable performance. The fungal strains showed potential for use in bioremediation.

Simulations of electron trajectories under the influence of an array of permanent magnets in a compact ion source

Abstract The results of a 1.94 kg · y pilot search for solar axions with an ultralow background Ge detector are reviewed. The detection method is based on Bragg-coherent Primakoff conversion of axions into photons when the momentum vectors of the axion and photon satisfy the Bragg condition. The theory of the experiment are presented for Ge and TeO 2 crystals. Future prospects of large volume experiments are discussed.

Searching for cold dark matter in the Southern Hemisphere. The experiment at Sierra Grande

The recent announcement of electrochemically induced nuclear fusion [1,2] has generated great interest and activity within the scientific community. In particular, there are several aspects related to the work of ref. 1 which are not fully understood and therefore deserve further investigation. One of them is the huge discrepancy between the amount of measured heat and the intensity of the supposedly accompanying nuclear radiation, namely neutrons and gamma rays. In view of the fact that the detection of nuclear radiation in the context of an electrochemical process is perhaps the most unequivocal fingerprint for the occurrence of fusion, we feel that a careful re-evaluation of the measurement conditions may be needed. In order to address this question, in the present paper we report on an attempt to observe this phenomenon and on the possible problems related to the detection techniques.

Assessment of 7Be content in precipitation in a South American semi-arid environment

Trajectories of electrons emitted from a filament in a discharge ion source are computer simulated in order to investigate their behavior under the influence of different magnetic fields. These calculations allowed a better understanding of the high efficiency obtained in a recently developed compact ion source.