F. Hasenbalg - Academia.edu (original) (raw)

Papers by F. Hasenbalg

Research paper thumbnail of Improvement of the phase transition boundary with cylindrical tin arrays

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2006

ABSTRACT One of the limitations of the ORPHEUS dark matter detector performances was the phase tr... more ABSTRACT One of the limitations of the ORPHEUS dark matter detector performances was the phase transition smearing of the spherical granules. This could be dramatically improved by the use of cylindrical tin arrays. Results of measurements with prototypes are shown.

Research paper thumbnail of First runs with the ORPHEUS dark matter detector

Nuclear Physics B - Proceedings Supplements, 2002

The ORPHEUS dark matter experiment is completed at our shallow depth laboratory in Bern (70 m.w.e... more The ORPHEUS dark matter experiment is completed at our shallow depth laboratory in Bern (70 m.w.e.). The detector relies on measuring the magnetic flux variation produced by weakly interacting massive particles (WIMPS) as they heat 30 pm diameter superheated superconducting tin granules (SSG) and induce superconducting-tonormal phase transitions. In au initial phase, 0.45 kg of tin granules in a segmented detector volume have been used. Preliminary results of the experiment will be reported. 0920-5632/02/S -see front matter 0

Research paper thumbnail of Experimental Search for Solar Axions via Coherent Primakoff Conversion in a Germanium Spectrometer

Physical Review Letters, 1998

Results are reported of an experimental search for the unique, rapidly varying temporal pattern o... more Results are reported of an experimental search for the unique, rapidly varying temporal pattern of solar axions coherently converting into photons via the Primakoff effect in a single crystal germanium detector. This conversion is predicted when axions are incident at a Bragg angle with a crystalline plane.

Research paper thumbnail of Neutrinoless double-β decay of76Ge: First results from the International Germanium Experiment (IGEX) with six isotopically enriched detectors

Physical Review C, 1999

... E. Garcia,3 D. González,3 F. Hasenbalg,1,† ... in several conference proceedings 5. The summe... more ... E. Garcia,3 D. González,3 F. Hasenbalg,1,† ... in several conference proceedings 5. The summed energy of the two electrons from the neu-trinoless double-decay 76Ge⇒76Se2e would appear as a peak at 2038.50.4 keV 6 superimposed on the back-ground spectrum. ...

Research paper thumbnail of Fusion cross sections in systems leading to Hf170 at near-barrier energies

Physical Review C, 1995

In an effort to study the effect of the entrance channel mass asymmetry on the fusion process at ... more In an effort to study the effect of the entrance channel mass asymmetry on the fusion process at near-barrier energies, we have measured the fusion cross section and its distribution according to the different evaporation residues for the 28Si+142Ce, 32S+138Ba, and 48Ti+122Sn systems. All these systems lead to the same compound nucleus 170Hf. The measurements were performed using a delayed

Research paper thumbnail of Orbiting features in the strongly damped binary decay of the Si28+ O16 system

Physical Review C, 1996

The binary decay into strongly damped fragments and the quasielastic reactions of the 28 Siϩ 16 O... more The binary decay into strongly damped fragments and the quasielastic reactions of the 28 Siϩ 16 O system were measured at E lab ϭ107.5 and 139.0 MeV in the angular range of 30°р c.m. р150°using kinematic coincidence. The loss in the binary decay cross section due to light particle evaporation by the highly excited fragments was evaluated. The Q-value-integrated angular distributions of the primary decay exhibit the 1/sin c.m. behavior at backward angles, indicating a long lifetime. Mass distributions and the 16 O/ 12 C ratio suggest a noncompound process for the reaction mechanism. Coupled-channels calculations, including a great number of channels populated in the reactions, yield good agreement with the experimental angular distributions. ͓S0556-2813͑96͒03605-9͔

Research paper thumbnail of Absence of anomalous entrance channel effects in sub-barrier heavy ion fusion

Research paper thumbnail of Cold dark matter identification: Diurnal modulation reexamined

Nuclear Physics B - Proceedings Supplements, 1999

We report on new estimates of the modulation expected in semiconductor detectors due to eclipsing... more We report on new estimates of the modulation expected in semiconductor detectors due to 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.

Research paper thumbnail of Experimental search for solar axions

Nuclear Physics B - Proceedings Supplements, 1999

A new technique has been used to search for solar axions using a single crystal germanium detecto... more A new technique has been used to search for solar axions using a single crystal germanium detector. It exploits the coherent conversion of axions into photons when their angle of incidence satisfies a Bragg condition with a crystalline plane. The analysis of approximately 1.94 kg.yr of data from the 1 kg DEMOS detector in Sierra Grande, Argentina, yields a new laboratory bound on axion-photon coupling of gaγγ < 2.7 × 10 −9 GeV −1 , independent of axion mass up to ∼ 1 keV. * Supported partially by grants from CONICET, Fundación ANTORCHAS and UNSAM

Research paper thumbnail of Recent results from the IGEX double-beta decay experiment

Nuclear Physics B - Proceedings Supplements, 1996

... c, D. Gonzfiles c, F. Haseabalg &amp;amp;amp;amp;quot;, WK Hensley b, IV Kirpichnikov d, ... more ... c, D. Gonzfiles c, F. Haseabalg &amp;amp;amp;amp;quot;, WK Hensley b, IV Kirpichnikov d, AA Klimenko e, HS Miley b, A. Morales , J. Morales c, A ... 1. The spectrum has been corrected as described previously [6] by subtracting the full energy background peaks and their Monte Carlo predicted continua. ...

Research paper thumbnail of The status of the IGEX 76Ge double-beta decay experiment in 1997

Nuclear Physics B - Proceedings Supplements, 1999

The International Germanium Experiment (IGEX) has six detectors containing N 90 fiducial moles of... more The International Germanium Experiment (IGEX) has six detectors containing N 90 fiducial moles of "Ge. Data from 74.84 fiducial mole years yield a lower bound Tp/y, > 0.8 x 10" y for neutrinoless double-beta decay of "Ge.

Research paper thumbnail of Solar axion experiments using coherent primakoff conversion in single crystals

Nuclear Physics B - Proceedings Supplements, 1999

The results of a 1.94 kg • y pilot search for solar axions with an ultralow background Ge detecto... more 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.

Research paper thumbnail of Looking for daily modulation effects of WIMPs in the Southern Hemisphere

Nuclear Physics B - Proceedings Supplements, 1996

... D. Abriolaa, FT Avignone IIIb, RL Brodzinskic, JI Collarb, HA Farachb, E. Garciad, AO Gattone... more ... D. Abriolaa, FT Avignone IIIb, RL Brodzinskic, JI Collarb, HA Farachb, E. Garciad, AO Gattone~, F. Hasenbalgb, H. Huck~, HS Miley A. Moralesd, J ... Data Group) the predicted signal is required not to be larger than the upper number of counts allowed in a Poisson process for No ...

Research paper thumbnail of Recent results from the ORPHEUS dark matter experiment

Nuclear Physics B - Proceedings Supplements, 2005

Research paper thumbnail of Improvement of the phase transition homogeneity of superheated superconducting tin granules

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2000

A considerably improved phase transition homogeneity was observed with superheated superconductin... more A considerably improved phase transition homogeneity was observed with superheated superconducting Sn spheres as a result of laser melting and fast cooling. These spheres exhibited a very homogeneous phase transition behaviour independent of the orientation of the spheres with respect to the direction of the external magnetic "eld. Compared to previously untreated Sn spheres the spread of the phase transition boundaries was reduced by almost an order of magnitude. In addition, we studied mass production of Sn structures using vacuum evaporation and deposition. First encouraging results are reported.

Research paper thumbnail of A decommissioned LHC model magnet as an axion telescope

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1999

The 8.4 T, 10 m long transverse magnetic field of a twin aperture LHC bending magnet can be utili... more 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 5°intheverticaldirectionand5°in the vertical direction and intheverticaldirectionand40°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 :9;10\ GeV\ 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. 0168-9002/99/$ -see front matter 1999 Elsevier Science B.V. All rights reserved. PII: S 0 1 6 8 -9 0 0 2 ( 9 8 ) 0 1 4 4 2 -9

Research paper thumbnail of Cerenkov Detector for Very High Energy Astroparticles

Extensive airshower detection is an important issue in current astrophysics endeavours. Surface a... more Extensive airshower detection is an important issue in current astrophysics endeavours. Surface arrays detectors are a common practice since they are easy to handle and have a 100% duty cycle. In this work we present an experimental study of the parameters relevant to the design of a water ÿ Cerenkov detector for high energy airshowers. This detector is conceived as part of the surface array of the Pierre Auger Project, which is expected to be sensitive to ultra high energy cosmic rays. In this paper we focus our attention in the geometry of the tank and its inner liner material, discussing pulse shapes and charge collections.

Research paper thumbnail of A water tank Cherenkov detector for very high-energy astroparticles

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1998

Extensive airshower detection is an important issue in current astrophysics endeavours. Surface a... more Extensive airshower detection is an important issue in current astrophysics endeavours. Surface arrays detectors are a common practice since they are easy to handle and have a 100% duty cycle. In this work we present an experimental study of the parameters relevant to the design of a waterČerenkov detector for high energy airshowers. This detector is conceived as part of the surface array of the Pierre Auger Project, which is expected to be sensitive to ultra high energy cosmic rays. In this paper we focus our attention in the geometry of the tank and its inner liner material, discussing pulse shapes and charge collections.

Research paper thumbnail of Properties and performance of the prototype instrument for the Pierre Auger Observatory

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2004

address: a.a.watson@leeds.ac.uk (A.A. Watson). 0168-9002/$ -see front matter r

Research paper thumbnail of Results from the ORPHEUS dark matter detector

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2004

The ORPHEUS dark matter detector consists of 450g superconducting tin granules with diameters of ... more The ORPHEUS dark matter detector consists of 450g superconducting tin granules with diameters of 28 and 36μm. The detector has been operating in the shallow site of the underground laboratory in Bern (70m.w.e). First preliminary results on WIMP detection sensitivity will be presented.

Research paper thumbnail of Improvement of the phase transition boundary with cylindrical tin arrays

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2006

ABSTRACT One of the limitations of the ORPHEUS dark matter detector performances was the phase tr... more ABSTRACT One of the limitations of the ORPHEUS dark matter detector performances was the phase transition smearing of the spherical granules. This could be dramatically improved by the use of cylindrical tin arrays. Results of measurements with prototypes are shown.

Research paper thumbnail of First runs with the ORPHEUS dark matter detector

Nuclear Physics B - Proceedings Supplements, 2002

The ORPHEUS dark matter experiment is completed at our shallow depth laboratory in Bern (70 m.w.e... more The ORPHEUS dark matter experiment is completed at our shallow depth laboratory in Bern (70 m.w.e.). The detector relies on measuring the magnetic flux variation produced by weakly interacting massive particles (WIMPS) as they heat 30 pm diameter superheated superconducting tin granules (SSG) and induce superconducting-tonormal phase transitions. In au initial phase, 0.45 kg of tin granules in a segmented detector volume have been used. Preliminary results of the experiment will be reported. 0920-5632/02/S -see front matter 0

Research paper thumbnail of Experimental Search for Solar Axions via Coherent Primakoff Conversion in a Germanium Spectrometer

Physical Review Letters, 1998

Results are reported of an experimental search for the unique, rapidly varying temporal pattern o... more Results are reported of an experimental search for the unique, rapidly varying temporal pattern of solar axions coherently converting into photons via the Primakoff effect in a single crystal germanium detector. This conversion is predicted when axions are incident at a Bragg angle with a crystalline plane.

Research paper thumbnail of Neutrinoless double-β decay of76Ge: First results from the International Germanium Experiment (IGEX) with six isotopically enriched detectors

Physical Review C, 1999

... E. Garcia,3 D. González,3 F. Hasenbalg,1,† ... in several conference proceedings 5. The summe... more ... E. Garcia,3 D. González,3 F. Hasenbalg,1,† ... in several conference proceedings 5. The summed energy of the two electrons from the neu-trinoless double-decay 76Ge⇒76Se2e would appear as a peak at 2038.50.4 keV 6 superimposed on the back-ground spectrum. ...

Research paper thumbnail of Fusion cross sections in systems leading to Hf170 at near-barrier energies

Physical Review C, 1995

In an effort to study the effect of the entrance channel mass asymmetry on the fusion process at ... more In an effort to study the effect of the entrance channel mass asymmetry on the fusion process at near-barrier energies, we have measured the fusion cross section and its distribution according to the different evaporation residues for the 28Si+142Ce, 32S+138Ba, and 48Ti+122Sn systems. All these systems lead to the same compound nucleus 170Hf. The measurements were performed using a delayed

Research paper thumbnail of Orbiting features in the strongly damped binary decay of the Si28+ O16 system

Physical Review C, 1996

The binary decay into strongly damped fragments and the quasielastic reactions of the 28 Siϩ 16 O... more The binary decay into strongly damped fragments and the quasielastic reactions of the 28 Siϩ 16 O system were measured at E lab ϭ107.5 and 139.0 MeV in the angular range of 30°р c.m. р150°using kinematic coincidence. The loss in the binary decay cross section due to light particle evaporation by the highly excited fragments was evaluated. The Q-value-integrated angular distributions of the primary decay exhibit the 1/sin c.m. behavior at backward angles, indicating a long lifetime. Mass distributions and the 16 O/ 12 C ratio suggest a noncompound process for the reaction mechanism. Coupled-channels calculations, including a great number of channels populated in the reactions, yield good agreement with the experimental angular distributions. ͓S0556-2813͑96͒03605-9͔

Research paper thumbnail of Absence of anomalous entrance channel effects in sub-barrier heavy ion fusion

Research paper thumbnail of Cold dark matter identification: Diurnal modulation reexamined

Nuclear Physics B - Proceedings Supplements, 1999

We report on new estimates of the modulation expected in semiconductor detectors due to eclipsing... more We report on new estimates of the modulation expected in semiconductor detectors due to 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.

Research paper thumbnail of Experimental search for solar axions

Nuclear Physics B - Proceedings Supplements, 1999

A new technique has been used to search for solar axions using a single crystal germanium detecto... more A new technique has been used to search for solar axions using a single crystal germanium detector. It exploits the coherent conversion of axions into photons when their angle of incidence satisfies a Bragg condition with a crystalline plane. The analysis of approximately 1.94 kg.yr of data from the 1 kg DEMOS detector in Sierra Grande, Argentina, yields a new laboratory bound on axion-photon coupling of gaγγ < 2.7 × 10 −9 GeV −1 , independent of axion mass up to ∼ 1 keV. * Supported partially by grants from CONICET, Fundación ANTORCHAS and UNSAM

Research paper thumbnail of Recent results from the IGEX double-beta decay experiment

Nuclear Physics B - Proceedings Supplements, 1996

... c, D. Gonzfiles c, F. Haseabalg &amp;amp;amp;amp;quot;, WK Hensley b, IV Kirpichnikov d, ... more ... c, D. Gonzfiles c, F. Haseabalg &amp;amp;amp;amp;quot;, WK Hensley b, IV Kirpichnikov d, AA Klimenko e, HS Miley b, A. Morales , J. Morales c, A ... 1. The spectrum has been corrected as described previously [6] by subtracting the full energy background peaks and their Monte Carlo predicted continua. ...

Research paper thumbnail of The status of the IGEX 76Ge double-beta decay experiment in 1997

Nuclear Physics B - Proceedings Supplements, 1999

The International Germanium Experiment (IGEX) has six detectors containing N 90 fiducial moles of... more The International Germanium Experiment (IGEX) has six detectors containing N 90 fiducial moles of "Ge. Data from 74.84 fiducial mole years yield a lower bound Tp/y, > 0.8 x 10" y for neutrinoless double-beta decay of "Ge.

Research paper thumbnail of Solar axion experiments using coherent primakoff conversion in single crystals

Nuclear Physics B - Proceedings Supplements, 1999

The results of a 1.94 kg • y pilot search for solar axions with an ultralow background Ge detecto... more 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.

Research paper thumbnail of Looking for daily modulation effects of WIMPs in the Southern Hemisphere

Nuclear Physics B - Proceedings Supplements, 1996

... D. Abriolaa, FT Avignone IIIb, RL Brodzinskic, JI Collarb, HA Farachb, E. Garciad, AO Gattone... more ... D. Abriolaa, FT Avignone IIIb, RL Brodzinskic, JI Collarb, HA Farachb, E. Garciad, AO Gattone~, F. Hasenbalgb, H. Huck~, HS Miley A. Moralesd, J ... Data Group) the predicted signal is required not to be larger than the upper number of counts allowed in a Poisson process for No ...

Research paper thumbnail of Recent results from the ORPHEUS dark matter experiment

Nuclear Physics B - Proceedings Supplements, 2005

Research paper thumbnail of Improvement of the phase transition homogeneity of superheated superconducting tin granules

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2000

A considerably improved phase transition homogeneity was observed with superheated superconductin... more A considerably improved phase transition homogeneity was observed with superheated superconducting Sn spheres as a result of laser melting and fast cooling. These spheres exhibited a very homogeneous phase transition behaviour independent of the orientation of the spheres with respect to the direction of the external magnetic "eld. Compared to previously untreated Sn spheres the spread of the phase transition boundaries was reduced by almost an order of magnitude. In addition, we studied mass production of Sn structures using vacuum evaporation and deposition. First encouraging results are reported.

Research paper thumbnail of A decommissioned LHC model magnet as an axion telescope

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1999

The 8.4 T, 10 m long transverse magnetic field of a twin aperture LHC bending magnet can be utili... more 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 5°intheverticaldirectionand5°in the vertical direction and intheverticaldirectionand40°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 :9;10\ GeV\ 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. 0168-9002/99/$ -see front matter 1999 Elsevier Science B.V. All rights reserved. PII: S 0 1 6 8 -9 0 0 2 ( 9 8 ) 0 1 4 4 2 -9

Research paper thumbnail of Cerenkov Detector for Very High Energy Astroparticles

Extensive airshower detection is an important issue in current astrophysics endeavours. Surface a... more Extensive airshower detection is an important issue in current astrophysics endeavours. Surface arrays detectors are a common practice since they are easy to handle and have a 100% duty cycle. In this work we present an experimental study of the parameters relevant to the design of a water ÿ Cerenkov detector for high energy airshowers. This detector is conceived as part of the surface array of the Pierre Auger Project, which is expected to be sensitive to ultra high energy cosmic rays. In this paper we focus our attention in the geometry of the tank and its inner liner material, discussing pulse shapes and charge collections.

Research paper thumbnail of A water tank Cherenkov detector for very high-energy astroparticles

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1998

Extensive airshower detection is an important issue in current astrophysics endeavours. Surface a... more Extensive airshower detection is an important issue in current astrophysics endeavours. Surface arrays detectors are a common practice since they are easy to handle and have a 100% duty cycle. In this work we present an experimental study of the parameters relevant to the design of a waterČerenkov detector for high energy airshowers. This detector is conceived as part of the surface array of the Pierre Auger Project, which is expected to be sensitive to ultra high energy cosmic rays. In this paper we focus our attention in the geometry of the tank and its inner liner material, discussing pulse shapes and charge collections.

Research paper thumbnail of Properties and performance of the prototype instrument for the Pierre Auger Observatory

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2004

address: a.a.watson@leeds.ac.uk (A.A. Watson). 0168-9002/$ -see front matter r

Research paper thumbnail of Results from the ORPHEUS dark matter detector

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2004

The ORPHEUS dark matter detector consists of 450g superconducting tin granules with diameters of ... more The ORPHEUS dark matter detector consists of 450g superconducting tin granules with diameters of 28 and 36μm. The detector has been operating in the shallow site of the underground laboratory in Bern (70m.w.e). First preliminary results on WIMP detection sensitivity will be presented.