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1.	Abdo, A. A., et al. (author) FERMI LARGE AREA TELESCOPE OBSERVATIONS OF THE VELA PULSAR 2009 In: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 696:2, s. 1084-1093 Journal article (peer-reviewed)abstract The Vela pulsar is the brightest persistent source in the GeV sky and thus is the traditional first target for new gamma-ray observatories. We report here on initial Fermi Large Area Telescope observations during verification phase pointed exposure and early sky survey scanning. We have used the Vela signal to verify Fermi timing and angular resolution. The high-quality pulse profile, with some 32,400 pulsed photons at E >= 0.03 GeV, shows new features, including pulse structure as fine as 0.3 ms and a distinct third peak, which shifts in phase with energy. We examine the high-energy behavior of the pulsed emission; initial spectra suggest a phase-averaged power-law index of Gamma = 1.51(-0.04)(+0.05) with an exponential cutoff at E-c = 2.9 +/- 0.1 GeV. Spectral fits with generalized cutoffs of the form e(-(E/Ec)b) require b <= 1, which is inconsistent with magnetic pair attenuation, and thus favor outer-magnetosphere emission models. Finally, we report on upper limits to any unpulsed component, as might be associated with a surrounding pulsar wind nebula.
2.	Atwood, W. B., et al. (author) THE LARGE AREA TELESCOPE ON THE FERMI GAMMA-RAY SPACE TELESCOPE MISSION 2009 In: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 697:2, s. 1071-1102 Journal article (peer-reviewed)abstract The Large Area Telescope (Fermi/LAT, hereafter LAT), the primary instrument on the Fermi Gamma-ray Space Telescope (Fermi) mission, is an imaging, wide field-of-view (FoV), high-energy gamma-ray telescope, covering the energy range from below 20 MeV to more than 300 GeV. The LAT was built by an international collaboration with contributions from space agencies, high-energy particle physics institutes, and universities in France, Italy, Japan, Sweden, and the United States. This paper describes the LAT, its preflight expected performance, and summarizes the key science objectives that will be addressed. On-orbit performance will be presented in detail in a subsequent paper. The LAT is a pair-conversion telescope with a precision tracker and calorimeter, each consisting of a 4 x 4 array of 16 modules, a segmented anticoincidence detector that covers the tracker array, and a programmable trigger and data acquisition system. Each tracker module has a vertical stack of 18 (x, y) tracking planes, including two layers (x and y) of single-sided silicon strip detectors and high-Z converter material (tungsten) per tray. Every calorimeter module has 96 CsI(Tl) crystals, arranged in an eight-layer hodoscopic configuration with a total depth of 8.6 radiation lengths, giving both longitudinal and transverse information about the energy deposition pattern. The calorimeter's depth and segmentation enable the high-energy reach of the LAT and contribute significantly to background rejection. The aspect ratio of the tracker (height/width) is 0.4, allowing a large FoV (2.4 sr) and ensuring that most pair-conversion showers initiated in the tracker will pass into the calorimeter for energy measurement. Data obtained with the LAT are intended to (1) permit rapid notification of high-energy gamma-ray bursts and transients and facilitate monitoring of variable sources, (2) yield an extensive catalog of several thousand high-energy sources obtained from an all-sky survey, (3) measure spectra from 20 MeV to more than 50 GeV for several hundred sources, (4) localize point sources to 0.3-2 arcmin, (5) map and obtain spectra of extended sources such as SNRs, molecular clouds, and nearby galaxies, (6) measure the diffuse isotropic gamma-ray background up to TeV energies, and (7) explore the discovery space for dark matter.
3.	Abdo, A. A., et al. (author) The on-orbit calibration of the Fermi Large Area Telescope 2009 In: Astroparticle physics. - : Elsevier BV. - 0927-6505 .- 1873-2852. ; 32:3-4, s. 193-219 Journal article (peer-reviewed)abstract The Large Area Telescope (LAT) on-board the Fermi Gamma-ray Space Telescope began its on-orbit operations on June 23, 2008. Calibrations, defined in a generic sense, correspond to synchronization of trigger signals, optimization of delays for latching data, determination of detector thresholds, gains and responses, evaluation of the perimeter of the South Atlantic Anomaly (SAA), measurements of live time, of absolute time, and internal and spacecraft boresight alignments. Here we describe on-orbit calibration results obtained using known astrophysical sources, galactic cosmic rays, and charge injection into the front-end electronics of each detector. Instrument response functions will be described in a separate publication. This paper demonstrates the stability of calibrations and describes minor changes observed since launch. These results have been used to calibrate the LAT datasets to be publicly released in August 2009.
4.	Greiner, J., et al. (author) GRIPS - Gamma-Ray Imaging, Polarimetry and Spectroscopy 2012 In: Experimental astronomy. - : Springer Science and Business Media LLC. - 0922-6435 .- 1572-9508. ; 34:2, s. 551-582 Journal article (peer-reviewed)abstract We propose to perform a continuously scanning all-sky survey from 200 keV to 80 MeV achieving a sensitivity which is better by a factor of 40 or more compared to the previous missions in this energy range (COMPTEL, INTEGRAL; see Fig. 1). These gamma-ray observations will be complemented by observations in the soft X-ray and (near-)infrared region with the corresponding telescopes placed on a separate satellite. The Gamma-Ray Imaging, Polarimetry and Spectroscopy ("GRIPS") mission with its three instruments Gamma-Ray Monitor (GRM), X-Ray Monitor (XRM) and InfraRed Telescope (IRT) addresses fundamental questions in ESA's Cosmic Vision plan. Among the major themes of the strategic plan, GRIPS has its focus on the evolving, violent Universe, exploring a unique energy window. We propose to investigate γ-ray bursts and blazars, the mechanisms behind supernova explosions, nucleosynthesis and spallation, the enigmatic origin of positrons in our Galaxy, and the nature of radiation processes and particle acceleration in extreme cosmic sources including pulsars and magnetars. The natural energy scale for these non-thermal processes is of the order of MeV. Although they can be partially and indirectly studied using other methods, only the proposed GRIPS measurements will provide direct access to their primary photons. GRIPS will be a driver for the study of transient sources in the era of neutrino and gravitational wave observatories such as IceCUBE and LISA, establishing a new type of diagnostics in relativistic and nuclear astrophysics. This will support extrapolations to investigate star formation, galaxy evolution, and black hole formation at high redshifts.
5.	Atwood, W. B., et al. (author) THE LARGE AREA TELESCOPE ON THE FERMI GAMMA-RAY SPACE TELESCOPE MISSION 2009 In: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 697:2, s. 1071-1102 Journal article (peer-reviewed)abstract The Large Area Telescope (Fermi/LAT, hereafter LAT), the primary instrument on the Fermi Gamma-ray Space Telescope (Fermi) mission, is an imaging, wide field-of-view (FoV), high-energy gamma-ray telescope, covering the energy range from below 20 MeV to more than 300 GeV. The LAT was built by an international collaboration with contributions from space agencies, high-energy particle physics institutes, and universities in France, Italy, Japan, Sweden, and the United States. This paper describes the LAT, its preflight expected performance, and summarizes the key science objectives that will be addressed. On-orbit performance will be presented in detail in a subsequent paper. The LAT is a pair-conversion telescope with a precision tracker and calorimeter, each consisting of a 4 x 4 array of 16 modules, a segmented anticoincidence detector that covers the tracker array, and a programmable trigger and data acquisition system. Each tracker module has a vertical stack of 18 (x, y) tracking planes, including two layers (x and y) of single-sided silicon strip detectors and high-Z converter material (tungsten) per tray. Every calorimeter module has 96 CsI(Tl) crystals, arranged in an eight-layer hodoscopic configuration with a total depth of 8.6 radiation lengths, giving both longitudinal and transverse information about the energy deposition pattern. The calorimeter's depth and segmentation enable the high-energy reach of the LAT and contribute significantly to background rejection. The aspect ratio of the tracker (height/width) is 0.4, allowing a large FoV (2.4 sr) and ensuring that most pair-conversion showers initiated in the tracker will pass into the calorimeter for energy measurement. Data obtained with the LAT are intended to (1) permit rapid notification of high-energy gamma-ray bursts and transients and facilitate monitoring of variable sources, (2) yield an extensive catalog of several thousand high-energy sources obtained from an all-sky survey, (3) measure spectra from 20 MeV to more than 50 GeV for several hundred sources, (4) localize point sources to 0.3-2 arcmin, (5) map and obtain spectra of extended sources such as SNRs, molecular clouds, and nearby galaxies, (6) measure the diffuse isotropic gamma-ray background up to TeV energies, and (7) explore the discovery space for dark matter.
6.	HILDINGSSON, L, et al. (author) HIGH-SPIN PHENOMENA IN OS-174 1992 In: Nuclear Physics A. - 0375-9474 .- 1873-1554. ; 545:4, s. 871-888 Journal article (peer-reviewed)abstract High-spin states of 174Os have been investigated by means of the (Nd(S, 4n)Os)-Nd-146-S-32-Os-174 reaction using the ESSA30 multidetector system. The decay is dominated by the ground-state positive-parity band, two negative-parity 4- and 5- bands and another band starting at spin 9. Deformed shell-model calculations have been carried out to interpret the observed band structures. The role of the strongly shape-driving, non-aligned, pi-h9/2 configuration in the low-spin region of the ground-state band is discussed. The first band crossing is interpreted as due to the nu-i13/2 alignment. The two lowest side-bands are understood in terms of coupling to octupole excitations.
7.	Ideguchi, E., et al. (author) Orbifold projection in supersymmetric QCD at N(f) ≤ N(c) 2000 In: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - 0370-2693. ; 492:3-4, s. 369-375 Journal article (peer-reviewed)abstract Supersymmetric orbifold projection of N = 1 SQCD with relatively small number of flavors (N(f) ≤ N(c)) is considered. The purpose is to check whether orbifolding commutes with the infrared limit. On the one hand, one considers the orbifold projection of SQCD and obtains the low-energy description of the resulting theory. On the other hand, one starts with the low-energy effective theory of the original SQCD, and only then performs orbifolding. It is shown that at finite N(c) the two low-energy theories obtained in these ways are different. However, in the case of stabilized run-away vacuum these two theories are shown to coincide in the large N(c) limit. In the case of quantum modified moduli space, topological solitons carrying baryonic charges are present in the orbifolded low-energy theory. These solitons may restore the correspondence between the two theories provided that the soliton mass tends to zero in the large N(c) limit. (C) 2000 Elsevier Science B.V.
8.	Kamae, T., et al. (author) A High Sensitivity Balloon-Borne Soft Gamma-ray Polarimeter PoGOLite 2006 In: AAS/High Energy Astrophysics Division #9. Conference paper (other academic/artistic)
9.	KLAMRA, W, et al. (author) HIGH-SPIN BAND STRUCTURES IN CD-104 1995 In: Zeitschrift für Physik A Hadrons and Nuclei. - 0939-7922 .- 1431-5831. ; 352:2, s. 117-118 Journal article (peer-reviewed)abstract High spin states in Cd-104 have been investigated by means of heavy ion induced reactions using the Nordball detector array. The level scheme constructed from yy-coincidences is dominated by three band structures, The positive parity band shows no rotational like energy spacing, It is thus understood mostly in terms of quasiparticle excitations with vd(5/2), Vg(7/2) and pi g(9/2) configurations, The collective properties of the negative parity bands are more pronounced. These bands are most likely due to v(h(11/2),d(5/2)) and v(h(11/2)g(7/2)) structures.
10.	KLAMRA, W, et al. (author) HIGH-SPIN BAND STRUCTURES IN CD-104 1995 In: ZEITSCHRIFT FUR PHYSIK A-HADRONS AND NUCLEI. - : SPRINGER VERLAG. - 0939-7922. ; 352:2, s. 117-118 Journal article (peer-reviewed)abstract High spin states in Cd-104 have been investigated by means of heavy ion induced reactions using the Nordball detector array. The level scheme constructed from yy-coincidences is dominated by three band structures, The positive parity band shows no rotatio
11.	Sohler, D., et al. (author) Yrast states of the proton drip line nucleus 106 Sb 1999 In: Physical Review C - Nuclear Physics. - 2469-9985 .- 2469-9993 .- 0556-2813 .- 1089-490X. ; 59:3, s. 1324-1327 Journal article (peer-reviewed)abstract Yrast states of [Formula Presented] have been investigated in the [Formula Presented] reaction using in-beam [Formula Presented]-spectroscopic methods and in the [Formula Presented] reaction performing delayed [Formula Presented] and conversion electron studies. A new isomeric state was found at 103 keV with [Formula Presented] The number of states and transitions in the proposed level scheme have been doubled. The experimental results are discussed within the framework of the shell model. © 1999 The American Physical Society.
12.	Abdo, A. A., et al. (author) FERMI LARGE AREA TELESCOPE OBSERVATIONS OF THE VELA PULSAR 2009 In: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 696:2, s. 1084-1093 Journal article (peer-reviewed)abstract The Vela pulsar is the brightest persistent source in the GeV sky and thus is the traditional first target for new gamma-ray observatories. We report here on initial Fermi Large Area Telescope observations during verification phase pointed exposure and early sky survey scanning. We have used the Vela signal to verify Fermi timing and angular resolution. The high-quality pulse profile, with some 32,400 pulsed photons at E >= 0.03 GeV, shows new features, including pulse structure as fine as 0.3 ms and a distinct third peak, which shifts in phase with energy. We examine the high-energy behavior of the pulsed emission; initial spectra suggest a phase-averaged power-law index of Gamma = 1.51(-0.04)(+0.05) with an exponential cutoff at E-c = 2.9 +/- 0.1 GeV. Spectral fits with generalized cutoffs of the form e(-(E/Ec)b) require b <= 1, which is inconsistent with magnetic pair attenuation, and thus favor outer-magnetosphere emission models. Finally, we report on upper limits to any unpulsed component, as might be associated with a surrounding pulsar wind nebula.
13.	Axelsson, Magnus, et al. (author) Measuring energy dependent polarization in soft γ-rays using Compton scattering in PoGOLite 2007 In: Astroparticle Physics. - : Elsevier BV. - 0927-6505. ; 28:3, s. 327-337 Journal article (peer-reviewed)abstract Linear polarization in X- and γ-rays is an important diagnostic of many astrophysical sources, foremost giving information about their geometry, magnetic fields, and radiation mechanisms. However, very few X-ray polarization measurements have been made, and then only mono-energetic detections, whilst several objects are assumed to have energy dependent polarization signatures. In this paper, we investigate whether detection of energy dependent polarization from cosmic sources is possible using the Compton technique, in particular with the proposed PoGOLite balloon-experiment, in the 25–100 keV range. We use Geant4 simulations of a PoGOLite model and input photon spectra based on Cygnus X-1 and accreting magnetic pulsars (100 mCrab). Effective observing times of 6 and 35 h were simulated, corresponding to a standard and a long duration flight, respectively. Both smooth and sharp energy variations of the polarization are investigated and compared to constant polarization signals using chi-square statistics. We can reject constant polarization, with energy, for the Cygnus X-1 spectrum (in the hard state), if the reflected component is assumed to be completely polarized, whereas the distinction cannot be made for weaker polarization. For the accreting pulsar, constant polarization can be rejected in the case of polarization in a narrow energy band with at least 50% polarization, and similarly for a negative step distribution from 30% to 0% polarization.
14.	Bergenius, S., et al. (author) Proton irradiation response of CsI(Tl) crystals for the GLAST calorimeter 2003 In: 2003 IEEE Nuclear Science Symposium Conference Record. - : IEEE Press. - 0780382579 ; , s. 1096-1099 Conference paper (peer-reviewed)abstract The electromagnetic calorimeter of the Gamma-Ray Large Area Space Telescope (GLAST) consists of 16 towers of CsI(Tl) crystals. Each tower contains 8 layers of crystals (each 326.0x26.7x19.9 mm3) arranged in a hodoscopic fashion. The crystals are read out at both ends with photodiodes. Crystals produced by Amcrys-H (Ukraine) are used. A full size crystal was irradiated with a 180 MeV proton beam and the radiation induced attenuation was measured. The induced radioactivity of the crystal was also studied. In this paper we will discuss the damage due to proton irradiation and compare this with the expected in-orbit background flux.
15.	Bergenius, S., et al. (author) Radiation hardness tests of CSI(Tl) crystals for the GLAST electromagnetic calorimeter 2003 In: Proceedings of 28th International Cosmic Ray Conference. ; , s. 2787-2790 Conference paper (peer-reviewed)abstract The electromagnetic calorimeter of the Gamma ray Large Area Space Telescope(GLAST) consists of 16 towers of CsI(Tl) crystals. Each tower contains 8layers of crystals (each 326.0×26.7×19.9 mm3) arranged in a hodoscopic fashion.The crystals are read out at both ends with PIN photodiodes. Crystals producedby Amcrys-H (Ukraine) are used. As a part of the quality control procedureduring crystal production, samples from the uncut boules are systematically irradiatedwith gamma rays from a 60Co source. Studies have also been carried outto verify the correspondence between the post-irradiation properties of the boulesamples and the full size crystals which are subsequently cut from the boule. Thefull size crystals have also been irradiated with a 180 MeV proton beam and theradiation induced attenuation measured.
16.	Cederkall, J, et al. (author) First evidence for excited states in In-101 1996 In: PHYSICAL REVIEW C-NUCLEAR PHYSICS. - : AMER INST PHYSICS. - 0556-2813. ; 53:4, s. 1955-1958 Journal article (other academic/artistic)abstract The first evidence for excited states in In-101 is presented. In-101 is the lightest In isotope observed in an in-beam experiment. Two gamma-ray transitions at 1309 and 341 keV, respectively, are strong candidates for a cascade to the ground state in this
17.	Cederkall, J, et al. (author) Maximum spin aligned states in Ag-98(47)51 1998 In: EUROPEAN PHYSICAL JOURNAL A. - : SPRINGER VERLAG. - 1434-6001. ; 1:1, s. 7-9 Journal article (other academic/artistic)abstract New excited states have been observed in the neutron deficient isotope Ag-98 following the Ni-58+Cr-50-->Te-108* heavy-ion reaction. One of these states may be interpreted as a maximum spin aligned state of the pi g(9/2)(-3) nu vg(7/2) configuration. Othe
18.	Danko, I, et al. (author) Collective and broken pair states of Ga-65,Ga-67 1999 In: PHYSICAL REVIEW C-NUCLEAR PHYSICS. - : AMERICAN PHYSICAL SOC. - 0556-2813. ; 59:4, s. 1956-1974 Journal article (other academic/artistic)abstract Excited states of Ga-65 and Ga-67 nuclei were populated through the C-12(Ni-58,alpha p) and C-12(Ni-58,3p) reactions, respectively, and investigated by in-beam gamma-ray spectroscopic methods. The NORDBALL array equipped with a charged particle ball and 1
19.	Ideguchi, Eiji, et al. (author) Superdeformation in 91Tc 2000 In: Physics Letters B. - : Elsevier. - 0370-2693 .- 1873-2445. ; 492:3-4, s. 245-253 Journal article (peer-reviewed)abstract A high-spin rotational band with 11 gamma -ray transitions has barn observed in Tc-91. The dynamical moment of inertia as well as the transition quadrupole moment of 8.1(-1.4)(+1.9) eb measured for this band show the characteristics of a superdeformed band. However, the shape is more elongated than in the neighbouring A = 80-90 superdeformed nuclei. Theoretical interpretations of the band within the cranked Strutinsky approach based on two different Woods-Saxon potential parameterisations are presented. Even though an unambiguous configuration assignment proved difficult, both calculations indicate a larger deformation and at least three additional high-N intruder orbitals occupied compared to the lighter SD nuclei. (C) 2000 Elsevier Science B.V. All rights reserved.
20.	JERRESTAM, D, et al. (author) COLLECTIVE EXCITATIONS IN CD-106 1994 In: Nuclear Physics A. - : Elsevier BV. - 0375-9474 .- 1873-1554. ; 571:2, s. 393-412 Journal article (peer-reviewed)abstract High Spin states in 106Cd were populated by the reactions Zr-94(O-17, 5n) and Ge(S-32, 4n) at 80 MeV and at 148 MeV, respectively. The gamma-decay was studied by gamma-spectroscopic methods using the Nordball multi-detector army. Protons and alpha-particles were detected in particle detector system, thus selecting the neutron channel. The experiment included gamma-ray yields, gammagamma-coincidences and gamma-ray angular relation measurements. Collective bands extending up to spin 26+, 20- and 21-, have been observed in 106Cd. A new lifetime Of 11(-3)+6 ns for the 16+ state at 7118.7 keV has been found. Both total Routhian surfaces and spin diabatic surfaces have been calculated and used for assigning quasiparticle configurations to the bands. The (+, 0) band is assigned as a nuh11/2(2) configuration below I = 16+ and at higher spins suggested to be built on a pig9/2(2)nuh11/2(2) configuration. The large hindrance observed for the decay from the 16+ state supports the latter assignment. With the alignment of the nuh11/12(2) pair the deformation is predicted to change from (epsilon2,gamma) = (0.13,-2-degrees) to (0.17, 4-degrees). The configuration of the negative parity bands is assigned as either a nuh11/2(1)d5/2(1) or a nuh11/2(1)(g7/2xd5/2)1, With (epsilon2, gamma) = (0.14,9-degrees.
21.	Jerrestam, Dan, et al. (author) High spin bands in Pd-102 1996 In: NUCLEAR PHYSICS A. - : ELSEVIER SCIENCE BV. - 0375-9474. ; 603:2, s. 203-218 Journal article (peer-reviewed)abstract The nucleus Pd-102 has been studied using 148 MeV S-34 ions impinging on Ge-76. The gamma-rays were detected with the Nordball array and the light charged particles with a 4 pi charged particle detector system. Rotational bands have been extended using ga
22.	JERRESTAM, Dan, et al. (author) HIGHLY DEFORMED BAND IN AG-105 1995 In: PHYSICAL REVIEW C-NUCLEAR PHYSICS. - : AMER INST PHYSICS. - 0556-2813. ; 52:5, s. 2448-2454 Journal article (peer-reviewed)abstract The isotope Ag-105 has been studied using 169.5 MeV Cl-37 ions impinging on Ge-76. The Nordball Ge array detected the gamma rays and a 4 pi charged particle detector system detected emitted light charged particles. A very deformed band has been establishe
23.	JERRESTAM, Dan, et al. (author) IN-BEAM SPECTROSCOPIC STUDIES OF THE NUCLEUS CD-105 1995 In: NUCLEAR PHYSICS A. - : ELSEVIER SCIENCE BV. - 0375-9474. ; 593:2, s. 162-176 Journal article (peer-reviewed)abstract High spin states in Cd-105 have been studied using reactions Cd-106(p, pn), Cd-106(He-3, 2p2n), Zr-92(O-16, 3n) and Ge-76(S-34, 5n). The excited levels are dominated by a negative parity band structure up to spin 47/2(-) and a positive parity structure up
24.	Klamra, Wlodzimierz, et al. (author) Extensive studies on light yield non-proportional response of undoped CeF3 at room and liquid nitrogen temperatures 2013 In: Journal of Instrumentation. - 1748-0221. ; 8:6, s. P06003- Journal article (peer-reviewed)abstract In this paper properties of various undoped CeF3 scintillators were investigated at room and liquid nitrogen (LN2) temperatures. The study was focused on measurements of radioluminescence spectra, decay time, non-proportional response to X-and gamma-rays, energy and intrinsic resolution at different temperature environment. Surprisingly, all the tested pure CeF3 crystals show non-proportional response up to 5.1 MeV gamma ray energy, which is contrary to the typical nonproportionality observed below 100 keV for most of the inorganic scintillators. The investigation of the phenomenon occurring in CeF3 scintillators would be another step to get a better knowledge of the scintillators nature, which still has not been entirely understood.
25.	Klamra, Wlodzimierz, et al. (author) High-spin multiparticle-hole excitations in Eu-148 2001 In: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-6001 .- 1434-601X. ; 10:1, s. 11-12 Journal article (peer-reviewed)abstract Studies by means of 155 MeV Al-27 bombardment on a Te-130 target revealed in Eu-148 high-spin structures up to spin 31 (n) over tilde, in addition to a cascade extended to the 11088.1 keV excitation. The observed levels are tentatively assigned as complex multiparticle-hole proton and neutron configurations.
26.	Klamra, Wlodzimierz, et al. (author) Light yield non-proportionality of undoped YAP scintillator 2009 In: Journal of Instrumentation. - : IOP Publishing. - 1748-0221. ; 4 Journal article (peer-reviewed)abstract Scintillation properties of undoped YAP crystal were studied. The emission spectra show a very intense light component at 360 nm. Analysis of the light pulse shape resulted in five components, four of them, with time constants of 38+/-2 ns, 92+/-3 ns, 7.5+/-0.5 mu s and 24+/-3 mu s, representing high light intensity. The light yield was found to be temperature dependent, N-ph=3090+/-130 ph/MeV at liquid nitrogen temperature and N-ph=1440+/-60 ph/MeV at room temperature. Also the light yield non-proportionality shows temperature dependence and is more pronounced at room temperature.
27.	Kownacki, J, et al. (author) High-spin studies of the neutron deficient nuclei In-103, In-105, In-107, and In-109 1997 In: Nuclear Physics A. - 0375-9474 .- 1873-1554. ; 627:2, s. 239-258 Journal article (peer-reviewed)abstract High-spin states of the isotopes 103,105,107,109In have been investigated using in-beam γ-ray spectroscopic methods. Results from three different experiments are presented. Targets of 54Fe, 50Cr, and 92Mo were bombarded by a 270 and 261 MeV 58Ni beam and by a 95 MeV 19F beam, respectively. Reaction channel separation was achieved with a charged-particle detector array and in the first two experiments also with a 1π neutron detector system. As a result of these experiments the level schemes of 103,105,107,109In were significantly extended. Excited states of these odd-A indium isotopes are discussed within the framework of the nuclear shell model and the hole-core coupling scheme. The systematics of excited states of light odd-A indium isotopes is also discussed.
28.	Kownacki, J, et al. (author) The isospin dependent p-n multiplets in the region of doubly magic Sn-100 1996 Conference paper (peer-reviewed)abstract Experimental data on p-n multiplets appearing in the nuclei near double-magic Sn-100 accesible in heavy-ion fusion-evaporation experiments have been analyzed. Proton-rich nuclei in this region have been investigated using the NORDBALL array. A Ni-58 beams at energies of 270 Mev on Fe-54 and 261 MeV on Cr-50 targets were used. Reaction channel separation was achieved with a 4 pi charged particle multi-detector set-up together with a 1 pi neutron detector wall placed in the forward direction. On the basis of gamma gamma-coincidence and angular correlation relations a level schemes of several light Sn, In, Sb, Te and I nuclei were observed for the first time in the present experiment. The observed structure of nuclei are discussed in the framework of the nuclear shell-model. The p-n multiplets in the A similar to 100 region corresponding to the nucleon pairs with mixed configurations has been considered as a playground for the tests of the T = 0 and T = 1 parts of the effective interaction.
29.	Kownacki, J, et al. (author) The isospin dependent p-n multiplets in the region of doubly magic Sn-100 1996 In: ACTA PHYSICA POLONICA B. - : POLISH ACAD SCIENCES INST PHYSICS. ; 27:1-2, s. 87-97 Journal article (other academic/artistic)abstract Experimental data on p-n multiplets appearing in the nuclei near double-magic Sn-100 accesible in heavy-ion fusion-evaporation experiments have been analyzed. Proton-rich nuclei in this region have been investigated using the NORDBALL array. A Ni-58 beams
30.	Kurita, K., et al. (author) Recent Development Status of PoGOLite 2009 In: Astrophysics with All-Sky X-Ray Observations. ; , s. 386- Conference paper (other academic/artistic)
31.	Lipoglav, M., et al. (author) Stability of $_50^100Sn_50$ Deduced from Excited States in $_48^99Cd_51$ 1996 In: Phys. Rev. Lett.. ; 76:6, s. 888-891 Journal article (peer-reviewed)
32.	Lipoglavsek, M, et al. (author) Stability of Sn-100(50)50 deduced from excited states in Cd-99(48)51 stability of 1996 In: PHYSICAL REVIEW LETTERS. - : AMER INST PHYSICS. - 0031-9007. ; 76:6, s. 888-891 Journal article (other academic/artistic)abstract Excited states of neutron deficient nuclei close to Sn-100 were investigated in an in-beam spectroscopic experiment using the NORDBALL detector array. Excited states in Cd-99 were identified for the first time. The measured half-life of an isomeric state
33.	Mizuno, T., et al. (author) A Monte Carlo method for calculating the energy response of plastic scintillators to polarized photons below 100 keV 2009 In: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 600:3, s. 609-617 Journal article (peer-reviewed)abstract The energy response of plastic scintillators (Eljen Technology EJ-204) to polarized soft gamma-ray photons below 100 keV has been studied, primarily for the balloon-borne polarimeter, PoGOLite. The response calculation includes quenching effects due to low-energy recoil electrons and the position dependence of the light collection efficiency in a 20 cm long scintillator rod. The broadening of the pulse-height spectrum, presumably caused by light transportation processes inside the scintillator, as well as the generation and multiplication of photoelectrons in the photomultiplier tube, were studied experimentally and have also been taken into account. A Monte Carlo simulation based on the Geant4 toolkit was used to model photon interactions in the scintillators. When using the polarized Compton/Rayleigh scattering processes previously corrected by the authors, scintillator spectra and angular distributions of scattered polarized photons could clearly be reproduced, in agreement with the results obtained at a synchrotron beam test conducted at the KEK Photon Factory. Our simulation successfully reproduces the modulation factor, defined as the ratio of the amplitude to the mean of the distribution of the azimuthal scattering angles, within similar to 5% (relative). Although primarily developed for the PoGOLite mission, the method presented here is also relevant for other missions aiming to measure polarization from astronomical objects using plastic scintillator scatterers.
34.	Mizuno, T., et al. (author) High sensitivity balloon-borne hard X-ray/soft Gamma-Ray Polarimeter PoGOLite 2007 In: Nuclear Science Symposium Conference Record, 2007. NSS ’07. IEEE. - : IEEE. - 9781424409228 ; , s. 2538-2544 Conference paper (peer-reviewed)abstract The Polarized Gamma-ray Observer - Lightweight version (PoGOLite) is a new balloon experiment capable of detecting 10% polarization from a 200 mCrab source in the 25-80 keV energy range in a single 6-hour flight for the first time. Polarization measurements of hard X-rays and soft gamma-rays are expected to provide a powerful probe into high-energy emission mechanisms as well as source geometries. PoGOLite uses Compton scattering and photo-absorption to measure polarization in an array of 217 well-type phoswich detector cells made of plastic and BGO scintillators. The adoption of a well-type phoswich counter concept and a thick polyethylene neutron shield provides a narrow field-of-view (1.25 msr), a large effective area ( gt; 250 cm2 at 40-50 keV), a high modulation factor (more than 25%) and the low background ( 100 mCrab) required to conduct high-sensitivity polarization measurements. Through tests in laboratories and accelerator facilities of a scaled-down prototype with the front-end electronics of flight design and an extensive study by Monte Carlo simulation, we have demonstrated high instrument performance. PoGOLite will be ready for a first engineering flight in 2009 and a science flight in 2010, during which polarization signals from the Crab Nebula/pulsar, Cygnus X-1 and other objects will be observed.
35.	Moszynski, A., et al. (author) Intrinsic energy resolution and light yield nonproportionality of BGO 2004 In: IEEE Transactions on Nuclear Science. - 0018-9499 .- 1558-1578. ; 51:3, s. 1074-1079 Journal article (peer-reviewed)abstract The intrinsic energy resolution and nonproportionality of the light yield as a function of gamma ray energies, in the energy range of 14 keV to 1.33 MeV, were studied for small BGO (Bi4Ge3O12) crystals at room and liquid nitrogen (LN2) temperatures. The study showed that the intrinsic resolution of BGO and the light yield nonproportionality, as a function of energy do not depend on the crystal temperature. High light outputs of 14000 +/- 300 electron-hole pairs and energy resolution of 6.5% +/- 0.2% for 662 keV gamma rays were measured with the 9 mm diameter, 4 mm thick crystals, coupled to large area avalanche photodiodes and cooled down to LN2 temperature. Special attention was paid to analyzing the energy resolution of the escape peaks, which were well separated from the full-energy peaks due to the good energy resolution of BGO at LN2 temperatures and the energy of bismuth KX-rays. The intrinsic energy resolution of the BGO crystal for escape peaks does not show deviations from analysis of total energy absorption photopeaks. This is in spite of the fact that the contributions of X-rays and Auger electron cascade in creation of escape peaks are much smaller than in full-energy peaks. In the small volume crystal, mainly electrons produced in the photoelectric absorption create the escape peaks.
36.	Moszynski, M., et al. (author) Application of large area avalanche photodiodes to study scintillators at liquid nitrogen temperatures 2003 In: Nuclear Instruments and Methods in Physics Research Section A. - 0168-9002 .- 1872-9576. ; 504:03-jan, s. 307-312 Journal article (peer-reviewed)abstract Properties of Large Area Avalanche Photodiodes (LAAPDs) at liquid nitrogen (LN2) temperatures in application to study pure NaI, CsI and BGO scintillators are presented. All the tested crystals exhibited excellent performance at LN2 temperatures reflected by a high light output and very good energy resolution. The study showed that the LAAPD operating at LN2 temperatures is an excellent light readout device for testing different scintillators at low temperatures.
37.	Moszynski, M., et al. (author) Energy resolution and light yield non-proportionality of pure NaI scintillator studied with large area avalanche photodiodes at liquid nitrogen temperatures 2002 In: Nuclear Instruments and Methods in Physics Research Section A. - 0168-9002 .- 1872-9576. ; 486:02-jan, s. 13-17 Journal article (peer-reviewed)abstract The pure NaI crystal has been studied using a Large Area Avalanche Photodiode (LAAPD) at near liquid nitrogen (LN2) temperatures. The study showed a high light output of 44000+/-4000 photons/MeV (ph/MeV), the energy resolution of 5.9 +/- 0.2% for 661.6 keV gamma-rays from a Cs-137 source and a good proportionality of the light yield versus gamma-ray energy. It has been shown also that a cooled LAAPD is an excellent photodetector to study scintillators at near LN2 temperatures.
38.	Moszynski, M., et al. (author) Energy resolution and non-proportionality of the light yield of pure CsI at liquid nitrogen temperatures 2005 In: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 537:02-jan, s. 357-362 Journal article (peer-reviewed)abstract The energy resolution and non-proportionality of the light yield versus gamma-ray energy of pure CsI scintillators directly coupled to Large Area Avalanche Photodiodes (LAAPDs) and cooled down to the liquid nitrogen temperatures have been studied. A very high light output above 100 000 ph/MeV was measured. One of the samples showed nearly proportional light yield response versus energy of gamma-rays yielding energy resolution of 4.3-0.2% for 662 keV gamma-rays from a (CS)-C-137 source. The intrinsic resolution of the crystals versus energy of gamma-rays has been estimated by measurements of the number of primary electron-hole pairs generated in LAAPD by scintillation light. Inspection of the gamma-ray-induced emission spectra of tested samples allows discussing different shapes of non-proportionality curves observed with various samples of CsI.
39.	Moszynski, M., et al. (author) Intrinsic energy resolution of pure NaI studied with large area avalanche photodiodes at liquid nitrogen temperatures 2003 In: Nuclear Instruments and Methods in Physics Research Section A. - 0168-9002 .- 1872-9576. ; 505:02-jan, s. 63-67 Journal article (peer-reviewed)abstract The energy resolution and non-proportionality of the light yield vs gamma-ray energy of pure NaI scintillators directly coupled to Large Area Avalanche Photodiodes (LAAPDs) and cooled down to the liquid nitrogen temperatures have been studied. Large improvements of energy resolution and nearly proportional light yield response have been obtained at very long shaping time constants. Energy resolution of 3.8+/-0.1% for 662 keV gamma-rays from a Cs-137 source was recorded at 50 mus integration time. The intrinsic resolution of the crystal vs energy of gamma-rays has been estimated by measurements of the number of primary electron-hole pairs generated in LAAPD by scintillation light.
40.	Moszynski, M., et al. (author) Study of pure NaI at room and liquid nitrogen temperatures 2003 In: IEEE Transactions on Nuclear Science. - 0018-9499 .- 1558-1578. ; 50:4, s. 767-773 Journal article (peer-reviewed)abstract Three pure NaI crystals grown in different batches by Scionix (The Netherlands) were studied at room and liquid nitrogen temperatures. The room temperature studies performed with photomultiplier readout covered measurements of emission spectra, photoelectrons yield and energy resolution. Moreover, the scintillation light poises were measured by single photon method. Two crystals showed the photoelectron yield of about 1000 phe/MeV measured at room temperature with an XP2020Q photomultiplier. The energy resolution of the 662 keV photopeak was measured to, be about 16% and was limited mainly by a low number of photoelectrons and a large nonproportionality of the light yield. The fast light pulse had the main decay time components of 1 and 5 ns. The high initial photon intensity of the tested NaI crystals revealed a good timing. resolution of about 140 ps obtained for Co-60 gamma-rays. At. liquid nitrogen temperatures the measurements of light yield and energy resolution were performed using An Advanced Photonix, Inc. avalanche photodiode readout A high light output above 80 000 ph/MeV was measured for the best of the tested crystals. The energy resolutions of the 662 kAV photopeak of the three crystals differ a lot, varying from an excellent value of 3.8% to 6.2%. This suggests that the measured, pies energy resolutions depend on the purity of the scintillator samples reflected in the emission spectral The studies that were performed demonstrate the attractive properties of pure NaI at both room and LN2 temperature.
41.	Palacz, M, et al. (author) In beam gamma-ray spectroscopy of very neutron deficient odd-cadmium isotopes 1997 In: Acta Physica Polonica B. - : ACTA PHYSICA POLONICA B, JAGELLONIAN UNIV, INST PHYSICS. - 0587-4254 .- 1509-5770. ; 28:1-2, s. 309-313 Journal article (peer-reviewed)abstract Excited states in the very neutron deficient odd cadmium isotopes Cd-99, Cd-101 and Cd-103 are discussed in terms of the nuclear shell model. Systematics of excited states in Cd99-109 is presented.
42.	Pausch, G, et al. (author) RoSiB - a 4 pi silicon ball for charged-particle detection in EUROBALL 2000 In: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT. - : ELSEVIER SCIENCE BV, AMSTERDAM. - 0168-9002. ; 443:2-3, s. 304-318 Journal article (peer-reviewed)abstract A 4 pi silicon bail for detection and identification of light charged particles in large multidetector gamma-arrays as EUROBALL is presented. The design is based on a N = 42 ball with 12 pentagons and 30 hexagons as used in the GASP array. The absorptive
43.	Pearce, Mark, et al. (author) PoGOLite : A balloon-borne soft gamma-ray polarimeter 2007 In: Proceedings of the 30th International Cosmic Ray Conference, ICRC 2007. - : Universidad Nacional Autonoma de Mexico. ; , s. 479-482 Conference paper (peer-reviewed)abstract Polarized gamma-rays are expected from a wide variety of sources including rotationpowered pulsars, accreting black holes and neutron stars, and jet-dominated active galaxies. Polarization measurements provide a powerful probe of the gamma-ray emission mechanism and the distribution of magnetic and radiation fields around the source. No measurements have been performed in the soft gamma-ray band where non-thermal processes are expected to produce high degrees of polarization. The PoGOLite experiment applies well-type phoswich detector technology to polarization measurements in the 25 - 80 keV energy range. The instrument uses Compton scattering and photoabsorption in an array of 217 phoswich detector cells made of plastic and BGO scintillators, and surrounded by active BGO shields. A prototype of the flight instrument has been tested with polarized gammarays and background generated with radioactive sources. The test results and computer simulations confirm that the instrument can detect 10% polarization of a 200 mCrab source in one 6 hour balloon observation. In flight, targets are constrained to within better than 5% of the field-of-view (~5 degrees squared) in order to maximize the effective detection area during observations. The pointing direction on the sky is determined by an attitude control system comprising star trackers, differential GPS receiver system, gyroscopes, accelerometers and magnetometers which provide correction signals to a reaction wheel and torque motor system. Additionally, the entire polarimeter assembly rotates around its viewing axis to minimize systematic bias during observations. Flights are foreseen to start in 2009- 2010 and will target northern sky sources including the Crab pulsar/nebula, Cygnus X-1, and Hercules X-1. These observations will provide valuable information about the pulsar emission mechanism, the geometry around the black hole, and photon transportation in the strongly magnetized neutron star surface, respectively. Future goals include a long duration balloon flight from the Esrange facility in Northern Sweden to Canada.
44.	Persson, J, et al. (author) In-beam gamma-ray spectroscopy of Cd-102 1997 In: Nuclear Physics A. - : ELSEVIER SCIENCE BV. - 0375-9474 .- 1873-1554. ; 627:1, s. 101-118 Journal article (peer-reviewed)abstract Neutron deficient nuclei close to 100Sn have been studied using the NORDBALL Ge-detector array together with ancillary particle detectors. Evaporation residues from the compound nucleus 108Te were identified with charged particle and neutron detectors. In this paper a considerable extension of the level scheme of the nucleus 102Cd is presented. The strongest cascade of the new level scheme reveals an irregular sequence of dipole transitions above Iπ = 10+ extending up to spin 17. A strongly populated rather regular side band consisting of four quadrupole transitions ranging from spin 9 to spin 17 was also discovered. This band was tentatively assigned negative parity. Shell model calculations were performed and a very good agreement with the experimental results was found. The excited states could successfully be interpreted as neutron particle and proton hole excitations with respect to the doubly closed core 50100Sn50.
45.	Persson, J, et al. (author) New spectroscopic data on Cd-102 1996 In: Acta Physica Polonica B. - : POLISH ACAD SCIENCES INST PHYSICS. - 0587-4254 .- 1509-5770. ; 27:1-2, s. 171-178 Journal article (peer-reviewed)abstract Gamma ray spectroscopy of neutron deficient nuclei close to the doubly magic nucleus Sn-100 has been performed using a heavy-ion reaction and the NORDBALL Ge-detector array. Evaporation residues were identified by means of charged particle and neutron detection. Transitions in 31 different evaporation residues were identified. New results on Cd-102 are presented.
46.	Skeppstedt, O, et al. (author) The EUROBALL neutron wall - design and performance tests of neutron detectors 1999 In: NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION A-ACCELERATORS SPECTROMETERS DETECTORS AND ASSOCIATED EQUIPMENT. - : ELSEVIER SCIENCE BV. ; 421:3, s. 531-541 Journal article (other academic/artistic)abstract The mechanical design of the EUROBALL neutron wall and neutron detectors, and their performance measured with a Cm-246,Cm-248 fission source are described. The array consists of 15 pseudohexaconical detector units subdivided into three, 149 mm high, herme
47.	Sohler, D, et al. (author) Spectroscopy of neutron deficient Ge-65 1997 In: Zeitschrift für Physik A Hadrons and Nuclei. - : Springer Science and Business Media LLC. - 0939-7922 .- 1431-5831. ; 357:3, s. 239-240 Journal article (peer-reviewed)abstract Excited states of 65Ge were populated via the 12C + 58Ni (261 MeV) reaction using the NORDBALL detector array equipped with charged-particle and neutron detector systems for reaction channel separation. On the basis of γγ-coincidence relations and angular distribution ratios a significantly extended level scheme was constructed up to E x = 9 MeV and J π = (33/2−). The low-energy states of the nucleus are discussed in the framework of the interacting boson-fermion model.
48.	Sohler, D, et al. (author) Spectroscopy of neutron deficient Te-108 1998 In: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-6001 .- 1434-601X. ; 3:3, s. 209-211 Journal article (peer-reviewed)abstract The neutron deficient nucleus Te-108 was studied in the Fe-54(Ni-58,2p2n) reaction. A detector system consisting of 4 Euroball cluster detectors, a charged-particle detector ball and a 16 element neutron multiplicity filter was used to detect the emitted particles and gamma rays. A new, significantly extended level scheme was constructed on the basis of gamma gamma-coincidence relations. Spin values for the states were determined from angular distribution ratios. The experimental results are discussed in terms of the shell model.
49.	Sohler, D, et al. (author) Structure of As-68 studied via the C-12(Ni-58,pn) reaction 1998 In: NUCLEAR PHYSICS A. - : ELSEVIER SCIENCE BV. - 0375-9474. ; 644:3, s. 141-161 Journal article (other academic/artistic)abstract Excited states of As-68 nucleus were populated through the C-12(Ni-58,pn) reaction and investigated by in-beam gamma-spectroscopic methods. The NORDBALL detector array equipped with charged particle and neutron detectors was used to detect the evaporated
50.	Sohler, D, et al. (author) Yrast states of the proton drip line nucleus Sb-106 1999 In: PHYSICAL REVIEW C-NUCLEAR PHYSICS. - : AMERICAN PHYSICAL SOC. - 0556-2813. ; 59:3, s. 1324-1327 Journal article (other academic/artistic)abstract Yrast states of Sb-106 have been investigated in the Fe-54(Ni-58, alpha pn) reaction using in-beam gamma-spectroscopic methods and in the Cr-50(Ni-58,pn) reaction performing delayed gamma and conversion electron studies. A new isomeric state was found at

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