[ { "id": "authors:ts485-sz529", "collection": "authors", "collection_id": "ts485-sz529", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:ZACprd86", "type": "article", "title": "Neutrino-oscillation experiments at the G\u00f6sgen nuclear power reactor", "author": [ { "family_name": "Zacek", "given_name": "G.", "clpid": "Zacek-G" }, { "family_name": "Feilitzsch", "given_name": "F. v.", "clpid": "Feilitzsch-F-v" }, { "family_name": "M\u00f6ssbauer", "given_name": "R. L.", "clpid": "M\u00f6ssbauer-R-L" }, { "family_name": "Oberauer", "given_name": "L.", "clpid": "Oberauer-L" }, { "family_name": "Zacek", "given_name": "V.", "clpid": "Zacek-V" }, { "family_name": "Boehm", "given_name": "F.", "clpid": "Boehm-F" }, { "family_name": "Fisher", "given_name": "P. H.", "clpid": "Fisher-P-H" }, { "family_name": "Gimlett", "given_name": "J. L.", "clpid": "Gimlett-J-L" }, { "family_name": "Hahn", "given_name": "A. A.", "clpid": "Hahn-A-A" }, { "family_name": "Henrikson", "given_name": "H. E.", "clpid": "Henrikson-H-E" }, { "family_name": "Kwon", "given_name": "H.", "clpid": "Kwon-H" }, { "family_name": "Vuilleumier", "given_name": "J. L.", "clpid": "Vuilleumier-J-L" }, { "family_name": "Gabathuler", "given_name": "K.", "clpid": "Gabathuler-K" } ], "abstract": "A search for neutrino oscillations has been conducted at the 2800-MW (thermal) nuclear power reactor in G\u00f6sgen (Switzerland), providing 5\u00d710^20 electron antineutrinos per second. The energy spectrum of the antineutrinos was measured at three distances, 37.9, 45.9, and 64.7 m, from the reactor core. The detection of the neutrinos is based on the reaction \u03bd\u00afe+p\u2192e++n. Roughly 10^4 antineutrinos were registered at each of the three measuring positions. The measured spectra are analyzed in terms of a two-neutrino oscillation model and the results are represented as exclusion plots for the oscillation parameters \u0394m^2 and sin^2(2theta). Two analyses are performed: Analysis A relies exclusively on the data measured at the three different distances; analysis B combines the measured data with additional information, in particular with the reactor antineutrino spectrum as derived from independent \u03b2-spectroscopic measurements. Both analyses show that the data are consistent with the absence of neutrino oscillations, and rule out large regions of parameters (\u0394m2,theta). The resulting limits on the oscillation parameters are \u0394m^2<0.019 eV^2 (90% C.L.) for maximum mixing and sin^2(2theta)<0.21 (90% C.L.) for \u0394m^2>5 eV^2.", "doi": "10.1103/PhysRevD.34.2621", "issn": "2470-0010", "publisher": "Physical Review D", "publication": "Physical Review D", "publication_date": "1986-11-01", "series_number": "9", "volume": "34", "issue": "9", "pages": "2621-2636" }, { "id": "authors:77ejr-h7952", "collection": "authors", "collection_id": "77ejr-h7952", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:KWOprd81", "type": "article", "title": "Search for neutrino oscillations at a fission reactor", "author": [ { "family_name": "Kwon", "given_name": "H.", "clpid": "Kwon-H" }, { "family_name": "Boehm", "given_name": "F.", "clpid": "Boehm-F" }, { "family_name": "Hahn", "given_name": "A. A.", "clpid": "Hahn-A-A" }, { "family_name": "Henrikson", "given_name": "H. E.", "clpid": "Henrikson-H-E" }, { "family_name": "Vuilleumier", "given_name": "J.-L.", "clpid": "Vuilleumier-J-L" }, { "family_name": "Cavaignac", "given_name": "J.-F.", "clpid": "Caviagnac-J-F" }, { "family_name": "Koang", "given_name": "D. H.", "clpid": "Koang-D-H" }, { "family_name": "Vignon", "given_name": "B.", "clpid": "Vignon-B" }, { "family_name": "Feilitzsch", "given_name": "F. v.", "clpid": "Feilitzsch-F-v" }, { "family_name": "M\u00f6ssbauer", "given_name": "R. L.", "clpid": "M\u00f6ssbauer-R-L" } ], "abstract": "The energy spectrum of neutrinos from a fission reactor was studied with the aim of gaining information on neutrino oscillations. The well-shielded detector was set up at a fixed position of 8.76 m from the pointlike core of the Laue-Langevin reactor in an antineutrino flux of 9.8\u00d710^11 cm^-2 s^-1. The target protons in the reaction \u03bd\u0305ep\u2192e+n were provided by liquid-scintillator counters (total volume of 377 l) which also served as positron detectors. The product neutrons moderated in the scintillator were detected by 3He wire chambers. A coincidence signature was required between the prompt positron and the delayed neutron events. The positron energy resolution was 18% full width at half maximum at 0.91 MeV. The signal-to-background ratio was better than 1: 1 between 2 and 6 MeV positron energy. At a counting rate of 1.58 counts per hour, 4890\u00b1180 neutrino-induced events were detected. The shape of the measured positron spectrum was analyzed in terms of the parameters \u03942 and sin22\u03b8 for two-neutrino oscillations. The experimental data are consistent with no oscillations. An upper limit of 0.15 eV2 (90% C.L.) for the mass-squared differences \u03942 of the neutrinos was obtained, assuming maximum mixing of the two-neutrino states. The ratio of the measured to the expected integral yield of positrons assuming no osciliations was determined to be \u222bYexp/\u222bYth=0.955\u00b10.035(statistical)\u00b10.110(systematic).", "doi": "10.1103/PhysRevD.24.1097", "issn": "2470-0010", "publisher": "Physical Review D", "publication": "Physical Review D", "publication_date": "1981-09-01", "series_number": "5", "volume": "24", "issue": "5", "pages": "1097-1111" }, { "id": "authors:yz400-jwv21", "collection": "authors", "collection_id": "yz400-jwv21", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:CLAprl66", "type": "article", "title": "Pseudoquadrupole shift of gamma resonance spectra", "author": [ { "family_name": "Clauser", "given_name": "M. J.", "clpid": "Clauser-M-J" }, { "family_name": "Kankeleit", "given_name": "E.", "clpid": "Kankeleit-E" }, { "family_name": "M\u00f6ssbauer", "given_name": "R. L.", "clpid": "M\u00f6ssbauer-R-L" } ], "abstract": "In most recoilless gamma-ray resonance experiments the magnetic-dipole and electric-quadrupole hyperfine interaction do not cause any shift of the center of gravity of the velocity spectrum. This is usually related to the fact that the trace of the hyperfine-interaction Hamiltonian is zero. Nevertheless a large shift can be caused under proper conditions by a magnetic hyperfine interaction in second order, the so-called \"pseudoquadrupole\" interaction.(1) This paper reports the first observation of the pseudoquadrupole shift of gamma lines.(2)", "doi": "10.1103/PhysRevLett.17.5", "issn": "0031-9007", "publisher": "American Physical Society", "publication": "Physical Review Letters", "publication_date": "1966-07-04", "series_number": "1", "volume": "17", "issue": "1", "pages": "5-8" }, { "id": "authors:5wxs5-j0n35", "collection": "authors", "collection_id": "5wxs5-j0n35", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:BARpr64a", "type": "article", "title": "Electronic shielding by closed shells in salts of thulium", "author": [ { "family_name": "Barnes", "given_name": "R. G.", "clpid": "Barnes-R-G" }, { "family_name": "M\u00f6ssbauer", "given_name": "R. L.", "clpid": "M\u00f6ssbauer-R-L" }, { "family_name": "Kankeleit", "given_name": "E.", "clpid": "Kankeleit-E" }, { "family_name": "Poindexter", "given_name": "J. M.", "clpid": "Poindexter-J-M" } ], "abstract": "Electronic shielding by closed electron shells has been investigated in salts of trivalent thulium, by measuring the temperature dependence of the nuclear quadrupole splitting of the 8.42-keV gamma transition in Tm169. The measurements were performed by using the technique of recoilless nuclear resonance absorption. The nuclear quadrupole interaction was studied for Tm3+ ions in thulium ethyl sulfate, thulium oxide, and thulium trifluoride within a temperature range from 9.6 to 1970\u00b0K. The interpretation of the experimental data in terms of the contributions of distorted closed electron shells to the quadrupole interaction yields values for electronic shielding factors. The results lead to amounts of 10% or less for the atomic Sternheimer factor RQ. The experiments also reveal substantial shielding of the 4f electrons from the crystal electric field, expressed by the shielding factor \u03c32. Values of 250 and 130 are obtained for the ratio (1-\u03b3\u221e)/(1-\u03c32) for thulium ethyl sulfate and thulium oxide, respectively, where \u03b3\u221e is the lattice Sternheimer factor.", "doi": "10.1103/PhysRev.136.A175", "issn": "0031-899X", "publisher": "American Physical Society", "publication": "Physical Review", "publication_date": "1964-10-05", "series_number": "1A", "volume": "136", "issue": "1A", "pages": "A175-A189" }, { "id": "authors:att4t-3e713", "collection": "authors", "collection_id": "att4t-3e713", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:MOSrmp64b", "type": "article", "title": "General aspects of nuclear hyperfine interactions in salts of the rare earths", "author": [ { "family_name": "M\u00f6ssbauer", "given_name": "R. L.", "clpid": "M\u00f6ssbauer-R-L" } ], "abstract": "Most of the experimental studies of recoilless nuclear resonance absorption performed until now have been using the 14.4-keV transition in Fe57. The low energy of this transition, the long lifetime of the relevant nuclear level, the long lifetime of the parent isotope, and, last but not least, the vast number of problems which could be tackled, made Fe57 the favorite isotope in the entire field covered by this conference. In increasing numbers, however, experimental and theoretical studies are progressing which involve nuclear isotopes other than Fe57.", "doi": "10.1103/RevModPhys.36.362", "issn": "0034-6861", "publisher": "American Physical Society", "publication": "Reviews of Modern Physics", "publication_date": "1964-01", "series_number": "1", "volume": "36", "issue": "1", "pages": "362-371" }, { "id": "authors:gazjj-jdh38", "collection": "authors", "collection_id": "gazjj-jdh38", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:MOSrmp64a", "type": "article", "title": "On the theory of resonant scattering of gamma rays by nuclei bound in crystals", "author": [ { "family_name": "M\u00f6ssbauer", "given_name": "R. L.", "clpid": "M\u00f6ssbauer-R-L" }, { "family_name": "Sharp", "given_name": "D. H.", "clpid": "Sharp-D-H" } ], "abstract": "An attempt is made in the present paper to give a\nphysical description of the process in which a gamma\nquantum is resonantly scattered or absorbed by nuclei\nbound in a crystal structure. The discussion includes\na description of the time development of these\nprocesses as well as a critical study of the limits imposed\nupon such a description by the laws of quantum\nmechanics.(1)", "doi": "10.1103/RevModPhys.36.410", "issn": "0034-6861", "publisher": "American Physical Society", "publication": "Reviews of Modern Physics", "publication_date": "1964-01", "series_number": "1", "volume": "36", "issue": "1", "pages": "410-417" }, { "id": "authors:rv4zt-bab95", "collection": "authors", "collection_id": "rv4zt-bab95", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:BARprl63", "type": "article", "title": "Electronic shielding of the crystalline field in thulium ethyl sulfate", "author": [ { "family_name": "Barnes", "given_name": "R. G.", "clpid": "Barnes-R-G" }, { "family_name": "Kankeleit", "given_name": "E.", "clpid": "Kankeleit-E" }, { "family_name": "M\u00f6ssbauer", "given_name": "R. L.", "clpid": "M\u00f6ssbauer-R-L" }, { "family_name": "Poindexter", "given_name": "J. M.", "clpid": "Poindexter-J-M" } ], "abstract": "The method of recoilless nuclear resonance absorption of gamma radiation was employed in investigating the temperature dependence of the nuclear quadrupole interaction in the 8.4-keV level of Tm169 in thulium ethyl sulfate, Tm(C2H5SO4)3\u20229H2O. The experiment reveals a strong influence of electronic shielding resulting from the polarization induced in the closed electron shells by the crystalline electric field.", "doi": "10.1103/PhysRevLett.11.253", "issn": "0031-9007", "publisher": "American Physical Society", "publication": "Physical Review Letters", "publication_date": "1963-09-15", "series_number": "6", "volume": "11", "issue": "6", "pages": "253-255" }, { "id": "authors:5y1ty-vb296", "collection": "authors", "collection_id": "5y1ty-vb296", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161018-154218911", "type": "article", "title": "Recoilless Nuclear Resonance Absorption", "author": [ { "family_name": "M\u00f6ssbauer", "given_name": "R. L.", "clpid": "M\u00f6ssbauer-R-L" } ], "abstract": "The resonant scattering of gamma rays constitutes the nuclear analogue to the well-known optical fluorescence effect. Although its existence was already predicted in 1929 (1) it was actually observed only in 1951 (2). Since then several methods have been developed which led to the observation of resonance scattering or absorption in a number of first excited nuclear states. A major breakthrough took place in 1958 when the phenomenon of recoilless nuclear resonance absorption was discovered (3). This new absorption effect provided a means for the elimination of the energy losses by recoil, these being the most serious obstacle for the observation of nuclear resonance absorption or scattering. Simultaneously gamma lines of utmost narrowness became available. It is this particular feature which opened a wide range of applications for the new effect, in such fields as nuclear physics, solid state physics, and relativity, and made possible investigations which could not even be considered only a few years ago.\n\nThis article is an account of the major features of the recoilless nuclear resonance absorption: the treatment emphasizes the general aspects, and the selection of references was restricted accordingly. For a complete list of references the reader is referred to the compilation of Frauenfelder (4) and to the proceedings of two conferences (5, 6) which were solely devoted\nto the subject under discussion.", "doi": "10.1146/annurev.ns.12.120162.001011", "issn": "0066-4243", "publisher": "Annual Reviews", "publication": "Annual Review of Nuclear Science", "publication_date": "1962-12", "volume": "12", "pages": "123-152" }, { "id": "authors:ddw5j-6r603", "collection": "authors", "collection_id": "ddw5j-6r603", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151125-100143441", "type": "article", "title": "Recoilless Nuclear Resonance Absorption of Gamma Radiation: A new principle yields gamma lines of extreme narrowness for measurements of unprecedented accuracy", "author": [ { "family_name": "M\u00f6ssbauer", "given_name": "Rudolf L.", "clpid": "M\u00f6ssbauer-R-L" } ], "abstract": "A new principle yields gamma lines of extreme narrowness for measurements of unprecedented accuracy.", "doi": "10.1126/science.137.3532.731", "issn": "0036-8075", "publisher": "American Association for the Advancement of Science", "publication": "Science", "publication_date": "1962-09-07", "series_number": "3532", "volume": "137", "issue": "3532", "pages": "731-738" } ]