The 2506–2159 keV transition in 60Ni following beta decay of 60Co

1977 ◽  
Vol 55 (2) ◽  
pp. 142-146 ◽  
Author(s):  
B. A. Logan ◽  
W. R. Dixon ◽  
R. S. Storey ◽  
A. Ljubičić
Keyword(s):  
Beta Decay ◽  
Confidence Limit ◽  
Upper Limit ◽  
Γ Ray ◽  
Coincidence Arrangement

A Ge(Li)–NaI(Tl) coincidence arrangement has been used to verify the presence of a 347 keV γ ray following the beta decay of 60Co. This γ ray is identified as the 2506 → 2159 keV transition in 60Ni. The intensity was measured to be (6.9 ± 1.0) × 10−5 per beta disintegration of 60Co. An upper limit of 1.2 × 10−5 per beta disintegration (95% confidence limit) was obtained for the 2626 → 2159 keV transition in 60Ni.

Double-beta decay and resonances in the nucleus

1978 ◽  
Vol 56 (4) ◽  
pp. 399-402 ◽  
Author(s):  
Charles Picciotto
Keyword(s):  
Quark Model ◽  
Beta Decay ◽  
Numerical Results ◽  
Double Beta Decay ◽  
Electron Neutrino ◽  
Present Calculation ◽  
Upper Limit ◽  
Underlying Mechanisms

Double-beta decay half-lives are calculated with the assumption that the emission of electron–neutrino pairs occurs via a Δ(1232) resonance in the nucleus. Numerical results are obtained with a quark model for the hadrons. By assuming that total rates are produced by a combination of neutrinoless and two-nuetrino modes, a lepton-nonconservation parameter η ~ 10−5 is obtained. Although the actual modes of decay and underlying mechanisms are undetermined, the present calculation can be used to obtain an upper limit for the probability admixture of resonances in the nucleus of a few percent.

K-shell autoionization in the beta decay of 95Nb

1976 ◽  
Vol 54 (20) ◽  
pp. 2024-2027 ◽  
Author(s):  
M. Jurčević ◽  
A. Ljubičić ◽  
Z. Krečak ◽  
K. Ilakovac
Keyword(s):  
Theoretical Result ◽  
Beta Decay ◽  
Coincidence Method ◽  
X Ray ◽  
A Value ◽  
Γ Ray ◽  
Recent Theoretical Result

The X-ray–γ-ray coincidence method was applied to determine the probability of K-shell autoionization in the beta decay of 95Nb. A value of PK = (3.4 ± 0.4) × 10−4 was obtained. This result is in agreement with the recent theoretical result obtained by Law and Campbell.

Upper limit onTnonconserving tensor couplings in nuclear beta decay

1985 ◽  
Vol 31 (6) ◽  
pp. 2218-2221 ◽  
Author(s):  
M. Skalsey ◽  
M. S. Hatamian
Keyword(s):  
Beta Decay ◽  
Nuclear Beta Decay ◽  
Upper Limit

scholarly journals Search for γ-ray emission from superluminous supernovae with the Fermi-LAT

2018 ◽  
Vol 611 ◽  
pp. A45 ◽  
Author(s):  
N. Renault-Tinacci ◽  
K. Kotera ◽  
A. Neronov ◽  
S. Ando
Keyword(s):  
Neutron Stars ◽  
Confidence Level ◽  
Compact Object ◽  
Photon Spectrum ◽  
Systematic Search ◽  
Large Area ◽  
Rotation Periods ◽  
Upper Limit ◽  
Upper Limits ◽  
Γ Ray

We present the first individual and stacking systematic search for γ-ray emission in the GeV band in the directions of 45 superluminous supernovae (SLSNe) with the Fermi Large Area Telescope (LAT). No excess of γ-rays from the SLSN positions was found. We report γ-ray luminosity upper limits and discuss the implication of these results on the origin of SLSNe and, in particular, the scenario of central compact object-aided SNe. From the stacking search, we derived an upper limit at 95% confidence level to the γ-ray luminosity (above 600 MeV) Lγ < 9.1 × 1041 erg s−1 for an assumed E−2 photon spectrum for our full SLSN sample. We conclude that the rate of the neutron stars born with millisecond rotation periods P ≲ 2 ms and B ~ 1012−13 G must be lower than the rate of the observed SLSNe. The luminosity limits obtained on individual sources are also constraining: in particular, SN2013fc, CSS140222, SN2010kd, and PTF12dam can only be born with millisecond periods if B ≲ 1013 G.

scholarly journals Searching for Neutrinoless Double-Beta Decay of130Te with CUORE

2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
D. R. Artusa ◽  
F. T. Avignone ◽  
O. Azzolini ◽  
M. Balata ◽  
T. I. Banks ◽  
...  
Keyword(s):  
Beta Decay ◽  
Energy Resolution ◽  
Confidence Level ◽  
Half Life ◽  
Average Energy ◽  
Neutrinoless Double Beta Decay ◽  
Lepton Number ◽  
Double Beta Decay ◽  
Current Status ◽  
Upper Limit

Neutrinoless double-beta (0νββ) decay is a hypothesized lepton-number-violating process that offers the only known means of asserting the possible Majorana nature of neutrino mass. The Cryogenic Underground Observatory for Rare Events (CUORE) is an upcoming experiment designed to search for 0νββdecay of130Te using an array of 988 TeO2crystal bolometers operated at 10 mK. The detector will contain 206 kg of130Te and have an average energy resolution of 5 keV; the projected 0νββdecay half-life sensitivity after five years of livetime is 1.6 × 1026 y at 1σ(9.5 × 1025 y at the 90% confidence level), which corresponds to an upper limit on the effective Majorana mass in the range 40–100 meV (50–130 meV). In this paper, we review the experimental techniques used in CUORE as well as its current status and anticipated physics reach.

Levels in 89Rb Populated by the Beta Decay of 89Kr

1972 ◽  
Vol 50 (22) ◽  
pp. 2741-2752 ◽  
Author(s):  
W. F. S. Poehlman ◽  
B. Singh ◽  
M. W. Johns
Keyword(s):  
Excited States ◽  
Beta Decay ◽  
Gamma Rays ◽  
Large Volume ◽  
Ground State ◽  
Level Scheme ◽  
Gamma Coincidence ◽  
Coincidence Data ◽  
Coincidence Arrangement

The decay of 3.2 min 89Kr has been investigated with small and large volume Ge(Li) detectors used singly and in a dual parameter coincidence arrangement. A total of 162 gamma rays are identified with the decay of this isotope, 120 of which are placed in a level scheme on the basis of gamma–gamma coincidence evidence and the energy differences between established levels. Levels at 220.9, 497.7, 577.3, 586.1, 930.7, 931.5, 997.6, 1195.5, 1324.6, 1530.1, 1533.6, 1694.1, 1822.1, 1998.9, 2160.5, 2401.5, 2598.5, 2867.2, 3099.7, 3329.9, 3363.1, 3372.1, 3534.1, 3719.3, 4145.1, 4217.4, 4340.9, and 4487.5 keV are well established by coincidence data and many energy sums. The levels proposed at 2783.4, 3429.7, 3456.6, 3978.4, 4058.4, and 4406.5 keV are less securely established. The most probable spins of the ground state and the first two excited states arc 3/2−. 5/2− and 1/2− respectively. Improved energies and intensities of the gamma rays from the decay of 15 min 89Rb have also been determined.

Low background study of the neutrinoless double beta decay of 76-GE and upper limit for neutrino mass

1984 ◽  
Vol 138 (4) ◽  
pp. 301-303 ◽  
Author(s):  
A. Forster ◽  
H. Kwon ◽  
J.K. Markey ◽  
F. Boehm ◽  
H.E. Henrikson
Keyword(s):  
Beta Decay ◽  
Neutrino Mass ◽  
Neutrinoless Double Beta Decay ◽  
Double Beta Decay ◽  
Low Background ◽  
Upper Limit

scholarly journals Very high energy γ-ray emission from two blazars of unknown redshift and upper limits on their distance

2020 ◽  
Vol 494 (4) ◽  
pp. 5590-5602
Author(s):  
H Abdalla ◽  
R Adam ◽  
F Aharonian ◽  
F Ait Benkhali ◽  
E O Angüner ◽  
...  
Keyword(s):  
Confidence Level ◽  
High Energy ◽  
Bl Lac Objects ◽  
Upper Limit ◽  
Upper Limits ◽  
Bl Lac ◽  
Very High Energy ◽  
Stereoscopic System ◽  
Γ Ray ◽  
Very High

ABSTRACT We report on the detection of very high energy (VHE; E &gt; 100 GeV) γ-ray emission from the BL Lac objects KUV 00311−1938 and PKS 1440−389 with the High Energy Stereoscopic System (H.E.S.S.). H.E.S.S. observations were accompanied or preceded by multiwavelength observations with Fermi/LAT, XRT and UVOT onboard the Swift satellite, and ATOM. Based on an extrapolation of the Fermi/LAT spectrum towards the VHE γ-ray regime, we deduce a 95 per cent confidence level upper limit on the unknown redshift of KUV 00311−1938 of $z$ &lt; 0.98 and of PKS 1440−389 of $z$ &lt; 0.53. When combined with previous spectroscopy results, the redshift of KUV 00311−1938 is constrained to 0.51 ≤ $z$ &lt; 0.98 and of PKS 1440−389 to 0.14 ⪅ $z$ &lt; 0.53.

scholarly journals X-ray and Radio Studies of the candidate Millisecond Pulsar Binary 4FGL J0935.3+0901

2021 ◽  
Author(s):  
冬 郑 ◽  
Zhong-Xiang Wang ◽  
Yi Xing ◽  
Jithesh Vadakkumthani
Keyword(s):  
Power Law ◽  
Distinctive Feature ◽  
Optical Spectrum ◽  
Emission Lines ◽  
Millisecond Pulsar ◽  
X Ray ◽  
Upper Limit ◽  
Radio Pulsation ◽  
Radio Studies ◽  
Γ Ray

Abstract 4FGL J0935.5+0901, a γ-ray source recently identified as a candidate redback-type millisecond pulsar binary (MSP), shows an interesting feature of having double-peaked emission lines in its optical spectrum. The feature would further suggest the source as a transitional MSP system in the sub-luminous disk state. We have observed the source with XMM-Newton and Five-hundred-meter Aperture Spherical radio Telescope (FAST) at X-ray and radio frequencies respectively for further studies. From the X-ray observation, a bimodal count-rate distribution, which is a distinctive feature of the transitional MSP systems, is not detected, while the properties of X-ray variability and power-law spectrum are determined for the source. These results help establish the consistency of it being a redback in the radio pulsar state. However no radio pulsation signals are found in the FAST observation, resulting an upper limit on the flux density of ∼ 4 µJy. Implications of these results are discussed.

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