Concerning a Possible K = 7/2 Negative Parity Band in 29Si

1971 ◽  
Vol 49 (3) ◽  
pp. 355-359 ◽  
Author(s):  
R. H. Spear ◽  
J. E. Cairns ◽  
R. V. Elliott ◽  
J. A. Kuehner ◽  
A. A. Pilt
Keyword(s):  
Gamma Radiation ◽  
Linear Polarization ◽  
Negative Parity ◽  
Parity Band ◽  
Polarization Studies ◽  
Negative Parity Band

Linear polarization studies of gamma radiation from the reaction 26Mg(α,nγ)29Si show that the parity of the 3.623 MeV [Formula: see text] state is negative, and that the spin and parity of the 5.255 MeV state are [Formula: see text] or [Formula: see text]. A previously reported unique [Formula: see text] assignment for the latter state is not confirmed.

ElectromagneticB(E2)transition strengths along the yrast negative-parity band of113I

2003 ◽  
Vol 67 (5) ◽  
Author(s):  
P. Petkov ◽  
A. Dewald ◽  
A. Fitzler ◽  
T. Klug ◽  
G. de Angelis ◽  
...  
Keyword(s):  
Negative Parity ◽  
Parity Band ◽  
Negative Parity Band

scholarly journals Nuclear Gamma-soft Character in ¹²⁸Ba

2021 ◽  
Vol 3 (3) ◽  
pp. 16-20
Author(s):  
I. Hossain ◽  
Hewa Y. Abdullah ◽  
I. M. Ahmed ◽  
Fadhil I. Sharrad
Keyword(s):  
Energy Level ◽  
Vector Boson ◽  
Negative Parity ◽  
Measured Data ◽  
Interacting Boson Model ◽  
Parity Band ◽  
Boson Model ◽  
Experimental Values ◽  
Negative Parity Band

We report the properties of gamma soft O(6) of 128Ba isotones with neutron N = 72 using Interacting Vector Boson Model (IVBM), interacting Boson Model (IBM-1), Bohr-Mottelson Model (BM), and Doma-El-Gendy (D-G) relation. The first energy level ( ) and ratio  have been investigated which show that 128Ba has gamma-soft character. The curves Eγ/Vs.J of E-GOS of even 128Ba nucleus were compared with the standard curves of vibrational, gamma soft and rotational limits. The staggering factors were studied of available measured data of 128Ba nucleus. The yrast levels of this isotope are calculated by the model of VBMI, IBM-1, BM and D-G and they were compared by measured data. The negative parity band of 128Ba was calculated by IVBM and BM model and compared with experimental values.

Negative-Parity Band inV48

1974 ◽  
Vol 33 (2) ◽  
pp. 105-108 ◽  
Author(s):  
B. Haas ◽  
P. Taras
Keyword(s):  
Negative Parity ◽  
Parity Band ◽  
Negative Parity Band

scholarly journals "Beat" Patterns of Odd-Even Staggering in Octupole Bands of Light Actinides

2019 ◽  
Vol 11 ◽  
Author(s):  
Dennis Bonatsos ◽  
C. Daskaloyannis ◽  
S. B. Drenska ◽  
N. Karoussos ◽  
N. Minkov ◽  
...  
Keyword(s):  
Vector Boson ◽  
Negative Parity ◽  
Interacting Boson Model ◽  
Algebraic Models ◽  
Ground State Band ◽  
Parity Band ◽  
State Band ◽  
Boson Model ◽  
The Difference ◽  
Negative Parity Band

The Δ I = 1 staggering (odd-even staggering) in octupole bands of light actinides. is found to exhibit a "beat" behaviour as a function of the angular momentum J, forcing us to revise the traditional belief that this staggering decreases gradually to, zero and then remains at this zero value. Various algebraic models (spf-Interacting Boson Model, spdf-IBM, Vector Boson Model, Nuclear Vibron Model) predict in their su(3) limits constant staggering for this case, being thus unable to describe the "beat" behaviour. An explanation of the "beat" behaviour is given in terms of two Dunham expansions (expansions in terms of powers of I ( I + 1) ) with slightly different sets of coefficients for the ground state band and the negative parity band, the difference in the values of the coefficients being attributed to Coriolis couplings to other negative parity bands.

High-spin negative parity band in162Er

1976 ◽  
Vol 277 (2) ◽  
pp. 113-115 ◽  
Author(s):  
D. R. Zolnowski ◽  
H. Beuscher ◽  
T. T. Sugihara
Keyword(s):  
High Spin ◽  
Negative Parity ◽  
Parity Band ◽  
Negative Parity Band

Spin–Parity Combinations in 18O

1971 ◽  
Vol 49 (20) ◽  
pp. 2589-2598 ◽  
Author(s):  
R. W. Ollerhead ◽  
G. F. R. Allen ◽  
A. M. Baxter ◽  
J. A. Kuehner
Keyword(s):  
Negative Parity ◽  
Alpha Particles ◽  
Energy Spectra ◽  
Excitation Energies ◽  
Spin Parity ◽  
Unnatural Parity ◽  
Parity Band ◽  
Natural Parity ◽  
Negative Parity Band

Detection of inelastically scattered alpha particles near 180° from the reaction 18O(α,α′)18O has been used to identify natural parity levels in 18O. Energy spectra were recorded for 13 incident energies from 20.0 to 23.4 MeV. Levels at 4.45, 5.09, and 5.25 MeV have been identified as having natural parity, confirming earlier assignments of 1−, 3−, and 2+, respectively. Levels at 5.37 and 5.52 MeV have been identified as having unnatural parity leading to definite assignments of 3+ and 2−, respectively. The spin and parity of the 6.18 MeV level has been restricted to 1− or 2+. Other levels at higher excitation energies have been assigned natural parity, and the implications with regard to the identification of a negative parity band in 18O are discussed.

SHAPE EVOLUTION OF HIGHLY DEFORMED 75Kr AND PROJECTED SHELL MODEL DESCRIPTION

2010 ◽  
Vol 19 (08n09) ◽  
pp. 1754-1762 ◽  
Author(s):  
YING-CHUN YANG ◽  
YANG SUN ◽  
T. TRIVEDI ◽  
R. PALIT ◽  
J. A. SHEIKH
Keyword(s):  
Shell Model ◽  
Negative Parity ◽  
Model Description ◽  
Shape Evolution ◽  
Quadrupole Moments ◽  
Projected Shell Model ◽  
Model Calculations ◽  
High Spin States ◽  
Parity Band ◽  
Insight Into

A study of recently-measured high spin states of 75 Kr is carried out by using the Projected Shell Model. Calculations are performed up to spin I = 33/2 for the positive parity band and I = 27/2 for the negative parity band. Irregularities found in moment of inertia and in the deduced transition quadrupole moments Q t of the two bands are discussed in terms of the alignment of g 9/2 protons. Our study provides an insight into the shape evolution of the well-deformed nucleus 75 kr .

Very long baseline interferometry polarization studies of quasars and active galactic nuclei

1986 ◽  
Vol 64 (4) ◽  
pp. 434-439 ◽  
Author(s):  
J. F. C. Wardle ◽  
D. H. Roberts
Keyword(s):  
Active Galactic Nuclei ◽  
Linear Polarization ◽  
Very Long Baseline Interferometry ◽  
Galactic Nuclei ◽  
Radio Sources ◽  
Long Baseline ◽  
First Results ◽  
Polarization Studies ◽  
Theoretical Issues

We present some first results of a program to map the distribution of linear polarization in compact radio sources with milliarcsecond resolution. We show first-epoch maps of 3C345 and 0735 + 178 and first- and second-epoch maps of OJ287. In general, the polarization is mainly associated with optically thin (jet) components. In the case of OJ287, polarization maps made 1 year apart are strikingly different. We also discuss some of the theoretical issues raised by these observations.

scholarly journals The POLAR gamma-ray burst polarization catalog

2020 ◽  
Vol 644 ◽  
pp. A124 ◽  
Author(s):  
M. Kole ◽  
N. De Angelis ◽  
F. Berlato ◽  
J. M. Burgess ◽  
N. Gauvin ◽  
...  
Keyword(s):  
Linear Polarization ◽  
Gamma Ray ◽  
Integrated Analysis ◽  
Polarization Angle ◽  
Analysis Tool ◽  
Time Resolved ◽  
Gamma Ray Burst ◽  
Polarization Measurements ◽  
Open Questions ◽  
Polarization Studies

Context. Despite over 50 years of research, many open questions remain about the origin and nature of gamma-ray bursts (GRBs). Linear polarization measurements of the prompt emission of these extreme phenomena have long been thought to be key to answering a range of these questions. The POLAR detector was designed to produce the first set of detailed and reliable linear polarization measurements in the 50 − 500 keV energy range. During late 2016 and early 2017, POLAR detected a total of 55 GRBs. The analysis results of 5 of these GRBs have been reported, and were found to be consistent with a low or unpolarized flux. However, previous reports by other collaborations found high levels of linear polarization, including some as high as 90%. Aims. We study the linear polarization for the 14 GRBs observed by POLAR for which statistically robust inferences are possible. Additionally, time-resolved polarization studies are performed on GRBs with sufficient apparent flux. Methods. A publicly available polarization analysis tool, developed within the Multi-Mission Maximum Likelihood framework (3ML), was used to produce statistically robust results. The method allows spectral and polarimetric data from POLAR to be combined with spectral data from the Fermi Gamma-ray Burst Monitor (Fermi-GBM) and the Neil Gehrels Swift Observatory to jointly model the spectral and polarimetric parameters. Results. The time-integrated analysis finds all results to be compatible with low or zero polarization with the caveat that, when time-resolved analysis is possible within individual pulses, we observe moderate linear polarization with a rapidly changing polarization angle. Therefore, time-integrated polarization results, while pointing to lower polarization, are potentially an artifact of summing over the changing polarization signal and thus washing out the true moderate polarization. We therefore caution against overinterpretation of any time-integrated results inferred herein and encourage the community to wait for more detailed polarization measurements from forthcoming missions such as POLAR-2 and LEAP.

scholarly journals OH (1720 MHz) masers: signposts of SNR/molecular cloud interactions

2007 ◽  
Vol 3 (S242) ◽  
pp. 299-306 ◽  
Author(s):  
Crystal L. Brogan
Keyword(s):  
Magnetic Field ◽  
Linear Polarization ◽  
Molecular Cloud ◽  
Supernova Remnant ◽  
Maser Spot ◽  
Current State ◽  
Polarization Studies ◽  
The Magnetic Field ◽  
Field Strengths

AbstractOver the last decade it has been demonstrated that supernova remnant (SNR) OH (1720 MHz) masers are unique tracers of SNR/molecular cloud interactions. Here I briefly review the current state of our observational understanding of these masers including results from recent MERLIN and VLBA full polarization studies of the masers in W28, W44, and W51C. Some of our findings include that (1) in accordance with theory, the linear polarization position angles are either parallel or perpendicular to the plane-of-sky magnetic field determined through other observations; (2) the maser spot sizes are fairly large (~ 1014 cm) and exhibit a core/halo morphology; and (3) while the magnetic field strengths do increase slightly with higher resolution, this effect can be completely explained by spectral/spatial blending.

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