Theoretical spin assignment and study of the A~100 140 superdeformed mass region by using ab formula

The nuclear softness formula has been applied to obtain the band head spin ([Formula: see text]) of 7 superdeformed rotational bands ([Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text] and [Formula: see text]) in A[Formula: see text]60−80 mass region. To obtain the band head spin ([Formula: see text]) of 7 superdeformed rotational bands in A[Formula: see text]60−80 mass region least square fitting method is used. The parameters are extracted by fitting the intraband transition energies in the nuclear softness formula from where the root mean deviation (RMD) between the calculated and the observed transition energies are obtained. The calculated transition energies are in good agreement with the experimental transition energies whenever exact band head spin ([Formula: see text]) is assigned. The calculated values of dynamic moment of inertia and its variation with rotational frequency for seven superdeformed rotational bands in A[Formula: see text]60−80 mass region are also studied. Hence, it is suggested that the nuclear softness formula works very well in A[Formula: see text]60−80 mass region.

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On the question of spin assignment and quantized alignment in the A~ 100-140 superdeformed mass region

Arab Journal of Nuclear Sciences and Applications ◽

10.21608/ajnsa.2019.6023.1133 ◽

2019 ◽

Vol 52 (3) ◽

pp. 98-114

Author(s):

Ahmed Shalaby

Keyword(s):

Mass Region ◽

Spin Assignment

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Detection capability of Migdal effect for argon and xenon nuclei with position sensitive gaseous detectors

Progress of Theoretical and Experimental Physics ◽

10.1093/ptep/ptaa162 ◽

2020 ◽

Author(s):

Kiseki D Nakamura ◽

Kentaro Miuchi ◽

Shingo Kazama ◽

Yutaro Shoji ◽

Masahiro Ibe ◽

...

Keyword(s):

Gamma Rays ◽

Experimental Approach ◽

Isotope Separation ◽

Mass Region ◽

Background Rate ◽

Argon Gas ◽

Low Mass ◽

Position Sensitive ◽

Set Up ◽

Direct Dark Matter

Abstract Migdal effect is attracting interests because of the potential to enhance the sensitivities of direct dark matter searches to the low mass region. In spite of its great importance, the Migdal effect has not been experimentally observed yet. A realistic experimental approach towards the first observation of the Migdal effect in the neutron scattering was studied with Monte Carlo simulations. In this study, potential background rate was studied together with the event rate of the Migdal effect by a neutron source. It was found that a table-top sized ~ (30cm)3 position-sensitive gaseous detector filled with argon or xenon target gas can detect characteristic signatures of the Migdal effect with sufficient rates (O(102 ~ 103) events/day). A simulation result of a simple experimental set-up showed two significant background sources, namely the intrinsic neutrons and the neutron induced gamma-rays. It is found that the intrinsic neutron background rate for the argon gas is acceptable level and some future study for the reduction of the gamma-rays from the laboratory would make the observation of the Migdal effect possible. The background for the xenon gas, on the other hand, is found to be much more serious than for the argon gas. Future works on the isotope separation as well as the reduction of the gamma-rays from the detector and laboratory will be needed before the Migdal effect observation for xenon gas case.

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Small Mass but Strong Information: Diagnostic Ions Provide Crucial Clues to Correctly Identify Histone Lysine Modifications

Proteomes ◽

10.3390/proteomes9020018 ◽

2021 ◽

Vol 9 (2) ◽

pp. 18

Author(s):

Alaa Hseiky ◽

Marion Crespo ◽

Sylvie Kieffer-Jaquinod ◽

François Fenaille ◽

Delphine Pflieger

Keyword(s):

Amino Acid ◽

Small Mass ◽

Mass Region ◽

Amino Acid Sequences ◽

Lysine Modification ◽

Lysine Residues ◽

Two Factors ◽

Low Mass ◽

Diagnostic Ions

(1) Background: The proteomic analysis of histones constitutes a delicate task due to the combination of two factors: slight variations in the amino acid sequences of variants and the multiplicity of post-translational modifications (PTMs), particularly those occurring on lysine residues. (2) Methods: To dissect the relationship between both aspects, we carefully evaluated PTM identification on lysine 27 from histone H3 (H3K27) and the artefactual chemical modifications that may lead to erroneous PTM determination. H3K27 is a particularly interesting example because it can bear a range of PTMs and it sits nearby residues 29 and 31 that vary between H3 sequence variants. We discuss how the retention times, neutral losses and immonium/diagnostic ions observed in the MS/MS spectra of peptides bearing modified lysines detectable in the low-mass region might help validate the identification of modified sequences. (3) Results: Diagnostic ions carry key information, thereby avoiding potential mis-identifications due to either isobaric PTM combinations or isobaric amino acid-PTM combinations. This also includes cases where chemical formylation or acetylation of peptide N-termini artefactually occurs during sample processing or simply in the timeframe of LC-MS/MS analysis. Finally, in the very subtle case of positional isomers possibly corresponding to a given mass of lysine modification, the immonium and diagnostic ions may allow the identification of the in vivo structure.

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Charge exchange reactions on medium and heavy mass targets at intermediate energies

Modern Physics Letters A ◽

10.1142/s0217732320500455 ◽

2019 ◽

Vol 35 (08) ◽

pp. 2050045

Author(s):

Pardeep Singh ◽

Monika Singh ◽

Neha Rani

Keyword(s):

Charge Exchange ◽

Cross Sections ◽

Energy Charge ◽

Impulse Approximation ◽

Mass Region ◽

Intermediate Energy ◽

Exchange Reactions ◽

Plane Wave Impulse Approximation ◽

Text Type ◽

Intermediate Energies

The nuclear isotopic structure can be understood easily via the intermediate-energy charge exchange reactions of (p, n) and [Formula: see text]He, [Formula: see text] type. In the current contribution, we present some results for charge exchange reactions induced by 3He on targets lying in mass region [Formula: see text] within the theoretical framework of plane wave impulse approximation (PWIA) and distorted wave impulse approximation (DWIA). Here, the recoil effects in PWIA have also been considered. Particularly, the angular distributions and the unit cross-sections have been calculated and compared with the available data. Further, the importance of inclusion of the exchange contribution in these reactions is also considered, which eventually enhance the matching with data.

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EVOLUTION OF SHELL STRUCTURE IN NUCLEI

International Journal of Modern Physics E ◽

10.1142/s0218301311019581 ◽

2011 ◽

Vol 20 (08) ◽

pp. 1663-1675 ◽

Cited By ~ 4

Author(s):

A. BHAGWAT ◽

Y. K. GAMBHIR

Keyword(s):

Shell Structure ◽

Crucial Role ◽

Field Model ◽

Mean Field ◽

Mass Region ◽

The Other ◽

Mean Field Model ◽

Relativistic Mean Field ◽

Shell Closures ◽

Low Mass

Systematic investigations of the pairing and two-neutron separation energies which play a crucial role in the evolution of shell structure in nuclei, are carried out within the framework of relativistic mean-field model. The shell closures are found to be robust, as expected, up to the lead region. New shell closures appear in low mass region. In the superheavy region, on the other hand, it is found that the shell closures are not as robust, and they depend on the particular combinations of neutron and proton numbers. Effect of deformation on the shell structure is found to be marginal.

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Cumulative yields of stable and long-lived isotopes of tin in neutron-induced fission

Canadian Journal of Physics ◽

10.1139/p83-193 ◽

1983 ◽

Vol 61 (11) ◽

pp. 1490-1497 ◽

Cited By ~ 5

Author(s):

K. J. R. Rosman ◽

J. R. De Laeter ◽

J. W. Boldeman ◽

H. G. Thode

Keyword(s):

Stable Isotopes ◽

Fine Structure ◽

Fission Product ◽

Mass Spectrometer ◽

Smooth Curve ◽

Mass Region ◽

Neutron Fission ◽

Source Mass ◽

Induced Fission ◽

Fission Yields

The relative cumulative fission yields of the six stable isotopes of tin (117Sn,118Sn, 119Sn, 120Sn, 122Sn, and 124Sn) and the long-lived isotope 126Sn have been measured in the thermal and epicadium neutron fission of 233U and 235U, and the epicadium neutron fission of 238U. Nanogram-sized fission product tin samples were extracted from irradiated uranium samples and analyzed in a solid source mass spectrometer. In each case a smooth curve can be drawn through the yield points of the seven isotopes of tin. There is, therefore, no evidence of "fine structure" in the 117 ≤ A ≤ 126 portion of the symmetric mass region.

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