scholarly journals Charmonium and light hadron spectroscopy

2014 ◽  
Vol 31 ◽  
pp. 1460292
Author(s):  
Chengping Shen
Keyword(s):  
Mass Spectrum ◽  
Mass Spectra ◽  
Mass Region ◽  
Resonance Parameters ◽  
Hadron Spectroscopy ◽  
Light Hadron ◽  
Low Mass

In this report I review some results on the charmonium and light hadron spectroscopy mainly from BESIII and Belle experiments. For the charmonium, the contents include the observation of ψ(4040)/ψ(4160) → ηJ/ψ, the measurements of the ηc/ηc(2S) resonance parameters and their decays, the evidence of the ψ2(13D2) state in the χc1γ mass spectrum. For the light hadron spectroscopy, the contents include the X(1835) research in e+e- → J/ψ + X(1835) and γγ → η′π+π- processes, and the analysis of the ηη, ωϕ, ϕϕ and ωω mass spectra in low mass region.

scholarly journals RECENT RESULTS ON LIGHT HADRON SPECTROSCOPY AT BESIII

2011 ◽  
Vol 02 ◽  
pp. 183-187
Author(s):  
◽  
Y. CHEN
Keyword(s):  
Mass Spectrum ◽  
Matrix Element ◽  
Direct Measurement ◽  
International Workshop ◽  
Charm Physics ◽  
Hadron Spectroscopy ◽  
Threshold Enhancement ◽  
Light Hadron ◽  
The Matrix ◽  
Near Threshold

Several measurements on light hadron spectroscopy have been achieved with Beijing Spectrometry III (BESIII). BESII results such as a near threshold enhancement on the [Formula: see text] invariants mass spectrum namely X(1860) and a resonance X(1835) have been confirmed with 225 million J/ψ data accumulated from June 12, 2009 to July 28, 2009. Along with some other preliminary BESIII results including observations of X(1870), X(2120) and X(2370); the first direct measurement of a0(980)/f0(980) mixing; and an improved measurement on the matrix element of decay η′ → ππη have been reported at the 4th international workshop on charm physics.

Di-lepton production in heavy-ion collisions and the QCD phase diagram

Open Physics ◽  
2012 ◽  
Vol 10 (6) ◽  
Author(s):  
Yifei Zhang ◽  
Haojie Xu ◽  
Wangmei Zha ◽  
Qun Wang
Keyword(s):  
Phase Diagram ◽  
Mass Spectra ◽  
Heavy Ion ◽  
Mass Region ◽  
Lepton Production ◽  
Qcd Phase Diagram ◽  
Ion Collisions ◽  
200 Gev ◽  
Star Experiment ◽  
Low Mass

AbstractWe reproduce di-electron spectra in the region of 0 < m e+e < 4 GeV in both minimum bias and central Au+Au collisions at $\sqrt {s_{NN} } $ = 200 GeV measured by the STAR experiment. A cocktail simulation, incorporating STAR acceptance and detector responses, is able to describe the “enhancement” of the low mass region by including an in-medium modification of vector mesons and a thermal di-lepton calculation. We also predict the di-lepton mass spectra in RHIC lower energies via an extrapolation method. The evolution of Di-lepton mass spectra, effective temperature, and possible medium modifications versus colliding energies are studied to explore the QCD phase diagram.

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

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.

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

Proteomes ◽  
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.

EVOLUTION OF SHELL STRUCTURE IN NUCLEI

2011 ◽  
Vol 20 (08) ◽  
pp. 1663-1675 ◽  
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.

scholarly journals On Mass Spectra of Primordial Black Holes

2021 ◽  
Vol 8 ◽  
Author(s):  
Alexander A. Kirillov ◽  
Sergey G. Rubin
Keyword(s):  
Black Holes ◽  
Mass Spectrum ◽  
Mass Spectra ◽  
Scalar Fields ◽  
Small Mass ◽  
Primordial Black Holes ◽  
Classical Motion ◽  
Multiple Production ◽  
Analytical Formulas ◽  
Intrinsic Feature

Evidence for the primordial black holes (PBH) presence in the early Universe renews permanently. New limits on their mass spectrum challenge existing models of PBH formation. One of the known models is based on the closed walls collapse after the inflationary epoch. Its intrinsic feature is the multiple production of small mass PBH which might contradict observations in the nearest future. We show that the mechanism of walls collapse can be applied to produce substantially different PBH mass spectra if one takes into account the classical motion of scalar fields together with their quantum fluctuations at the inflationary stage. Analytical formulas have been developed that contain both quantum and classical contributions.

scholarly journals Spectrometric Study of the Nitrile-Ketenimine Tautomerism

2009 ◽  
Vol 2009 ◽  
pp. 1-18 ◽  
Author(s):  
Hebe Saraví Cisneros ◽  
Sergio Laurella ◽  
Danila L. Ruiz ◽  
Agustín Ponzinibbio ◽  
Patricia E. Allegretti ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Nuclear Magnetic Resonance ◽  
Mass Spectrum ◽  
Magnetic Resonance ◽  
Mass Spectra ◽  
Spectrometric Study ◽  
Mass Spectral ◽  
Ion Fragmentation ◽  
Nuclear Magnetic Resonance Spectra ◽  
Amination Product

Mass spectrometry is used to evaluate the occurrence of the nitrile-ketenimine tautomerism. Mass spectra of two differently substituted nitriles, ethyl-4,4-dicyano-3-methyl-3-butenoate and diethyl-2-cyano-3-methyl-2-pentenodiate are examined looking for common mass spectral behaviors. Ion fragmentation assignments for specific tautomers allow to predict the presence of the corresponding structures. Additionally, the mass spectrum and nuclear magnetic resonance spectra of ethyl-4,4-dicyano-2,2-diethyl-3-methyl-3-butenoate and that of the corresponding amination product support the occurrence of the ketenimine tautomer in the equilibrium.

scholarly journals Recent BaBar results in light hadron spectroscopy

2019 ◽  
Vol 212 ◽  
pp. 04006
Author(s):  
Evgeny Kozyrev ◽  
Evgeny Solodov ◽  
Vladimir Druzhinin
Keyword(s):  
Center Of Mass ◽  
Mass Energy ◽  
Full Data ◽  
Data Set ◽  
Hadron Spectroscopy ◽  
Center Of Mass Energy ◽  
Two Photon ◽  
Light Hadron ◽  
Photon Process ◽  
Babar Experiment

We report the results on the channels e+e−→ π+π−π0π0π0(η), e+e−→ π+π−η. Also we present the study of the two-photon process e+e−→ e+e−η' in the double-tag mode. The results for the form factor are compared with the predictions based on pQCD and VMD. The results are obtained by using the full data set of about 470 fb−1 collected by the BABAR experiment at the PEP-II e+e−collider at a center-of-mass energy of about 10.6 GeV.

scholarly journals Studies of the resonance components in the $$B_s$$ decays into charmonia plus kaon pair

2019 ◽  
Vol 79 (9) ◽  
Author(s):  
Zhou Rui ◽  
Ya Li ◽  
Hong Li
Keyword(s):  
Mass Spectra ◽  
Branching Ratios ◽  
Mass Region ◽  
Lhcb Collaboration ◽  
High Mass ◽  
Mass Window ◽  
Resonant Structures ◽  
Three Body ◽  
Near Future ◽  
Existing Data

Abstract In this work, the decays of $$B_s$$Bs meson to a charmonium state and a $$K^+K^-$$K+K- pair are carefully investigated in the perturbative QCD approach. Following the latest fit from the LHCb experiment, we restrict ourselves to the case where the produced $$K^+K^-$$K+K- pair interact in isospin zero S, P, and D wave resonances in the kinematically allowed mass window. Besides the dominant contributions of the $$\phi (1020)$$ϕ(1020) resonance in the P-wave and $$f_2'(1525)$$f2′(1525) in the D-wave, other resonant structures in the high mass region as well as the S-wave components are also included. The invariant mass spectra for most of the resonances in the $$B_s\rightarrow J/\psi K^+K^-$$Bs→J/ψK+K- decay are well reproduced. The obtained three-body decay branching ratios can reach the order of $$10^{-4}$$10-4, which seem to be accessible in the near future experiments. The associated polarization fractions of those vector-vector and vector-tensor modes are also predicted, which are compared with the existing data from the LHCb Collaboration.

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