Possible Indication of Narrow Baryonic Resonances Produced in the 1720-1790 MeV Mass Region

B. Tatischeff; J. Yonnet; M. Boivin; M. P. Comets; P. Courtat; R. Gacougnolle; Y. Le Bornec; E. Loireleux; M. MacCormick; F. Reide; N. Willis

doi:10.1080/01422410410001699231

arXiv · nucl-ex/0411008

Possible Indication of Narrow Baryonic Resonances Produced in the 1720-1790 MeV Mass Region

B. Tatischeff·J. Yonnet·M. Boivin·M. P. Comets·P. Courtat·R. Gacougnolle·Y. Le Bornec·E. Loireleux·M. MacCormick·F. Reide·N. Willis

View original source ↗Read source document ↗Export metadata ↓

Abstract

Signals of two narrow structures at M=1747 MeV and 1772 MeV were observed in the invariant masses M_{pX} and M_{π^{+}X} of the pp->ppX and pp->pπ^{+}X reactions respectively. Many tests were made to see if these structures could have been produced by experimental artefacts. Their small widths and the stability of the extracted masses lead us to conclude that these structures are genuine and may correspond to new exotic baryons. Several attempts to identify them, including the possible "missing baryons" approach, are discussed.

Explore related subjects

nucl-ex

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

B. Tatischeff, J. Yonnet, M. Boivin, M. P. Comets, P. Courtat, R. Gacougnolle, Y. Le Bornec, E. Loireleux, M. MacCormick, F. Reide, N. Willis. 2004-11-05. Possible Indication of Narrow Baryonic Resonances Produced in the 1720-1790 MeV Mass Region. https://doi.org/10.1080/01422410410001699231

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Precise and accurate nuclear electric quadrupole moment of $^{223}$Ra from molecular spectroscopy

Nuclear electric quadrupole moments of unstable isotopes are commonly extracted from laser spectroscopy of the atomic hyperfine structure, where the accuracy is limited to the several-percent level by the available electric-field-gradient (EFG) calculations. In this study, we determine the spectroscopic quadrupole moment of $^{223}$Ra (half-life $t_{1/2} = 11.4$ d) from hyperfine-resolved collinear resonance ionization spectroscopy of the radioactive molecule $^{223}$Ra$^{19}$F. The $X\,^2Σ^+$ electronic ground state of RaF provides a large axial EFG at the radium nucleus that can be calculated with relativistic coupled-cluster theory to sub-percent accuracy. Together with a three-fold improvement in spectral resolution over previous fast-beam measurements of radioactive molecules, this yields $Q_s = +1.211(7)_\mathrm{stat}(2)_\mathrm{syst}(5)_\mathrm{theo}\,e\mathrm{b}$ for $^{223}$Ra with a total uncertainty of 0.73%, approximately three times better than atomic and ionic determinations. This result demonstrates that molecular spectroscopy can provide access to the electromagnetic structure of unstable nuclei with a precision competitive with, and in favorable cases better than, atomic spectroscopy, and may thus be envisioned for studies beyond the limitations of current radioactive-atom experiments.

nucl-ex↗

arXiv2026

Cumulative protons and pions at the intermediate energies in the FRAGM experiment

One of the important research objectives of the FRAGM experiment operating at the TWAC heavy-ion accelerator-storage complex was the study of particle production in the cumulative region. Differential cross sections were measured for the production of pions - resulting from the fragmentation of carbon nuclei at an energy of 3.2 GeV/nucleon, as well as protons with energy range from 300 to 2000 MeV/nucleon at an angle of 3.5 degrees relative to the incident ion beam. The parameterization of cumulative effect used in experiments investigating nucleus-nucleus interactions is discussed. It is shown, that the energy dependencies of these parameters are analogous to those observed in nucleon-nucleus interactions and indicate the presence of nuclear scaling behavior.

nucl-ex↗

arXiv2026

Investigation of Medium Modifications to $^{12}$C Structure Functions in the Resonance Region

We present results from a high precision experimental study of the nuclear modification of the longitudinal ($F_L$) to transverse ($F_1$) structure function ratio for bound nucleons in the resonance region. The inclusive electron scattering cross sections were measured in Jefferson Lab Experimental Hall C on carbon and deuterium nuclei for a large range of kinematics, allowing for separations of the longitudinal and transverse structure functions to be performed at a range of four-momentum transfer values $0.5 \le Q^2 \le$ 3.75 GeV$^2$. In contrast to the significant body of measurements of the nuclear modification of the $F_2$ structure function in the deep inelastic scattering region, there is very little on $F_L$ and $R = F_L / 2xF_1$ in the region of the nucleon resonances. In this paper we present measurements of the nuclear effect on $R$ for $^{12}$C ($R_C$) relative to deuterium ($R_D$). These results indicate regions in which in $R_C>R_D$, requiring that the nuclear modifications be different in all three structure functions, $F_2$, $F_1$ and $F_L$.

nucl-ex↗