Search arXiv⌕ Search
Home/Archive/arXiv

arXiv · hep-ex/0512021

Proposal of Direct Search for Strongly Bound States of ppbar, npbar Systems with High Intensity and Collective pbar beam

Haibo Li·Maozhi Yang·Changzheng Yuan
View original source ↗Read source document ↗Export metadata ↓

Abstract

In this letter, we discuss the possibility to look for the direct evidence of the existence of the ppbar and npbar bound states. Measurement of the single γray from the ppbar and npbar systems at rest can directly confirm whether the X(1860) and X(1835) are the resonances which are strongly coupled to ppbar. In addition to the neutral candidate, a charged resonance $X^-$ is also proposed to be searched for in npbar channel. We find that the data from the Crystal Barrel experiment at LEAR/CERN can be used to confirm the X(1835) observed by BES Collaboration. The possibility of measuring the $γ$ spectrum below 100 MeV at the new experiment with cold high intensity $\pbar$ beam at GSI is discussed. These new techniques can be used to probe the structure of the X(1860) and X(1835) in the future.

Explore related subjects

hep-ex

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Haibo Li, Maozhi Yang, Changzheng Yuan. 2006-05-12. Proposal of Direct Search for Strongly Bound States of ppbar, npbar Systems with High Intensity and Collective pbar beam. https://doi.org/10.1142/s0217732306020093

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

KEEP EXPLORING

Related papers

arXiv2026

The mathematical theory of photomultiplier tube calibration

In this technical note we describe the main features of the mathematical theory of photomultiplier tube (PMT) calibration. Attention was paid to explain the various arguments and concepts in a simple and pedagogical manner that everybody understands. The basic operational principles of a PMT are discussed from a theoretical standpoint. The essential steps of its function (photoconversion, focusing, multiplication, etc.) are laid down together with the mathematical schemes necessary to model the charge output of a PMT when illuminated by a faint poissonian light source. In case of important omissions we direct the reader to some of the standard references. The most common numerical methods, used to calculate the charge amplification function $S_R(x)$, are also presented. As an example, we plot $S_R(x)$ utilizing a gamma function model for the single photoelectron (SPE) response and showcase its main characteristics. The basic techniques for gain calibration are also introduced, and we probed their precision using toy Monte Carlo data. Additionally, data from a Hamamatsu R1408 PMT were analyzed. Finally, we show how the presence of soft charge component can affect the results of gain determination. We conclude this report with some general comments regarding \emph{in situ} calibration of large-scale detectors. We hope that this document can serve as a reference for students and young researchers that want to learn more about the theory of PMT calibration.

hep-ex↗
arXiv2026

Strangeness Production at GlueX

The GlueX experiment at Jefferson Lab is well suited for exclusive studies of strangeness production, combining a linearly polarized photon beam at $8.0 < E_γ< 8.8$ GeV with a large-acceptance detector that reconstructs weakly decaying hyperons. We outline a research program built on three aspects: (i) spectroscopy of strange mesons, where many excited $K^*$ states remain unestablished and crypto-exotic strange hybrids must be identified from combined spectrum and decay information, anchored by the $K^*(892)$ as a standard candle; (ii) spin dynamics, where the first precise measurements of the complete spin-density matrix elements in the photoproduced $K^*(892)Λ$ system beyond the Schilling formalism constrain the $t$-channel strange production mechanism; and (iii) hadronization, probed through the newly published $p\bar{p}$, $Λ\barΛ$, and $p\barΛ$ photoproduction cross sections and emerging $Λ\barΛ$ spin-correlation measurements. We place these efforts in the context of the broader GlueX strangeness program and give an outlook toward the high-statistics GlueX-II era.

hep-ex↗
arXiv2026

Feasibility Study of $e^+e^-\to η_cJ/ψ$ Production and Fully-Charmed Tetraquark Searches at STCF

The proposed high-luminosity Super Tau-Charm Facility (STCF) offers a clean experimental environment for threshold studies of exotic hadrons. In this Letter, we evaluate the expected significance for the fully-charmed vector tetraquark candidate $T_{4c}$ in the $e^+e^- \to η_c J/ψ$ channel at the STCF. Using Monte Carlo simulations of an energy scan from $\sqrt{s}=6.71$ to $6.79~\mathrm{GeV}$ with $100~\mathrm{fb}^{-1}$ per point, we adopt a high-efficiency single-tag (ST) reconstruction of $J/ψ$ leptonic decays as the primary strategy, with a double-tag (DT) reconstruction of $η_c \to K^+K^-π^0$ retained as an independent cross-check. Because the signal cross section is governed by the still-uncertain dielectron width $Γ_{ee}$, we consider three benchmark hypotheses, $Γ_{ee}=0.25, 0.5, 1~\mathrm{eV}$. The corresponding expected ST significances are $5.1\,σ$, $10.6\,σ$, and $20.5\,σ$, respectively. These results indicate that the STCF can provide meaningful sensitivity to fully-charmed tetraquark states near threshold.

hep-ex↗