Search arXiv⌕ Search
Home/Archive/arXiv

arXiv · hep-ex/0112008

Crystal experiments on efficient beam extraction

A. G. Afonin·V. M. Biryukov·V. T. Baranov·V. N. Chepegin·Y. Chesnokov·V. Kotov·V. Terekhov·E. Troyanov·V. Guidi·G. Martinelli·M. Stefancich·D. Vincenzi·Yu. Ivanov·D. Trbojevic·W. Scandale·M. Breese
View original source ↗Read source document ↗Export metadata ↓

Abstract

Silicon crystal was channeling and extracting 70-GeV protons from the U-70 accelerator with efficiency of 85.3+-2.8% as measured for a beam of 10^12 protons directed towards crystals of 2 mm length in spills of 1-2 s duration. The experimental data follow very well the prediction of Monte Carlo simulations. This success is important to devise a more efficient use of the U-70 accelerator in Protvino and provides a crucial support for implementation of crystal-assisted collimation of gold ion beam in RHIC and slow extraction from AGS onto E952, now in preparation at Brookhaven Nat'l Lab. Future applications, spanning in the energy from sub-GeV (medical) to order of 1 GeV (scraping in the SNS, extraction from COSY) to order of 1 TeV and beyond (scraping in the Tevatron, LHC, VLHC), can benefit from these studies.

Explore related subjects

hep-ex

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

A. G. Afonin, V. M. Biryukov, V. T. Baranov, V. N. Chepegin, Y. Chesnokov, V. Kotov, V. Terekhov, E. Troyanov, V. Guidi, G. Martinelli, M. Stefancich, D. Vincenzi, Yu. Ivanov, D. Trbojevic, W. Scandale, M. Breese. 2001-12-06. Crystal experiments on efficient beam extraction. https://arxiv.org/abs/hep-ex/0112008

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

KEEP EXPLORING

Related papers

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↗
arXiv2026

From Hits to Tracks: A BERT-based Tracking Model for Track Reconstruction in Drift Chambers

Track reconstruction in drift chambers is essential for momentum measurement and particle identification at electron-positron colliders. While Transformer architectures have transformed many sequence-processing domains, their application to tracking in high energy physics is still being explored. We present a model that combines a BERT encoder with a Transformer decoder to perform hit-to-track association through autoregressive sorting. The model is evaluated on the DCTracks open dataset that provides realistic drift chamber simulations with varying particle types, momenta, track multiplicities, and noise conditions. Across single-track, two-track, and multi-track samples, the model achieves high hit and track efficiencies while keeping the rates of clones and fakes very low. It also works well in the reconstruction of displaced vertices. These results show BERT-based sequence-to-sequence models as a promising approach for track reconstruction in low-background, precision-oriented experiments.

hep-ex↗
arXiv2026

Lowest-radiation environments in the Solar System: New opportunities for underground rare-event searches

We study neutrino, muon, and gamma-ray fluxes in extraterrestrial environments in our Solar System via semi-analytical estimates and Monte Carlo simulations. In sites with negligible atmosphere, we find a strong reduction in the cosmic-ray-induced neutrino and muon fluxes relative to their intensities on Earth. Neutrinos with energies between 50~MeV and 100~TeV show particularly strong suppression, by as much as 10$^3$, even at shallow depths. The solar neutrino suppression increases as the square of the site's distance from the Sun. Natural radiation due to nuclear decay is also expected to be lower in many of these locations and may be reduced to effectively negligible levels in liquid water environments. The sites satisfying these characteristics represent an opportunity for greatly extending the physics reach of underground searches in fundamental physics, such as searches for WIMP Dark Matter, neutrinoless double-beta decay, the diffuse supernova neutrinos, and neutrinos from nearby supernova. As a potential near-term target, we propose a measurement of muon and gamma-ray fluxes in an accessible underground lunar site such as the Mare Tranquillitatis Pit to perform a first measurement of the prompt component in cosmic-ray-induced particle production, and to constrain lunar evolution models. Although the focus of this work is on fundamental physics, the finding of this work -- that the existence of an atmosphere in a planet enhances cosmic-ray-induced radiation in its underground -- could be relevant for a broader range of sciences, such as radiobiology deep underground and searches for extraterrestrial life.

hep-ex↗