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A significant deceleration effect on a stored coasting ion beam by a continuous-wave laser light was observed in the Schottky-noise spectrum during the laser experiments with lithium-like oxygen ion beams stored at a relativistic energy of 275.7 MeV/u at the heavy-ion storage ring CSRe in Lanzhou, China. The observed deceleration range of the laser (Δp/p≈5.7×10−6) is much broader than the expected capture range (Δp/p≈3.6×10−8), as calculated from the natural linewidth of the O5+ ion’s electronic transition (2S1/2 −2 P1/2). In order to explain this huge deviation, a phase space tracking code has been developed to investigate the interaction between the stored coasting ion beam and the laser light. Simulations reveal that the deceleration range of the typically narrow CW laser force is highly enlarged by taking into account the transverse betatron oscillation of the ions with larger emittance and the angular misalignment of the laser light direction. The experimental observation is well described by the systematic simulations. The present work is crucial for forthcoming laser cooling and precision laser spectroscopy experiments and simulations on heavy highly charged ions at the CSRe and the future facility HIAF.

Purpose/Objective(s) This study evaluated the survival benefit of asparaginase (ASP)-based versus non-ASP-based regimens in a real-world cohort of patients with early-stage extranodal nasal-type NK/T-cell lymphoma (ENKTCL). Materials/Methods In the modern era, we identified 376 patients who received combined radiotherapy with either ASP-based (asparaginase, platinum and gemcitabine, n = 286) or non-ASP-based (platinum and gemcitabine, n = 90) regimens. The patients were stratified into low-, intermediate- and high-risk groups using the early stage-adjusted nomogram-revised risk index (ES-NRI). Overall survival (OS) and distant metastasis (DM)-free survival (DMFS) between the chemotherapy regimens were compared using inverse probability of treatment weighting (IPTW) and multivariable analyses. Results ASP-based (versus non-ASP-based) regimens significantly improved 5-year OS (84.5% vs. 73.2%, P = 0.021) and DMFS (84.4% vs. 74.5%, P = 0.014) for intermediate- and high-risk patients, but not for low-risk patients. Moreover, ASP-based regimens decreased DM, with 5-year cumulative DM rate of 14.9% for ASP-based regimens compared with 25.1% (P = 0.014) for non-ASP-based regimens. The survival benefit of ASP-based regimens remained consistent after adjusting the confounding variables by IPTW and multivariate analyses. Additional sensitivity analyses confirmed these results. Conclusion These findings provide an evidence supporting ASP-based regimens as a first-line combined-modality treatment for intermediate- and high-risk early-stage ENKTCL.