Witnessing the fragmentation of a filament into prestellar cores in Orion B/NGC 2024

Recent Herschel observations of nearby clouds have shown that filamentary structures are ubiquitous and most prestellar cores form in filaments. Probing the density ($n$) velocity ($V$) structure filaments is crucial for understanding star formation process. To characterize both $n$ $V$ field a fragmenting filament, we mapped NGC2024. 13CO, C18O, H13CO+ trace filament seen $N_{H_2}$ data. The radial profile from data shows $D_{HP}$~0.081 pc, which similar to findings. $D_{HP}$ 13CO C18O broader, while narrower, than Herschel. These results suggest only outer part inner part. $V_{centroid}$ map reveals gradients along axis, as well oscillations with period $\lambda$~0.2 pc major axis. Comparison between distribution tentative $\lambda$/4 shift or C18O. This not simultaneously observed all any single tracer but tentatively either We produced toy model taking into account transverse gradient, longitudinal oscillation mode caused by fragmentation. Examination synthetic component produces an pattern function (VSF) model. VSF pattern, suggesting our partly tracing core-forming motions also found mean $M_{core}$ corresponds effective $M_{BE}$ filament. consistent scenario higher-mass higher line-mass