Astrophysical jets play crucial roles in star formation and transporting angular momentum away from accretion discs, however, their collimation mechanism is still a subject of much debate due to the limitations of astronomical observational techniques and facilities. Here, a strong quasi-static toroidal magnetic field is generated through the interaction between lasers and a four-post nickel target, and our all-optical laboratory experiments reveal that a wide-angle plasma plume can be collimated in the presence of toroidal magnetic fields. Besides the confinement effects, the experiments show the jet can also be accelerated by the enhanced thermal pressure due to the toroidal magnetic fields. These findings are verified by radiation magneto-hydrodynamic simulations. The experimental results suggest the astrophysical narrow plasma flow can be produced by the confinement of wide-angle winds through toroidal fields

jet,Laboratory astrophysics,magnetic field