Study of e⁺e⁻ → D⁺D⁻π⁺π⁻ at center-of-mass energies from 4.36 to 4.60 GeV

We report a study of the e⁺e⁻→D⁺D⁻π⁺π⁻ process using e⁺e⁻ collision data samples with an integrated luminosity of 2.5fb⁻¹ at center-of-mass energies from 4.36 to 4.60 GeV, collected with the BESIII detector at the BEPCII storage ring. The D₁(2420)⁺ is observed in the D⁺π⁺π⁻ mass spectrum. The mass and width of the D₁(2420)⁺ are measured to be (2427.2±1.0_stat.±1.2_syst.) MeV/c² and (23.2±2.3_stat.±2.3_syst.) MeV, respectively. In addition, the Born cross sections of the e⁺e⁻→D₁(2420)⁺D⁻+c.c.→D⁺D⁻π⁺π⁻ and e⁺e⁻→ψ(3770)π⁺π⁻→D⁺D⁻π⁺π⁻ processes are measured as a function of the center-of-mass energy.