We report here an observation of Delta n = 1 dielectronic recombinatio
n resonances of boron-like argon in the energy region 140-195 eV. With
the cooler's electron beam as a target, a resolution of approximately
0.6 eV FWHM was obtained in the observed energy range. The energies o
f the doubly excited states were estimated with a Hartree-Fock calcula
tion, which indicates that the observed resonances are from Ar13+(1s(2
)2s(2)2p) to Ar12+(1s(2)2s(2)3l3l') and Ar12+(1s(2)2s2p3l3l') transiti
ons.