Measurement of the Reaction {sup 2}H(e,e{sup '}) at 180 deg. Close to the Deuteron Breakup Threshold

Inclusive inelastic electron scattering off the deuteron under 180 deg. has been studied at the S-DALINAC close to the breakup threshold at momentum transfers q=0.27 fm{sup -1} and 0.74 fm{sup -1} with good energy resolution sufficient to map in detail the spin flip M1 response, which governs the starting reaction pn{yields}d{gamma} of big-bang nucleosynthesis over most of the relevant temperature region. Results from potential model calculations and (for q=0.27 fm{sup -1}) from pionless nuclear effective field theory are in excellent agreement with the data.