Abstract
Abstract
The coupled structure with ladder radio-frequency quadrupole
(RFQ) and interdigital H-type drift tube linac (IH DTL) has been
proposed to accelerate the proton beam to several MeV with high
acceleration gradient and one RF feed-in system. A ladder RFQ-IH DTL
coupled structure was designed to accelerate a proton beam 2.5 MeV
with a peak current of 15 mA. Detailed dynamics optimization and
error study were performed to achieve high transmission efficiency
and small emittance growth, including ladder RFQ, coupling section
and IH DTL section. The Kombinierte Null Grad Struktur (KONUS)
dynamics scheme with two quadrupole doublets (QDs) was adopted in
the IH-DTL section. Start-to-end beam tracking results showed that
the proton beam can be accelerated to the final energy with a length
of 2.11 m and a transmission efficiency above 98.5%. In addition,
we performed error sensitivity analysis and the combined error study
to evaluate the error tolerance limits of the ladder RFQ-IH DTL
coupled structure.