Ion spectrometer composed of time-of-flight and Thomson parabola spectrometers for simultaneous characterization of laser-driven ions

Choi, I. W.*; Kim, C. M.*; Sung, J. H.*; Yu, T. J.*; Lee, S. K.*; Kim, I. J.*; Jin, Y.-Y.*; Jeong, T. M.*; Hafz, N.*; Pae, K. H.*; Noh, Y.-C.*; Ko, D.-K.*; Yogo, Akifumi; Pirozhkov, A. S.; Ogura, Koichi; Orimo, Satoshi; Sagisaka, Akito; Nishiuchi, Mamiko; Daito, Izuru; Oishi, Yuji*; Iwashita, Yoshihisa*; Nakamura, Shu*; Nemoto, Koshichi*; Noda, Akira*; Daido, Hiroyuki; Lee, J.*

A composite ion spectrometer has been developed to measure energy spectra and to analyze the species of ions. It consists of a time-of-flight spectrometer measuring signal corresponding to ion numbers as a function of ion flight time, and a Thomson parabola spectrometer using ion deflections by electric and magnetic fields. The two spectrometers can be operated simultaneously and each one gives its own energy spectrum. This system facilitates comparison between the independently measured data and thereby it enhances their reliability. Real-time and shot-to-shot characterizations for laser-driven protons have been possible with the time-offlight spectrometer, and in addition species of ions generated together with the protons can be analyzed with the Thomson parabola spectrometer. Both spectrometers show good agreement with each other in terms of a maximum proton energy, even for a single laser shot. If we take into account the solid angle and position of measurement, difference in spectral distribution of proton energy may be measured when proton beam regions detected by the two spectrometers are different.