- Takeuchi, S;
- Matsushita, M;
- Aoi, N;
- Doornenbal, P;
- Li, K;
- Motobayashi, T;
- Scheit, H;
- Steppenbeck, D;
- Wang, H;
- Baba, H;
- Bazin, D;
- Càceres, L;
- Crawford, H;
- Fallon, P;
- Gernhäuser, R;
- Gibelin, J;
- Go, S;
- Grévy, S;
- Hinke, C;
- Hoffman, CR;
- Hughes, R;
- Ideguchi, E;
- Jenkins, D;
- Kobayashi, N;
- Kondo, Y;
- Krücken, R;
- Le Bleis, T;
- Lee, J;
- Lee, G;
- Matta, A;
- Michimasa, S;
- Nakamura, T;
- Ota, S;
- Petri, M;
- Sako, T;
- Sakurai, H;
- Shimoura, S;
- Steiger, K;
- Takahashi, K;
- Takechi, M;
- Togano, Y;
- Winkler, R;
- Yoneda, K
Excited states in (38,40,42) Si nuclei have been studied via in-beam γ-ray spectroscopy with multinucleon removal reactions. Intense radioactive beams of ^{40}S and (44)S provided at the new facility of the RIKEN Radioactive Isotope Beam Factory enabled γ-γ coincidence measurements. A prominent γ line observed with an energy of 742(8) keV in (42) Si confirms the 2(+) state reported in an earlier study. Among the γ lines observed in coincidence with the 2^{+} → 0+ transition, the most probable candidate for the transition from the yrast 4(+) state was identified, leading to a 4(1)+) energy of 2173(14) keV. The energy ratio of 2.93(5) between the 2(1)+ and 4(1)(+) states indicates well-developed deformation in (42) Si at N = 28 and Z = 14. Also for 38,40)Si energy ratios with values of 2.09(5) and 2.56(5) were obtained. Together with the ratio for (42)Si, the results show a rapid deformation development of Si isotopes from N = 24 to N = 28.