J-PARC E07: Systematic Study of Double Strangeness System with Hybrid Emulsion Method

Abstract

J-PARC E07 is the most ambitious and complex emulsion experiment to date investigating double hypernuclei with Hybrid emulsion method. The physics run at the K1.8 beam line in the J-PARC hadron experimental facility have been completed in 2017. The emulsion sheets are presently being analyzed with dedicated optical microscopes. Current statistics are estimated to be more 3 times than that of previous experiments. Quantitative data on the ΛΛ and ΞN interaction are being accumulated successfully via analysis of double Λ and Ξ hypernuclei. Multiple Ξ hypernucleus candidates suggests several features about Ξ hypernucleus that the identification efficiency of 15 Ξ C is significantly higher than other mode, many daughters of 15 Ξ C are identified as He or Be, and multiple bound states of Ξ − exist in the 14 N nucleus. An analysis of X-ray spectroscopy of Ξ − hyperatoms are onging.

Cancelled: Line Segment Detection Based on False Peak Suppression and Local Hough Transform and Application to Nuclear Emulsion

“…In the J-PARC E07 experiment [18], the cosmic rays and Compton electrons generated by gamma rays from radioactive substances in the experimental environment are recorded as trajectories in the nuclear emulsion layer, which leads to the deterioration of the visual observation quality of alpha delay phenomenon related to the detection of double Λ hypernuclei in nuclear emulsion. It is necessary to expose the nuclear emulsion to the light beam and to develop and scan it as soon as possible after the photographic plate is made.…”

“…It is mainly used to eliminate the influence of uneven development, and highlight the linear texture information in the image, which is conducive to the detection and extraction of straight line segments in the image. The parameters involved in the threestep image preprocessing process are adjusted adaptively according to the data set of nuclear emulsion tomographic images obtained in the J-PARC E07 experiment [18]. For high quality natural images, the edge features are clearly visible and do not require such a preprocessing process.…”