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Mapping the global heliosphere by detecting energetic neutral atoms (ENAs), IBEX derived the semi‐direct information on the structure of the large‐scale magnetic field surrounding the heliosphere. Multi‐TeV galactic cosmic rays (GCRs) also sense the global structure of the magnetic field within the whole heliosphere as well as the field surrounding the heliosphere, and can provide an additional tool to explore the global structure of these fields. We analyze, in this context, the multi‐TeV GCR intensity observed with the Tibet Air Shower (AS) experiment, which clearly shows a midscale component structure observed as the excess intensity along Gurnett’s HDP (Hydrogen Deflection Plane), as well as the global component structure. We find that the amplitude of the midscale component is only weakly dependent on GCR energy, while its angular extension along the HDP plane monotonously decreases with increasing energy. On the basis of these results, we discuss the possible origin of the midscale anisotropy.

A new cryogenic system was installed on September of the year 2006 at NSRRC. So far, two superconducting magnets and one superconducting cavity for RF are cooled by one 450W liquid Helium system which had already been installed on the year 2002. The new system is planning to supply the liquid helium to five superconducting magnets and being a backup of the first one by transfer valve box. This paper presents the variation of parameters which were precooling temperature (from 87K to 200K), cold turbine outlet temperature (from 10K to 11.5K) and heating power of Dewar to the stability of system performance and liquefaction rate.

A helium cryogenic plant with a maximum cooling power of 450 W at 4.5K was installed at the end of the year 2003. This plant has provide the cooling power for the test of one superconducting cavity and the commission of one superconducting magnet for nine months. In November 2004, we installed one helium transfer system in NSRRC’s storage ring to fulfill the cooling requirement for the operation of one superconducting cavity and two superconducting magnets. This helium transfer system consists of a switch valve box and the nitrogen‐shielding multi‐channel transfer lines. The averaged heat leak to the helium process line (including the straight section, the joint, the elbow, the coupling) at liquid helium temperature is specified to be less than 0.1 W/m at 4.2K; the total heat leak of the switching valve box to helium process lines is less than 16 W at 4.2K. In this paper we present the function, design parameters and test result of the helium transfer system. Commissioning results of both the cavity and the magnets using this helium transfer system will be shown as well.

At NSRRC, an electron accelerator with a beam current of 400 mA at 3 GeV and an emittance of 2 nm‐rad is under planning. Four superconducting cavities are required to keep the electron energy in the storage ring and superconducting insertion magnets are used as the major devices providing the desired photon energy with high brilliance and flux. This paper shows the design features of the helium cryogenic system for superconducting devices. The cryogenic system consists of two cryogenic plants each with 450 W at 4.5 K for the cavities and one cryogenic plant with 600 W at 4.5 K for the magnets. Redundancy is achieved by switching valves and interconnection piping between the three cryogenic plants. Distribution of the liquid helium to the superconducting magnets is planned via two 250 m multichannel lines with up to 24 supplying ports for the candidate positions of superconducting magnets.