한가람 교수

Americanae nace como un proyecto conjunto que surge dentro de la Red Europea de Información y Documentación sobre América Latina (REDIAL), y que ha afrontado la Biblioteca de la Agencia Española de Cooperación Internacional para el Desarrollo (AECID). Esta nueva biblioteca virtual hace más accesibles los libros digitales de tema americanista a los investigadores y usuarios interesados de cualquier parte del mundo.

The Higgs boson was postulated nearly five decades ago within the framework of the standard model of particle physics and has been the subject of numerous searches at accelerators around the world. Its discovery would verify the existence of a complex scalar field thought to give mass to three of the carriers of the electroweak force-the W(+), W(-), and Z(0) bosons-as well as to the fundamental quarks and leptons. The CMS Collaboration has observed, with a statistical significance of five standa

Abstract High magnetic fields are desirable for discovering new particles in particle accelerators. Dipole magnets using superconductors have played a key role in creating the required field intensity and uniformity. In contrast, high temperature superconductor (HTS) dipole magnets have recently been spotlit because of their ability to generate higher magnetic fields compared to their low temperature superconductor counterpart. Similar needs have emerged in other fields using magnets, and no-ins

The Korea Heavy Ion Medical Accelerator project (KHIMA) has been proposed as an ion-beam synchrotron facility for cancer therapy. The facility will be installed at Gijang, Busan with completion in 2017. The proposed maximum energy of the ions is 430 MeV/u (for carbon) to cover various tumor depths up to 30 cm. For the synchrotron design, we optimized the lattice configuration to fit the therapy. We discuss here the status of the synchrotron’s design.

This work presents a modified lumped-circuit model for a saddle -shaped no-insulation (NI) high temperature superconductor (HTS) coil in overcurrent, which is defined by the situation that azimuthal current is close to or greater than the critical current. We suggested the variation of the coil's circuit parameters, such as inductance, ‘index’ resistance, and characteristic resistance. We modified the base assumptions of the conventional lumped-circuit model and experimented to validate the sugg

A pepper-pot diagnostic device was developed to accurately and robustly retrieve particle distribution in horizontal and vertical phase spaces by single-shot emittance measurements. Two masks that differ in both composition and manufacturing method were fabricated: one made of phosphor bronze by an optical lithography process, and another made of stainless steel (SUS) by laser cutting. Scanning electron microscope measurements of the two masks revealed that the former is superior in terms of reg

In order to produce a 430 MeV/u carbon ion (12 C 6+) beam for medical therapy, the Korea Institute of Radiological & Medical Sciences (KIRAMS) has carried out the development of a superconducting isochronous cyclotron, the KIRAMS-430. At the extraction of the cyclotron, an Energy Selection System (ESS) is located to modulate the fixed beam energy and to drive the ion beam through High Energy Beam Transport (HEBT) into the treatment room. The beam emittance at the ion beamline is to be measured t

There are increasing interests in high temperature superconducting(HTS) undulator with a gradual increase of engineering current density of REBCO conductor. Additionally, no-insulation(NI) winding technique may maximize the undulator field of HTS undulators mainly benefited from its high engineering current density. In this study, we present several design options of an NI HTS undulator to investigate its anticipated performance in terms of magnetic field strength. Specifically, maximum magnetic

This work presents a distributed-circuitmodel for analyzing experimental results of fast-ramping behaviors of a saddle-shaped REBCO dipole magnet wound with a bundled conductor. Terminal voltage and center magnetic field were measured during the test performed at 77 K temperature. Our distributed-circuit model accurately reproduced the observed electromagnetic behaviors, demonstrating its validity for the fast-ramping operation of an HTS magnet. We also analyzed the current discrepancy between b

KHIMA, a research project to construct a carbon radio-therapy facility in Korea, has been developing a superconducting cyclotron named KIRAMS-430 as a carbon(12 C 6+) particle accelerator. Due to the fixed beam energy of the cyclotron, an energy selection system (ESS) is required for treatment of tumors located at various depths in the human body. In the present paper, two design stages of the ESS are discussed. First, the beam tracks behind the degrader block and the statistical twiss parameter

An active plasma lens (APL) focuses the beam in both the horizontal and vertical planes simultaneously using a magnetic field generated by a discharge current through the plasma. A beam size of $5--10\text{ }\text{ }\ensuremath{\mu}\mathrm{m}$ can be achieved within a short distance using a focusing gradient on the order of $100\text{ }\text{ }\mathrm{T}/\mathrm{m}$. The APL is therefore an attractive element for plasma wakefield acceleration, because an ultrasmall size of the witness electron b