55648402
Beam Commissioning of KOMAC Linac
The KOMAC (Korea multi-purpose accelerator complex), whose first phase is the proton engineering frontier project, developed a 100-MeV proton linac which consists of a 50 keV injector, a 3-MeV radio frequency quadrupole (RFQ) and a 100-MeV drift tube linac (DTL). The installation of the linac was finished and in commissioning stage. The goal of the beam commissioning in June 2013 is accelerating 100-MeV proton beams with the beam power of 1 kW to the beam dump which is located downstream of the linac. This work summarized the present status and plan of the beam commissioning of the linac.
124789806
INSTALLATION AND OPERATION OF THE BEAMLINES FOR THE 100-MeV PROTON LINAC
Beamlines and 100-MeV proton linac have been developed for 1st phase of KOMAC(Korea Multi-purpose Accelerator Complex) at the Gyeong-ju site. The linac supplies either 20-MeV or 100-MeV proton beams for beam applications. Each proton beam can be transported to 2 beamlines for industrial purpose and 3 beamlines for various researches. At the first phase, 2 beamlines were installed and under test.
113201344
Design of Machine Protection System for the PEFP 100MeV Linac
126282229
STATUS OF 100-MeV PROTON LINAC DEVELOPMENT FOR PEFP
125669672
OPERATION OF THE PEFP 20MEV PROTON LINAC AT KAERI
140083239
BEAM TESTS OF THE PEFP 20 MEV ACCELERATOR *
Proton Engineering Frontier Project (PEFP) 20MeV proton accelerator has been installed and tested at KAERI (Korea Atomic Energy Research Institute) site. After the radiation license was issued, some parts were modified to increase a peak beam current above 1mA. A proton injector composed of an ion source and a LEBT (Low Energy Beam Transport) was modified for better transmission rate through the LEBT. The field profile of the RFQ was measured to check the dipole field effect. In addition, beam loss was measured along the DTL to check and adjust the operating parameters. In this paper, the modifications of the 20MeV accelerator are summarized and the recent test results are presented.
15073869
Non-Supersymmetric Unattractors in Born-Infeld Black Holes
We investigate unattractor behavior in non-extremal black holes in Einstein-Born-Infeld-Dilaton theory of gravity in four-dimensional asymptotically flat spacetime. We obtain solutions which are non-singular near the horizon and dependent on the value of the dilaton field at the infinity, using perturbation method. It is shown that the value of the scalar field at the horizon is determined by its asymptotic value and the charges carried by the black hole. And we also find it is not true in general that the dilaton value at the horizon is a monotonically increasing function of the first coefficient of its series expansion in non-extremal Born-Infeld black holes.
12388929
Non-supersymmetric attractors in BI black holes
Abstract We study attractor mechanism in extremal black holes of Einstein–Born–Infeld theories in four dimensions. We look for solutions which are regular near the horizon and show that they exist and enjoy the attractor behavior. The attractor point is determined by extremization of the effective potential at the horizon. This analysis includes the backreaction and supports the validity of non-supersymmetric attractors in the presence of higher derivative interactions in the gauge field part.
120454450
Einstein-Maxwell-Dilaton Black Branes with Arbitrary Tension and Dilaton Charge
In this note, we show that special choice of the metric ansatz simplifies the equations of motion for black branes. Then we use the trick to construct charged, dilatonic black branes of Einstein–Maxwell–dilaton gravity in D = n + p + 2 dimensions, which are invariant under translation along p directions and have spherical symmetry of Sn. The solutions are characterized by mass density and tension, magnetic charges, dilaton charge and coupling constant.
118397938
BRANE SOLUTIONS WITH TENSION
In this note, we apply a special metric ansatz to simplify the equations of motion for gravitational systems. Then we construct charged brane solutions in D = n+p+2 dimensions which have spherical symmetry of Sn and translational symmetry along p directions. They are characterized by mass density, uniform tension and electric/magnetic charges, and nonsingular only for specific tension. In particular, we find the limits and the coordinate transformations which reduce the charged brane solutions to M2- and M5-branes. We also obtain the regularity condition for an electrically charged two-brane solution which has two tensions.