• Title/Summary/Keyword: particle physics

Search Result 471, Processing Time 0.036 seconds

Computational Science-based Research on Dark Matter at KISTI

  • Cho, Kihyeon
    • Journal of Astronomy and Space Sciences
    • /
    • v.34 no.2
    • /
    • pp.153-159
    • /
    • 2017
  • The Standard Model of particle physics was established after discovery of the Higgs boson. However, little is known about dark matter, which has mass and constitutes approximately five times the number of standard model particles in space. The cross-section of dark matter is much smaller than that of the existing Standard Model, and the range of the predicted mass is wide, from a few eV to several PeV. Therefore, massive amounts of astronomical, accelerator, and simulation data are required to study dark matter, and efficient processing of these data is vital. Computational science, which can combine experiments, theory, and simulation, is thus necessary for dark matter research. A computational science and deep learning-based dark matter research platform is suggested for enhanced coverage and sharing of data. Such an approach can efficiently add to our existing knowledge on the mystery of dark matter.

Polarized Light Scattering Spectroscopy for Particle Size Measurement on Surface (편광산란분광법을 이용한 표면의 입자 크기 측정)

  • Cho, Hyoung-Jun;Choi, Chi-Kyu;Kim, Doo-Chol;Yu, Young-Hun
    • Korean Journal of Optics and Photonics
    • /
    • v.16 no.6
    • /
    • pp.560-564
    • /
    • 2005
  • We used the polarized light scattering spectroscopy(PLSS) to get selectively the particle size information on a surface in optically diffuse material, and we analyzed the experimental results by Mie scattering theory. We found that the PLSS was the proper method fer getting the surface information in optically diffuse material. This method is able to be used in biotechlology area for diagnostics.

Particle Acceleration by High Power (> TW) Femtosecond Lasers in Plasmas (고출력 펨토초 레이저와 플라즈마를 이용한 입자가속)

  • Suk, H.;Hafz, N.;Kim, C.B.;Kim, G.H.;Kim, J.U.;V. Kulagin;Lee, H.J.;Kim, J.C.;Ko, I.S.;Hahn, S.J.;Pae, G.H.
    • Proceedings of the Optical Society of Korea Conference
    • /
    • 2003.07a
    • /
    • pp.62-62
    • /
    • 2003
  • Charged particles can be accelerated to relativistic high energies by high power (> terawatt) laser beams. We have a research project on laser and plasma-based advanced accelerators in Center for Advanced Accelerators at Korea Electrotechnology Research Institute (KERI), in which the 2 TW (1.4 J/700 fs) Ti:sapphire/Nd:glass hybrid laser system and a He plasma will be used for particle acceleration experiments. In this presentation, we introduce the ongoing research activities and the planned experiments at KERI.

  • PDF

Basics of particle therapy I: physics

  • Park, Seo-Hyun;Kang, Jin-Oh
    • Radiation Oncology Journal
    • /
    • v.29 no.3
    • /
    • pp.135-146
    • /
    • 2011
  • With the advance of modern radiation therapy technique, radiation dose conformation and dose distribution have improved dramatically. However, the progress does not completely fulfi ll the goal of cancer treatment such as improved local control or survival. The discordances with the clinical results are from the biophysical nature of photon, which is the main source of radiation therapy in current field, with the lower linear energy transfer to the target. As part of a natural progression, there recently has been a resurgence of interest in particle therapy, specifically using heavy charged particles, because these kinds of radiations serve theoretical advantages in both biological and physical aspects. The Korean government is to set up a heavy charged particle facility in Korea Institute of Radiological & Medical Sciences. This review introduces some of the elementary physics of the various particles for the sake of Korean radiation oncologists' interest.

An Analysis on Treatment Schedule of Carbon Ion Therapy to Early Stage Lung Cancer

  • Sakata, Suoh;Miyamoto, Tadaaki;Tujii, Hirohiko
    • Proceedings of the Korean Society of Medical Physics Conference
    • /
    • 2002.09a
    • /
    • pp.174-176
    • /
    • 2002
  • A total of 134 patients with stage 1 of non-small cell lung cancer treated by carbon ion beam of HIMAC NIRS were investigated for control rate and delivered dose. The delivered dose of every patient was converted to biological effective dose (BED) of LQ model using fraction number, dose per fraction and alpha beta ratio which shows the maximum correlation between BED and tumor control. The BED of every patient was classified to establish a BED response curve for control. Assuming fraction numbers, dose response curves were introduced from BED response curve. The total doses to realize several control rates were obtained for the treatment of small fraction number.

  • PDF

The Reconstruction of Atmospheric Particle Size Distributions Using Optical Sensing Data and Some Regularization Methods l : Direct Methods (광측정 데이터와 최적화 방법들을 이용한 대기입자 크기분포 복원)

  • Kim, Seok-Seong;Yeon, Kyu-Hwang;Kim, Duck-Hyun
    • Proceedings of the Korea Air Pollution Research Association Conference
    • /
    • 2003.11a
    • /
    • pp.213-214
    • /
    • 2003
  • Atmospheric particles have a great deal of influences on the climate and the air quality, which change the living and industrial environments of a specific area. Especially, the suspended dusts and aerosols can often have a harmful influences on workers' health, equipments at working places. For this reasons, the measurement of atmospheric particle size distributions is of considerable current interest. (omitted)

  • PDF

A Low-Density Graphite-Polymer Composite as a Bipolar Plate for Proton Exchange Membrane Fuel Cells

  • Dhakate, S.R.;Sharma, S.;Mathur, R.B.
    • Carbon letters
    • /
    • v.14 no.1
    • /
    • pp.40-44
    • /
    • 2013
  • The bipolar plate is the most important and most costly component of proton exchange membrane fuel cells. The development of a suitable low density bipolar plate is scientifically and technically challenging due to the need to maintain high electrical conductivity and mechanical properties. Here, bipolar plates were developed from different particle sizes of natural and expanded graphite with phenolic resin as a polymeric matrix. It was observed that the particle size of the reinforcement significantly influences the mechanical and electrical properties of a composite bipolar plate. The composite bipolar plate based on expanded graphite gives the desired mechanical and electrical properties as per the US Department of Energy target, with a bulk density of 1.55 $g.cm^{-3}$ as compared to that of ~1.87 $g.cm^{-3}$ for a composite plate based on natural graphite (NG). Although the bulk density of the expanded-graphite-based composite plate is ~20% less than that of the NG-based plate, the I-V performance of the expanded graphite plate is superior to that of the NG plate as a consequence of the higher conductivity. The expanded graphite plate can thus be used as an electromagnetic interference shielding material.