http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Scaling of Ion Spectral Peaks in the Hybrid RPA-TNSA Region
K. F. Kakolee,M. Borghesi,M. Zepf,S. Kar,D. Doria,B. Ramakrishna,K. Quinn,G. Sarri,J. Osterholz,M. Cerchez,O. Willi,X. Yuan,P. McKenna 한국물리학회 2016 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.68 No.6
The role of the radiation pressure of an intense laser beam in the formation of proton and carbon spectra from thin foils is discussed. The data presented suggests that, in competition with the Target Normal Sheath Acceleration mechanism, the onset of the Light Sail (LS) region of Radiation Pressure Acceleration can be obtained for suitably thin targets at currently available laser intensities,. The spectral features and their scaling with the laser and target parameters are consistent with the scenario of Light Sail (LS) acceleration.
Generation of a quasi-monoergetic proton beam from laser-irradiated sub-micron droplets (8 pages)
Ter-Avetisyan, S.,Ramakrishna, B.,Prasad, R.,Borghesi, M.,Nickles, P.V.,Steinke, S.,Schnurer, M.,Popov, K.I.,Ramunno, L.,Zmitrenko, N.V. AMERICAN INSTITUTE OF PHYSICS 2012 Physics of plasmas Vol.19 No.7
Ultrashort PW laser pulse interaction with target and ion acceleration
Ter-Avetisyan, S.,Singh, P.K.,Kakolee, K.F.,Ahmed, H.,Jeong, T.W.,Scullion, C.,Hadjisolomou, P.,Borghesi, M.,Bychenkov, V. Yu. Elsevier 2018 Nuclear Instruments & Methods in Physics Research. Vol.909 No.-
<P><B>Abstract</B></P> <P>We present the experimental results on ion acceleration by petawatt femtosecond laser solid interaction and explore strategies to enhance ion energy. The irradiation of micrometer thick (0.2–6.0 μ m ) Al foils with a virtually unexplored intensity regime (8 × 10<SUP>19</SUP> W/cm<SUP>2</SUP> – 1 × 10<SUP>21</SUP> W/cm<SUP>2</SUP>) resulting in ion acceleration along the rear and the front surface target normal direction is investigated. The maximum energy of protons and carbon ions, obtained at optimized laser intensity condition (by varying laser energy or focal spot size), exhibit a rapid intensity scaling as <SUP> I 0 . 8 </SUP> along the rear surface target normal direction and <SUP> I 0 . 6 </SUP> along the front surface target normal direction. It was found that proton energy scales much faster with laser energy rather than the laser focal spot size. Additionally, the ratio of maximum ion energy along the both directions is found to be constant for the broad range of target thickness and laser intensities.</P> <P>A proton flux is strongly dominated in the forward direction at relatively low laser intensities. Increasing the laser intensity results in the gradual increase in the backward proton flux and leads to almost equalization of ion flux in both directions in the entire energy range. These experimental findings may open new perspectives for applications.</P>
Ter-Avetisyan, S.,Andreev, A.,Platonov, K.,Sung, J. H.,Lee, S. K.,Lee, H. W.,Yoo, J. Y.,Singh, P. K.,Ahmed, H.,Scullion, C.,Kakolee, K. F.,Jeong, T. W.,Hadjisolomou, P.,Borghesi, M. The Optical Society 2016 Optics express Vol.24 No.24
<P>A significant level of back reflected laser energy was measured during the interaction of ultra-short, high contrast PW laser pulses with solid targets at 30 degrees incidence. 2D PIC simulations carried out for the experimental conditions show that at the laser-target interface a dynamic regular structure is generated during the interaction, which acts as a grating (quasi-grating) and reflects back a significant amount of incident laser energy. With increasing laser intensity above 1018 W/cm(2) the back reflected fraction increases due to the growth of the surface modulation to larger amplitudes. Above 1020 W/cm(2) this increase results in the partial destruction of the quasi-grating structure and, hence, in the saturation of the back reflection efficiency. The PIC simulation results are in good agreement with the experimental findings, and, additionally, demonstrate that in presence of a small amount of pre-plasma this regular structure will be smeared out and the back reflection reduced. (C) 2016 Optical Society of America</P>