Indonesian Journal of Physics 2018-05-04T12:41:02+08:00 Dwi Irwanto Open Journal Systems Neo-R1000: A Fast And Efficient Compact Spectrograph For Emission Line Objects Study At Bosscha Observatory 2018-05-04T12:41:01+08:00 Hakim L Malasan Imanul Jihad Robiatul Muztaba Irham T Andika Evaria Puspitaningrum Akira Arai Hideyo Kawakita T Yamamuro <div class="page" title="Page 1"> <div class="layoutArea"> <div class="column"> <p><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPSMT';">In 2015, the Institute Teknologi Bandung (ITB) signed a Memorandum of Understanding with Sangyou Kyoto University (KSU). One realization of collaboration between ITB and KSU is observational program of Novae using a compact spectrograph NEO-R1000 (Novae and Emission line Objects with Resolution of 1000). This spectrograph is mounted at the Celestron C-11 (</span><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPS'; font-style: italic;">F</span><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPSMT';">/10.0) reflector and supported by a Losmandy G-11 equatorial mounting inside the GAO-ITB sliding roof building, Bosscha observatory, Lembang. The unique configuration of this spectrograph is the employment of mirror collimator and camera lens with focal length ratio of 3:1. This makes it has high speed characteristics. A slit width of 6.5 μm (4.7” @ C-11 reflector ) is combined with a fixed transmission grating of 600 grooves/mm and equipped with a ST-8 XME CCD camera (9 </span><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPSMT';">μ</span><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPSMT';">m per pixel, 1530 </span><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPSMT';">× </span><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPSMT';">1024 pixels), resulting in a resolution of </span><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPS'; font-style: italic;">R</span><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPSMT';">≈ </span><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPSMT';">1000 at a wavelength of 5800 Å with effective spectrum wavelength coverage </span><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPSMT';">Δ</span><span style="font-size: 10.000000pt; font-family: 'SymbolMT';">l </span><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPSMT';">4000-8000 Å. NEO-R1000 spectrograph has additional peripherals such as a Fe-Ne-Ar hollow cathode tube (HTC) which is used as a comparison source. We take flat-field spectrum by using an acrylic board and a halogen lamp. The main primary aim of this spectrograph is to observe the Classical Novae in the southern sky as part of Collaborative Spectroscopic Observations for the Detection of Molecules in Classical Novae. This spectrograph can also be used to observe other emission line objects such as Planetary Nebulae, Comets, P Cygni star type, WR stars and Be stars. In June 2015, this spectrograph was successfully used to observe Nova Sgr 2015 no 2. </span></p> <p><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPSMT';">Further developments of this spectrograph includes constructing a rotator to be attached to the flange of telescope to ensure high flexibility in observation of extended objects. In the future, a fiber optic connecting output pupil with the entrance slit of the spectrograph will be deployed to improve observational effectivity while reducing the load of spectrograph on telescope. </span></p> </div> </div> </div> 2016-07-01T00:00:00+08:00 Copyright (c) Effect of Tool Rotation Speed on Mechanical Properties and Microstructure as the Results of Friction Stir Welding Method on Aluminium 5083-7075 2018-05-04T12:41:02+08:00 Maryati Maryati Bambang Soegijono M Yudi Masduky Tarmizi Tarmizi <div class="page" title="Page 1"> <div class="layoutArea"> <div class="column"> <p><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPSMT';">Friction Stir Welding (FSW) is a new method of welding process which is affordable and provide good quality. Aluminium 5083-7075 has been connected successfully by using friction stir welding (FSW) method into butt joint connection form. Tool rotation speed is one of the important parameters in FSW. The changes of rotation speed will affect the characteristics of mechanical properties and microstructure. The parameters of welding being used are welding speed of 29 mm/minutes by varying the speed rotation of 525 rpm, 680 rpm, 910 rpm, and 1555 rpm. In order to find out the mechanical strength of welds, tensile strength and hardness testing is done while finding out the microstructure will be done by using optical microscope and Scanning Electron Microscope (SEM). The result of the research showed that the highest tensile strength obtained at 910 rpm speed rotation about 244.85 MPa and the greatest hardness values was found on aluminium 5083 around the wheel zone area about 96 HV with rotary speed of 525 rpm. Then, the result of testing the macro and microstructure on all samples indicated defect which is seen as incomplete fusion and penetration causing the formation of onion rings. In other words, it is which showed that the result of stirring and tacking in the welding area is less than perfect. </span></p> </div> </div> </div> 2016-07-01T00:00:00+08:00 Copyright (c) Design and Analysis Effect of Gantry Angle Photon Beam 4 MV on Dose Distributions using Monte Carlo Method EGSnrc Code System 2018-05-04T12:41:02+08:00 Uum Yuliani Ridwan Ramdani Freddy Haryanto Yudha Satya Perkasa Mada Sanjaya <div class="page" title="Page 1"> <div class="layoutArea"> <div class="column"> <p><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPSMT';">Varian linac modeling has been carried out to obtain Percentage Depth Dose (PDD) and profiles using variations gantry angle 0<sup>o</sup>, 15<sup>o</sup>, 30<sup>o</sup> , 45<sup>o</sup> in the vertical axis of the surface, field size 10x10 cm</span><span style="font-size: 6.000000pt; font-family: 'TimesNewRomanPSMT'; vertical-align: 5.000000pt;">2</span><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPSMT';">, photon beam 4 MV and Monte Carlo simulations. Percentage Depth Dose and profile illustrates dose distributions in a phantom water measuring 40x40x40 cm</span><span style="font-size: 6.000000pt; font-family: 'TimesNewRomanPSMT'; vertical-align: 5.000000pt;">3</span><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPSMT';">, changes gantry is one of the factors that determine the distribution of the dose to the patient research shows changes in Dmax in the Percentage Depth Dose is affected by changes in the angle gantry resulted in the addition of the area build up so it can be used for therapy in the region and produce skin sparing effects that can be used to protect the skin from exposure to radiation. The graph result is profiles obtained show lack simetrisan in areas positive quadrant has a distribution of fewer doses than the quadrant of negative as well as the slope of the surface so that it can be used for some cases treatments that require a depth and a certain slope, dose calculations are more accurate and can minimize side effects. </span></p> </div> </div> </div> 2016-07-01T00:00:00+08:00 Copyright (c) 2-Dimensional Pressure Distribution in Saturated Petroleum Reservoir using Finite Difference 2018-05-04T12:41:02+08:00 Adam Sukma Putra Wahyu Srigutomo <div class="page" title="Page 1"> <div class="layoutArea"> <div class="column"> <p><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPSMT';">The aim of this project is to solve the Darcy’s Equation using the finite difference (FD) method. We test the governing equation by investigating a saturated petroleum reservoir in two-dimensional (2-D) system to describe the distribution of the pressure within the reservoir. We assume that the velocity of the fluid (oil) is incompressible and relatively slow as a consequence that the system is saturated. The model used is a flow in steady state 2-D porous media. We apply the modified form of FN method with Gauss-Seidel to improve the precision of the simulation. </span></p> </div> </div> </div> 2016-07-01T00:00:00+08:00 Copyright (c) 2016 Indonesian Journal of Physics Skyrme-Extended-Thomas-Fermi Approach Method In Investigation of Nuclear Ground State Properties of 208Pb 2018-05-04T12:41:02+08:00 Yacobus Yulianto Zaki Su'ud <div class="page" title="Page 1"> <div class="layoutArea"> <div class="column"> <p><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPSMT';">In this research, it is performed the nuclear ground state properties investigation of </span><span style="font-size: 7.000000pt; font-family: 'TimesNewRomanPSMT'; vertical-align: 5.000000pt;">208</span><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPSMT';">Pb by using the SETF method with SLy4 set parameters. The energy optimization calculation is performed using SETFA code. The SETFA results are in good agreement with the related experiment results, and also with the results of the HFBRAD and HFODD- HFBTHO codes. It is can be indicated that </span><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPS'; font-style: italic;">Skyrme-Extended-Thomas-Fermi </span><span style="font-size: 10.000000pt; font-family: 'TimesNewRomanPSMT';">method can be used to explain the nuclear ground state properties, especially even-stable nucleus. </span></p> </div> </div> </div> 2016-07-01T00:00:00+08:00 Copyright (c)