Nikolay Chechenin, Dr. Sci, professor, is the head of Division of Atom and Nuclear Physics and Laboratory of Nanostructures and Radiation effects at Scobeltsyn Institute of Nuclear Physics of Lomonosov Moscow State University. He runs several projects, including effects of space radiation on on-board electronics.\r\n\r\nMuhammad Sajid, PhD, CIIT Islamabad Pakistan specializes in space radiation effects in on-board electronics devices.
This report addresses the Multiple Cell Upsets in SRAM based on 65nm bulk CMOS technology node. Aggressive downscaling trends in CMOS technology has resulted in decrease of device feature size, power supply voltage and placement of MOS transistors in close proximity to substantially reduce the chip area. If 65nm SRAM bit-cell is struck by high LET particle in close proximity outside bit-cell area, it was found that stored information can be reversed due to charge sharing between the closely place MOS transistors in deep submicron technologies. Therefore, multiple memory cells can be affected by energetic single particle strike. We report Multiple Cell Upsets (MCUs) сross-section (Figure 1) and contribution of multiplicity of MCU events in Single Event Rate (SER) (Figure 2) calculated with MUSCA SEP3 toolkit with typical aluminum spot shielding of 2.54 mm physical mechanism simulation. In order to characterize the radiation hardness of scaled CMOS devices, EDA simulation tools such as MUSCA SEP3 was utilized for MCU rate prediction whereas space radiation environment was estimated with the help of OMERE-TRAD software. The contribution of different sources of space radiation into total SER is shown in Figure 3.
Zeinab is a M.Sc. research student at Astronomy, space sciences and Meteorology department, Cairo University and a demonstrator at the same department. She had successfully completed the Pre-Master courses of mathematical Astronomy at Astronomy, Space sciences and Meteorology department, Faculty of Science, Cairo University.
We have studied the amount of energy lost via gravitational waves emission in the presupernova binary neutron star system (SN 1987A) in a time scale of one hour before the explosion event. We based our work on the Imshennik and Popov (1994) paper then we modified it by\r\n\r\nconsidering the mass variation using the famous Jeans-law and considering\r\n\r\ndiffrent values for the constant (from1.4 to 4.4).\r\n\r\n\r\n\r\nUsing our studied systems’s data and with the aid of Mathematica programme, we get a relation between and the eccentricity which represents the G.W emission stage.\r\n\r\nWe concluded from our curve that the sharp and maximum energy losses via gravitational waves happened at the high eccentricity values i.e. near the periastron position. Also the emission of G.W causes the orbit of the binary system to shrink until it became near circular orbit of e~0.\r\n\r\n\r\nWe have extended our study by considering the variation of one companion mass of the binary according to Jeans -law, the family of curves drawn for different n values indicates that:\r\n\r\nFor 1.4 <1.47 a linear relation shows that decreases with time τ.\r\n\r\nFor 1.47 the curves tend to have curvature with a peak point which happens earlier as the value increases.\r\n