Seminars
Our seminars take place in the lecture room of the building at
Praha–Sporilov.
Next seminar:
12.08.2013 13:00
Michaela Brchnelova
Gymnasium Hubeneho 23, Bratislava
X-ray dynamics measurements of the Tycho’s supernova remnant G120.1+01.4
Abstract
Michaela Brchnelova
X-ray dynamics measurements of the Tycho’s supernova remnant G120.1+01.4
Intel International Science and Engineering Fair 2013, international pre-college science competition.
In the following work we present X-ray dynamics measurements of the Tycho’s supernova remnant G120.1+01.4. We compare observations and spectra from 2005 and 2009 archived in XMM-Newton Science Archive in order to determine differences caused by collision with surrounding interstellar medium (ISM) as well as by remnant’s own expansion. We have calculated the azimuthal expansion of remnant’s edges to vary from 0.194 arcsec/yr to 0.438 arcsec/yr, while the highest values are found to have the azimuth of about 60° in the south-east and the lowest expansion overall is estimated on the north. Comparison of fluxes has shown that the highest estimated energy gain of 3.1 times was measured in reverse shock region around the azimuth of 300° in the energy range from 6.1 keV to 8 keV, whereas the highest energy loss was found to be in the same energy range in forward shock region with the azimuth of approximately 70° reaching 2.4 times lower energy compared with the values from 2005. We have also defined the most abundant heavy elements within energy scale from 200 eV to 8 keV, which are identified through spectral lines to be Fe XVIII (0.849 keV), Mg XI and XII (1.34 keV, 1.46 keV), Si XIII (1.83 keV), S XV (2.41 keV, 2.86 keV) and Ca XIX (3.84 keV).
Previous seminar:
02.07.2013 15:00
Dong Lai
Department of Astronomy, Cornell University, Ithaca
Merging Compact Binaries
Abstract
Dong Lai
Merging Compact Binaries
The merger of binary systems containing neutron stars, black holes or white dwarfs can lead to various extreme phenomena that are observable throughout the universe. I will discuss recent works on merging neutron star/black hole binaries and white dwarf binaries, focusing on dynamical processes in the pre-merger phase, gravitational waves and potential constraint on nuclear matter.
Time permitting, I will also give a brief review on the physics of matter and radiation in strong magnetic fields and how it affects the observational manifestations of various isolated neutron stars.
If you would like to give a seminar in our group, please contact Vladimir Karas or Jaroslav Hamersky.
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