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The X-Ray Spectroscopy of SNR. a ds9 activity. SNR G292.0+1.8. Tycho’s SNR. Beaming home the cosmos. "To make an apple pie from scratch, you must first invent the universe." ~Carl Sagan. From.
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The X-Ray Spectroscopy of SNR a ds9 activity SNR G292.0+1.8 Tycho’s SNR
"To make an apple pie from scratch,you must first invent the universe." ~Carl Sagan
From “The elements have their ultimate origins in cosmic events. Further, different elements come from a variety of different events. So the elements that make up life itself reflect a variety of events that take place in the Universe. The hydrogen found in water and hydrocarbons was formed in the moments after the Big Bang. Carbon, the basis for all terrestrial life, was formed in small stars. Elements of lower abundance in living organisms but essential to our biology, such as calcium and iron, were formed in large stars. Heavier elements important to our environment, such as gold, were formed in the explosive power ofsupernovae. And light elements used in our technology were formed via cosmic rays. The solar nebula, from which our solar system was formed, was seeded with these elements, and they were present at the Earth's formation. Our very existence is connected to these elements, and to their cosmic origin.”
The Periodic Table of the Elements (coded according to the dominant processes which produce the elements) What elements are in formed in supernova remnants? Can the types of supernova event be determined from their spectra?
Determining the type of supernova from a supernova remnant using ds9 analysis tools. Tycho’s SNR Type 1a supernova In the thermonuclear explosion of a white dwarf, the core is completely destroyed. Note the lack of a central point source in Tycho’s SNR. Analyze Tycho’s Supernova Remnant following the instructions at http://www.geocities.com/donnas_stars/chandra_activities/xrayspectroscopyofsnrds9.doc
Sherpa Spectral Fit PROCEDURE
What is Bremsstrahlung radiation? A supernova remnant can have a temperature of millions of degrees Kelvin. Bremsstrahlung radiation occurs in such a hot gas where many electrons are stripped from their nuclei, leaving a population of electrons and positive ions. When an electron passes close to a positive ion, the strong electric forces cause its trajectory to change. The acceleration of the electron in this way causes it to radiate electromagnetic energy - this radiation is called bremsstrahlung and produces a continuous X-ray spectrum. In addition, emission lines canappearsuperimposed on this spectrum, corresponding to the ejection of K and L shell electrons knocked out of atoms by collisions with high-energy electrons. Higher energy electrons then fall into the vacated energy state in the outer shell, and so on, emitting X-ray photons. The energies of these emissions lines can be matched to energies in the CHIANTI Atomic Database to identify the elements in plasmas such as supernova remnants.
Tycho’s SNR Type 1a supernova Zoom in on each peak (left click and drag a box) to determine its energy in keV.
Si 1.8 keV Fe 0.8 keV Mg 1.3 keV S 2.4 keV Ar 3.1 keV Ca 3.9 keV Fe 6.4 keV Tycho’s SNR Type 1a supernova
SNR G292.0+1.8 Type II A Type II supernova occurs when a massive star has used up its nuclear fuel and its core collapses to form either a black hole or a neutron star.
SNR G292.0+1.8 Identify the elements in this SNR.
SNR G292.0+1.8 Hughes, et al 2001
Using an energy cut from 2-7 KeV can help you see the central core. SNR G292.0+1.8 “Hard-band” x-ray image (energy cut from 2-7 KeV) pulsar?
From “Imagine! The Universe: “The observed elements and abundances are very different for different type of SN explosions (massive star vs. white dwarf). Type Ia remnants (from white dwarfs) should have relatively strong Si, S, Ar, Ca, and Fe, and weak O, Ne, and Mg; Type II (from massive stars) generally have the reverse pattern.” SNR G292.0+1.8 Tycho’s SNR
Cas A OBS ID 114
Cas A Identify the elements in this SNR. What type do you think it is?
Cas A in Color Can you find the central point-like X-ray source in the last image? These images were creating by making “energy cuts” in ds9, choosing a different color scheme for “soft”, “medium” and “hard” x-rays (red, green and blue, respectively) and then overlapping them as transparent layers in Adobe Photoshop to create a three-color composite image.