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View Full Version : Rare Binary Pulsars Provide High Energy Physics Lab



Fraser
2008-Jun-23, 07:50 PM
For the first time, a spacecraft has detected signals from both stars of a binary pulsar system in X-rays. XMM-Newton is watching both stars radiate pulsating X-rays, providing scientist with the perfect laboratory for high-energy physics and a never-ending source of intriguing physical problems. The binary pulsar PSR J0737-3039 was first spotted by [...]

More... (http://www.universetoday.com/2008/06/23/rare-binary-pulsars-provide-high-energy-physics-lab/)

antoniseb
2008-Jun-23, 08:52 PM
It is interesting to read a followup on this system. When it was first announced it seemed like an incredibly good find for studying general relativity. It's nice to see more details, and to read that XMM Newton is giving us even more details.

RussT
2008-Jun-24, 01:35 AM
It is interesting to read a followup on this system. When it was first announced it seemed like an incredibly good find for studying general relativity. It's nice to see more details, and to read that XMM Newton is giving us even more details.

Allow me to pull out my Tea Leaves and predict that Trinitree88 will be along shortly...;>)

If Pulsars are Neutron stars that get a sizable 'kick' to be removed from the Nebula...then how can two Pulsars be "Binary"??? UMMMMMMMMmmmmmm.

trinitree88
2008-Jun-24, 04:21 PM
Allow me to pull out my Tea Leaves and predict that Trinitree88 will be along shortly...;>)

If Pulsars are Neutron stars that get a sizable 'kick' to be removed from the Nebula...then how can two Pulsars be "Binary"??? UMMMMMMMMmmmmmm.

Russ T. Tea with a twist of lemon or lime?...or a touch of cream & sugar?

The existence of pulsar binaries is known, so elucidating the capture will be the trick. Ejection from birthplaces ranges from the tens of kilometers per second to the high hundreds of kilometers per second, and the record was just under 1% the speed of light (Shrinivas Kulkarni and Dale Frail). It has recently been shown that Cepheids pulsate with their longitudinal axes in cohort in galaxies, indicating galactic magnetic fields play a role in aligning them. Inferred is the result that OB associations in galaxies will have similar alignments, leading to pulsar ejection velocities spatially similar. That would mean that the pulsars with less-than-escape-velocities...(somewhere around 280/km/sec...it varies depending on the supernova progenitor's location in the host galaxy's gravitational well)...will eventually be running out of "steam" like Fourth of July sky-rockets...and will slow in the galactic halo at hundreds of kiloparsecs, before falling back through the disk. Two nearby pulsars should eventually have an opportunity to capture each other at low peripheral velocities...though certainly the statistics are tiny.
One of the things they can search for with better instrumentation is polar emission of helium multiples...isotopes of elements that are integral multiples of helium's atomic mass. Nuclear studies have shown that radioactive elements decay with alpha decay (a single helium nucleus, atomic number 2, mass number4)..or as beryllium-8 (a double alpha)...or as carbon 12 (a triple alpha). Some of this nuclear tendency should carry over to pulsars. Why?
Pulsars have been seen leaving "tails" (Fraser's old post), and the neutron is a particle that has a variable half-life depending on the ambient magnetic field strength. Grade school texts say that "nothing" affects the radioactive half-life, but that's not true. The half life drops precipitously when the field strength approaches 1011 to 1013 Gauss...conveniently the observed strength of pulsars. So the pulsar jets out it's decay products a bit, like a balloon let go at a child's birthday party. Indications are that merging pulsars can greatly enhance this effect with fields being surmised at approaching 1018Gauss, surpassing that of even magnatars. see:http://209.85.141.104/search?q=cache:YDupUXrzi08J:www.faculty.iu-bremen.de/srosswog/price_rosswog_web.pdf+neutrons+unstable+in+high+ma gnetic+fields&hl=en&ct=clnk&cd=2&gl=us

Now, ...crumpets with the tea? scones? maccaroons? pete

RussT
2008-Jun-25, 11:34 PM
Russ T. Tea with a twist of lemon or lime?...or a touch of cream & sugar?

The existence of pulsar binaries is known, so elucidating the capture will be the trick. Ejection from birthplaces ranges from the tens of kilometers per second to the high hundreds of kilometers per second, and the record was just under 1% the speed of light (Shrinivas Kulkarni and Dale Frail). It has recently been shown that Cepheids pulsate with their longitudinal axes in cohort in galaxies, indicating galactic magnetic fields play a role in aligning them. Inferred is the result that OB associations in galaxies will have similar alignments, leading to pulsar ejection velocities spatially similar. That would mean that the pulsars with less-than-escape-velocities...(somewhere around 280/km/sec...it varies depending on the supernova progenitor's location in the host galaxy's gravitational well)...will eventually be running out of "steam" like Fourth of July sky-rockets...and will slow in the galactic halo at hundreds of kiloparsecs, before falling back through the disk. Two nearby pulsars should eventually have an opportunity to capture each other at low peripheral velocities...though certainly the statistics are tiny.
One of the things they can search for with better instrumentation is polar emission of helium multiples...isotopes of elements that are integral multiples of helium's atomic mass. Nuclear studies have shown that radioactive elements decay with alpha decay (a single helium nucleus, atomic number 2, mass number4)..or as beryllium-8 (a double alpha)...or as carbon 12 (a triple alpha). Some of this nuclear tendency should carry over to pulsars. Why?
Pulsars have been seen leaving "tails" (Fraser's old post), and the neutron is a particle that has a variable half-life depending on the ambient magnetic field strength. Grade school texts say that "nothing" affects the radioactive half-life, but that's not true. The half life drops precipitously when the field strength approaches 1011 to 1013 Gauss...conveniently the observed strength of pulsars. So the pulsar jets out it's decay products a bit, like a balloon let go at a child's birthday party. Indications are that merging pulsars can greatly enhance this effect with fields being surmised at approaching 1018Gauss, surpassing that of even magnatars. see:http://209.85.141.104/search?q=cache:YDupUXrzi08J:www.faculty.iu-bremen.de/srosswog/price_rosswog_web.pdf+neutrons+unstable+in+high+ma gnetic+fields&hl=en&ct=clnk&cd=2&gl=us

Now, ...crumpets with the tea? scones? maccaroons? pete

Nice presentation...;>)

Thanks, but I am more of a iced/hot white mocha and chocolate eclair/maple bar with custard filling kind of guy...;)...yeah, and meat and potatoes too...I know...my bad.

The "Capture" without merger (How in the world could that even happen?) or collision should be a real GR doosie...

Here is an unrelated general question for you...

What are the 'energy levels'/energy signatures of all the different ranges of Neutrinos that we can detect?