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c.s. briar

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Neutron stars are AWESOME!

A neutron star forms when the core of a giant star collapses in a supernova, leaving a sphere about 20 kilometers in diameter, with a mass greater than that of the sun. The microscopic structure of the outer crust is a lattice of neutron-rich nuclei surrounded by a uniform gas of electrons. As you move toward the star’s center, the increasing pressure fuses more and more electrons and protons into neutrons, increasing the neutron density in the nuclei. Eventually, in the inner crust, the nuclei cannot accept any more neutrons, and free neutrons form a superfluid that permeates the lattice.

The crust of a neutron star makes up only a fraction of the star’s mass, but it significantly influences phenomena such as the cooling rate and the production of dramatic gamma-ray flashes. Publishing in Physical Review Letters, a pair of theorists has found that the structure that astrophysicists have assumed for decades is unstable. If the results are correct, theorists will need to recalculate many of the basic properties of neutron stars. There is also a chance that these objects are a stronger source of potentially detectable gravitational radiation than anyone previously expected.
Deformations and cracks in the crusts of neutron stars have been linked with phenomena such as gravitational waves, bursts of gamma rays, and “glitches”—events where a star’s spin suddenly speeds up. The inner crust’s structure is key to understanding these events.

Theorists have examined many aspects of the inner crust, for example, analyzing vibrations of the lattice. “This matter has been studied since the 1970s,” says Dmitry Kobyakov of Umeå University in Sweden. The structure of the inner crust has been modeled as a lattice in a so-called body-centered-cubic (bcc) formation—each cubic unit of the crystal has nuclei at the center and at its eight corners—with an electron gas circulating throughout the structure. But the free neutrons were thought to have little effect.

In their new model, Kobyakov and Christopher Pethick of the University of Copenhagen and NORDITA in Stockholm have accounted for the interactions between the free neutrons and the lattice. They found that the neutrons are somewhat analogous to an additional component in a metallic alloy and that they lead to an effective attraction between nuclei. This attraction turned out to have dramatic effects on the crust’s response to short-wavelength lattice vibrations.

The lattice constantly jiggles with vibrations having a wide range of wavelengths. For wavelengths shorter than about 2 to 5 times the lattice spacing, the team found that the system is unstable—a lack of rigidity causes vibrations to grow steadily in size. The instability implies that the usual assumption of the bcc crystalline arrangement of nuclei is incorrect, says Kobyakov.

“A lot of our models might need to be modified and quite possibly even thrown out,” says Edward Brown, an astrophysicist at Michigan State University in East Lansing. “If the lattice structure is different, then a lot of properties need to be recalculated. There’s potentially a lot of rich physics.”

The structure of the inner crust affects the crust’s strength and rigidity, which can have major implications for a star’s behavior. For example, if the crust of a neutron star is sufficiently strong, it can support mountain-like structures on its surface. As it spins—neutron stars can twirl more than 600 times per second—these mountains create ripples in spacetime known as gravitational waves, which may be detectable by the Laser Interferometer Gravitational-Wave Observatory (LIGO), the facility attempting to make the first direct detections of these waves. “The crust could be much more rigid than we thought and could support a much larger mountain, in which case these are a much more interesting target for LIGO,” says Brown.

Such a rigidity increase would also influence earthquake-like ruptures in the crust that may be related to the bursts of gamma rays observed from magnetars (highly magnetic neutron stars). Researchers studying these and other phenomena may need to look closely at the new results, says Brown. “It could change things a lot, or it could end up modifying things just a little bit.”

–Sophie Bushwick
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c.s. briar

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A new particle  Zc(3900), has been found to contain 4 quarks rather than the normal pairing of 2 or 3. Quarks are the most basic building blocks of matter that we know of to date, so it is exciting to know that we are one step closer to the big picture. It's also exhilarating because  there's still so much learn !

"Until now, observed particles made of quarks have contained only three quarks (such as protons and neutrons) or two quarks (such as the pions and kaons found in cosmic rays). Although no law of physics precludes larger congregations, finding a quartet expands the ways in which quarks can be snapped together to make exotic forms of matter.

The Belle detector monitors collisions between intense beams of electrons and their antimatter counterparts, positrons. These crashes have one-thousandth the energy of those at the world’s most powerful accelerator, the Large Hadron Collider (LHC) at CERN near Geneva, Switzerland, but they are still energetic enough to mimic conditions in the early Universe. Collision rates at KEK are more than twice those at the LHC, and they occasionally give birth to rare particles not found in nature today — ephemeral creatures that wink into existence for an instant and then fall to pieces.

Some of that subatomic shrapnel matches what would be expected from the breakdown of a particle containing four quarks bound together: two especially heavy ‘charm’ quarks and two lighter quarks that give the particle a charge. "

Click the link to read more.
First particle containing four quarks is confirmed.
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Slow Motion Popping Popcorn!
#popcorn   #slowmotion  
 
Popping Popcorn in super Slow Motion

#gif   #slow_motion   #science  
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Andrene Keefe

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Thank you for the invite.
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TIGA MusicPoland

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Thanks for the invite :)
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Luís Guilherme

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Thank you for the invite.  I appreciate it.
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Total Lunar Eclipse!
#eclipse   #science   #lunareclipse   #totallunareclipse  
 
A total lunar eclipse is about to happen, here's how you can watch: http://engt.co/1p4GktO
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Nice! 
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Fractals!
#science   #fractals  
 
A Lindenmeyer System is a grammar with simple recursive rules, which produce strings of symbols that can be interpreted as graphics commands in programs such as Python or Turtle to draw a line, turn by a certain angle, etc. The result of various grammars and ways to interpret them can be quite beautiful fractal images. +Andreas Wilhelm, a German Applied Computer Science BSc. who blogs about Computer Science and Math, has been making art using L-Systems (en.wikipedia.org/wiki/L-system). His blog, avedo.net/554/lindenmeyer-systems-a-python-adventure/ describes his work with plenty of interesting examples. Thanks to +Appropouture for finding the animation I posted here, which comes from verbalairways.tumblr.com.
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Inner Earth: How the Planet Works!
#science   #earth  
 
This is how the planet works: http://pops.ci/1lNCEKK
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these pictures always bug me a bit...

I know the core of the planet is hot and the colour is supposed to represent that, but:

The Mantle is made of forsterite/fayerite and pyroxenes - Iron silicates - and they are (olive) green

The Core is mostly made of Nickel/Iron metal, and is shiny silvery grey

so, basically like most Meteorites - either green or metal.
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About this community

Sharing cutting-edge science on Google+! Note: This Community is in no way associated with Google, Inc. Just fans of their technology sharing and learning. Thanks Google! =)
 
Worn tires soon to be recycled as material for new roads http://goo.gl/8n5m3d

#sustainabledevelopment #environmentalengineering
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c.s. briar

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Amber is a vitrified resin valued for its beauty and the intriguing specimens occasionally trapped within it. Now, scientists are studying ancient amber samples to determine how their glasslike properties change with time. Amber is a unique example of a glass because it has “hyperaged,” i.e., has undergone thermodynamic stabilization for millions of years—a process that is impossible to replicate in a lab.

Conventional, nonhyperaged glasses characteristically exhibit a so-called boson peak—an enhancement in the density of vibrational states over that expected for a crystalline solid. As reported in Physical Review Letters, Miguel Ramos at the Autonomous University of Madrid, Spain, and his collaborators used 110-million-year-old Spanish amber samples to investigate how the boson peak changes as the amber samples are subjected to thermal annealing, which effectively de-ages them. Previous studies suggested that the strength of the boson peak diminished with annealing, although the samples that were tested had only cooled for moderately short laboratory time scales.

Ramos and his team measured the specific heat of several amber samples, comparing specimens of pristine hyperaged amber, samples that had been annealed at temperatures below and around their glass transition temperature, and “rejuvenated” amber that had been heated well above its glass transition temperature. The annealed samples represented glasses with partially erased thermal histories, while the rejuvenated amber had had its 110-million-year cooling cycle effectively erased. The authors found that the specific heats of all the samples were identical within the experimental errors for temperatures below 1 kelvin. This finding implies that the boson peak and other thermodynamic properties remain fossilized in the glass—much like a trapped insect—and are unchanged by more than 100 million years of aging. – Katherine Kornei
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c.s. briar

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Feynman, one of the greatest minds of last century. Do you know why he is so important?
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Laban Newmei Newmei

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Thanks for the invite:)
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Devon Reed

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What is a scientific explanation of the sun's apparent movement ? 
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Jacqueline Förster

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Thanks 4 the invite :D
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MaLou S Santos

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Thank you for the invite.  I appreciate it.
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Cool Science - Pouring an Ice Cube!
#science   #chemistry  
 
Pouring an ice cube using supercooled water: The temperature of the liquid water is reduced below its freezing point, without becoming a solid. The ice won't form without the presence of a nucleation point (a crystal or impurity around which an ice crystal can begin to grow). However, on contact with another surface, the water instantly freezes. Check out how to make instant ice at home in this video: http://youtu.be/sBFK5-JvBAc
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c.s. briar

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You've gotta love a crash course, especially when it's about sleep. Sweet dreams everyone:) 
 
Why do we sleep? Well... that's a tricky question. More easily answered is the question,"How do we sleep?" In this episode of Crash Course Psychology, +Hank Green  discusses some of the ways our brain functions when sleeping and how it can malfunction as well.

To Sleep, Perchance to Dream - Crash Course Psychology #9
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Inside the Brain: Unraveling Alzheimer's: Tau protein and Amyloid beta plaques!
#brain   #science   #neuroscience   #alzheimers   #disease  
 
Unraveling Alzheimer's: Tau protein and Amyloid beta plaques
I used this NIH animated clip in compiling my presentation that detailed my lab project & rotation in Neuroscience. It's a very informative and educational animation that I showed to my Bioethics & Science Communications classmates.
#Science #Alzheimers #Amyloid #Tau #NIH #Education #Animation
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Space Elevators?
#space   #tech   #science  
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Brian Gauspohl's profile photoScott Parker's profile photoEerik Owerhall's profile photoBedhan Ball's profile photo
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And...On the 20 thousandth floor we have...
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