Solar Flares gives antimatter

Erupção solar captada pela SOHO em 28 de outubro de 2003 (NASA / SOHO)

Associated with solar magnetic storms, solar flares are giant explosions on the sun that send energy, light and particles in all directions to the space. Their number increases approximately every 11 years.

When the universe was formed 13.8 billion years ago in the event known as the Big Bang, there was the same amount of matter and antimatter. Somehow the matter antimatter annihilated (when matter and antimatter meet, they annihilate each other), leaving only a portion of matter, enough to form stars, planets and galaxies that make up our universe.

The study of natural sources of antimatter, will allow researchers to understand why antimatter lost the battle to matter in the beginning of our universe.

Positrons are antiparticles of the antimatter. The positron, e⁺, and electrons, e^-, (populating the common atoms) have the same physical behavior, except that the electrons have a negative charge while the positrons, as its name indicates, have a positive charge. This charge's difference causes that positrons interact differently with electromagnetic fields, which Professor Gregory Fleishman, from the New Jersey Institute of Technology and his colleagues from the Russia's Institute of Solar-Terrestrial Physics used to distinguish them.

The process of solar flares are very energetic and the ejected mass accelerates particles to speeds approaching the speed of light, allowing the creation of these positrons.

Using data from SOHO and radio images of two different frequencies obtained from Japan's Nobeyama Radioheliograph, the Russian-American team found that the light was polarized in different directions for low frequencies, where the ordinary matter dominates, compared to higher frequencies where antimatter is more expected.

"That this kind of antiparticles are created in solar flares is not surprising, but this is the first time that the immediate effects are detected," these results were presented on July 8, at the 44th meeting of Society American Astronomical Society's Solar Physics Division of the Bozeman, Montana.

The study has profound implications for obtaining valuable knowledge through remote sensing antiparticles relativistic starting the Sun and possibly other astrophysical objects through observations of radio telescopes.

Sources: sci-news, space.com, dailygalaxy

What happened to antimatter? - Rolf Landua

Me and Rolf Landua holding the antimatter container of DaVinci's Code

Do you remember the antimatter bomb in the DaVinci's Code movie?

In my journey at CERN, Rolf Landua gave a lecture about antimatter. Basically the topics in the lecture was this questions: What is it? Where is it create? How can be created? What is the mystery behind it? How can we study it? Can we use it as a energy font or a bomb? Is any antimatter in our daylife?

In particle physics, antimatter is material composed of antiparticles, which have the same mass as particles of ordinary matter but have opposite charge and quantum spin. Antiparticles bind with each other to form antimatter in the same way that normal particles bind to form normal matter. For example, a positron (the antiparticle of the electron, with symbol e+) and an antiproton (symbol p) can form an antihydrogen atom. Furthermore, mixing matter and antimatter can lead to the annihilation of both, in the same way that mixing antiparticles and particles does, thus giving rise to high-energy photons (gamma rays) or other particle–antiparticle pairs. The end result of antimatter meeting matter is a release of energy proportional to the mass as the mass-energy equivalence equation, E=mc² shows.

At this time, the apparent asymmetry of matter and antimatter in the visible universe is one of the greatest unsolved problems in physics.

Antimatter is created in the LHC, and the LHCb is the detector responsible to detect particles in the antiprotons' collisions. The antiprotons' production is achieved with the collisions between protons and nucleus of Iridium, Cupper, and others. The antiprotons are decelerated and keep trapped with a combination of electric and magnetic fields (so it doesn't touch matter). In this way, the resultant material is detected by the detector before the annihilation. That event is one of the biggest mysteries of the Big Bang, and scientist are trying to answer it: the domination of the matter over the antimatter.

FDG is a glucose molecule, with fluorine-18 attached

This antimatter cannot be used as energy or weapon because we need energy to create it. Imagine that we want to produce 0.5 g of antimatter. Well, we need 22 kton (22,000 ton) of TNT (almost the same value of the Hiroshima's bomb), to produce 0.5 g of matter and antimatter. The energy in this process is about 4.5 x 10¹³ J. The total energy that we need (because the efficiency is 10^-9 %) will be 4,5 x 10²² J. Even with CERN's discount made by French Electric Company [1 kwh = 3,6 x 10⁶ J= 0,1 €], the total cost will be 1 x 10⁸ € and it will be take a billion years to produce and supply this production to CERN.

But, antimatter is used in our body for PET scan detection. The glucose has a fluorine-18 attached that will emit positrons when that molecule travels in our body, and the scanner detects where the positrons go.

The next step that scientist at CERN are trying to develop is to use positrons and antiprotons as therapy in some deceases.

References:

• Antimatter - Wikipedia
• Having a Pet Scan
• Antimatter presentation - Rolf Landua, CERN

ScienceCasts: A Whiff of Dark Matter on the ISS

In astronomy and cosmology, dark matter is a type of matter hypothesized to account for a large part of the total mass in the universe. Dark matter cannot be seen directly with telescopes; evidently it neither emits nor absorbs light or other electromagnetic radiation at any significant level. Instead, its existence and properties are inferred from its gravitational effects on visible matter, radiation, and the large-scale structure of the universe. According to the Planck mission team, and based on the standard model of cosmology, the total mass–energy of the universe contains 4.9% ordinary matter, 26.8% dark matter and 68.3% dark energy. Thus, dark matter is estimated to constitute 84.5% of the total matter in the universe.

On 3 April 2013, NASA scientists reported that hints of dark matter may have been detected by the Alpha Magnetic Spectrometer on the International Space Station. According to the scientists, "The first results from the space-borne Alpha Magnetic Spectrometer confirm an unexplained excess of high-energy positrons in Earth-bound cosmic rays."

font: wikipedia

To know more about dark matter and dark energy follow this link: http://home.web.cern.ch/about/physics/dark-matter

CERN press release:

Geneva 3 April 2013. The international team running the Alpha Magnetic Spectrometer (AMS) today announced the first results in its search for dark matter. The results, presented by AMS spokesperson Professor Samuel Ting (...). They report the observation of an excess of positrons in the cosmic ray flux.

The AMS results are based on some 25 billion recorded events, including 400,000 positrons with energies between 0.5 GeV and 350 GeV, recorded over a year and a half. This represents the largest collection of antimatter particles recorded in space. The positron fraction increases from 10 GeV to 250 GeV, with the data showing the slope of the increase reducing by an order of magnitude over the range 20-250 GeV. The data also show no significant variation over time, or any preferred incoming direction. These results are consistent with the positrons originating from the annihilation of dark matter particles in space, but not yet sufficiently conclusive to rule out other explanations. [...]