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  • May 23, 2017
  • 07:06 AM
  • 51 views

Multi-Loop Structure of Nonthermal Microwave Sources in a Major Long-Duration Flare by V. Grechnev et al.*

by CESRA in Solar Radio Science

Hard X-ray (HXR) and microwave observations of flares show only a few nonthermal sources. They are simple and compact, especially in impulsive flares, suggesting involvement of one to two loops. Hanaoka (1996) and Nishio et al. (1997) interpreted these observations in terms of double-loop flares. This view was later extended up to long-duration flares (Tzatzakis, Nindos, and Alissandrakis, 2008). A concept of a simple flare loop became dominant. However, observations [...]... Read more »

  • May 16, 2017
  • 07:04 AM
  • 11 views

Comparison of alternative zebra-structure models in solar radio emission by G.P. Chernov et al.*

by CESRA in Solar Radio Science

Discussion about the nature of zebra-structure (ZS) in type IV radio bursts continues, despite the ten proposed models. First of all, this is due to the wide variety of stripes in each new phenomenon, making the explanation of all the fine details by any one mechanism becomes impossible. The most widespread explanation is the emission at different levels of double plasma resonance (DPR), sequential on the height surfaces in the magnetic [...]... Read more »

G. P. Chernov, V. V. Fomichev, & R. A. Sych. (2017) Comparison of alternative zebra-structure models in solar radio emission. submitted to Astronomy Letter Journal. arXiv: 1704.02528v1

  • May 9, 2017
  • 07:07 AM
  • 176 views

Microwave emission as a proxy of CME speed in ICME forecasting by Carolina Salas Matamoros, Ludwig Klein and Gerard Trottet

by CESRA in Solar Radio Science

Coronal Mass Ejections (CMEs) are one type of interplanetary structure that mostly affect the geomagnetic field (e.g. Gonzalez and Tsurutani, 1987; Zhang et al, 2007). These structures are observed and studied through coronagraphic images. The basic limitation of the coronagraph is that it shows the corona only in the plane of the sky, and blocks by necessity the view on the solar disk. Thus, the projection effect in the kinematic [...]... Read more »

  • April 25, 2017
  • 07:02 AM
  • 206 views

The Brightness Temperature of the Quiet Solar Chromosphere at 2.6 mm by Kazumasa Iwai et al

by CESRA in Solar Radio Science

The brightness temperature of the Sun constitutes a basic property of the solar atmosphere. The main emission mechanism of the Sun at millimeter and submillimeter wavelengths is thermal free–free emission from the chromosphere, which is an atmospheric layer with a temperature ranging between 6000 to 20,000 K. The opacity of thermal free–free emission depends on the temperature and density in the emission region. In addition, the Rayleigh– Jeans law is applicable [...]... Read more »

Iwai, K., Shimojo, M., Asayama, S., Minamidani, T., White, S., Bastian, T., & Saito, M. (2017) The Brightness Temperature of the Quiet Solar Chromosphere at 2.6 mm. Solar Physics, 292(1). DOI: 10.1007/s11207-016-1044-5  

  • April 14, 2017
  • 08:58 AM
  • 297 views

Well below 1%

by Marco Frasca in The Gauge Connection

When a theory is too hard to solve people try to consider lower dimensional cases. This also happened for Yang-Mills theory. The four dimensional case is notoriously difficult to manage due to the large coupling and the three dimensional case has been treated both theoretically and by lattice computations. In this latter case, the ground […]... Read more »

Andreas Athenodorou, & Michael Teper. (2017) SU(N) gauge theories in 2 1 dimensions: glueball spectra and kstring tensions. J. High Energ. Phys., 15. arXiv: 1609.03873v1

Marco Frasca. (2015) Quantum Yang-Mills field theory. Eur. Phys. J. Plus (2017) 132: 38. arXiv: 1509.05292v2

  • April 11, 2017
  • 09:00 AM
  • 330 views

Looking for clues for past life on Mars

by EE Giorgi in CHIMERAS

NASA's Curiosity Mars. Credits: NASA/JPL-Caltech/MSSSOn August 6, 2012, the NASA Curiosity rover landed on Mars at the base of Mount Sharp, a mountain the size of Kilimanjaro (~19,000 feet) in the middle of Gale Crater. Nina Lanza, space scientist at the Los Alamos National Laboratory, remembers the day well. As part of the team that built ChemCam, one of the ten instruments on the rover, she spent three months at the Jet Propulsion Laboratory in California, living on “Mars time” to follow Curiosity’s first “steps.” ChemCam stands for “chemistry camera” and comprises a laser-induced breakdown spectroscopy (LIBS) instrument and a Remote Micro Imager (RMI). It was built at the Los Alamos National Laboratory in collaboration with the French space agency CNES. Nina Lanza and postdoctoral fellow Patrick Gasda are two of the Los Alamos scientists who work on the instrument. “We get to shoot a laser on Mars for a living,” Lanza says, grinning.And the laser on ChemCam is extremely powerful. When focused on a target, it vaporizes a small amount of material by heating Martian rocks to a temperature that’s roughly equivalent to that of the surface of the sun. “When we fire at a nearby target,” Gasda explains, “the elements get excited and, as they come down from that excited state, they emit light.”By looking at the light emitted by the target, scientists can analyze the composition of rocks and soils on Mars. Previous Mars missions have found ice in the near-surface at high latitudes, begging the question: was there ever water on other parts of Mars at some point? And if there was—does that mean there could have been life, too?With the very first laser shots from ChemCam, the answer was a definitive yes. “ChemCam discovered that all Martian dust is hydrated,” Lanza explains. “Given how dusty Mars is, this means that water is everywhere on the planet. We also found evidence that water was flowing in Mars’s past.” “Gale Crater was filled with water,” Gasda adds. “From the sequence of sedimentary rocks we know of flowing streams in the crater that converged to a large body of still water that likely lasted for millions of years.”“Curiosity gave us a picture of Gale Crater as an extremely habitable system,” Lanza continues. “We know that on Earth systems like this, with long-lasting neutral pH waters, would definitely support life.”But how do you go about finding evidence for life? You search for clues, in other words, unique markers that identify biological activity.“A potential marker could be manganese minerals,” Lanza says. In 2016 Curiosity found rocks rich in manganese-oxides at a location called Kimberley. “Manganese deposits in the terrestrial geological record mark the shift to higher concentrations of atmospheric oxygen due to the emergence of photosynthesis. This means that there could have been more oxygen in the Martian atmosphere in the past.” Water. Oxygen. What about other building blocks of life? How do we look for those?“Nucleic and amino acids have been found in space,” Gasda tells me. “However, ribose—the ‘R’ in RNA, one of the first building blocks of life—and other sugars have never been found in space because they are too unstable. In order to have life, you need molecules that stabilize these sugars in water. Borates are particularly promising molecules for stabilizing sugars [1].”Boron is highly soluble in water. In 2013 researchers from the University of Hawaii found boron in a meteorite from Mars [2]. That’s when Gasda became interested in this quest. “Once we knew that Gale Crater had once hosted a large body of water, it was natural to search for boron in those sediments.” ChemCam did indeed find boron on Mars in 2016. Together with the manganese oxides, this is still not sufficient evidence for life on Mars, but it shows that some of the raw ingredients were present. The scientists are primed to keep looking. Curiosity has been on Mars almost five years (or 1660 sols), and its data is helping researchers fine-tune the instruments for the next Mars rover, provisionally named Mars 2020, to be launched in July 2020. “We need to look for biosignatures,” Lanza says. “And we may not find them. But if we don’t, to me, the most striking question would be: what if there were indeed all the ingredients for life on Mars, yet life never happened? What made Earth so unique that life could happen here but nowhere else?”Gasda nods. “And if we are indeed unique, shouldn’t this make us feel more special, and make us more cautious about the way we treat our planet and our biodiversity?” I mention the current political climate, with the planned budget cuts to scientific research, and the appalling denial of any intervention to curb global warming. “These cuts to basic research are disheartening,” Lanza says. “People often think of NASA research as esoteric and out of touch. And yet almost everyone has GPS technology on their smart phones today, something we owe to space research. Take the electron as another example. I’m sure people in the nineteenth century found J. J. Thomson’s research on the electron to be highly academic, with few practical applications. Yet without his discovery we wouldn’t have electricity, and our lives today would be fundamentally different.” “The best measure for progress,” Lanza concludes, “is when you can’t imagine the knowledge you are going to gain. Let the science surprise you.” Nina Lanza is a staff scientist, and Patrick Gasda is a postdoctoral research fellow, both in the Space and Remote Sensing group at the Los Alamos National Laboratory. They are both on the science team for the Curiosity Mars rover mission. The opinions expressed here are their own and not their employer’s. Both will be speaking at the March for Science in Santa Fe, New Mexico, on April 22nd. [1] Ricardo, A. (2004). Borate Minerals Stabilize Ribose Science, 303 (5655), 196-196 DOI: 10.1126/science.1092464[2] Stephenson, J., Hallis, L., Nagashima, K., & Freeland, S. (2013). Boron Enrichment in Martian Clay PLoS ONE, 8 (6) DOI: 10.1371/journal.pone.0064624... Read more »

Ricardo, A. (2004) Borate Minerals Stabilize Ribose. Science, 303(5655), 196-196. DOI: 10.1126/science.1092464  

Stephenson, J., Hallis, L., Nagashima, K., & Freeland, S. (2013) Boron Enrichment in Martian Clay. PLoS ONE, 8(6). DOI: 10.1371/journal.pone.0064624  

  • April 11, 2017
  • 06:34 AM
  • 289 views

How Electron Beams Produce Continuous Coherent Plasma Emission by H. Che, M. Goldstein, P. Diamond, and R. Sagdeev

by CESRA in Solar Radio Science

It is commonly accepted that energetic electron beams can produce drift frequency radio emission or Type III bursts since Ginzburg and Zhelezniakov first proposed the idea in 1958. However, the electron two-stream instability time (see reference 2) in the corona is fraction of a second, while the duration of coronal Type III bursts lasts several orders of magnitude longer. This problem is called the “Sturrock Dilemma” and remains a subject [...]... Read more »

  • April 3, 2017
  • 09:00 AM
  • 264 views

"Science is Under Attack." A Climate Scientist's Call to Action for the Future of our Planet.

by EE Giorgi in CHIMERAS

It’s a foggy morning in London. Meteorologist George Simpson, the director of the British Meteorological Office, sips his tea and opens a paper authored by a scientist named Guy Stewart Callendar. The last sentence of the abstract reads, “The temperature observations at 200 meteorological stations are used to show that world temperatures have actually increased at an average rate of 0.005°C per year during the past half century.”Simpson shakes his head and thinks, “Nonsense. It’s all a coincidence.”If this seems like a modern-day scene over climate change, you’ll be surprised to know that Callendar published his paper in 1938. And of course, his results, linking a global trend in temperature rises to atmospheric carbon dioxide concentrations, were received with a lot of skepticism. Almost 80 years later the debate is still ongoing.“It is disheartening,” says Todd Ringler, climate scientist currently working at Los Alamos National Laboratory. “The reality is that there is no uncertainty about the basic premise of climate change. We know that CO2 concentrations are rising, we know why they are rising, and we know that CO2 tends to warm the atmosphere.”In fact, this last effect — that CO2 warms the atmosphere — was shown by Irish physicist John Tyndall in 1859, over 150 years ago. But if the science on CO2 and its effect has been clear for so long, why does the public still have this preconception of uncertainty when it comes to global warming and climate change?“There is essentially no doubt that temperatures are rising because of CO2 concentrations,” Ringler explains. “The biggest uncertainty controlling global temperature in year 2100 is what our energy future will look like. In other words, we cannot estimate how much the temperatures will rise until we decide how dependent we want to be on fossil fuels going forward.”“Basically what you’re saying,” I interject, “is that the largest uncertainty here is human behavior, because we still haven’t made up our mind on what, if anything, we want to do about global warming.”“Exactly. I recently republished an op-ed I wrote ten years ago on the science and politics of global climate change,” Ringler says. “Unfortunately, 10 years later, the debate hasn’t changed, but all this litigation on the basic science is futile. The science is established, now we need to discuss policies.”In his op-ed, Ringler has some stern words for our leaders: “Our government was failing us 10 years ago, and it's still failing us today by moving steadily away from a position of international leadership for crafting a comprehensive policy framework.”“Why do you believe we still can’t come up with an agreement on this?” I ask.Ringler sighs. “Humans have a long history of learning by experience, by trial and error. Take vaccines, for example. When we stop vaccinating, pockets of outbreaks resurface to remind us why we invented vaccines in the first place. Climate change happens over such a long time scale and carbon stays in the atmosphere for such a long time that we don’t have the luxury of learning by trial and error here. We have to get this right the first time, and we are not good at that. Day-to-day the biggest challenge we are facing when it comes to climate change is that we cannot pin down any single event to global warming. Weather is by its own nature random, but what global warming is doing is making certain random outcomes more likely than others. It’s shifting the roll of a dice, so to speak.”And taken all together, these “random” events scattered across the globe are indeed making an impact: the ice caps have been steadily shrinking for the past 38 years of satellite records; the increasing amounts of CO2 retained by sea water are causing ocean acidification, harming marine organisms; weather patterns are becoming more severe, with stronger floods and longer droughts.“What do you see as the biggest challenge posed by the current administration?”“The current administration is ideologically opposed to regulations. But we need some rules, whatever they look like, to limit the amount of carbon in the atmosphere. Look, renewable energy is happening. Take Texas, for example, which is pioneering wind energy. Las Vegas is now mostly powered by clean energy. The very same oil companies we often think of as opposing regulations on carbon missions are actually advocating for us to take action. But the problem is global and as such it requires global agreements and global solutions. It does matter what country emits the carbon, the carbon harms everyone. All nations need to come together and share the opportunities and costs of transitioning away from fossil fuels. What the current administration needs to understand is that what they see as ‘regulations’ are in fact ‘protections’ that we need to put forward to safeguard our future and our children’s future.”“What pains me the most,” Ringler continues, “is the disconnect between science and policy. We have this disconnect between knowing something and acting accordingly. Knowledge has lost its primary role in our society, and now science is under attack. This is not healthy. A healthy society is one in which the knowledge we gather through science informs the policy making.”As Ringler wrote in his op-ed, “We owe it to ourselves and to future generations to ask the following question: What if our present understanding of global climate change is correct? What does this mean for our society? What will happen to water in the already arid West? What will happen to agriculture, both here and around the world? Can developing nations accommodate these changes? And if not, how will we deal with the climate-driven conflict that will surely follow?”Dr. Todd Ringler has 25 years of experience modeling the climate of the atmosphere and ocean. He studied at Cornell and Princeton University, then joined the research faculty at Colorado State University and is presently a scientist working at Los Alamos National Laboratory. He is member of the International CLIVAR Ocean Model Development Panel and a long-time advocate for sensible solutions to address climate change impacts. The views and opinions expressed here are Todd Ringler’s own thoughts on this subject. He will be speaking at the March for Science in Santa Fe, New Mexico on April 22nd. REFERENCES[1] Callendar, G. (1938). The artificial production of carbon dioxide and its influence on temperature Quarterly Journal of the Royal Meteorological Society, 64 (275), 223-240 DOI: 10.1002/qj.49706427503... Read more »

  • March 28, 2017
  • 08:04 AM
  • 253 views

Radio Diagnostics of Electron Acceleration Sites During the Eruption of a Flux Rope in the Solar Corona by Eoin Carley et al.*

by CESRA in Solar Radio Science

Flares and coronal mass ejections (CMEs) are thought to result from magnetic energy release in the solar corona, often involving the destabilisation of a twisted magnetic structure known as a flux rope (Chen et al. 2011, Webb et al. 2012). This activity may be accompanied by the acceleration of electrons (Kahler 2007, Lin et al. 2011). However, there is ongoing debate on exactly where, when and how this particle acceleration occurs [...]... Read more »

  • March 27, 2017
  • 01:05 PM
  • 66 views

Cosmic Dopamine: On "Neuroquantum Theories of Psychiatric Genetics"

by Neuroskeptic in Neuroskeptic_Discover

Back in 2015, I ran a three part post (1,2,3) on Dr Kenneth Blum and his claim to be able to treat what he calls "Reward Deficiency Syndrome" (RDS) with nutritional supplements.

Today my interest was drawn to a 2015 paper from Blum and colleagues, called Neuroquantum Theories of Psychiatric Genetics: Can Physical Forces Induce Epigenetic Influence on Future Genomes?.



In this paper, Blum et al. put forward some novel proposals about possible links between physics, epigenetics, and neuro... Read more »

  • March 14, 2017
  • 08:05 AM
  • 323 views

Solar Science with the Atacama Large Millimeter/Submillimeter Array — A New View of Our Sun by S. Wedemeyer

by CESRA in Solar Radio Science

The Atacama Large Millimeter/submillimeter Array (ALMA), which consists of 66 antennas placed on the Chajnantor plateau in the Chilean Andes, has already produced impressive results for a large range of astronomical objects. Regular observations of the Sun have been carried out for the first time in December 2016 and exciting results can be expected soon. ALMA combines high spatial, temporal, and spectral resolution with the diagnostic advantages of radiation at [...]... Read more »

Wedemeyer, S., Bastian, T., Brajša, R., Hudson, H., Fleishman, G., Loukitcheva, M., Fleck, B., Kontar, E., De Pontieu, B., Yagoubov, P.... (2015) Solar Science with the Atacama Large Millimeter/Submillimeter Array—A New View of Our Sun. Space Science Reviews, 200(1-4), 1-73. DOI: 10.1007/s11214-015-0229-9  

  • March 14, 2017
  • 07:08 AM
  • 110 views

Nonlinear effects in shallow water waves

by Mirjam Sophia Glessmer in Adventures in Oceanography and Teaching

I recently googled for something related to the shape of waves and came across a photo of a wave that caught my eye, and it took me to a journey that lead to the article “nonlinear shallow ocean wave soliton interactions on flat beaches” by Ablowitz and Baldwin (2012). What’s discussed in that article is that while…... Read more »

Mark J. Ablowitz, & Douglas E. Baldwin. (2012) Nonlinear shallow ocean wave soliton interactions on flat beaches. Physical Review E, vol. 86(3), pp. 036305 (2012). arXiv: 1208.2904v1

  • February 28, 2017
  • 07:03 AM
  • 272 views

Quasi-periodic acceleration of electrons in the flare on 2012 July 19 by Jing Huang et al.*

by CESRA in Solar Radio Science

We study the quasi-periodic pulsations (QPPs) of nonthermal emission in an M7.7 class flare on 2012 July 19 with spatially resolved observations at microwave and HXR bands and with spectral observations at decimetric, metric waves. Microwave emission at 17 GHz of two footpoints, HXR emission at 20–50 keV of the north footpoint and loop top, and type III bursts at 0.7–3 GHz show prominent in-phase oscillations at 270$\,$s. Through the [...]... Read more »

Huang, J., Kontar, E., Nakariakov, V., & Gao, G. (2016) QUASI-PERIODIC ACCELERATION OF ELECTRONS IN THE FLARE ON 2012 JULY 19. The Astrophysical Journal, 831(2), 119. DOI: 10.3847/0004-637X/831/2/119  

  • February 24, 2017
  • 11:06 AM
  • 359 views

What if black holes were not... holes? A Los Alamos physicist explains his alternative theory behind these mysterious objects.

by EE Giorgi in CHIMERAS

© Elena E. GiorgiThe concept of a “black hole” — a celestial body so dense and massive that not even light can escape its gravitational field — dates back to the 18th century, with the theoretical work of Pierre-Simon Laplace and John Michell. But it wasn’t until the early 20th century that these mysterious dark objects were first described mathematically by German physicist Karl Schwarzschild. Schwarzschild’s work predicted the existence of a finite distance around the black hole (called the “event horizon”) from which light cannot escape. Emil Mottola, a physicist in the Theoretical Division at Los Alamos National Laboratory, laughs as he explains this bit of history behind black holes. “Would black holes have captured the popular imagination if they were still known as Schwarzschild’s solution?” he quips. Mottola has a point. The name “black hole” was coined by the American physicist John Wheeler in the 1960s, when these objects became the subject of serious study and first entered the popular vocabulary.“And then of course, Stephen Hawking made black holes very popular with his own research and theory of black hole radiation,” Mottola adds. “To this day,” he explains, “black holes are far from being understood, and science fiction may have taken over from science fact. We can’t answer many of the most important questions without knowing what the internal states of a black hole are, but no one has ever been inside a black hole, so no one actually knows what is inside.”One particularly vexing feature of black holes is the so-called “information paradox.” In 1974, Stephen Hawking theorized that black holes emit small amounts of radiation (called Hawking radiation). However, if this is true, black holes should eventually evaporate due to the loss of mass, leaving no way—not even in principle—to recover the information that was originally enclosed in it. This question alone has generated hundreds of research papers with still no completely satisfactory resolution. In 2001, Mottola and his colleague Pawel O. Mazur proposed an alternative to Hawking’s black hole theory that eliminates the paradox. “Think of a black hole as having a physical surface,” Mottola says. He imagines this surface to be much like a soap bubble that bends and fluctuates in space. “Our idea is that quantum effects build up right at the event horizon (the bubble’s surface), leading to a phase transition. This in turn creates a gravitational repulsive force inside the “bubble” that prevents the surface from collapsing. This repulsive force is the same ‘dark energy’ force believed to cause the expansion of the universe. We call these objects Gravitational Condensate Stars or ‘Gravastars’— celestial objects that would be compact, cold and dark, and look to astrophysicists just like ‘black holes,’ although they are not ‘holes’ at all. Our hypothesis does not contradict the conservation of information because there is no infinite crushing of space and time inside a Gravastar, and information is never destroyed.”According to Mottola, the mathematical equations Hawking used to describe the temperature of a black hole are in reality describing the surface tension of a Gravastar. “If we assume that black holes have a temperature, then they need to have an enormous entropy too, but we can’t easily explain that enormous black hole entropy. In our theory, black holes don’t have a temperature, they have surface tension, like soap bubbles. In 2015 we showed that this possibility of a surface and surface tension was already inherent in Schwarzschild’s original formulation of black hole interiors in 1916, and so is consistent with both Einstein’s General Relativity and Quantum Mechanics.”As I look over my notes, I pose Dr. Mottola one final question: “Is there any way to find out who’s right, you or Stephen Hawking?”He smiles because he knows that whatever Hawking says these days carries a lot of weight, including when he proposes that black holes could be mysterious portals to other universes. “I believe we may well find out the answer in the next five to ten years,” Mottola says. “If ‘black holes’ actually are Gravastars with a surface, their surface oscillations would cause them to emit gravitational waves at certain frequencies, which is a substantially different signal than that expected from the black holes that Hawking and colleagues theorize. LIGO directly detected gravitational waves for the first time in 2015, so we have just entered a new era of gravitational wave astronomy. In a few years, we may have enough data from the gravitational waves detected by LIGO and its sister observatories to be able to resolve the conundrum.”Needless to say, the Los Alamos scientist is very excited at that prospect. References[1] Mazur, P., & Mottola, E. (2004). Gravitational vacuum condensate stars Proceedings of the National Academy of Sciences, 101 (26), 9545-9550 DOI: 10.1073/pnas.0402717101[2] Emil Mottola (2010). New Horizons in Gravity: The Trace Anomaly, Dark Energy and CondensateStars Acta Physica Polonica B (2010) Vol.41, iss.9, p.2031-2162 arXiv: 1008.5006v1[3] Mazur, P., & Mottola, E. (2015). Surface tension and negative pressure interior of a non-singular ‘black hole’ Classical and Quantum Gravity, 32 (21) DOI: 10.1088/0264-9381/32/21/215024... Read more »

Mazur, P., & Mottola, E. (2004) Gravitational vacuum condensate stars. Proceedings of the National Academy of Sciences, 101(26), 9545-9550. DOI: 10.1073/pnas.0402717101  

Emil Mottola. (2010) New Horizons in Gravity: The Trace Anomaly, Dark Energy and Condensate Stars. Acta Physica Polonica B (2010) Vol.41, iss.9, p.2031-2162. arXiv: 1008.5006v1

  • February 20, 2017
  • 02:30 PM
  • 218 views

This Squid Gives Better Side-Eye Than You

by Elizabeth Preston in Inkfish



Yes, this cephalopod is looking at you funny. It's a kind of cockeyed squid—an animal that looks like some jokester misassembled a Mr. Potato Head. One of the cockeyed squid's eyes is big, bulging and yellow. The other is flat and beady. After studying more than 25 years' worth of undersea video footage, scientists think they know why.

The Monterey Bay Aquarium Research Institute (MBARI) in California has been dropping robotic submarines into the ocean for decades. The footage from those ... Read more »

  • February 14, 2017
  • 07:02 AM
  • 429 views

Large-scale simulations of Langmuir Wave Distributions Induced by Electron Beams by H. Reid and E. Kontar

by CESRA in Solar Radio Science

Langmuir waves that generate type III radio bursts are excited by high-energy electron beams streaming out from the corona through interplanetary space. Despite a smooth temporal distribution of electrons, the Langmuir waves are measured to occur in discrete clumps, commonly attributed to the turbulent nature of the solar wind electron density (e.g. Smith and Sime 1979, Melrose et al 1986). But how do fluctuations in the background plasma shape the [...]... Read more »

  • January 31, 2017
  • 07:06 AM
  • 632 views

Emission of radiation by plasmas with counter-streaming electron beams by L. F. Ziebell et al.*

by CESRA in Solar Radio Science

The phenomena of emission of radiation by the Sun, which are known as type II and type III solar radio bursts, have been known and investigated for more than sixty years. The bursts of radiation occur at a frequency corresponding to the plasma frequency at the source region, and harmonics [...]... Read more »

Ziebell, L., Petruzzellis, L., Yoon, P., Gaelzer, R., & Pavan, J. (2016) PLASMA EMISSION BY COUNTER-STREAMING ELECTRON BEAMS. The Astrophysical Journal, 818(1), 61. DOI: 10.3847/0004-637X/818/1/61  

  • January 17, 2017
  • 07:03 AM
  • 432 views

Simultaneous near-Sun observations of a moving type IV radio burst and the associated white-light CME by K. Hariharan et al.*

by CESRA in Solar Radio Science

Quasi-continuum radio emissions of duration ~10-60 min that occur along with flares and coronal mass ejections (CMEs) in the solar atmosphere are termed as type IV bursts. The bursts are non-thermal in nature and can be classified into two categories, i.e. moving type IV (type IVm) bursts and stationary type [...]... Read more »

  • January 3, 2017
  • 07:01 AM
  • 448 views

Observation of quasi-periodic solar radio bursts associated with propagating fast-mode waves by C. R. Goddard et al.*

by CESRA in Solar Radio Science

Flaring activity on the Sun triggers waves and oscillations in the solar corona. The study of these waves and oscillations allows comparisons to magnetohydrodynamic (MHD) theory and modelling to be made, and seismological inversions based on this comparison allow local plasma parameters to be measured indirectly (e.g. De Moortel & [...]... Read more »

  • December 30, 2016
  • 12:20 PM
  • 446 views

Yang-Mills theory paper gets published!

by Marco Frasca in The Gauge Connection

Exact solutions of quantum field theories are very rare and, normally, refer to toy models and pathological cases. Quite recently, I put on arxiv a pair of papers presenting exact solutions both of the Higgs sector of the Standard Model and the Yang-Mills theory made just of gluons. The former appeared a few month ago […]... Read more »

Marco Frasca. (2015) A theorem on the Higgs sector of the Standard Model. Eur. Phys. J. Plus (2016) 131: 199. arXiv: 1504.02299v3

Marco Frasca. (2015) Quantum Yang-Mills field theory. arXiv. arXiv: 1509.05292v1

Carl M. Bender, Kimball A. Milton, & Van M. Savage. (1999) Solution of Schwinger-Dyson Equations for ${\cal PT}$-Symmetric Quantum Field Theory. Phys.Rev.D62:085001,2000. arXiv: hep-th/9907045v1

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