#TXS 0506+056

[astroblogs]

IceCube heeft hoogenergetische neutrino's waargenomen uit M77 (NGC 1068)

IceCube heeft hoogenergetische neutrino’s waargenomen uit M77 (NGC 1068)

IceCube. Credit: MARTIN WOLF, ICECUBE/NSF Een internationaal team van wetenschappers heeft met behulp van de IceCube detector in het ijs van de Zuidpool hoogenergetische neutrino’s ontdekt die afkomstig zijn uit M77 (NGC 1068), het bekende actieve sterrenstelsel in het sterrenbeeld Walvis (Cetus), 47 miljoen lichtjaar van ons vandaan. Het is de tweede keer dat met IceCube de bron van…

[adrianusv61]

IceCube heeft hoogenergetische neutrino's waargenomen uit M77 (NGC 1068)

IceCube heeft hoogenergetische neutrino’s waargenomen uit M77 (NGC 1068)

IceCube. Credit: MARTIN WOLF, ICECUBE/NSF Een internationaal team van wetenschappers heeft met behulp van de IceCube detector in het ijs van de Zuidpool hoogenergetische neutrino’s ontdekt die afkomstig zijn uit M77 (NGC 1068), het bekende actieve sterrenstelsel in het sterrenbeeld Walvis (Cetus), 47 miljoen lichtjaar van ons vandaan. Het is de tweede keer dat met IceCube de bron van…

[sciencespies]

Neutrinos have been spotted coming from a strange, shrouded galaxy

https://sciencespies.com/space/neutrinos-have-been-spotted-coming-from-a-strange-shrouded-galaxy/

Neutrinos have been spotted coming from a strange, shrouded galaxy

Cosmic neutrinos are tough to track – it has only been done once before – but researchers from the IceCube observatory in Antarctica have tracked 79 of them back to their home galaxy

Space 3 November 2022

By Leah Crane

The IceCube Lab has traced neutrinos back to their home galaxy

Martin Wolf, IceCube/NSF

The IceCube Neutrino Observatory in Antarctica has found a second source for high-energy neutrinos from outer space. These particles are notoriously hard to spot and even harder to trace back to their sources, but they perfuse the entire universe. This finding helps give a better understanding of where they form.

The IceCube researchers, led by Francis Halzen at the University of Wisconsin-Madison, found their first definitive source for a single high-energy cosmic neutrino in 2017: a blazar called TXS 0506+056 blasting a huge jet of energy towards Earth. That finding was made with the help of many other telescopes, but by using an updated method to analyse nearly a decade’s worth of data the team was able to find its second neutrino source, called NGC 1068, without any outside help.

The researchers traced 79 high-energy neutrinos back to this relatively nearby galaxy. “When we first published these 10 years of data, NCG 1068 was there, but we were not sure if it was a background fluctuation or if it was a real source,” says Halzen. “Now we know these are not fluctuations.”

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Cosmic neutrinos are produced when a proton slams into another particle, creating a shower of fundamental particles, some of which later decay and release neutrinos. NGC 1068 seems like a near-perfect environment for this to happen. It is an active galaxy, meaning its central supermassive black hole is gobbling up material and creating powerful radiation as it does so. But its centre is shrouded in a dense knot of gas and dust, which obscures the black hole while giving the radiation something to slam into in order to produce neutrinos.

There are far more active galaxies like this one than blazars similar to TXS 0506+056, so this finding might help explain why there are so many cosmic neutrinos floating around the universe. “The diffuse [flow of neutrinos] we see from the universe is around 100 times larger than what we get from this one source, so there is still room for surprises, but if I were going to bet my wallet it would be on this kind of object,” says Halzen.

The researchers are now working on further refining their analytical methods and upgrading the detector so that we can track more neutrinos and gain a better understanding of how they are made.

Journal reference: Science, DOI: 10.1126/science.abg3395

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#Space

[astroimages]

ASTRÔNOMOS DETECTAM PARTÍCULAS FANTASMAS VINDAS DE GALÁXIA ATIVA!!!

ASSINE AGORA O SPACE TODAY PLUS, R29,90 POR MÊS, MENOS DE 1 REAL POR DIA, PARA VOCÊ ACOMPANHAR, SÉRIES, DOCUMENTÁRIOS, CONTEÚDOS EXCLUSIVOS!!! https://quero.plus Pela primeira vez, uma equipe internacional de cientistas encontrou evidências de emissão de neutrinos de alta energia da NGC 1068, também conhecida como Messier 77, uma galáxia ativa na constelação de Cetus e uma das galáxias mais conhecidas e bem estudadas até hoje. Avistada pela primeira vez em 1780, esta galáxia, localizada a 47 milhões de anos-luz de nós, pode ser observada com grandes binóculos. Os resultados, a serem publicados amanhã (4 de novembro de 2022) na Science , foram compartilhados hoje em um webinar científico online que reuniu especialistas, jornalistas e cientistas de todo o mundo. A detecção foi feita no Observatório de Neutrino IceCube, apoiado pela National Science Foundation, um enorme telescópio de neutrinos que abrange 1 bilhão de toneladas de gelo instrumentado em profundidades de 1,5 a 2,5 quilômetros abaixo da superfície da Antártida, perto do Pólo Sul. Este telescópio único, que explora os confins do nosso universo usando neutrinos, relatou a primeira observação de uma fonte de neutrinos astrofísicos de alta energia em 2018. A fonte, TXS 0506+056, é um blazar conhecido localizado no ombro esquerdo do Orion constelação e a 4 bilhões de anos-luz de distância. “Um neutrino pode destacar uma fonte. Mas apenas uma observação com vários neutrinos revelará o núcleo obscuro dos objetos cósmicos mais energéticos”, diz Francis Halzen, professor de física da Universidade de Wisconsin-Madison e investigador principal do IceCube. Ele acrescenta: “O IceCube acumulou cerca de 80 neutrinos de energia teraelectronvolt do NGC 1068, que ainda não são suficientes para responder a todas as nossas perguntas, mas definitivamente são o próximo grande passo para a realização da astronomia de neutrinos”. Ao contrário da luz, os neutrinos podem escapar em grande número de ambientes extremamente densos no universo e chegar à Terra em grande parte não perturbados pela matéria e pelos campos eletromagnéticos que permeiam o espaço extragaláctico. Embora os cientistas tenham imaginado a astronomia de neutrinos há mais de 60 anos, a fraca interação dos neutrinos com a matéria e a radiação torna sua detecção extremamente difícil. Neutrinos podem ser a chave para nossas perguntas sobre o funcionamento dos objetos mais extremos do cosmos. “Responder a essas perguntas de longo alcance sobre o universo em que vivemos é o foco principal da US National Science Foundation”, diz Denise Caldwell, diretora da Divisão de Física da NSF. Como é o caso da nossa galáxia, a Via Láctea, NGC 1068 é uma galáxia espiral barrada, com braços frouxamente enrolados e uma protuberância central relativamente pequena. No entanto, ao contrário da Via Láctea, NGC 1068 é uma galáxia ativa onde a maior parte da radiação não é produzida por estrelas, mas devido ao material cair em um buraco negro milhões de vezes mais massivo que o nosso Sol e ainda mais massivo que o buraco negro inativo no centro da nossa galáxia. NGC 1068 é uma galáxia ativa – um tipo Seyfert II em particular – vista da Terra em um ângulo que obscurece sua região central onde o buraco negro está localizado. Em uma galáxia Seyfert II, um toro de poeira nuclear obscurece a maior parte da radiação de alta energia produzida pela densa massa de gás e partículas que espiralam lentamente em direção ao centro da galáxia. Com as medições de neutrinos de TXS 0506+056 e NGC 1068, o IceCube está um passo mais perto de responder à questão centenária da origem dos raios cósmicos. Além disso, esses resultados implicam que pode haver muito mais objetos semelhantes no universo ainda a serem identificados. “A revelação do universo obscuro acabou de começar, e os neutrinos estão prontos para liderar uma nova era de descobertas na astronomia”, diz Elisa Resconi, professora de física da TUM e outra analisadora principal. FONTE: https://icecube.wisc.edu/news/press-releases/2022/11/icecube-neutrinos-give-us-first-glimpse-into-the-inner-depths-of-an-active-galaxy/ https://www.science.org/doi/epdf/10.1126/science.abg3395 #NEUTRINOS #ICECUBE #ACTIVEGALAXY

[just--space]

Neutrino Associated with Distant Blazar Jet : With equipment frozen deep into ice beneath Earth's South Pole, humanity appears to have discovered a neutrino from far across the universe. If confirmed, this would mark the first clear detection of cosmologically-distant neutrinos and the dawn of an observed association between energetic neutrinos and cosmic rays created by powerful jets emanating from blazing quasars (blazars). Once the Antarctican IceCube detector measured an energetic neutrino in 2017 September, many of humanity's premier observatories sprang into action to try to identify a counterpart in light. And they did. An erupting counterpart was pinpointed by high energy observatories including AGILE, Fermi, HAWC, H.E.S.S., INTEGRAL, NuSTAR, Swift, and VERITAS, which found that gamma-ray blazar TXS 0506+056 was in the right direction and with gamma-rays from a flare arriving nearly coincidental in time with the neutrino. Even though this and other position and time coincidences are statistically strong, astronomers will await other similar neutrino - blazar light associations to be absolutely sure. Pictured here is an artist's drawing of a particle jet emanating from a black hole at the center of a blazar. via NASA

[spaceexp]

Neutrino produced in a cosmic collider far away

Bonn, Germany (SPX) Oct 03, 2019 The neutrino event IceCube 170922A, detected at the IceCube Neutrino Observatory at the South Pole, appears to originate from the distant active galaxy TXS 0506+056, at a light travel distance of 3.8 billion light-years. TXS 0506+056 is one of many active galaxies and it remained a mystery, why and how only this particular galaxy generated neutrinos so far. An international team of researc Full article

[nasa]

Using All of Our Senses in Space

Today, we and the National Science Foundation (NSF) announced the detection of light and a high-energy cosmic particle that both came from near a black hole billions of trillions of miles from Earth. This discovery is a big step forward in the field of multimessenger astronomy.

But wait — what is multimessenger astronomy? And why is it a big deal?

People learn about different objects through their senses: sight, touch, taste, hearing and smell. Similarly, multimessenger astronomy allows us to study the same astronomical object or event through a variety of “messengers,” which include light of all wavelengths, cosmic ray particles, gravitational waves, and neutrinos — speedy tiny particles that weigh almost nothing and rarely interact with anything. By receiving and combining different pieces of information from these different messengers, we can learn much more about these objects and events than we would from just one.

Lights, Detector, Action!  

Much of what we know about the universe comes just from different wavelengths of light. We study the rotations of galaxies through radio waves and visible light, investigate the eating habits of black holes through X-rays and gamma rays, and peer into dusty star-forming regions through infrared light.

The Fermi Gamma-ray Space Telescope, which recently turned 10, studies the universe by detecting gamma rays — the highest-energy form of light. This allows us to investigate some of the most extreme objects in the universe.

Last fall, Fermi was involved in another multimessenger finding — the very first detection of light and gravitational waves from the same source, two merging neutron stars. In that instance, light and gravitational waves were the messengers that gave us a better understanding of the neutron stars and their explosive merger into a black hole.

Fermi has also advanced our understanding of blazars, which are galaxies with supermassive black holes at their centers. Black holes are famous for drawing material into them. But with blazars, some material near the black hole shoots outward in a pair of fast-moving jets. With blazars, one of those jets points directly at us!

Multimessenger Astronomy is Cool

Today’s announcement combines another pair of messengers. The IceCube Neutrino Observatory lies a mile under the ice in Antarctica and uses the ice itself to detect neutrinos. When IceCube caught a super-high-energy neutrino and traced its origin to a specific area of the sky, they alerted the astronomical community.

Fermi completes a scan of the entire sky about every three hours, monitoring thousands of blazars among all the bright gamma-ray sources it sees. For months it had observed a blazar producing more gamma rays than usual. Flaring is a common characteristic in blazars, so this did not attract special attention. But when the alert from IceCube came through about a neutrino coming from that same patch of sky, and the Fermi data were analyzed, this flare became a big deal!

IceCube, Fermi, and followup observations all link this neutrino to a blazar called TXS 0506+056. This event connects a neutrino to a supermassive black hole for the very first time.  

Why is this such a big deal? And why haven’t we done it before? Detecting a neutrino is hard since it doesn’t interact easily with matter and can travel unaffected great distances through the universe. Neutrinos are passing through you right now and you can’t even feel a thing!

The neat thing about this discovery — and multimessenger astronomy in general — is how much more we can learn by combining observations. This blazar/neutrino connection, for example, tells us that it was protons being accelerated by the blazar’s jet. Our study of blazars, neutrinos, and other objects and events in the universe will continue with many more exciting multimessenger discoveries to come in the future.

Want to know more? Read the story HERE.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com

[thetimeandspaceblog]

Neutrino Associated with Distant Blazar Jet With equipment frozen deep into ice beneath Earth's South Pole, humanity appears to have discovered a neutrino from far across the universe. If confirmed, this would mark the first clear detection of cosmologically-distant neutrinos and the dawn of an observed association between energetic neutrinos andcosmic rays created by powerful jets emanating from blazing quasars (blazars). Once the Antarctican IceCube detector measured an energetic neutrino in 2017 September, many of humanity's premier observatories sprang into action to try to identify a counterpart in light. And they did. An erupting counterpart was pinpointed by high energy observatories including AGILE,Fermi, HAWC, H.E.S.S., INTEGRAL, NuSTAR,Swift, and VERITAS, which found that gamma-ray blazar TXS 0506+056 was in the right direction and with gamma-rays from aflare arriving nearly coincidental in time with the neutrino. Even though this and otherposition and time coincidences are statistically strong, astronomers will await other similar neutrino - blazar light associations to be absolutely sure. Pictured here is an artist's drawing of a particle jetemanating from a black hole at the center of a blazar. For image credit and copyright guidance, please visit the image websitehttps://apod.nasa.gov/apod/ap180716.html Fermi Time And Space

[startswithabang]

A Cosmic First: Ultra-High Energy Neutrinos Found, From Blazing Galaxies Across The Universe

“A new scientific field, that of high-energy neutrino astronomy, officially launches with this discovery. Neutrinos are no longer a by-product of other interactions, nor a cosmic curiosity that barely extends beyond our Solar System. Instead, we can use them as a fundamental probe of the Universe and of the basic laws of physics itself. One of the major goals in building IceCube was to identify the sources of high-energy cosmic neutrinos. With the identification of the blazar TXS 0506+056 as the source for both these neutrinos and of gamma rays, that's one cosmic dream that's at last been achieved.”

From all over the Universe, cosmic particles zip around, occasionally colliding with Earth. These high-energy cosmic rays collide with our atmosphere, and we see the results in a cascading shower of particles. At the same time, we’ve detected ultra-high-energy neutrinos at observatories like IceCube, which originate not in our atmosphere, but from the distant astrophysical source where they were produced. At long last, we’ve matched up these two signals and found a location for them: an ultra-distant blazar some 4 billion light years away. From our perspective, with a quasar jet pointed right at us, it’s one of the brightest objects in the Universe. And now, for the first time, we know at least one place where these particles originate.

It’s an incredible cosmic first, and you won’t want to miss all the details on how we found these high-energy neutrinos and what it means for our Universe!

[astroblogs]

Fermi en IceCube zien fotonen en neutrino's vanuit één bron - een blazar met een superzwaar zwart gat

Fermi en IceCube zien fotonen en neutrino’s vanuit één bron – een blazar met een superzwaar zwart gat

Voorstelling van de detectie van fotonen en neutrino’s door Fermi (boven) en IceCube (beneden).

Vandaag is zoals aangekondigdop een perconferentie van de NSF bekendgemaakt dat sterrenkundigen erin geslaagd zijn om vanuit één bron aan de hemel, de ‘blazar’ genaamd TXS 0506+056 – een sterrenstelsel in het sterrenbeeld Orion op 3,7 miljard lichtjaar afstand met een superzwaar zwart gat, wiens…

[4gravitons]

The Physics Isn't New, We Are

The Physics Isn’t New, We Are

Last week, I mentioned the announcement from the IceCube, Fermi-LAT, and MAGIC collaborations of high-energy neutrinos and gamma rays detected from the same source, the blazar TXS 0506+056. Blazars are sources of gamma rays, thought to be enormous spinning black holes that act like particle colliders vastly more powerful than the LHC. This one, near Orion’s elbow, is “aimed” roughly at Earth,…

[kerbaldevteam]

KSP Weekly: The Ghost Particle

Welcome to KSP Weekly! Yesterday, scientists at the US National Science Foundation (NSF) made an announcement to reveal exciting findings from its IceCube observatory at the South Pole. IceCube – opened in 2010 – is designed to detect neutrinos from elsewhere in the cosmos that make their way to Earth. It uses 86 strings of detectors stretching 2.5 kilometers (1.6 miles) below the Antarctic ice to hunt for these particles. If a neutrino strikes an atom in the ice, it explodes in a shower of secondary particles, detected by the observatory, which then works out where the neutrino came from. Now for first time ever, an international team of astronomers has found the origin of some of these high-energy particles coming from the distant universe!

A neutrino is a fundamental subatomic particle just as tiny as an electron, but without any charge. Scientists know neutrinos have a tiny bit of mass, but they can't pin down exactly how little, because neutrinos don't interact with their surroundings very often, which makes them difficult for scientists to spot. However, on September 22, 2017, the IceCube observatory detected an incoming high-energy neutrino. This advanced detector has a real-time alert system, and broadcasted the coordinates of the detection to astronomers around the world just 43 seconds after its discovery.

About 20 observatories including NASA's orbiting Fermi Gamma-ray Space Telescope responded to the alert, and trained their views on the skies to try to work out where it was coming from. The process was possible because neutrinos, like photons of light, can cross extremely large distances in the universe in straight lines, without being pulled off course. Other types of high-energy particles can't do that because they are charged. The combined observations traced the neutrino's origin to an already-known blazar called TXS 0506+056, which lies about 4 billion light-years from Earth. Blazars are active galactic nuclei with a relativistic jet (a jet traveling at nearly the speed of light), in which the jet is directed very nearly toward the Earth, emitting gamma rays along other particles.

Physicists hope that by studying these particles, they can find clues about some of the biggest mysteries in the cosmos. One of those cosmic mysteries could include an explanation for dark matter. Dark matter has a gravitational pull on regular matter, and it has shaped the cosmic landscape throughout the history of the universe. Some theorists think dark matter could even be a new type of neutrino. We are now in an exciting new era of astronomy where we can study objects not just in electromagnetic radiation, but in the other particles they emit too. Incredible!

[Development news start here]

With an upcoming 1.4.5 patch about to come out of the oven, this week had the team performing various polish-related tasks. The QA team was particularly busy, testing and pushing to the limits all the fixes performed by the devs last week.

Meanwhile, the devs had also their good share of work. For instance, the version checking system has been fully established. This versioning system will trigger a warning dialog whenever there’s a problem with a save, craft or mission file due to incompatibility. Users will be able to load their files anyways, but at their own risk of course.

The work on KSP Enhanced Edition is also at a similar stage. BlitWorks has been performing a great deal of bug fixes, improvements, and feedback-based additions for an upcoming patch for the console versions of KSP, and we’re getting really close to its launch. So stay tuned to learn more about the patch and its official release date!

Remember that you can also share and download missions on Curse, KerbalX, and the KSP Forum.

That’s it for this week. Be sure to join us on our official forums, and don’t forget to follow us on Twitter and Facebook. Stay tuned for more exciting and upcoming news and development updates!

Happy launchings!

*Information Source:

Collaboration, I. (2018, July 13). Neutrino emission from the direction of the blazar TXS 0506 056 prior to the IceCube-170922A alert. Retrieved from http://science.sciencemag.org/content/361/6398/147

HAWC, Liverpool Telescope, Subaru, & VERITAS. (2018, July 13). Multimessenger observations of a flaring blazar coincident with high-energy neutrino IceCube-170922A. Retrieved from http://science.sciencemag.org/content/361/6398/eaat1378

O`Callaghan, J. (2018, July 12). Incredible 'Ghost Particle' Discovery Heralds A New Era In Astronomy. Retrieved from http://www.iflscience.com/space/incredible-ghost-particle-discovery-heralds-a-new-era-in-astronomy/

Bartels, M. (2018, July 12). Here's Why IceCube's Neutrino Discovery Is a Big Deal. Retrieved from https://www.space.com/41142-what-are-neutrinos-why-they-matter.html

Wall, M. (2018, July 12). High-Energy 'Ghost Particle' Traced to Distant Galaxy in Astronomy Breakthrough. Retrieved from https://www.space.com/41146-neutrino-source-blazar-cosmic-rays.html 

[space-news]

NASA’s Fermi Traces Source of Cosmic Neutrino to Monster Black Hole

For the first time ever, scientists using NASA’s Fermi Gamma-ray Space Telescope have found the source of a high-energy neutrino from outside our galaxy. This neutrino traveled 3.7 billion years at almost the speed of light before being detected on Earth. This is farther than any other neutrino whose origin scientists can identify.

High-energy neutrinos are hard-to-catch particles that scientists think are created by the most powerful events in the cosmos, such as galaxy mergers and material falling onto supermassive black holes. They travel at speeds just shy of the speed of light and rarely interact with other matter, allowing them to travel unimpeded across distances of billions of light-years.

The discovery of a high-energy neutrino on September 22, 2017, sent astronomers on a chase to locate its source—a supermassive black hole in a distant galaxy.Credits: NASA’s Goddard Space Flight Center

Video: NASA's Fermi Links Cosmic Neutrino to Monster Black Hole

The neutrino was discovered by an international team of scientists using the National Science Foundation’s IceCube Neutrino Observatory at the Amundsen–Scott South Pole Station. Fermi found the source of the neutrino by tracing its path back to a blast of gamma-ray light from a distant supermassive black hole in the constellation Orion.

“Again, Fermi has helped make another giant leap in a growing field we call multimessenger astronomy,” said Paul Hertz, director of the Astrophysics Division at NASA Headquarters in Washington. “Neutrinos and gravitational waves deliver new kinds of information about the most extreme environments in the universe. But to best understand what they’re telling us, we need to connect them to the ‘messenger’ astronomers know best—light.”

Scientists study neutrinos, as well as cosmic rays and gamma rays, to understand what is going on in turbulent cosmic environments such as supernovas, black holes and stars. Neutrinos show the complex processes that occur inside the environment, and cosmic rays show the force and speed of violent activity. But, scientists rely on gamma rays, the most energetic form of light, to brightly flag what cosmic source is producing these neutrinos and cosmic rays.

“The most extreme cosmic explosions produce gravitational waves, and the most extreme cosmic accelerators produce high-energy neutrinos and cosmic rays,” says Regina Caputo of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, the analysis coordinator for the Fermi Large Area Telescope Collaboration. “Through Fermi, gamma rays are providing a bridge to each of these new cosmic signals.”

The discovery is the subject of two papers published Thursday in the journal Science. The source identification paper also includes important follow-up observations by the Major Atmospheric Gamma Imaging Cherenkov Telescopes and additional data from NASA’s Neil Gehrels Swift Observatory and many other facilities.

Fermi-detected gamma rays from TXS 0506+056 are shown as expanding circles. Their maximum size, color—from white (low) to magenta (high)—and associated tone indicate the energy of each ray. The first sequence shows typical emission; the second shows the 2017 flare leading to the neutrino detection.Credits: NASA/DOE/Fermi LAT Collab., Matt Russo and Andrew Santaguida/SYSTEM Sounds

Video: Visualizing Gamma Rays From Blazar TXS 0506+056

On Sept. 22, 2017, scientists using IceCube detected signs of a neutrino striking the Antarctic ice with energy of about 300 trillion electron volts—more than 45 times the energy achievable in the most powerful particle accelerator on Earth. This high energy strongly suggested that the neutrino had to be from beyond our solar system. Backtracking the path through IceCube indicated where in the sky the neutrino came from, and automated alerts notified astronomers around the globe to search this region for flares or outbursts that could be associated with the event.

Data from Fermi’s Large Area Telescope revealed enhanced gamma-ray emission from a well-known active galaxy at the time the neutrino arrived. This is a type of active galaxy called a blazar, with a supermassive black hole with millions to billions of times the Sun’s mass that blasts jets of particles outward in opposite directions at nearly the speed of light. Blazars are especially bright and active because one of these jets happens to point almost directly toward Earth.

Fermi scientist Yasuyuki Tanaka at Hiroshima University in Japan was the first to associate the neutrino event with the blazar designated TXS 0506+056 (TXS 0506 for short).

“Fermi’s LAT monitors the entire sky in gamma rays and keeps tabs on the activity of some 2,000 blazars, yet TXS 0506 really stood out,” said Sara Buson, a NASA Postdoctoral Fellow at Goddard who performed the data analysis with Anna Franckowiak, a scientist at the Deutsches Elektronen-Synchrotron research center in Zeuthen, Germany. “This blazar is located near the center of the sky position determined by IceCube and, at the time of the neutrino detection, was the most active Fermi had seen it in a decade.”

NASA's Fermi Gamma-ray Space Telescope is an astrophysics and particle physics partnership, developed in collaboration with the U.S. Department of Energy and with important contributions from academic institutions and partners in France, Germany, Italy, Japan, Sweden and the United States. The NASA Postdoctoral Fellow program is administered by Universities Space Research Association under contract with NASA.

[arxt1]

Testing High-Energy Emission Models for Blazars with X-ray Polarimetry. (arXiv:2204.11803v1 [astro-ph.HE])

Both leptonic and hadronic emission processes may contribute to blazar jet emission; which dominates in blazars's high energy emission component remains an open question. Some intermediate synchrotron peaked blazars transition from their low to high energy emission components in the X-ray band making them excellent laboratories to probe both components simultaneously, and good targets for the newly launched Imaging X-ray Polarimetry Explorer. We characterize the spectral energy distributions for three such blazars: CGRaBS~J0211+1051, TXS~0506+056, and S5~0716+714, predicting their X-ray polarization behavior by fitting a multizone polarized leptonic jet model. We find that a significant detection of electron synchrotron dominated polarization is possible with a 300~ks observation for S5~0716+714 and CGRaBS~J0211+1051 in their flaring states, while even 500~ks observations are unlikely to measure synchrotron self-Compton polarization. Importantly, non-leptonic emission processes like proton synchrotron are marginally detectable for our brightest ISP, S5~0716+714, during a flaring state. Improved {\it IXPE} data reduction methods or next generation telescopes like {\it eXTP} are needed to confidently measure SSC polarization.

from astro-ph.HE updates on arXiv.org https://ift.tt/34z0KeR

[spaceexp]

Multi-messenger astronomy

ESA - INTEGRAL Mission patch. 12 July 2018 An international team of scientists has found first evidence of a source of high-energy neutrinos: a flaring active galaxy, or blazar, 4 billion light years from Earth. Following a detection by the IceCube Neutrino Observatory on 22 September 2017, ESA's INTEGRAL satellite joined a collaboration of observatories in space and on the ground that kept an eye on the neutrino source, heralding the thrilling future of multi-messenger astronomy. Neutrinos are nearly massless, ‘ghostly’ particles that travel essentially unhindered through space at close to the speed of light [1]. Despite being some of the most abundant particles in the Universe – 100 000 billion pass through our bodies every second – these electrically neutral, subatomic particles are notoriously difficult to detect because they interact with matter incredibly rarely.

Image above: Artist's impression of blazar neutrinos and gamma rays reaching Earth. Image Credits: IceCube/NASA. While primordial neutrinos were created during the Big Bang, more of these elusive particles are routinely produced in nuclear reactions across the cosmos. The majority of neutrinos arriving at Earth derive from the Sun, but those that reach us with the highest energies are thought to stem from the same sources as cosmic rays – highly energetic particles originating from exotic sources outside the Solar System. Unlike neutrinos, cosmic rays are charged particles and so their path is bent by magnetic fields, even weak ones. The neutral charge of neutrinos instead means they are unaffected by magnetic fields, and because they pass almost entirely through matter they can be used to trace a straight path all the way back to their source. Acting as ‘messengers’, neutrinos directly carry astronomical information from the far reaches of the Universe. Over the past decades, several instruments have been built on Earth and in space to decode their messages, though detecting these particles is no easy feat. In particular, the source of high-energy neutrinos has, until now, remained unproven. On 22 September 2017, one of these high-energy neutrinos arrived at the IceCube Neutrino Observatory at the South Pole [2]. The event was named IceCube-170922A. The IceCube observatory, which encompasses a cubic kilometre of deep, pristine ice, detects neutrinos through their secondary particles, muons. These muons are produced on the rare occasion that a neutrino interacts with matter in the vicinity of the detector, and they create tracks, kilometres in length, as they pass through layers of Antarctic ice. Their long paths mean their position can be well defined, and the source of the parent neutrino can be pinned down in the sky. During the 22 September event, a traversing muon deposited 22 TeV of energy in the IceCube detector. From this, scientists estimated the energy of the parent neutrino to be around 290 TeV, indicating a 50 percent chance that it had an astrophysical origin beyond the Solar System.

Image above: Neutrino detection at the IceCube observatory. Image Credits: IceCube Collaboration/NSF. When the origin of a neutrino cannot be robustly identified by IceCube, like in this case, multi-wavelength observations are required to investigate its source. So, following the detection, IceCube scientists circulated the coordinates in the sky of the neutrino’s origin, inferred from their observations, to a worldwide network of ground and space-based observatories working across the full electromagnetic spectrum. These included NASA's Fermi gamma-ray space telescope and the Major Atmospheric Gamma-Ray Imaging Cherenkov (MAGIC) on La Palma, in the Canary Islands, which looked to this portion of the sky and found the known blazar, TXS 0506+056, in a ‘flaring’ state – a period of intense high-energy emission – at the same time the neutrino was detected at the South Pole. Blazars are the central cores of giant galaxies that host an actively accreting supermassive black-hole at their heart, where matter spiralling in forms a hot, rotating disc that generates enormous amounts of energy, along with a pair of relativistic jets. These jets are colossal columns that funnel radiation, photons and particles – including neutrinos and cosmic rays – tens of light years away from the central black hole at speeds very close to the speed of light. A specific feature of blazars is that one of these jets happens to point towards Earth, making its emission appear exceptionally bright. Scientists around the world began observing this blazar – the likely source of the neutrino detected by IceCube – in a variety of wavelengths, from radio waves to high-energy gamma rays. ESA's INTEGRAL gamma-ray observatory was part of this international collaboration [3]. “This is a very important milestone to understanding how high-energy neutrinos are produced,” says Carlo Ferrigno from the INTEGRAL Science Data Centre at the University of Geneva, Switzerland. “There have been previous claims that blazar flares were associated with the production of neutrinos, but this, the first confirmation, is absolutely fundamental. This is an exciting period for astrophysics,” he adds. INTEGRAL, which surveys the sky in hard X-rays and soft gamma rays, is also sensitive to transient high-energy sources across the whole sky. At the time the neutrino was detected, it did not record any burst of gamma rays from the location of the blazar, so scientists were able to rule out prompt emissions from certain sources, such as a gamma-ray burst.

Image above: Artist's impression of INTEGRAL. Image Credit: ESA. After the neutrino alert from IceCube, INTEGRAL pointed to this area of the sky on various occasions between 30 September and 24 October 2017 with its wide-field instruments, and it did not observe the blazar to be in a flaring state in the hard X-ray or soft gamma-ray range. The fact that INTEGRAL could not detect the source in the follow-up observations provided significant information about this blazar, allowing scientists to place a useful upper limit on its energy output during this period. “INTEGRAL was important in constraining the properties of this blazar, but also in allowing scientists to exclude other neutrino sources such as gamma-ray bursts,” explains Volodymyr Savchenko from the INTEGRAL Science Data Centre, who led the analysis of the INTEGRAL data. With facilities spread across the globe and in space, scientists now have the capability to detect a plethora of 'cosmic messengers' travelling vast distances at extremely high speeds, in the form of light, neutrinos, cosmic rays, and even gravitational waves. “The ability to globally marshal telescopes to make a discovery using a variety of wavelengths in cooperation with a neutrino detector like IceCube marks a milestone in what scientists call multi-messenger astronomy,” says Francis Halzen from the University of Wisconsin–Madison, USA, lead scientist for the IceCube Neutrino Observatory. By combining the information gathered by each of these sophisticated instruments to investigate a wide range of cosmic processes, the era of multi-messenger astronomy has truly entered the phase of scientific exploitation. ESA’s high-energy space telescopes are fully integrated into this network of large multi-messenger collaborations, as demonstrated during the recent detection of gravitational waves with a corresponding gamma-ray burst – the latter detected by INTEGRAL – released by the collision of two neutron stars, and in the subsequent follow-up campaign, with contributions by INTEGRAL as well as the XMM-Newton X-ray observatory. Pooling resources from these and other observatories is key for the future of astrophysics, fostering our ability to decode the messages that reach us from across the Universe. “INTEGRAL is the only observatory available in the hard X-ray and soft gamma-ray domain that has the ability to perform dedicated imaging and spectroscopy, as well as having an instantaneous all-sky view at any time,” notes Erik Kuulkers, INTEGRAL project scientist at ESA. “After more than 15 years of operations, INTEGRAL is still at the forefront of high-energy astrophysics.” Notes: [1] Described by Frederick Reines, one of the scientists who made the first neutrino detection, as “... the most tiny quantity of reality ever imagined by a human being,” one neutrino is estimated to contain one millionth of the mass of an electron. [2] The IceCube Collaboration is funded primarily by the National Science Foundation and is operated by a team headquartered at the University of Wisconsin–Madison, USA. The research efforts, including critical contributions to the detector operation, are supported by funding agencies in Australia, Belgium, Canada, Denmark, Germany, Japan, New Zealand, Republic of Korea, Sweden, Switzerland, the United Kingdom, and the USA. [3] These results are detailed in the paper “Multimessenger observations of a flaring blazar coincident with high-energy neutrino IceCube-170922A” by The IceCube, Fermi-LAT, MAGIC, AGILE, ASAS-SN, HAWC, H.E.S.S, INTEGRAL, Kanata, Kiso, Kapteyn, Liverpool telescope, Subaru, Swift/NuSTAR, VERITAS, and VLA/17B-403 teams, published in Science: http://science.sciencemag.org/cgi/doi/10.1126/science.aat1378 Related article: NASA’s Fermi Traces Source of Cosmic Neutrino to Monster Black Hole https://orbiterchspacenews.blogspot.com/2018/07/nasas-fermi-traces-source-of-cosmic.html ESA's INTEGRAL gamma-ray observatory: http://sci.esa.int/integral ESA's XMM-Newton X-ray observatory: http://sci.esa.int/xmm-newton/60376-cosmic-blast-takes-rest-at-last/ Images (mentioned), Text, Credits: ESA/Markus Bauer/Erik Kuulkers/INTEGRAL Science Data Centre/University of Geneva/Volodymyr Savchenko/Carlo Ferrigno/IceCube/University of Wisconsin–Madison/Francis Halzen/Sílvia Bravo Gallart. Greetings, Orbiter.ch Full article

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Le osservazioni svelano le proprietà del getto di un blazar che emette neutrini

Le osservazioni svelano le proprietà del getto di un blazar che emette neutrini

Utilizzando la tecnica dell’interferometria a lunghissima base (VLBI), gli astronomi hanno sondato il getto in scala parsec di un blazar ad emissione di neutrini noto come TXS 0506+056.

I risultati del nuovo studio, presentato su arXiv.org, hanno fatto maggiore luce sulle proprietà di questo getto, che potrebbe migliorare la comprensione dei neutrini ad altissima energia (VHE).

I…