POPULARITY
My research focuses on looking at black holes. Some black holes are so energetic, that they tear up the bright hot matter spinning around them and funnel it into jets shooting out their top and bottom. And once in a while, we luck out and a few black holes are oriented so that the jets are pointed straight towards the earth! We call these kinds of black holes Blazars, and it's my job to look at their most energetic and extreme cases and try to figure out if there are any neutrinos in those jets! If we can find neutrinos coming out of them, we can follow their trail back to what in the jet created them and learn more about black holes themselves! For upcoming interviews check out the Grad Chat webpage on Queen’s University School of Graduate Studies & Postdoctoral Affairs website.
Blazars are just quasars that are pointed at us? That's it? Yep, that's it according to our guest, PhD candidate Emily Kerrison, in our latest, 'scintillating' episode. Do you mean 'scintillating' as in 'radio scintillation'? The same! Joining us from the University of Sydney, Australia, Emily tells Kovi and Benjamin the ins and outs of AGNs (Active Galactic Nuclei). Quasars, blazars, and BL Lac objects - oh my!
Hot takes on California Reparations.☆☆Recipes. ☆☆Quick Tips. ☆☆ Fun Facts.☆☆ Trivia: "Galaxies, Supermassive Black Holes, Quasars and Blazars!" ☆☆Open Book Quiz(: ☆Bible Selections.☆For Educational Purposes. The Creators own their content.
The universe is filled with brilliant black holes. They shine like beacons, visible from billions of light-years away. And they fire “particle beams” toward Earth — jets of hot gas moving at almost the speed of light. They're called “blazars.” These supermassive black holes inhabit the cores of galaxies. And just to be clear, it's not the black holes themselves that are bright. Black holes are completely dark — they emit no light of any kind. But a black hole's gravity pulls in gas, dust, and stars. The material spirals around the black hole at high speed, forming a disk. Friction in the disk heats it to millions of degrees, so it shines brighter than entire galaxies of stars. So far, that description also fits another class of objects, known as quasars. What sets a blazar apart is a jet of super-heated gas, known as plasma, shooting away from the poles of the black hole. Heat inside the disk rips atoms apart, giving the material an electric charge. Powerful magnetic fields in the disk scoop up some of the charged particles before they can disappear into the black hole. They shoot the particles into space at just below lightspeed. If one of the beams happens to aim toward Earth, it makes the object look especially bright — a blazar. Astronomers have located thousands of them, with more joining the lineup all the time — bright black holes taking aim at Earth. More about black holes tomorrow. Script by Damond Benningfield Support McDonald Observatory
This podcast is a commentary and does not contain any copyrighted material of the reference source. We strongly recommend accessing/buying the reference source at the same time. ■Reference Source https://www.ted.com/talks/jedidah_isler_how_i_fell_in_love_with_quasars_blazars_and_our_incredible_universe ■Post on this topic (You can get FREE learning materials!) https://englist.me/71-academic-words-reference-from-jedidah-isler-how-i-fell-in-love-with-quasars-blazars-and-our-incredible-universe-ted-talk/ ■Youtube Video https://youtu.be/N_DFzMtKUpg (All Words) https://youtu.be/rN9okmLe2eQ (Advanced Words) https://youtu.be/qL988D0D4AA (Quick Look) ■Top Page for Further Materials https://englist.me/ ■SNS (Please follow!)
In today's episode, Kolby and Dawson break down the insane interstellar objects that are quasars, blazars, and pulsars. That, plus science news about a potential nearby supernova and the reality that not all infinities are the same size as other infinities should get your science itch scratched this Saturday. Check out our website, Patreon, socials, and more!
The RATAN-600 multi-frequency catalogue of blazars -- BLcat by Yu. Sotnikova et al. on Tuesday 22 November In this paper we present the RATAN-600 multi-frequency catalogue of blazars, an updated version of the BLcat: the RATAN-600 multi-frequency catalogue of BL Lacertae objects. The main novelty in the catalogue is an extension of the sample with flat-spectrum radio quasars (FSRQs), thus currently it contains more than 1700 blazars of different types. The main feature of the BLcat is a compilation of radio continuum data for blazars based on the RATAN-600 quasi-simultaneous measurements at frequencies of 1.1, 2.3, 4.7, 7.7/8.2, 11.2, and 21.7/22.3 GHz. We additionally supplement the catalogue with the radio data from external sources to provide an opportunity to more complete study of radio spectra and radio light curves. For the convenience of users, we developed tools to calculate the spectral index, variability index, and radio luminosity. We briefly describe basic radio properties of blazar subsamples of the catalogue: spectral classification, spectral indices, flux density variability, and radio luminosity. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.11279v1
Growing evidence for high-energy neutrinos originating in radio blazars by A. V. Plavin et al. on Monday 21 November Evidence for bright radio blazars being high-energy neutrino sources was found in recent years. Specifics of how and where these particles get produced still remain not fully determined. In this paper, we add 14 new IceCube detections from 2020-2022 to update our analysis of the neutrino-blazars connection. We test and refine earlier findings by utilizing the total of 71 track-like high-energy IceCube events from 2009-2022. We correlate them with the complete sample of 3412 extragalactic radio sources selected by their compact radio emission. We demonstrate that neutrinos are statistically associated with radio-bright blazars with the post-trial p-value of 3*10^-4. In addition to this statistical study, we confirm previous individual neutrino-blazar associations, find and discuss several new ones. Notably, PKS 1741-038 was selected earlier and had the second neutrino detected from its direction in 2022; PKS 0735+168 has experienced a major flare across the whole electromagnetic spectrum coincidently with a neutrino arrival from that direction in 2021. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.09631v1
The RATAN-600 multi-frequency catalogue of blazars -- BLcat by Yu. Sotnikova et al. on Monday 21 November In this paper we present the RATAN-600 multi-frequency catalogue of blazars, an updated version of the BLcat: the RATAN-600 multi-frequency catalogue of BL Lacertae objects. The main novelty in the catalogue is an extension of the sample with flat-spectrum radio quasars (FSRQs), thus currently it contains more than 1700 blazars of different types. The main feature of the BLcat is a compilation of radio continuum data for blazars based on the RATAN-600 quasi-simultaneous measurements at frequencies of 1.1, 2.3, 4.7, 7.7/8.2, 11.2, and 21.7/22.3 GHz. We additionally supplement the catalogue with the radio data from external sources to provide an opportunity to more complete study of radio spectra and radio light curves. For the convenience of users, we developed tools to calculate the spectral index, variability index, and radio luminosity. We briefly describe basic radio properties of blazar subsamples of the catalogue: spectral classification, spectral indices, flux density variability, and radio luminosity. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.11279v1
Probable low-frequency quasi-periodic oscillations in blazars from the ZTF survey by Anuvab Banerjee et al. on Sunday 16 October We investigate the possible presence of quasi-periodic oscillation (QPO) signals in 2103 blazars from the Zwicky Transient Facility (ZTF) time-domain survey. We detect a low frequency QPO signal in five blazars observed over these 3.8 year long optical r-band ZTF light curves. These periods range from 144 days to 196 days detected at $gtrsim4sigma$ significance levels in both the Lomb-Scargle periodogram and Weighted Wavelet Z-transform analyses. A similar peak is detected in the g-band light-curve at a slightly lower significance of 3$sigma$. Such nearly periodic signals on these timescales in optical wavebands most likely originate from a precessing jet with high Lorentz factor, closely aligned to the observer's line of sight, or the movement of plasma blobs along a helical structure in the jet. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2210.07266v1
Moderate Correlation between the Accretion Disk and Jet Power in a Large Sample of Fermi Blazars by Garima Rajguru et al. on Monday 26 September We present the results of studying the accretion disk vs jet power for a large fraction of all the blazars detected by the Fermi Gamma-Ray Space Telescope. The disk power is inferred from the emission line luminosities obtained from published results. As indicators of jet power, we use low frequency radio luminosity from the extended jet, maximum speed of radio knots observed in the VLBA monitoring of the pc-scale jets, kinetic energy of electrons in the jet deduced from the best-fit theoretical models of their spectral energy distribution, and gamma-ray luminosity with and without beaming correction. We obtain a significant correlation in most of those cases. However, we find that the correlations are often driven by the common redshift dependence of the compared quantities. In order to remove the redshift bias and probe the intrinsic correlation between the disk and jet power, we compute the partial correlation coefficient as well as the correlation in small redshift bins, and find that the intrinsic disk-jet correlation is still present but weaker. In the cases, in which the common redshift dependence does not affect the result, we find that blazars do not exhibit high jet power for low disk luminosities while there are both high and low jet power for high disk luminosities. This result indicates that a powerful disk is a necessary but not sufficient condition to produce a powerful jet. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2209.12264v1
BASS XXXIII: Swift-BAT blazars and their jets through cosmic time by L. Marcotulli et al. on Wednesday 21 September We derive the most up-to-date Swift-Burst Alert Telescope (BAT) blazar luminosity function in the 14-195 keV range, making use of a clean sample of 118 blazars detected in the BAT 105-month survey catalog, with newly obtained redshifts from the BAT AGN Spectroscopic Survey (BASS). We determine the best-fit X-ray luminosity function for the whole blazar population, as well as for Flat Spectrum Radio Quasars (FSRQs) alone. The main results are: (1) at any redshift, BAT detects the most luminous blazars, above any possible break in their luminosity distribution, which means we cannot differentiate between density and luminosity evolution; (2) the whole blazar population, dominated by FSRQs, evolves positively up to redshift z~4.3, confirming earlier results and implying lower number densities of blazars at higher redshifts than previously estimated. The contribution of this source class to the Cosmic X-ray Background at 14-195 keV can range from 5-18%, while possibly accounting for 100% of the MeV background. We also derived the average 14 keV-10 GeV SED for BAT blazars, which allows us to predict the number counts of sources in the MeV range, as well as the expected number of high-energy (>100 TeV) neutrinos. A mission like COSI, will detect 40 MeV blazars and 2 coincident neutrinos. Finally, taking into account beaming selection effects, the distribution and properties of the parent population of these extragalactic jets are derived. We find that the distribution of viewing angles is quite narrow, with most sources aligned within < 5{deg} of the line of sight. Moreover, the average Lorentz factor, = 8-12, is lower than previously suggested for these powerful sources. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2209.09929v1
X-ray Intraday Variability of HBL Blazars with XMM-Newton by P. U. Devanand et al. on Tuesday 13 September We present an extensive study on the X-ray intraday variability of ten TeV-emitting high synchrotron peaked blazars (HBLs): 1ES 0229+200, 1ES 0414+009, PKS 0548-322, 1ES 1101-232, 1H 1219+301, H 1426+428, Mrk 501, 1ES 1959+650, PKS 2005-489, and 1ES 2344+514 made with twenty-five XMM-Newton pointed observations during its operational period. Intraday variability has been estimated in three energy bands: soft (0.3--2 keV), hard (2--10 keV) and total (0.3--10 keV). Although seven out of these ten TeV HBLs exhibited some intraday variability at three-sigma levels no major variations exceeding six percent were detected. We explored the spectral properties of the sample by extracting the hardness ratio from the soft and hard bands; no significant variations in the hardness ratio were observed in any source. We performed power spectral density analyses on the variable light-curves by fitting power-laws, yielding slopes lying in the range from 1.11 to 2.93 for different HBLs. We briefly discuss possible emission mechanisms and carry out rough estimates for magnetic fields, electron Lorentz factors and emission region sizes for seven of these HBLs. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2209.05515v1
What is a quasar? What is a blazer? Tune in and find out. See omnystudio.com/listener for privacy information.
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Blazars are some of the brightest and most vibrant objects known to astronomers: emitting high-velocity jets of matter, and producing gamma rays which outshine almost all other sources in the known universe. To study these phenomena, astronomers must use the latest techniques to observe blazars simultaneously at different wavelengths of electromagnetic radiation, while also capturing the elusive neutrinos they emit. In a recent article, Dr Markus Böttcher, an astronomer at North-West University on Potchefstroom, South Africa, presents an overview of the latest advances in these ‘multiwavelength' and ‘multi-messenger' techniques – and where they could lead in the near future.
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Françoise Combes Collège de France Galaxies et cosmologie Année 2021 - 2022 Les phénomènes variables en astrophysique : des sursauts gamma aux blazars
Learn about what online trolls are like in real life; an auditory illusion rattlesnakes use to trick humans; and blazars. Online trolling might be due to personality rather than the anonymity of the internet by Steffie Drucker New research: The internet does not turn people into trolls – it just makes real-life trolls more visible. (2021, August 26). EurekAlert! https://www.eurekalert.org/news-releases/926582 BOR, A., & PETERSEN, M. B. (2021). The Psychology of Online Political Hostility: A Comprehensive, Cross-National Test of the Mismatch Hypothesis. American Political Science Review, 1–18. https://doi.org/10.1017/s0003055421000885 Rattlesnake rattles use auditory illusion to trick human brains by Cameron Duke Forsthofer, M., Schutte, M., Luksch, H., Kohl, T., Wiegrebe, L., & Chagnaud, B. P. (2021). Frequency modulation of rattlesnake acoustic display affects acoustic distance perception in humans. Current Biology. https://doi.org/10.1016/j.cub.2021.07.018 Turner, B. (2021, August 19). Rattlesnake rattles use auditory illusion to trick human brains. Livescience.com; Live Science. https://www.livescience.com/rattlesnakes-trick-brains-auditory-illusion.html Introducing The Universe's Most Epic Object: The Blazar by Ashley Hamer Atkinson, Nancy. (2009, March 19). Astronomers Observe Bizarre Blazar with Battery of Telescopes. Universe Today. https://www.universetoday.com/27518/astronomers-observe-bizarre-blazar-with-battery-of-telescopes/ Carlson, E. K. (2018, July 12). Blazars explained. Astronomy.com. https://astronomy.com/news/2018/07/what-is-a-blazar Follow Curiosity Daily on your favorite podcast app to learn something new every day withCody Gough andAshley Hamer. Still curious? Get exclusive science shows, nature documentaries, and more real-life entertainment on discovery+! Go to https://discoveryplus.com/curiosity to start your 7-day free trial. discovery+ is currently only available for US subscribers. See omnystudio.com/listener for privacy information.
My next guest is an astrophysicist who works at NASA's Goddard Space Flight Center. I'm speaking about none other than my friend, Joe Eggen. Aside from being the father of my daughter's best friend, Joe is your friendly neighborhood science guy. He earned his Ph. D. in Astronomy and Physics at Georgia State University where he did his dissertation on "Optical Polarimetry and Gamma-Ray Observations of a Sample of Radio-Loud Narrow Line Seyfert 1 Galaxies." I don't know what that means, and neither do you.Joe and I get into:How stars create new elements through fusionNeutrinos, gamma rays, and gravitational wavesHis gripe with the way people talk about geniusesThe era of multi-messenger astronomyPulsars, Quasars, and Blazars, oh my!And of course, his take on the most recent unexplained arial phenomenon ... the aliens.Learn more about Joe and the work he does with the Fermi Gamma-ray Space Telescope!References:Tabetha Boyajian's TED talk on The Most Mysterious Star in the Universe: https://www.ted.com/talks/tabetha_boyajian_the_most_mysterious_star_in_the_universeThe next total solar eclipse in the Americas comes on April 8, 2024. Totality first touches Mexico, enters the United States at Texas, cuts a diagonal to Maine, and visits the maritime provinces of Canada.
Derfor skal du lytte:Hvis du tænker succesfuld karriere ved et af verdens største konsulenthuse, founder af en succesfuld virksomhedsfabrik og samtdig dommer i landets mest populære start-up tv-program, så forestiller du dig nok ikke at vedkommende har en alder på 32 år? I Christian Arnstedts tilfælde, så er det dog præcist det der er tilfældet og i denne podcast kan du høre hans vigtigste erfaringer fra hans kometkarriere og hvordan mindsettet fra elitesport har hjulpet ham til en international start- up succes. Episode 49: Rollemodellerne podcast med Christian Arnstedt Start iværksætterfesten tidligt: Sådan overfører du mindsettet fra elitesport til international start-up succes(function($) {$("head").append("#dfd-heading-5ff5b2b004768 .dfd-heading-module {}#dfd-heading-5ff5b2b004768 .dfd-heading-delimiter {border-bottom-style: solid;width: 80px;border-bottom-width: 1px;}#dfd-heading-5ff5b2b004768 .dfd-title {margin-bottom: 30px;}#dfd-heading-5ff5b2b004768 .dfd-sub-title{margin-bottom: 30px;}#dfd-heading-5ff5b2b004768 .dfd-heading-delimiter {margin-top: 10px;margin-bottom: 10px;}");})(jQuery); Sponsor Rollemodellerne er sponsoreret af Danmarks største streamingtjeneste for bøger og lydbøger Mofibo. Hvis du vil have gratis adgang til mere end 250.000 forskellige bøger, og samtidig støtte Rollemodellerne, så kan du få 30 dage gratis som ny kunde på Mofibo. Du skal bare bruge bonuskoden ROLLEMODELLERNE når du opretter din konto. Hvem er Christian Arnstedt? Hvis der er et ord som kendetegner Christian Arnstedt, så vil det være kometkarriere. Christian dyrkede elitesport allerede i en ung alder, og han tog den hurtige vej ved at tage en uddannelse fra London School of Economics på rekordtid, hvilket førte ham ind som en af de yngste junior partnere i det anerkendte konsulenthus McKinsey nogensinde. Efter en flot karriere ved McKinsey tog Christian et markant valg og skiftede til den usikre vej som iværksætter, da han sammen med nogle venner startede virksomhedsfabrikken Blazar Capital, hvor specielt urmærket Nordgreen har været en stor succes, som nu sælges på en lang række internationale markeder. Blazars kendetegn er at bygge internationale B2C forretninger. Christian er desuden sprunget ind som ny løve i DRs populære iværksætterprogram Løvens Hule, som den yngste nogensinde. Her markerede han sig allerede i sin første sæson med en række markante investeringer herunder den største i programmets historie. Hvorfor er Christian gæst i Rollemodellerne? Rollemodellernes vigtigste mission er at give taletid til netop de mennesker, som kan inspirere andre til at gå efter drømmen og kan bryde normerne. For mig er Christian et rigtigt godt eksempel på netop det og derfor er han en naturlig deltager. Det faktum at han som 32 årig har en omfangsrig erhvervskarriere, som omfatter både en flot karriere i McKinsey og at han er lykkedes med at skabe en stor iværksætter succes med Blazar, er noget som aftvinger respekt og beundring. Der er ingen tvivl om at han for alvor stemplede ind, som en populær dommer, i Løvens Hule, og der var det befriende for seerne at se, at man sagtens kan investere i start-ups, selvom man ikke har mange år på bagen. Lytterne elskede desuden interviewene fra sidste sæson med de to andre løver Jacob Risgaard og Mia Wagner - så derfor var det naturligt at Christian også delte sin erfaring og sit perspektiv. I dagens podcast kan du bl.a. høre om: Den kuriøse historie om Christians første iværksættereventyr Hvilke ting Christian tog med fra elitesport til sin erhvervskarriere Hvordan han fandt sammen med sine venner om at stifte Blazar Capital Hvilke læringer de har fået fra at drive en række internationale E-commerce forretninger Christians vigtigste inspirationskilder Godt nytår og tak fordi du lytter med! Rollemodellerne - Her starter du med den bedste inspiration Kh Bjørn (function($) {$("head").
When you think of a telescope you might picture a long tube with lenses, mirrors and a tripod picking up the light that is visible to us. But there are actually several different types that pick up other wavelengths we can’t see. Dotted across Europe, the The Low Frequency Array (LOFAR) radio telescope network is attempting to map the entire night sky, and one of them located right here in Ireland. Sean Mooney, PhD student at UCD School of Physics and member of the LOFAR Surveys Key Science Project joins Jonathan in studio to discuss.
Feature Guest: Darren Grant A one hundred year old astronomical mystery may finally have been solved. Scientists have long wondered just what caused high energy particles called cosmic rays, which arrive on Earth from the far unknown reaches of the universe. But now we have a discovery by the South Pole Neutrino Observatory, appropriately named IceCube, which points the finger at a peculiar phenomena known as blazars. The IceCube Collaboration’s Professor Darren Grant joins us today here at The Star Spot. Current in Space Dave reports on the arrival of the Osiris-Rex mission at the asteroid Bennu. Then, when it comes to climate change, desperate times call for desperate measures, such as the plan we hear from Simon to spray chemicals into the atmosphere to reflect the sun’s heat back into space. And Tony explains the possible outcome of an astronomical event so energetic we detected its gravitational waves back in August 2017. Finally Amelia tells us we may have finally come a step closer to understanding what fuels the least-understood type of supernova. About Our Guest Darren Grant is Assistant Professor of Physics at the University of Alberta. He is the Spokesperson for the IceCube Collaboration, referring to the South Pole Neutrino Observatory. Grant is Canada Research Chair in Astroparticle Physics and received an E.W.R. Steacie Memorial Fellowship from the Natural Sciences and Engineering Research Council of Canada.
Syzygy is produced by Chris Stewart and co-hosted by Dr Emily Brunsden from the Department of Physics at the University of York.Find us on Twitter: @syzygypod twitter.com/SyzygyPodOr just visit us at home: syzygy.fmEmily at the University of York: www.york.ac.uk/physics/people/brunsden/Chris online: kipstewart.comTo view the podcast chapter list and artwork in this episode, you could do worse than use the Overcast app on iOS, or Pocket Casts on Android. (Other podcast players are available, though they may not handle mp3 chapters nicely.)Some of the things we talk about in this episode:All the latest TESS news! https://tess.mit.edu/news/TESS’s first light: http://www.syfy.com/syfywire/first-light-for-tessThe Blazar Neutrino — Paper 1: http://science.sciencemag.org/content/361/6398/eaat1378Paper 2: : http://science.sciencemag.org/content/361/6398/147A good article about the IceCube Neutrino: https://www.sciencenews.org/article/high-energy-neutrinos-blazar-icecubeNeutrinos: https://icecube.wisc.edu/info/neutrinosIceCube Neutrino Observatory: https://icecube.wisc.eduIceCube’s stunning Instagram: https://www.instagram.com/icecube_neutrino/Blazars: https://www.universetoday.com/30594/blazars/
Hear an overview of two of the major types of active galaxies: quasars and blazars! I discuss the history of the study of quasars as well as where we're going with future studies of these extragalactic objects.
Teriyaky Boyz - Tokyo Drift 2K18 (#Coppola Future Banger) (Ft. Marnik & Blazars)
SpaceTime with Stuart Gary | Astronomy, Space & Science News
Stream Episodes on demand from www.bitesz.com or www.spacetimewithstuartgary.com (both mobile friendly) *Discovery of the most extreme blazars ever seen NASA's Fermi Gamma-ray Space Telescope has discovered the most distant gamma-ray blazars ever seen. Blazars are powerful jets of particles and energy travelling at close to the speed of light. They’re produced by a supermassive black holes feeding in the centre of a galaxy. *Study reveals substantial evidence of holographic universe A new study has provided what researchers believe is the first observational evidence that the universe could be a vast complex hologram. Physicists investigating irregularities in the cosmic microwave background radiation claim they have found as much evidence supporting a holographic explanation of the universe as there is for the traditional explanation of these irregularities using the theory of cosmic inflation. *Asteroid near miss Astronomers have detected another relatively large asteroid that almost sped past the Earth unnoticed. The space rock designated 2017-AG13 passed the Earth at a distance of less than 200 thousand kilometres -- about half way between the Earth and the Moon. (For more...follow @SpaceNuts podcast from all good podcatcher apps or bitesz.com) *Iran conducts ballistic missile test in violation of UN ban Iran has conducted a ballistic missile test in another violation of United Nations Security Council resolutions. The flight – which occurred on Sunday – was designed to test a new re-entry vehicle warhead fitted to a Khorramshahr ballistic missile. *New generation satellite launches in to orbit Arianespace has launched a Russian Soyuz SZT-B rocket from the European Space Agency’s Kourou spaceport in French Guiana a new type of telecommunications satellite into orbit. The early morning launch lit up the black skies with a golden ribbon of fire as Spain’s Hispasat 36W-1 satellite was lifted into geostationary orbit aboard the soviet era Russian rocket. If you're enjoying SpaceTime, please help out by sharing and telling your friends. The best recommendation I can get is one from you. Thank you... #astronomy #space #science #technology #news #blazars #Iran Learn more about your ad choices. Visit megaphone.fm/adchoices Support this show http://supporter.acast.com/spacetime. See acast.com/privacy for privacy and opt-out information.
Fakultät für Physik - Digitale Hochschulschriften der LMU - Teil 03/05
Active Galactic Nuclei (AGNs) are among the most luminous objects in the universe. At the center of an AGN, there is a SuperMassive Black Hole (SMBH) with a mass above million Solar mass, which is believed to be the engine of a huge energy output. Blazars are a subclass of AGNs, which usually have bipolar jets, one of which is pointing towards us. Markarian 421 (Mrk421) is one of the bright and nearby established TeV blazars. Its TeV emission was first discovered by the Whipple telescope in 1992 and it became one of the most studied extra-galactic objects in the TeV regime. Mrk421 shows strong variabilities in time and amplitude in different energy regimes. The Mrk421 data collected so far from many historic multiwavelength observations is not yet sufficient to fully constrain the theoretical models. In particular, it is not yet clear whether the leptonic or hadronic processes play a decisive role inside the jets. Due to short duty cycles and limited observation time, studies of bright TeV (E > 100 GeV) blazars are mostly restricted to flaring episodes or short time period (a few days to weeks) of multiwavelength campaigns. However, to study these objects long time monitoring is needed in order to constrain theoretical jet models. Only unbiased long-term studies are adequate for the determination of flaring states probabilities and for estimating the statistical significance of possible correlations between TeV flaring states and other observables, like X-ray or neutrinos. Besides, regular observations can also provide triggers for multiwavelength ToO observations. This is particularly necessary for identifying and studying orphan TeV flares. MAGIC has observed Mrk421 since 2004 and then constantly monitored this source from 2006. In this thesis, the Mrk421 data taken from 2005 to 2008 will be presented. The physics results from several times of joint observations will be also discussed. To further increase the sensitivity of the MAGIC telescope, a second telescope was built. The photosensors, PMTs, with light collectors, Winston Cones, of the second telescope were tested in order to know the performance of the new system. The different characteristics of the PMTs and their performance tests will be also described.
Fakultät für Physik - Digitale Hochschulschriften der LMU - Teil 02/05
Blazars, a subclass of active galactic nuclei in which the jet is aligned very close to our line of sight, can accelerate charged particles to relativistic energies in the jet. Electromagnetic emission from this class of sources can be observed from radio up to TeV energies. The MAGIC telescope is an Imaging Atmospheric Cherenkov Telescope with a 17-m diameter dish, located on the Canary Island of La Palma, in operation for exploring a new window of very high energy (VHE) gamma-ray bands, above 50 GeV. Searching for new VHE gamma-ray blazars, BL Lacertae was observed with the MAGIC telescope in 2005 and 2006. A VHE gamma-ray signal was discovered with a 5.1 sigma excess in the 2005 data. This discovery established a new class of VHE gamma-ray emitters, "low-frequency peaked BL Lac objects". On the other hand, the 2006 data showed no significant excess. This drop in flux followed the observed trend in the optical activity. The MAGIC telescope continuously observed the bright known blazars Mkn501, 1ES1959+650 and Mkn421. In particular, extensive simultaneous multiwavelength observations with the MAGIC telescope and the X-ray Satellite Suzaku were carried out for Mkn501 in July 2006 and for 1ES1959+650 in May 2006. VHE gamma-ray signals from about 100 GeV to a few TeV were clearly detected. For the first time, the VHE gamma-ray spectra were simultaneously obtained with the X-ray spectra during their low states of activity. Long term observations of Mkn421 in 2006 showed a strong variability in VHE gamma-ray emission. The spectral energy distributions (SEDs) of these four blazars could be well explained by a homogeneous one-zone synchrotron self-Compton model. This model suggests that the variation of the injected electron population in the jet is responsible for observed variations of the SEDs of the blazars. For all sources, the derived magnetic field strength in the jet and the Doppler beaming factor showed similar values. A contribution on the hardware sector is also presented in this thesis. For further lowering energy threshold in the MAGIC project, a new type of photosensor, "HPDs with an 18-mm diameter GaAsP photocathode", were developed. A quantum efficiency of the photocathode could reach over 50 %. Compared to the PMTs currently used in MAGIC, the new photosensors would improve the overall Cherenkov photon conversion efficiency by a factor of 2. Other performance values including lifetime also fulfilled the requirements of photosensors to be used in the MAGIC telescope.