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With more than 70% of its surface covered in water, Earth is rightly known as the "blue planet". But where did this water - so essential to life - originate? While some theories suggest that hydrogen was delivered to Earth from space via asteroids, new research indicates that the building blocks for water may have been present on our planet all along. We chat to Tom Barrett from Oxford's Department of Earth Sciences to find out more.
Dominik und Nina sprechen für #ueberdentellerrand mit Sabine Brock, stv. CTO und Leiterin der Abteilung Industry Relation beim DESY. DESY ist die Abkürzung für Deutsches Elektronen-Synchrotron und hat keineswegs etwas mit Daisy, dem Butterblümchen zu tun, wie Sabine bei der Frage danach, was das DESY eigentlich ist, klarstellt. Denn auch, wenn es die Großforschungsanlage bereits seit 1959 in Hamburg gibt, wissen selbst viele Hamburger:innen nicht, was es damit auf sich hat. Tatsächlich zählt es zu den weltweit führenden Beschleunigerzentren. Damit ist DESY nicht nur ein Magnet für jährlich mehr als 3.000 internationale Forschende aus über 40 Nationen, die zu den rund 3.000 hier Mitarbeitenden hinzukommen, sondern auch gefragter Partner in nationalen und internationalen Kooperationen. Welche konkreten Kooperationen das sind und was eigentlich die Industrie der / die Hamburger:in an sich vom DESY habt, erfahrt Ihr in der neuesten Ausgabe von #ueberdentellerrand. LinksSabine Brock auf LinkedIn: https://www.linkedin.com/in/sabinebrock/?originalSubdomain=deDESY: https://www.desy.de/Projekt Transferwelten: https://innovation.desy.de/ueber_uns/projekte/transferwelten/index_ger.htmlScience City Hamburg Bahrenfeld: https://www.sciencecity.hamburg/
Emission du mardi 3 décembre 2024 en direct des couloirs du Ciel Au programme : °Pr Bug (multiples synthétiseurs, boite à rythmes et séquenceurs) en featuring avec Synchrotron (batterie totale et synthétiseurs faits maison) https://four4recordz.bandcamp.com/ °Ecoute de disques Led... Continue Reading →
This week, we're hanging out in the terahertz area of the light spectrum! Sandwiched between infrared light and microwaves, terahertz has been the long-forgotten cousin of the light family. But no longer. At the Australian Synchrotron, intense and focused beams of terahertz light are used to test new materials for carbon capture, clean energy and the next generation of computing.
Mark Leishman catches up with host of RNZ's Our Changing World to hear about her recent adventure to the Australian synchotron.
Viral vectors are a cornerstone of gene therapy and many employ experts in the viral vector services space to help design and produce their specialty vectors. These service providers are experts at making sure you get the vector you want with a titer and purity you need for your application. We're joined in this episode by Dr. Cliff Froelich, Head of Analytical Development for a viral vector services provider. Cliff and his team work with AAV, lentivirus, and other vectors to support multiple, and simultaneous, client projects. Specifically, we dive into how they use various analytical and molecular methods to monitor and assess identity, strength, purity, impurities, potency, efficiency, empty/full ratios, safety, and more. As you might expect, it's not a one-method-does-it-all approach or solution. Yes, digital PCR is in the mix here, and Cliff does a great job of outlining where it shines relative to the other methods they use regularly in their GMP practice. In our career corner portion, you'll hear about Cliff's circuitous career path, which includes stints in the poultry industry and time as a clinical dietitian. Through it all, and into his current role, Cliff brings a passion and genuine interest for the science and its potential to affect lives. Visit the Absolute Gene-ius pageto learn more about the guests, the hosts, and the Applied Biosystems QuantStudio Absolute Q Digital PCR System.
Zudem: Neue Materialien bei harten Kunststoffen ermöglichen Recycling.Und: Trotz sterilem Arbeiten gibt es nach Operationen immer wieder Infektionen. Warum war lange ein Rätsel, aber ein lang gehegter Verdacht scheint sich jetzt zu bestätigen. 00:00 Schlagzeilen 00:40 Licht-Computer: Weltweit forschen Arbeitsgruppen an optischen Technologien, um Daten zu verarbeiten. Computerchips etwa, durch die keine Elektronen flitzen, sondern Lichtteilchen. Daten lassen sich so nicht nur schneller übertragen, sondern es braucht auch weniger Energie. Wir gehen der Frage nach, wie gut solche optischen Chips heute schon sind. 06:30 Rezyklierbarer Plastik: Plastik ist ein vielseitig einsetzbares Material und für viele Anwendungen schier unverzichtbar. Insbesondere auch Hartplastik für alle möglichen Bauteile: Dieser ist leicht, belastbar und leicht zu formen. Doch ist Hartplastik heute kaum rezyklierbar. Forschenden aus Österreich ist es nun gelungen, Duroplaste auf nachhaltiger Basis herzustellen und recycling-fähig zu machen. 11:45 Meldungen: Restauration alter Tonbänder mit dem Synchrotron und erhoffte wissenschaftliche Erkenntnisse aus der jüngsten Sonnenfinsternis. 19:10 Post-OP-Infektionen: Etwa jede 30. Operation führt im Nachhinein zu einer Infektion. Dies, obwohl in den Operationssälen penibel auf sterile Abläufe geachtet wird. Eine neue Studie legt nun nahe, dass viele Infektionen gar nicht von mangelhafter Spitalhygiene herrühren, sondern ihren Ursprung auf der Haut der Patientinnen und Patienten haben. Mehr zum Wissenschaftsmagazin und Links zu Studien: https://www.srf.ch/wissenschaftsmagazin .
The Australian Synchrotron in Melbourne is a super high-tech operation that produces powerful beams of light a million times brighter than the sun. In a partnership between GRDC, the University of South Australia and the University of Queensland, researchers have been given access to the Australian Synchrotron and it's giving them a perspective on soil they've never had before. They're using the Synchrotron's imaging and medical beamline to produce high-quality 3D imagery of roots growing directly into large, undisturbed soil cores. To find out more, we caught up with the University of South Australia's Dr Casey Doolette and Dr Peter Kopittke from the University of Queensland. Download the transcript for this episode Contacts: Dr Peter Kopittke University of Queensland p.kopittke@uq.edu.au Dr Casey Doolette University of South Australia casey.doolette@unisa.edu.au More Information: GRDC YouTube – Crop root research taken to the next level GroundCover – Synchrotron looks deep into wheat's nutritional value GroundCover – Synchrotron technology sheds light on root distribution GRDC Code: UOQ1910-003RTX Learn more about your ad choices. Visit megaphone.fm/adchoices
In his address to the IIEA, Professor Chris Llewellyn Smith discusses the need to complement wind and solar-generated electricity with the ability to store such electricity. He argues that as many countries replace fossil fuels with electricity generated from wind and solar, the volatility of these sources of energy will require storage solutions to be developed to meet a variable demand. Finally, his remarks explore the potential options available to various countries to meet these storage requirements. About the speaker: Chris Llewellyn Smith, who is a theoretical physicist, is currently interested in all aspects of energy supply and demand, especially electricity storage. He led the recently launched study by the Royal Society on Large-Scale Energy Storage. Chris has, inter alia, served as Director of Energy Research, University of Oxford (2011-17); President of the Council of Synchrotron-light for Experimental Science and Applications in the Middle East (2008-17); and Director General of CERN (1994-1998), when the Large Hadron Collider was approved and construction started. He has written and spoken widely on science funding, international scientific collaboration and energy issues, and served on many advisory bodies nationally and internationally, including the UK Prime Minister's Advisory Council on Science and Technology (1989-92). Professor Llewellyn Smith's contributions to theoretical particle physics and leadership have been recognised by awards and honours worldwide, including election to the Royal Society (1984), which awarded him a Royal Medal in 2015.
A particle accelerator is something that scientists use to study the behavior of particles and conduct physics experiments. These machines use an electromagnetic field to make tiny particles move at practically the speed of light: a whopping 186,000 miles per second! So, yeah, a guy stuck his head in one of those… and actually survived! The incident happened in Russia on July 13, 1978. Anatoli Bugorski was a researcher at the Institute for High Energy Physics and worked with the U-70 Synchrotron, the biggest Soviet atom smasher of the time. On that unfortunate day, the scientist was trying to figure out why a piece of the equipment wasn't working as it should. As he was leaning over the machine, the safety mechanism failed at the worst possible moment. It turned out that the scientist's head was right in the path of a powerful proton beam moving at the speed of light. You ready to hear all about it? Then watch the video! Learn more about your ad choices. Visit megaphone.fm/adchoices
Pełna transkrypcja + foto/video na https://radionaukowe.pl/Podcast działa dzięki: https://patronite.pl/radionaukowe Dziękuję!***- Funkcjonujemy dzięki zasilaniu przez promieniowanie elektromagnetyczne ze Słońca. W związku z tym wiedza, jak materia oddziałuje z promieniowaniem elektromagnetycznym, jakie mechanizmy są generowane przez nie generowane, jest niezwykle ważna – podkreśla w Radiu Naukowym prof. Marek Stankiewicz, dyrektor Narodowego Centrum Promieniowania Synchrotronowego Solaris. –Promieniowanie elektromagnetyczne jest tutaj wykorzystywane jako taka sonda, którą możemy zajrzeć w głąb materii. Możemy badać strukturę tej materii, możemy też stymulować pewne reakcje i sprawdzać, czy nie potrafimy ich wykorzystać do naszych celów – dodaje.Centrum Solaris znajduje się w Krakowie. To jedyny taki ośrodek w Polsce. Podobnych na świecie jest wiele, bo promieniowanie synchrotronowe jest bardzo atrakcyjne badawczo. Jest niezwykle jasne, ale to nie jedyna jego zaleta. Pochodzi z rozpędzanych do niemal prędkości światła elektronów. – Elektron emituje promieniowanie w dość szerokim zakresie energetycznym, od podczerwieni do twardych iksów. A na danej linii pomiarowej może pani sobie wybrać dany zakres energetyczny takiego promieniowania. Czyli jest to uniwersalna żarówka – porównuje dr Adriana Wawrzyniak, zastępczyni Dyrektora ds. Akceleratorów.Dr Wawrzyniak oprowadza nas po całym synchrotronie, wyjaśniając m.in. jak zmusza się elektrony do wyemitowania potrzebnego nam światła. Elektrony są przyspieszane, natomiast, jak wiadomo, nie mogą osiągnąć prędkości światła. – Dlatego przy każdym przyspieszeniu w pewien sposób wytracają część tej energii w postaci promieniowania elektromagnetycznego – mówi dr Wawrzyniak. W „Solaris” można prowadzić badania z inżynierii biomedycznej, geologii, biologii, farmakologii czy elektroniki.W podcaście zwierzamy hale synchrotronu, zaglądamy do linii badawczych, sterowni, dowiadujemy się czym żywią się naukowcy pracujący na miejscu non-stop oraz czy jedna mucha może zepsuć eksperyment.Centrum zwiedzam w czasie przerwy technicznej i rozbudowy. Ale już na dniach, 6 marca, urządzenie znów ruszy pełną parą.
Full episode featuring Andy is a very unique as this is the first time we have a scientist working at the interface of two giant fields - nanoscience & artificial intelligence. Our guest Andy of the University of Copenhagen (Denmark) talks about his research, science career, walks, and much more! Find out more at thesciencetalk.com/real-scientists-nano/curators/#curators22
The Second Radio Synchrotron Background Workshop: Conference Summary and Report by J. Singal et al. on Wednesday 30 November We summarize the second radio synchrotron background workshop, which took place June 15-17, 2022 in Barolo, Italy. This meeting was convened because available measurements of the diffuse radio zero level continue to suggest that it is several times higher than can be attributed to known Galactic and extragalactic sources and processes, rendering it the least well understood electromagnetic background at present and a major outstanding question in astrophysics. The workshop agreed on the next priorities for investigations of this phenomenon, which include searching for evidence of the Radio Sunyaev-Zeldovich effect, carrying out cross-correlation analyses of radio emission with other tracers, and supporting the completion of the 310 MHz absolutely calibrated sky map project. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.16547v1
The Second Radio Synchrotron Background Workshop: Conference Summary and Report by J. Singal et al. on Wednesday 30 November We summarize the second radio synchrotron background workshop, which took place June 15-17, 2022 in Barolo, Italy. This meeting was convened because available measurements of the diffuse radio zero level continue to suggest that it is several times higher than can be attributed to known Galactic and extragalactic sources and processes, rendering it the least well understood electromagnetic background at present and a major outstanding question in astrophysics. The workshop agreed on the next priorities for investigations of this phenomenon, which include searching for evidence of the Radio Sunyaev-Zeldovich effect, carrying out cross-correlation analyses of radio emission with other tracers, and supporting the completion of the 310 MHz absolutely calibrated sky map project. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2211.16547v1
A search for thermal gyro-synchrotron emission from hot stellar coronae by Walter W. Golay et al. on Tuesday 29 November We searched for thermal gyro-synchrotron radio emission from a sample of five radio-loud stars whose X-ray coronae contain a hot ($T_e>10^7$ K) thermal component. We used the JVLA to measure Stokes I and V/I spectral energy distributions (SEDs) over the frequency range 15--45 GHz, determining the best-fitting model parameters using power-law and thermal gyro-synchrotron emission models. The SEDs of the three chromospherically active binaries (Algol, UX Arietis, HR 1099) were well-fit by a power-law gyro-synchrotron model, with no evidence for a thermal component. However, the SEDs of the two weak-lined T Tauri stars (V410 Tau, HD 283572) had a circularly polarized enhancement above 30 GHz that was inconsistent with a pure power-law distribution. These spectra were well-fit by summing the emission from an extended coronal volume of power-law gyro-synchrotron emission and a smaller region with thermal plasma and a much stronger magnetic field emitting thermal gyro-synchrotron radiation. We used Bayesian inference to estimate the physical plasma parameters of the emission regions (characteristic size, electron density, temperature, power-law index, and magnetic field strength and direction) using independently measured radio sizes, X-ray luminosities, and magnetic field strengths as priors, where available. The derived parameters were well-constrained but somewhat degenerate. The power-law and thermal volumes in the pre-main-sequence stars are probably not co-spatial, and we speculate they may arise from two distinct regions: a tangled-field magnetosphere where reconnection occurs and a recently discovered axisymmetric toroidal magnetic field, respectively. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2210.11440v2
A search for thermal gyro-synchrotron emission from hot stellar coronae by Walter W. Golay et al. on Monday 28 November We searched for thermal gyro-synchrotron radio emission from a sample of five radio-loud stars whose X-ray coronae contain a hot ($T_e>10^7$ K) thermal component. We used the JVLA to measure Stokes I and V/I spectral energy distributions (SEDs) over the frequency range 15--45 GHz, determining the best-fitting model parameters using power-law and thermal gyro-synchrotron emission models. The SEDs of the three chromospherically active binaries (Algol, UX Arietis, HR 1099) were well-fit by a power-law gyro-synchrotron model, with no evidence for a thermal component. However, the SEDs of the two weak-lined T Tauri stars (V410 Tau, HD 283572) had a circularly polarized enhancement above 30 GHz that was inconsistent with a pure power-law distribution. These spectra were well-fit by summing the emission from an extended coronal volume of power-law gyro-synchrotron emission and a smaller region with thermal plasma and a much stronger magnetic field emitting thermal gyro-synchrotron radiation. We used Bayesian inference to estimate the physical plasma parameters of the emission regions (characteristic size, electron density, temperature, power-law index, and magnetic field strength and direction) using independently measured radio sizes, X-ray luminosities, and magnetic field strengths as priors, where available. The derived parameters were well-constrained but somewhat degenerate. The power-law and thermal volumes in the pre-main-sequence stars are probably not co-spatial, and we speculate they may arise from two distinct regions: a tangled-field magnetosphere where reconnection occurs and a recently discovered axisymmetric toroidal magnetic field, respectively. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2210.11440v2
A search for thermal gyro-synchrotron emission from hot stellar coronae by Walter W. Golay et al. on Monday 28 November We searched for thermal gyro-synchrotron radio emission from a sample of five radio-loud stars whose X-ray coronae contain a hot ($T_e>10^7$ K) thermal component. We used the JVLA to measure Stokes I and V/I spectral energy distributions (SEDs) over the frequency range 15--45 GHz, determining the best-fitting model parameters using power-law and thermal gyro-synchrotron emission models. The SEDs of the three chromospherically active binaries (Algol, UX Arietis, HR 1099) were well-fit by a power-law gyro-synchrotron model, with no evidence for a thermal component. However, the SEDs of the two weak-lined T Tauri stars (V410 Tau, HD 283572) had a circularly polarized enhancement above 30 GHz that was inconsistent with a pure power-law distribution. These spectra were well-fit by summing the emission from an extended coronal volume of power-law gyro-synchrotron emission and a smaller region with thermal plasma and a much stronger magnetic field emitting thermal gyro-synchrotron radiation. We used Bayesian inference to estimate the physical plasma parameters of the emission regions (characteristic size, electron density, temperature, power-law index, and magnetic field strength and direction) using independently measured radio sizes, X-ray luminosities, and magnetic field strengths as priors, where available. The derived parameters were well-constrained but somewhat degenerate. The power-law and thermal volumes in the pre-main-sequence stars are probably not co-spatial, and we speculate they may arise from two distinct regions: a tangled-field magnetosphere where reconnection occurs and a recently discovered axisymmetric toroidal magnetic field, respectively. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2210.11440v2
Synchrotron emission from virial shocks around stacked OVRO-LWA galaxy clusters by Kuan-Chou Hou et al. on Tuesday 18 October Galaxy clusters accrete mass through large scale, strong, structure-formation shocks. Such a virial shock is thought to deposit fractions $xi_e$ and $xi_B$ of the thermal energy in cosmic-ray electrons (CREs) and magnetic fields, respectively, thus generating a leptonic virial ring. However, the expected synchrotron signal was not convincingly established until now. We stack low-frequency radio data from the OVRO-LWA around the 44 most massive, high latitude, extended MCXC clusters, enhancing the ring sensitivity by rescaling clusters to their characteristic, $R_{500}$ radii. Both high (73 MHz) and co-added low ($36text{--}68text{ MHz}$) frequency channels separately indicate a significant ($4text{--}5sigma$) excess peaked at $(2.4 text{--} 2.6) R_{500}$, coincident with a previously stacked Fermi $gamma$-ray signal interpreted as inverse-Compton emission from virial-shock CREs. The stacked radio signal is well fit (TS-test: $4$--$6sigma$ at high frequency, $4$--$8sigma$ at low frequencies, and $8$--$10sigma$ joint) by virial-shock synchrotron emission from the more massive clusters, with $dot{m}xi_exi_Bsimeq (1text{--}4)times 10^{-4}$, where $dot{m}equiv dot{M}/(MH)$ is the dimensionless accretion rate for a cluster of mass $M$ and a Hubble constant $H$. The inferred CRE spectral index is flat, $p simeq 2.0 pm 0.2$, consistent with acceleration in a strong shock. Assuming equipartition or using $dot{m}xi_esim0.6%$ inferred from the Fermi signal yields $xi_Bsimeq (2text{--}9)%$, corresponding to $B simeq (0.1text{--}0.3)~mutext{G}$ magnetic fields downstream of typical virial shocks. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2210.09317v1
The Synchrotron Low-Energy Spectrum Arising from the Cooling of Electrons in Gamma-Ray Bursts by A. D. Panaitescu et al. on Wednesday 21 September This work is a continuation of a previous effort (Panaitescu 2019) to study the cooling of relativistic electrons through radiation (synchrotron and self-Compton) emission and adiabatic losses, with application to the spectra and light-curves of the synchrotron Gamma-Ray Burst produced by such cooling electrons. Here, we derive the low-energy slope b_LE of GRB pulse-integrated spectrum and quantify the implications of the measured distribution of b_LE. If the magnetic field lives longer than it takes the cooling GRB electrons to radiate below 1-10 keV, then radiative cooling processes of power P(gamma) ~ gamma^n with n geq 2, i.e. synchrotron and inverse-Compton (iC) through Thomson scatterings, lead to a soft low-energy spectral slope b_LE leq -1/2 of the GRB pulse-integrated spectrum F_eps ~ eps^{b_LE} below the peak-energy E_p, irrespective of the duration of electron injection t_i. IC-cooling dominated by scatterings at the Thomson--Klein-Nishina transition of synchrotron photons below E_p has an index n = 2/3 -> 1 and yield harder integrated spectra with b_LE in [0,1/6], while adiabatic electron-cooling leads to a soft slope b_LE = -3/4. Radiative processes that produce soft integrated spectra can accommodate the harder slopes measured by CGRO/BATSE and Fermi/GBM only if the magnetic field life-time t_B is shorter than the time during which the typical GRB electrons cool to radiate below 1-10 keV, which is less than (at most) ten radiative cooling timescales t_rad of the typical GRB electron. In this case, there is a one-to-one correspondence between t_B and b_LE. To account for low-energy slopes b_LE > -3/4, adiabatic electron-cooling requires a similar restriction on t_B. In this case, the diversity of slopes arises mostly from how the electron-injection rate varies with time and not from the magnetic field timescale. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2209.10014v1
A Foreground Model Independent Bayesian CMB Temperature and Polarization Signal Reconstruction and Cosmological Parameter Estimation over Large Angular Scales by Albin Joseph et al. on Thursday 15 September Recent CMB observations have resulted in very precise observational data. A robust and reliable CMB reconstruction technique can lead to efficient estimation of the cosmological parameters. We demonstrate the performance of our methodology using simulated temperature and polarization observations using cosmic variance limited future generation PRISM satellite mission. We generate samples from the joint distribution by implementing the CMB inverse covariance weighted internal-linear-combination (ILC) with the Gibbs sampling technique. We use the Python Sky Model (PySM), d4f1s1 to generate the realistic foreground templates. The Synchrotron is parametrized by a spatially varying spectral index, whereas thermal dust is described as two component dust model. We estimate the marginalized densities of CMB signal ${bf S}$ and theoretical angular power spectrum $C_{ell}$ utilizing the samples from the entire posterior distribution. The best-fit cleaned CMB map and the corresponding angular power spectrum are consistent with the CMB realization and the sky $C_{ell}$ implying an efficient foreground minimized reconstruction. The likelihood function $P(C_{ell}|{bf D}$) estimated by making use of the Blackwell-Rao estimator is used for the estimation of the cosmological parameters. Our methodology can estimate tensor to scalar ratio $rge 0.0075$. Our current work demonstrates an analysis pipeline starting from the reliable estimation of CMB signal and its angular power spectrum to the case of cosmological parameter estimation using the foreground model independent Gibbs-ILC method. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2209.07179v1
Synchrotron Pair Production Equilibrium in Relativistic Magnetic Reconnection by Alexander Y. Chen et al. on Thursday 08 September Magnetic reconnection is ubiquitous in astrophysical systems, and in many such systems, the plasma suffers from significant cooling due to synchrotron radiation. We study relativistic magnetic reconnection in the presence of strong synchrotron cooling, where the ambient magnetization $sigma$ is high and the magnetic compactness $ell_{B}$ of the system is of order unity. In this regime, $e^{pm}$ pair production from synchrotron photons is inevitable, and this process can regulate the magnetization $sigma$ surrounding the current sheet. We investigate this self-regulation analytically and find a self-consistent steady state for a given magnetic compactness of the system and initial magnetization. This result helps estimate the self-consistent upstream magnetization in systems where plasma density is poorly constrained, and can be useful for a variety of astrophysical systems. As illustrative examples, we apply it to study the properties of reconnecting current sheets near the supermassive black hole of M87, as well as the equatorial current sheet outside the light cylinder of the Crab pulsar. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2209.03249v1
Synchrotron Pair Production Equilibrium in Relativistic Magnetic Reconnection by Alexander Y. Chen et al. on Thursday 08 September Magnetic reconnection is ubiquitous in astrophysical systems, and in many such systems, the plasma suffers from significant cooling due to synchrotron radiation. We study relativistic magnetic reconnection in the presence of strong synchrotron cooling, where the ambient magnetization $sigma$ is high and the magnetic compactness $ell_{B}$ of the system is of order unity. In this regime, $e^{pm}$ pair production from synchrotron photons is inevitable, and this process can regulate the magnetization $sigma$ surrounding the current sheet. We investigate this self-regulation analytically and find a self-consistent steady state for a given magnetic compactness of the system and initial magnetization. This result helps estimate the self-consistent upstream magnetization in systems where plasma density is poorly constrained, and can be useful for a variety of astrophysical systems. As illustrative examples, we apply it to study the properties of reconnecting current sheets near the supermassive black hole of M87, as well as the equatorial current sheet outside the light cylinder of the Crab pulsar. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2209.03249v1
Testing synchrotron models and frequency resolution in BINGO 21 cm simulated maps using GNILC by Eduardo J. de Mericia et al. on Thursday 08 September To recover the 21 cm hydrogen line, it is essential to separate the cosmological signal from the much stronger foreground contributions at radio frequencies. The BINGO radio telescope is designed to measure the 21 cm line and detect BAOs using the intensity mapping technique. This work analyses the performance of the GNILC method, combined with a power spectrum debiasing procedure. The method was applied to a simulated BINGO mission, building upon previous work from the collaboration. It compares two different synchrotron emission models and different instrumental configurations, in addition to the combination with ancillary data to optimize both the foreground removal and recovery of the 21 cm signal across the full BINGO frequency band, as well as to determine an optimal number of frequency bands for the signal recovery. We have produced foreground emissions maps using the Planck Sky Model, the cosmological Hi emission maps are generated using the FLASK package and thermal noise maps are created according to the instrumental setup. We apply the GNILC method to the simulated sky maps to separate the Hi plus thermal noise contribution and, through a debiasing procedure, recover an estimate of the noiseless 21 cm power spectrum. We found a near optimal reconstruction of the Hi signal using a 80 bins configuration, which resulted in a power spectrum reconstruction average error over all frequencies of 3%. Furthermore, our tests showed that GNILC is robust against different synchrotron emission models. Finally, adding an extra channel with CBASS foregrounds information, we reduced the estimation error of the 21 cm signal. The optimisation of our previous work, producing a configuration with an optimal number of channels for binning the data, impacts greatly the decisions regarding BINGO hardware configuration before commissioning. arXiv: http://arxiv.org/abs/http://arxiv.org/abs/2204.08112v2
Tara and Jamie talk about 'the suitcase scientist.' They explore the synchrotron and its role, not only in scientific discovery but also urban, regional and national development. How can mobile scientists enable mobile knowledge?
In this podcast we learn how to cook with the Sun and how to create a scientific board game
The end-Cretaceous mass extinction was a cataclysmic asteroid impact that ushered in the end of the non-avian dinosaurs and forever changed the course of evolution on Earth. But what can we say about the timing of the event, other than it happened 66 million years ago? Well, it turns out that Tanis, a relatively-recently discovered fossil site in North Dakota, is full of lines of evidence that are allowing earth scientists to piece together when the impact occurred. In this episode, we're joined by Melanie During, Uppsala University, who has been examining the details of the bones of fish to say more about the world either side of the event.