In the latest discovery, the H.E.S.S. (a telescope that is operated by an international collaboration of scientists) has found three extremely luminous gamma-ray sources in the Large Magellanic Cloud (LMC), a satellite dwarf galaxy of the Milky Way.
These are objects of different types, namely the most powerful pulsar wind nebula; the most powerful supernova remnant; and a shell of 270 light years in diameter blown by multiple stars, and supernovae – a so-called superbubble.
The discovery is announced in the latest edition of the scientific journal, Science, in a research paper titled: The exceptionally powerful TeV ƴ-ray emitters in the Large Magellanic Cloud, which was published on Friday, 23 January 2015.
“This is a very important breakthrough for the team,” says Professor Sergio Colafrancesco, DST/NRF SKA Research Chair in the Wits School of Physics. “It paves the way to study external galaxies with very high-E telescopes such as H.E.S.S and then later with the planned Cherenkov Telescope Array (CTA) in Namibia. It will lead us to re-examine galaxy evolution and answer questions such as how high-E particles can affect the evolution of cosmic structures in the universe, principally galaxies, and the life cycles of matter in galaxies,” he adds.
Very high-energy gamma rays are the best tracers of cosmic accelerators such as supernova remnants and pulsar wind nebulae – end-products of massive stars. There, charged particles are accelerated to extreme velocities. When these particles encounter light or gas in and around the cosmic accelerators, they emit gamma rays. Very high-energy gamma rays can be measured on Earth by observing the Cherenkov light emitted from the particle showers produced by incident gamma rays high up in the atmosphere using large telescopes with fast cameras.
The Large Magellanic Cloud (LMC) is a dwarf satellite galaxy of our Milky Way, located about 170.000 light years away and showing us its face. New, massive stars are formed at a high rate in the LMC, and it harbors numerous massive stellar clusters. The LMC’s supernova rate relative to its stellar mass is five times that of our Galaxy. The youngest supernova remnant in the local group of galaxies, SN 1987A, is also a member of the LMC. Therefore, the H.E.S.S. scientists dedicated significant observation to searching for very high-energy gamma rays from this cosmic object.
For a total of 210 hours, H.E.S.S. has observed the largest star-forming region within the LMC called Tarantula Nebula. For the first time in a galaxy outside the Milky Way, individual sources of very high-energy gamma rays could be resolved: three extremely energetic objects of different types.
The so-called superbubble 30 Dor C is the largest known X-ray-emitting shell and appears to have been created by several supernovae and strong stellar winds. Superbubbles are broadly discussed as (complementary or alternative to individual supernova remnants) factories where the galactic cosmic rays are produced. The H.E.S.S. results demonstrate that the bubble is a source of, and filled by, highly energetic particles. The superbubble represents a new class of sources in the very high-energy regime.
Pulsars are highly magnetized, fast rotating neutron stars that emit a wind of ultra-relativistic particles forming a nebula. The most famous one is the Crab Nebula, one of the brightest sources in the high-energy gamma-ray sky. The pulsar PSR J0537−6910 driving the wind nebula N 157B discovered by the H.E.S.S. telescopes in the LMC is in many respects a twin of the very powerful Crab pulsar in our own Galaxy. However, its pulsar wind nebula N 157B outshines the Crab Nebula by an order of magnitude, in very high-energy gamma rays. Reasons are the lower magnetic field in N 157B and the intense starlight from neighboring star-forming regions, which both promote the generation of high-energy gamma rays.
The supernova remnant N 132D, known as a bright object in the radio and infrared bands, appears to be one of the oldest – and strongest – supernova remnants still glowing in very high-energy gamma rays. Between 2500 and 6000 years old – an age where models predict that the supernova explosion front has slowed down and it ought no longer to be efficiently accelerating particles – it still outshines the strongest supernova remnants in our Galaxy. The observations confirm suspicions raised by other H.E.S.S. observations, that supernova remnants can be much more luminous than thought before.
Observed at the limits of detectability, and partially overlapping with each other, these new sources challenged the H.E.S.S. scientists. The discoveries were only possible due to the development of advanced methods of interpreting the Cherenkov images captured by the telescopes, improving in particular the precision with which gamma-ray directions can be determined.
Indeed, the new H.E.S.S. II 28 m telescope will boost the performance of the H.E.S.S. telescope system, and in the more distant future the planned Cherenkov Telescope Array (CTA) will provide even deeper and higher-resolution gamma-ray images of the LMC – in the plans for science with CTA, the satellite galaxy is already identified as a “Key Science Project” deserving special attention.
· The H.E.S.S. telescope is operated by an international collaboration of scientists with a strong involvement by South African universities, in particular Wits University, North West University, and the Universities of the Free State and Johannesburg. Wits physicists are particularly involved in data analysis techniques, the development of theoretical interpretation tools of both extragalactic and galactic sources, and in the operational shifts at the telescope location in Namibia.
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Dell ups the ante for Data Centre
At Dell Technologies World in Las Vegas this week, the focus fell heavily on advances in data storage and digital transformation.
Dell Technologies this week launched several new Dell EMC storage and server products designed to power up the Modern Data Centre, addressing a wide range of traditional and emerging data centre workloads to help customers drive better business outcomes.
The products were launched at Dell Technologies World in Las Vegas, at a time when organisations race to capitalise on the benefits of emerging technologies ahead of their competitors. According to a recent ESG global survey commissioned by Dell EMC and Intel of 4,000 IT decision-makers, 81% agree if they do not embrace IT Transformation, their organisations no longer will be competitive in their markets.
“The Modern Data Centre is the proving ground for our customers to gain a digital advantage over their competition and achieve better business outcomes,” said Jeff Clarke, Dell vice chairman for products and operations. “Dell EMC is delivering the Modern Data Centre innovations that our customers require, with new solutions that are engineered using future-proof technology to take on the data centre challenges of today and to support the next big thing that our customers are imagining for tomorrow.”
Dell provided the following information on new products and services:
Dell EMC PowerMax
Dell EMC’s PowerMax, the future of enterprise-class storage, is architected with end-to- end NVMe and a built-in, real-time machine learning engine. Building on the legendary architecture and capabilities of Dell EMC’s flagship storage system, PowerMax is the world’s fastest storage array, delivering up to 10M IOPS and 50% better response times – 2x faster than the nearest competitor.
Architected with end-to-end NVMe to support NVMe-over-Fabrics and high-speed, low- latency Storage Class Memory (SCM), PowerMax is not only fast, smart and efficient, but also engineered to handle the world’s most demanding application workloads.
In addition, the PowerMax OS includes a machine learning engine, which makes autonomous storage a reality, leveraging predictive analytics and pattern recognition to maximize performance with no management overhead. Built-in machine learning is the only cost-effective way to leverage SCM. Dell EMC is also the only company that can provide this level of storage software intelligence – currently analyzing 425 billion data sets in real time across its high-end All-Flash customer base.
PowerMax also includes inline deduplication and enhanced compression providing up to 5:1 data reduction, while delivering industry-leading security, protection and resiliency. It achieves greater than “six nines” availability to help ensure zero downtime of business-critical applications.
Storage solutions are increasingly being consumed within converged infrastructure, namely the Dell EMC VxBlock System 1000. As the industry’s leading provider of converged infrastructure systems, Dell EMC offers expanded options for VxBlock 1000 customers who can benefit from fast, smart and efficient storage with new support for PowerMax with end-to-end NVMe and XtremIO X2 All-Flash arrays. This means that the VxBlock system breaks the physical boundaries of traditional CI and offers enterprises even greater simplicity and flexibility to help accelerate their IT and digital transformation efforts.
To speed implementation of PowerMax or VxBlock in their environment, customers can take advantage of Dell EMC ProDeploy Plus services for up to 66% faster deployment and up to 49% fewer technical support calls. Customers can also choose ProSupport Plus for consistent best-in-class support delivered across their environment and up to 75% faster service request response time.
Dell EMC XtremIO Replication
XtremIO X2 All-Flash arrays gain major updates with the new XIOS 6.1 operating system, including delivering the industry’s most efficient replication across a wide area network (WAN). X2 metadata-aware native replication is highly efficient and provides an added level of data protection for application workloads. XtremIO replication sends only unique data to the remote site to minimize bandwidth requirements by 75% or more, enabling potential network cost savings. XtremIO replication requires up to 38% less storage space15 at disaster recovery sites and operates with predictable performance to achieve recovery point objectives of 30 seconds.
Dell Technologies also introduced a new Dell EMC X2 entry model for customers, at up to 55% lower cost than the previous generation. Designed with XtremIO’s unique metadata-centric architecture with full data services including inline data reduction (in-memory space-efficient copies, deduplication and compression), XtremIO can also achieve over “five nines” availability, offering customers enterprise-grade capabilities that start at midrange prices.
Dell EMC PowerEdge MX
Dell EMC will preview PowerEdge MX, a new modular infrastructure solution for the modern data centre. Designed with Dell EMC’s kinetic infrastructure, PowerEdge MX will enable customers to flexibly configure and optimise their IT infrastructure for new and emerging workloads.
Available in the second half of 2018, PowerEdge MX will bring new levels of flexibility to IT, ideal for dense virtualisation, software-defined storage and networking, network functions virtualisation (NFV) and big data analytic environments.
Dell EMC’s Modern Data Centre solutions PowerMax and XtremIO X2 with native replication, as well as VxBlock System 1000 with XtremIO X2, are available now. VxBlock System 1000 with PowerMax support will launch mid-year. Dell EMC PowerEdge MX has planned global availability for the second half of 2018.
MediaTek and Microsoft join forces for Azure chip
MediaTek has announced a collaboration with Microsoft to deliver the first Azure Sphere chip, the MT3620, designed to drive IoT with built-in security and connectivity.
Azure Sphere is a solution for creating highly-secured, connected devices powered by a Microcontroller Unit (MCU).
MediaTek and Microsoft have worked together to develop a specialised chipset with a Wi-Fi connected controller built around a processor designed to run Azure Sphere’s IoT operating system. It also includes built-in support for Microsoft’s latest security protocols. These chipsets will be sold as part of the Azure Sphere solution, enabling customers across a broad set of industries to connect MCU-powered products and devices.
“MediaTek has a long history of working with Microsoft on specific SoC designs that meet demanding connectivity needs,” said Jerry Yu, MediaTek corporate vice president and general manager of the Intelligent Devices Business Group. “On top of our close ties with Microsoft and design expertise, Microsoft had a vision we also believed in. Bringing trust and security into IoT solutions from chip to cloud, to make connected devices practical to sell and manage for businesses and consumers.”
Significant drops in the cost of connectivity mean that billions of MCU-powered devices, from household appliances and health monitors to children’s toys and industrial equipment, will be connected. With more points of connectivity come more points of possible vulnerability, which mean companies and individuals will only take advantage of convenient connected devices if they believe their devices, data and cloud are secure.
“Today, computing is more powerful and ubiquitous from the cloud to the edge. In the next decade we’ll see the democratization of connectivity to billions of devices,” said Galen Hunt, managing director of Azure Sphere at Microsoft.
“Azure Sphere brings together the best of Microsoft’s expertise in cloud, software, and silicon— resulting in a unique approach to security that starts in the silicon and extends to the cloud. MediaTek has worked in close collaboration with us on the silicon aspect of our solution, and we are pleased to share in this announcement of the MT3620, the first Azure Sphere certified chip. What we are delivering together will be the foundation for a new generation of secure intelligent edge devices and solutions.”
MediaTek is currently sampling chips with lead customers and will have broad product availability by Q3 of 2018. For details visit MediaTek’s solution.