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News Article | April 25, 2017
Site: www.sciencedaily.com

The incidence of cardiovascular diseases in Sweden has decreased sharply since the late 1990s. These are the findings of a study from Sahlgrenska Academy which included almost three million adult Swedes. In relative terms, the biggest winners are persons with type 1 and type 2 diabetes. "This is a huge improvement and a testament to the improvements in diabetes and cardiovascular care throughout Sweden," says Aidin Rawshani, medical doctor and doctoral student in molecular and clinical medicine. The study, which was published in The New England Journal of Medicine, shows that the incidence of cardiovascular diseases and deaths among individuals with diabetes in Sweden dropped significantly between 1998 and 2014. The population in general exhibited the same trend, albeit to a smaller extent. Among persons with type 1 diabetes, with an average age of 35 years, the incidence pf cardiovascular disease was reduced by 40 per cent during the period in question. In the control group of persons of similar age but without diabetes, the decrease was 10 per cent. Among individuals with type 2 diabetes, with an average age of 65 years, the incidence of cardiovascular disease decreased by 50 per cent. Among control persons of similar age without diabetes, the decrease was 30 per cent. "We were surprised by the results, specially for persons with diabetes. Some smaller studies in the past have indicated that numbers were improving, but nothing of this magnitude," says Aidin Rawshani. In total, approximately 2.96 million individuals were studied, of which 37,000 had type 1 diabetes and 460,000 had type 2 diabetes. The results of the study are based on linked processing of data from the National Diabetes Register, the Cause of Death Register and the part of the Patient register that concerns inpatient care. In addition to matching by age and gender, the groups that were compared were also matched geographically using register data from LISA (the longitudinal integration database for health insurance and labour market studies). The deaths that took place in the groups during the study period were almost exclusively related to cardiovascular disease. Individuals with diabetes have previously shown to suffer a risk of cardiovascular disease and early death that was between two and five times as high as in the general population. "One of the main findings of the study is that both deaths and the incidence of cardiovascular disease is decreasing in the population, both in matching control groups and among persons with type 1 and type 2 diabetes. One paradoxical finding is that individuals with type 2 diabetes have seen a smaller improvement over time regarding deaths compared to the controls, while persons with type 1 diabetes have made an equal improvement to the controls," notes Aidin Rawshani. The positive trends that have been observed in the study are most likely due to an increased use of preventative cardiovascular medicines, advances in the revascularisation of atherosclerotic disease and improved use of instruments for continual blood sugar monitoring, and the fact that Swedish diabetes care has generally worked well with good treatment guidelines and quality assurance efforts. "Out study and analysis does not include explanations of these trends, but we believe that it is a matter of better control of risk factors, better education patients, better integrated treatment systems for individuals with chronic illnesses and individual care for persons with diabetes. There is often an entire team working with a patient, ensuring that their needs are met," says Aidin Rawshani.


News Article | April 18, 2017
Site: www.sciencedaily.com

Scientists hope to take advantage of LISA Pathfinder's record-breaking sensitivity to acceleration to map out the distribution of tiny dust particles shed by asteroids and comets far from Earth.


News Article | April 25, 2017
Site: www.eurekalert.org

The incidence of cardiovascular diseases in Sweden has decreased sharply since the late 1990s. These are the findings of a study from Sahlgrenska Academy which included almost three million adult Swedes. In relative terms, the biggest winners are persons with type 1 and type 2 diabetes. "This is a huge improvement and a testament to the improvements in diabetes and cardiovascular care throughout Sweden," says Aidin Rawshani, medical doctor and doctoral student in molecular and clinical medicine. The study, which was published in The New England Journal of Medicine, shows that the incidence of cardiovascular diseases and deaths among individuals with diabetes in Sweden dropped significantly between 1998 and 2014. The population in general exhibited the same trend, albeit to a smaller extent. Among persons with type 1 diabetes, with an average age of 35 years, the incidence pf cardiovascular disease was reduced by 40 per cent during the period in question. In the control group of persons of similar age but without diabetes, the decrease was 10 per cent. Among individuals with type 2 diabetes, with an average age of 65 years, the incidence of cardiovascular disease decreased by 50 per cent. Among control persons of similar age without diabetes, the decrease was 30 per cent. "We were surprised by the results, specially for persons with diabetes. Some smaller studies in the past have indicated that numbers were improving, but nothing of this magnitude," says Aidin Rawshani. In total, approximately 2.96 million individuals were studied, of which 37,000 had type 1 diabetes and 460,000 had type 2 diabetes. The results of the study are based on linked processing of data from the National Diabetes Register, the Cause of Death Register and the part of the Patient register that concerns inpatient care. In addition to matching by age and gender, the groups that were compared were also matched geographically using register data from LISA (the longitudinal integration database for health insurance and labour market studies). The deaths that took place in the groups during the study period were almost exclusively related to cardiovascular disease. Individuals with diabetes have previously shown to suffer a risk of cardiovascular disease and early death that was between two and five times as high as in the general population. "One of the main findings of the study is that both deaths and the incidence of cardiovascular disease is decreasing in the population, both in matching control groups and among persons with type 1 and type 2 diabetes. One paradoxical finding is that individuals with type 2 diabetes have seen a smaller improvement over time regarding deaths compared to the controls, while persons with type 1 diabetes have made an equal improvement to the controls," notes Aidin Rawshani. The positive trends that have been observed in the study are most likely due to an increased use of preventative cardiovascular medicines, advances in the revascularisation of atherosclerotic disease and improved use of instruments for continual blood sugar monitoring, and the fact that Swedish diabetes care has generally worked well with good treatment guidelines and quality assurance efforts. "Out study and analysis does not include explanations of these trends, but we believe that it is a matter of better control of risk factors, better education patients, better integrated treatment systems for individuals with chronic illnesses and individual care for persons with diabetes. There is often an entire team working with a patient, ensuring that their needs are met," says Aidin Rawshani.


News Article | March 1, 2017
Site: www.businesswire.com

THERADIAG (Paris:ALTER) (ISIN : FR0004197747, Mnémonique : ALTER), société spécialisée dans le diagnostic in vitro et le théranostic annonce aujourd’hui son chiffre d’affaires et ses résultats annuels consolidés pour l’exercice clos au 31 décembre 2016 et arrêtés par le Conseil d’administration du 28 février 2017. « Les partenariats signés en 2015 avec des acteurs internationaux majeurs de la pharma et du diagnostic ont entrainé, comme attendu, une forte croissance de notre activité dès l’exercice 2016 (+19%). Cette tendance sera renforcée en 2017 par la poursuite de notre développement aux Etats-Unis avec Miraca Life Sciences et notamment dans le cadre de l’accord Janssen. Le lancement en Europe des produits co-developpés avec notre partenaire chinois HOB Biotech contribuera également à cette évolution très positive. L’accélération significative de la croissance du chiffre d’affaires a permis la réduction de plus d’un tiers de notre perte opérationnelle au cours de l’exercice 2016 et nous permet d’envisager l’atteinte de l’équilibre financier à court terme », commente Michel Finance, Directeur Général de Theradiag. Le chiffre d’affaires annuel de la business unit théranostic atteint désormais 4 millions d’euros contre 2,3 millions d’euros sur l’exercice précédent, soit une croissance de 74% pour représenter 45% du chiffre d’affaires total. Il intègre les ventes résultant de ventes directes aux hôpitaux et aux laboratoires mais également, et pour une part significative en 2016, celles issues des différents partenariats avec Miraca Life Sciences, Janssen, UCB, et Hospira/Pfizer. Le développement des ventes avec Miraca Life Sciences sur le marché américain devrait être un facteur important de croissance pour les trimestres à venir et avoir un impact favorable sur l’année 2017. Au cours de l’exercice 2016, les coûts directs de recherche et développement se sont élevés, hors subvention, à 1,4 millions d’euros et ont été axés principalement sur la poursuite du développement des kits LISA TRACKER® et les projets menés sur la plateforme technologique microARN. Par ailleurs, en août 2016, Janssen Biotech Inc. a lancé le programme Janssen 2Inform destiné à offrir gratuitement des tests de monitoring pour aider les professionnels de santé à mieux utiliser le Remicade® dans le traitement des patients atteints de maladies inflammatoires chroniques de l’intestin (MICI). Grâce au partenariat signé entre Miraca Life Sciences et Theradiag, ce sont les tests de monitoring de Theradiag, que Miraca Life Sciences fournit sous le nom InformTxTM, qui sont proposés dans le programme Janssen 2Inform. Theradiag vend les matières nécessaires et perçoit des royalties sur les ventes réalisées par Miraca Life Sciences aux États-Unis. L’intérêt de la communauté scientifique pour le monitoring des biothérapies a été confirmé lors du 11ème congrès ECCO (European Crohn’s and Colitis Organisation) avec un nombre toujours plus important de données sur le monitoring des biothérapies présenté lors de ce congrès avec plus de 25 présentations orales et une quarantaine de posters. Ce chiffre a doublé en 2016, validant l’approche théranostique de Theradiag. Une quinzaine de présentations et posters étaient notamment basés sur les tests de monitoring Lisa Tracker® de Theradiag. Prestizia a été sélectionnée par le programme Eurostars-2, pour le soutien financier de son projet collaboratif PIONEER mené par sa plateforme de biologie moléculaire Prestizia et ses partenaires coréens du sud, l’Asan Medical Center et la société CbsBioscience. Le projet PIONEER est destiné à développer deux tests basés sur des biomarqueurs microARN circulants et des ARN messagers tissulaires dans le cancer du rectum. A propos de Theradiag Forte de son expertise dans la distribution, le développement et la fabrication de tests de diagnostic in vitro, Theradiag innove et développe des tests de théranostic (alliance du traitement et du diagnostic), qui mesurent l’efficacité des biothérapies dans le traitement des maladies auto-immunes, du cancer et du SIDA. Theradiag participe ainsi au développement de la « médecine personnalisée », favorisant l’individualisation des traitements, la mesure de leur efficacité et la prévention des résistances médicamenteuses. Theradiag commercialise la gamme Lisa Tracker, marquée CE, une solution complète de diagnostic multiparamétrique pour la prise en charge des patients atteints de maladies auto-immunes et traités par biothérapies. Via sa filiale Prestizia, Theradiag développe également de nouveaux marqueurs de diagnostic grâce à la plateforme microARN, pour la détection et le suivi du cancer du rectum et du VIH/SIDA. La société est basée à Marne-la-Vallée et Montpellier et compte plus de 75 collaborateurs.


News Article | February 15, 2017
Site: www.spie.org

From the SPIE Photonics West Show Daily : Three plenary speakers at LASE 2017 discussed the LIGO discovery of gravitational waves in space, laser-based direct-write methods, and high-power EUV light sources for lithography. For more than a quarter of a century, Karsten Danzmann has dedicated his career to developing technology that could expand our understanding of the universe by detecting gravitational waves emanating from exotic objects in space. On September 14, 2015, the Laser Interferometer Gravitational-wave Observatory (LIGO) finally did just that. For the first time, US LIGO detectors in Livingston, LA, and Hanford, WA, heard the first "peep" from an event in the distant universe — in this case the collision of two black holes. The event confirmed a major prediction of Albert Einstein's 1915 general theory of relativity and opened a new window into the cosmos. It was such a major breakthrough that it took several days for the LIGO team to accept that it might actually be real, according to Danzmann, director of the Max Planck Institute for Gravitational Physics, a member of the LIGO Scientific Collaboration. And it was another five months before they made their findings public. "I've been chasing this for 27 years, and when it finally happened it was unbelievable," said Danzmann, who noted that a second, similar event, the detection of gravitational waves produced by two black holes colliding 1.4 billion light years away, was captured in June 2016 at the same two observatories. "We've been looking at the universe with our eyes for thousands of years, and we know it looks very different depending on whether we look at it with visible light, infrared light, gamma rays, xrays, ... but we haven't been able to hear it. And suddenly now we can. And we have hope that the dark side of the universe, which makes up 99% of the universe, is now accessible to us." During the LASE plenary session at SPIE Photonics West 2017 in February, Danzmann's enthusiasm was contagious as he described the developments leading up to that historic moment, from the physics and technology to the thousands of people involved worldwide for decades (the first published paper, in Physics Review Letters, listed 1004 authors from 133 institutions). For Danzmann, one of the key turning points came when Advanced LIGO, a $200 million upgrade to LIGO, was unveiled in mid-2015. With the upgrade, which took five years to complete, the observatories are now 10 times more sensitive than their predecessors, thanks to advances in the optical layout, new high-power (165W) stabilized laser systems, advanced mirror suspension, and improved pre-isolation for detecting very low frequencies, according to Danzmann. "The upgrade to Advanced LIGO was drastic," Danzmann said. "The building is still the same, and the stainless steel of vacuum tubes are the same, but everything else has changed." Danzmann is equally excited about a more recent development: LISA Pathfinder, a satellite mission launched in December 2015 whose payload includes the first laser interferometer in space. "On the ground we are listening to the high frequencies of the universe, but if we want to listen to low frequencies, we have to go into space," said Danzmann, who is co-principal investigator on the LISA technology package. "Some of the most interesting things in the universe are supermassive black holes. When galaxies collide, which happens all the time, these super black holes merge and emit a huge signal, and that is what we want to listen to in space." Another LASE plenary talk featured an overview of the current state-of-the-art in using laser-based direct-write (LDW) methods to print hybrid electronics. The talk was given by Alberto Pique, acting head of the Materials and Sensor Branch of the Materials Science Division at the US Naval Research Laboratory. "The goal is very simple: can we go from a design to a printed part that is not faithful in a structural sense but in a functional sense?" Pique posited. "To do that, we need a substrate, we need to wire it up, place the devices, then connect the wires and devices. If you do it right, you end up with a functional circuit." This is where additive manufacturing (AM) comes in. AM is considered a game changer for design and fabrication of 3D parts by reducing the number of steps from concept to part, while direct-write processes make it possible to fabricate custom electronics in less time and at lower cost than other techniques. Combining the two paves the way for more efficient and cost-effective printing of hybrid electronics. The ability of LDW to deposit functional materials over a wide viscosity range onto many diverse surfaces makes it unique among direct write processes, Pique noted. For example, when manufacturing inkjet nozzles, "you have to be careful about the material you put on the nozzle and you have to worry about the nature of the fluid. But when you use the LDW forward transfer technique, the nature of material is not that critical." Advances in lasers, materials, and positioning have spurred the development of LDW in AM, he added. In particular, the availability of high-repetition rate solid-state UV lasers with stable, moderate energies has allowed LDW to deposit materials rapidly in all three dimensions. By comparison, low-rep rate UV lasers with more uniform beam profiles have enabled printing larger area voxels, which also speeds up the LDW process. "Over the years, we have shown that with LDW we can both add and remove material, and this gives the laser technique an edge (over other direct-write techniques) because you can do two things with the same set up," Pique said. "The same system performs both additive and subtractive processes." In the final LASE plenary talk, Hakaru Mizoguchi, executive vice president of Gigaphoton, provided an update on the company's efforts to develop high-power EUV light sources for high-volume manufacturing (HVM) lithography. In July 2016, Gigaphoton demonstrated 250W light output at 4% conversion efficiency with a laser-produced plasma (LPP) light source prototype for EUV scanners. Since then, Gigaphoton has continued to test and refine its EUV light sources, with a goal of eventually reaching 500W, according to Mizoguchi. Photolithography equipment manufacturers are keen for a 250W power EUV source to deliver the kind of wafer productivity throughput their customers demand. To achieve these powers, Gigaphoton uses a dual-laser "priming" pulse from a yv04 (vanadate) laser ahead of a nanosecond-duration carbon dioxide blast, plus sub 20 μm micro droplet supply technology, proprietary energy control technology, and magnetic field-enabled debris mitigation technology. In anticipation of introducing these systems to the commercial market, the company is preparing to move into a new headquarters in Japan that doubles its office space and provides 1.5 times the production space, Mizoguchi noted. Symposium chairs for LASE 2017 were SPIE Fellows Koji Sugioka of RIKEN (Japan) and Reinhart Poprawe of Fraunhofer-Institut für Lasertechnik (Germany). Cochairs were SPIE Fellow Yongfeng Lu of University of Nebraska, Lincoln (USA), and Guido Hennig of Daetwyler Graphics (Switzerland). Photonics West 2017, 28 January through 2 February at the Moscone Center in San Francisco, CA (USA), encompassed more than 4700 presentations on light-based technologies across more than 95 conferences. It was also the venue for dozens of technical courses for professional development, the Prism Awards for Photonics Innovation, the SPIE Startup Challenge, a two-day job fair, two major exhibitions, and a diverse business program with more than 25 events. SPIE Photonics West 2018 will run 27 January through 1 February at Moscone Center.


News Article | February 18, 2017
Site: www.bbc.co.uk

The long-planned LISA space mission to detect gravitational waves looks as though it will be green lit shortly. Scientists working on a demonstration of its key measurement technologies say they have just beaten the sensitivity performance that will be required. The European Space Agency (Esa), which will operate the billion-euro mission, is now expected to "select" the project, perhaps as early as June. The LISA venture intends to emulate the success of ground-based detectors. These have already witnessed the warping of space-time that occurs when black holes 10-20 times the mass of the Sun collide about a billion light-years from Earth. LISA, however, aims to detect the coming together of truly gargantuan black holes, millions of times the mass of the Sun, all the way out to the edge of the observable Universe. Researchers will use this information to trace the evolution of the cosmos, from its earliest structures to the complex web of galaxies we see around us today. The performance success of the measurement demonstration was announced here in Boston at the annual meeting of the American Association for the Advancement of Science (AAAS). It occurred on Esa's LISA "Pathfinder" (LPF) spacecraft that has been flying for just over a year. This probe is trialling parts of the laser interferometer that will eventually be used to detect passing gravitational waves. When Pathfinder's instrumentation was set running it was hoped it would get within a factor of 10 of the sensitivity that would ultimately be needed by the LISA mission, proper. In the event, LPF not only matched this mark, but went on to exceed it after 12 months of experimentation. "You can do the full science of LISA just based on what LPF has got. And that's thrilling; it really is beyond our dreams," Prof Stefano Vitale, Pathfinder's principal investigator, told BBC News. Gravitational waves - Ripples in the fabric of space-time The first detection of gravitational waves at the US LIGO laboratories in late 2015 has been described as one of the most important physics breakthroughs in decades. Being able to sense the subtle warping of space-time that occurs as a result of cataclysmic events offers a completely new way to study the Universe, one that does not depend on traditional telescope technology. Rather than trying to see the light from far-off events, scientists would instead "listen" to the vibrations these events produce in the very fabric of the cosmos. LIGO achieved its success by discerning the tiny perturbations in laser light that was bounced between super-still mirrors suspended in kilometres' long, vacuum tunnels. LISA would do something very similar, except its lasers would bounce between free-floating gold-platinum blocks carried on three identical spacecraft separated by 2.5 million km. In both cases, the demand is to characterise fantastically small accelerations in the measurement apparatus as it is squeezed and stretched by the passing gravitational waves. For LISA the projected standard is to characterise movements down below the femto-g level - a millionth of a billionth of the acceleration a falling apple experiences at Earth's surface; and to do that over periods of minutes to hours. LISA Pathfinder has just succeeded in achieving sub-femto sensitivity over timescales of half a day. Getting stability at the lowest frequencies is very important. "The lower the frequency to which you go, the bigger are the bodies that generate gravitational waves; the more intense are the gravitational waves; and the more far away are the bodies. So, the lower the frequencies, the deeper into the Universe you go," explained Prof Vitale, who is affiliated to Italian the Institute for Nuclear Physics and University of Trento. To be clear, LPF cannot itself detect gravitational waves because the "arm length" of the system has been shrunk down from 2.5 million km to just 38 cm - to be able to fit inside a single demonstration spacecraft - but it augurs well for the full system. Esa recently issued a call for proposals to fly a gravitational science mission in 2034. The BBC understands the agency received only one submission - from the LISA Consortium. This is unusual. Normally such calls attract a number of submissions from several groups all with different ideas for a mission. But in this instance, it is maybe not so surprising given that the LISA concept has been investigated for more than two decades. Prof Karsten Danzmann, co-PI on LPF and the lead proposer of LISA, hopes a way can be found to fly his consortium's three-spacecraft detection system earlier than 2034, perhaps as early as 2029. But that requires sufficient money being available. "The launch date is only programatically dominated, not technically," Prof Danzmann told BBC News. "And with all the interest in gravitational waves building up right now, ways will be found to fly almost simultaneously with Athena (Europe's next-generation X-ray telescope slated to launch in 2028). "This would make perfect sense because we can tell the X-ray guys where to look, because we get the alert of any bright (black hole) merger immediately, and then we can tell them, 'look in the next hour and you'll see an X-ray flash'." "That would be tremendously exciting to do multi-messenger astronomy with LISA and Athena at the same time." LISA could be selected as a confirmed project at Esa's Science Programme Committee in June. There would then be a technical review followed by parallel industrial studies to assess the best, most cost-effective way to construct the mission. Agreement will also be sought with the Americans to bring them onboard. They are likely to contribute about $300-400m of the overall cost in the form of components, such as the lasers that will be fired between LISA's trio of spacecraft. The LPF demonstration experiments are due to end in May, or June at the latest. Jonathan.Amos-INTERNET@bbc.co.uk and follow me on Twitter: @BBCAmos


News Article | February 15, 2017
Site: cerncourier.com

From the extreme dynamics of black holes to the beginning of the universe itself, the detection of gravitational waves has opened a profound new vista on nature. L’une des plus grandes découvertes scientifiques de notre siècle a eu lieu le 14 septembre 2015, lorsqu’un train d’ondes gravitationnelles issu de la collision de deux trous noirs, à 1,4 milliard d’années-lumière de la Terre, est passé à travers l’expérience aLIGO. Cet événement a marqué la fin d’une quête qui avait duré un demi-siècle, et l’entrée dans la nouvelle ère de l’astronomie des ondes gravitationnelles. La capacité que nous avons à présent d’observer l’Univers à l’aide des ondes gravitationnelles remettra en question notre connaissance actuelle de la gravité et de la physique fondamentale, car elle pourrait dévoiler la nature des objets les plus extrêmes que nous connaissons et peut-être faire la lumière sur l’origine de l’Univers lui-même. Et ce n’est là qu’un début. One of the greatest scientific discoveries of the century took place on 14 September 2015. At 09.50 UTC on that day, a train of gravitational waves launched by two colliding black holes 1.4 billion light-years away passed by the Advanced Laser Interferometer Gravitational-wave Observatory (aLIGO) in Louisiana, US, causing a fractional variation in the distance between the mirrors of about one part in 1021. Just 7 ms later, the same event – dubbed GW150914 – was picked up by the twin aLIGO detector in Washington 3000 km away (figure 1). A second black-hole coalescence was observed on 26 December 2015 (GW151226) and a third candidate event was also recorded, although its statistical significance was not high enough to claim a detection. A search that had gone on for half a century had finally met with success, ushering in the new era of gravitational-wave astronomy. Black holes are the simplest physical objects in the universe: they are made purely from warped space and time and are fully described by their mass and intrinsic rotation, or spin. The gravitational-wave train emitted by coalescing binary black holes comprises three main stages: a long “inspiral” phase, where gravitational waves slowly and steadily drain the energy and angular momentum from the orbiting black-hole pair; the “plunge and merger”, where black holes move at almost the speed of light and then coalesce into the newly formed black hole; and the “ringdown” stage during which the remnant black hole settles to a stationary configuration (figure 2). Each dynamical stage contains fingerprints of the astrophysical source, which can be identified by first tracking the phase and amplitude of the gravitational-wave train and then by comparing it with highly accurate predictions from general relativity. aLIGO employs waveform models built by combining analytical and numerical relativity. The long, early inspiral phase, characterised by a weak gravitational field and low velocities, is well described by the post-Newtonian formalism (which expands the Einstein field equation and the gravitational radiation in powers of v/c, but loses accuracy as the two bodies come closer and closer). Numerical relativity provides the most accurate solution for the last stages of inspiral, plunge, merger and ringdown, but such models are time-consuming to produce – the state-of-the-art code of the Simulating eXtreme Spacetimes collaboration took three weeks and 20,000 CPU hours to compute the gravitational waveform for the event GW150914 and three months and 70,000 CPU hours for GW151226. A few hundred thousand different waveforms were used as templates by aLIGO during the first observing run, covering compact binaries with total masses 2–100 times that of the Sun and mass ratios up to 1:99. Novel approaches to the two-body problem that extend post-Newtonian theory into the strong-field regime and combine it with numerical relativity had to be developed to provide aLIGO with accurate and efficient waveform models, which were based on several decades of steady work in general relativity (figure 3). Further theoretical work will be needed to deal with more sensitive searches in the future if we want to take full advantage of the discovery potential of gravitational-wave astronomy. The two gravitational-wave signals observed by aLIGO have different morphologies that reveal quite distinct binary black-hole sources. GW150914 is thought to be composed of two stellar black holes with masses 36 M and 29 M , which formed a black hole of about 62 M rotating at almost 70% of its maximal rotation speed, while GW151226 had lower black-hole masses (of about 14 M and 8 M ) and merged in a 21 M black-hole remnant. Although the binary’s individual masses for GW151226 have larger uncertainties compared with GW150914 (since the former happened at a higher frequency where aLIGO sensitivity degrades), the analysis ruled out the possibility that the lower-mass object in GW151226 was a neutron star. A follow-up analysis also revealed that the individual black holes had spins less than 70% of the maximal value, and that at least one of the black holes in GW151226 was rotating at 20% of its maximal value or faster. Finally, the aLIGO data show that the binaries that produced GW150914 and GW151226 were at comparable distances from the Earth and that the peak of the gravitational-wave luminosity was about 3 × 1056 erg/sec, making them by far the most luminous transient events in the universe. Owing to the signal’s length and the particular orientation of the binary plane with respect to the aLIGO detectors, no information about the spin precession of the system could be extracted. It has therefore not yet been possible to determine the precise astrophysical production route for these objects. Whereas the predictions for the rate of binary black-hole mergers from astrophysical-formation mechanisms traditionally vary by several orders of magnitude, the aLIGO detections so far have already established the rate to be somewhat on the high side of the range predicted by astrophysical models at 9–240 per Gpc3 per year. Larger black-hole masses and higher coalescence rates raise the interesting possibility that a stochastic background of gravitational waves composed of unresolved signals from binary black-hole mergers could be observed when aLIGO reaches its design sensitivity in 2019. The sky localisation of GW150914 and GW151226, which is mainly determined by recording the time delays of the signals arriving at the interferometers, extended over several hundred square degrees. This can be compared with the 0.2 square degrees covered by the full Moon as seen from the Earth, and makes it very hard to search for an electromagnetic counterpart to black-hole mergers. Nevertheless, the aLIGO results kicked off the first campaign for possible electromagnetic counterparts of gravitational-wave signals, involving almost 20 astronomical facilities spanning the gamma-ray, X-ray, optical, infrared and radio regions of the spectrum. No convincing evidence of electromagnetic signals emitted by GW150914 and GW151226 was found, in line with expectations from standard astrophysical scenarios. Deviations from the standard scenario may arise if one considers dark electromagnetic sectors, spinning black holes with strong magnetic fields that need to be sustained until merger, and black holes surrounded by clouds of axions (see "Linking waves to particles"). aLIGO’s observations allow us to test general relativity in the so-far-unexplored, highly dynamical and strong-field gravity regime. As the two black holes that emitted GW150914 and GW151226 started to merge, the binary’s orbital period varied considerably and the phase of the gravitational-wave signal changed accordingly. It is possible to obtain an analytical representation of the phase evolution in post-Newtonian theory, in which the coefficients describe a plethora of dynamical and radiative physical effects, and long-term timing observations of binary pulsars have placed precise bounds on the leading-order post-Newtonian coefficients. However, the new aLIGO observations have put the most stringent limits on higher post-Newtonian terms – setting upper bounds as low as 10% for some coefficients (figure 4). It was even possible to investigate potential deviations during the non-perturbative coalescence phase, and again general relativity passed this test without doubt. The first aLIGO observations could neither test the second law of black-hole mechanics, which states that the black-hole entropy cannot decrease, nor the “no-hair” theorem, which says that a black hole is only described by mass and spin, for which we require to extract the mass and spin of the final black hole from the data. But we expect that future, multiple gravitational-wave detections with higher signal-to-noise ratios will shed light on these important theoretical questions. Despite those limitations, aLIGO has provided the most convincing evidence to date that stellar-mass compact objects in our universe with masses larger than roughly five solar masses are described by black holes: that is, by the solutions to the Einstein field equations (see "General relativity at 100"). During its first observation run, lasting from mid-September 2015 to mid-January 2016, aLIGO did not detect gravitational waves from binaries composed of either two neutron stars, or a black hole and a neutron star. Nevertheless, it set the most stringent upper limits on the rates of such processes: 12.6 × 103 and 3.6 × 103 per Gpc3 per year, respectively. The aLIGO rates imply that we expect to detect those binary systems a few years after aLIGO and the French–Italian experiment Virgo reach their design sensitivity. Observing gravitational waves from binaries made up of matter is exciting because it allows us to infer the neutron-star equation of state and also to unveil the possible origin of short-hard gamma-ray bursts (GRBs) – enormous bursts of electromagnetic radiation observed in distant galaxies. Neutron stars are extremely dense objects that form when massive stars run out of nuclear fuel and collapse. The density in the core is expected to be more than 1014 times the density of the Sun, at which the standard structure of nuclear matter breaks down and new phases of matter such as superfluidity and superconductivity may appear. All mass and spin parameters being equal, the gravitational-wave train emitted by a binary containing a neutron star differs from the one emitted by two black holes only in the late inspiral phase, when the neutron star is tidally deformed or disrupted. By tracking the gravitational-wave phase it will be possible to measure the tidal deformability parameter, which contains information about the neutron-star interior, and ultimately to discriminate between some equations of state. The merger of double neutron stars and/or black-hole–neutron-star binaries is currently considered the most likely source of short-hard GRBs, and we expect a plethora of electromagnetic signals from the coalescence of such compact objects that will test the short-hard GRB/binary-merger paradigm. Bursts of gravitational waves lasting for tenths of milliseconds are also produced during the catastrophic final moments of all stars, when the stellar core undergoes a sudden collapse (or supernova explosion) to a neutron star or a black hole. At design sensitivity, aLIGO and Virgo could detect bursts from the core’s “bounce”, provided that the supernova took place in the Milky Way or neighbouring galaxies, with more extreme emission scenarios observable to much further distances. Highly magnetised rotating neutron stars called pulsars are also promising astrophysical sources of gravitational waves. Mountains just a few centimetres in height on the crust of pulsars can cause the variation in time of the pulsar’s quadrupole moment, producing a continuous gravitational-wave train at twice the rotation frequency of the pulsar. The most recent LIGO all-sky searches and targeted observations of known pulsars have already started to invade the parameter space of astrophysical interest, setting new upper limits on the source’s ellipticity, which depends on the neutron-star’s equation of state. Lastly, several physical mechanisms in the early universe could have produced gravitational waves, such as cosmic inflation, first-order phase transitions and vibrations of fundamental and/or cosmic strings. Being that gravitational waves are almost unaffected by matter, they provide us with a pristine snapshot of the source at the time they were produced. Thus, gravitational waves may unveil a period in the history of the universe around its birth that we cannot otherwise access. The first observation run of aLIGO has set the most stringent constraints on the stochastic gravitational-wave background, which is generally expressed by the dimensionless energy density of gravitational waves, of < 1.7 × 10−7. Digging deeper, at design sensitivity aLIGO is expected to reach a value of 10−9, while next-generation detectors such as the Einstein Telescope and the Cosmic Explorer may achieve values as low as 10−13 – just two orders of magnitude above the background predicted by the standard “slow-roll” inflationary scenario. The sensitivity of existing interferometer experiments on Earth will be improved in the next 5–10 years by employing a quantum-optics phenomenon called squeezed light. This will reduce the sky-localisation errors of coalescing binaries, provide a better measurement of tidal effects and the neutron-star equation of state in binary mergers, and enhance our chances of observing gravitational waves from pulsars and supernovae. The ability to identify the source of gravitational waves will also improve over time, as upgraded and new gravitational-wave observatories come online. Furthermore, pulsar signals offer an alternative Pulsar Timing Array (PTA) detection scheme that is currently operating. Gravitational waves passing through pulsars and the Earth would modify the time of arrival of the pulses, and searches for correlated signatures in the pulses’ times of arrival from the most stable known pulsars by PTA projects could detect the stochastic gravitational-wave background from unresolved supermassive binary black-hole inspirals in the 10−9–10−7 Hz frequency region. Results from the North-American NANOGrav, European EPTA and Australian PPTA collaborations have already set interesting upper limits on the astrophysical background, and could achieve a detection in the next five years. The past year has been a milestone for gravitational-wave research in space, with the results of the LISA Pathfinder mission published in June 2016 exceeding all expectations and proving that LISA, planned for 2034, will work successfully (see "Catching a gravitational wave"). LISA would be sensitive to gravitational waves between 10−4–10−2 Hz, thus detecting sources different from the ones observed on the Earth such as supermassive binary black holes, extreme mass-ratio inspirals, and the astrophysical stochastic background from white-dwarf binaries in our galaxy. In the meantime, a new ground facility to be built in 10–15 years – such as the Einstein Telescope in Europe and the Cosmic Explorer in the US – will be required to maximise the scientific potential of gravitational-wave physics and astrophysics. These future detectors will allow such high sensitivity to binary coalescences that we can probe binary black holes in all our universe, enabling the most exquisite tests of general relativity in the highly dynamical, strong-field regime. That will challenge our current knowledge of gravity, fundamental and nuclear physics, unveiling the nature of the most extreme objects in our universe.


News Article | February 15, 2017
Site: www.prweb.com

Busier, bigger SPIE Photonics West 2017 closed Thursday afternoon with approximately 23,000 total registered attendance, up yet again over the previous year. The largest growth was in technical attendance and in visitors to the more than 1,380 exhibiting companies in the Photonic West Exhibition, and 210-plus in the weekend BiOS Expo. SPIE Photonics West is sponsored by SPIE, the international society for optics and photonics, and ran 28 January through 2 February at Moscone Center in San Francisco. “The energy and excitement on the show floor were palpable, with many companies reporting a strong business environment and the need to hire additional skilled employees,” said Andrew Brown, SPIE Senior Director. “The record attendance ensured that exhibitors were kept busy showing their new products and discussing opportunities for sales.” Characteristic among the comments, Photonics West exhibitor Kevin Fogarty of Canon U.S.A., Inc., said that traffic was strong from the first hour. “Within one minute of the doors opening on the first day there were people at our booth; within 30 minutes, we had very good customers in deep conversation,” Fogarty said. BiOS Expo companies were also pleased. Among them was Scott Hamlin of MegaWatt Lasers Inc., who cited both strong volume and quality of leads. Hamlin said his company likes the traffic flow at BiOS because it allows more time to talk with visitors. “Everybody I talk to is doing real business, selling real products, getting real orders, and scheduling more,” said venture-capital and private-equity advisor John Dexheimer of LightWave, who led a panel discussion on managing business through global changes. “The success of Photonics West for attendees from industry, academia, and government labs is a powerful indicator of the vitality of the industry,” Brown said. “We heard repeatedly during the week just how important this event is for the community. At this event, they connect with valuable collaborators, present new research for the first time, introduce new products, learn about the latest photonics technologies, and meet vendors who can provide the right equipment for the lab, factory, or clinic.” Conference rooms hosted some 4,700 presentations organized into topics in biomedical optics, lasers, and optoelectronics, with applications tracks in translational biophotonics, 3D printing, and brain research, all featuring talks from the field’s leading scientists and engineers. Among the highlights, Rafael Yuste, professor of neuroscience at Columbia University and a pioneer in optical methods for brain research, spoke on novel technologies for understanding the brain, to enable better treatment for disorders such as Alzheimer’s disease, schizophrenia, autism, epilepsy, and traumatic brain injury. Harald Haas, University of Edinburgh and pureLiFi, Ltd., gave an update on the latest advances in LiFi installations now proliferating around the world, using light generated by LEDs to stream data to computers. Karsten Danzmann, Max Planck Institute for Gravitational Physics and Leibniz Universität Hannover, described developments leading up to the historic detection by LIGO (the Laser Interferometer Gravitational-Wave Observatory) in late 2015 of gravitational waves — and the exciting technology going forward. Advanced LIGO dramatically improved capabilities, he said, as has LISA Pathfinder, a satellite mission launched in December 2015 whose payload includes the first laser interferometer in space. The comprehensive technical and course programs plus numerous networking activities and industry programs ensure that Photonics West remains the must-attend event for building business and research partnerships, and accessing the most current market and technology information, Brown said. “From manufacturing to healthcare, consumer products to communications, all segments of our industry are seeing strong growth,” he said. “SPIE is delighted to be a key factor in fueling the ecosystem through the Photonics West conference and trade show.” SPIE Photonics West 2018 will run 27 January through 1 February at Moscone Center. SPIE is the international society for optics and photonics, an educational not-for-profit organization founded in 1955 to advance light-based science, engineering, and technology. The Society serves nearly 264,000 constituents from approximately 166 countries, offering conferences and their published proceedings, continuing education, books, journals, and the SPIE Digital Library. In 2016, SPIE provided more than $4 million in support of education and outreach programs. http://www.spie.org


News Article | February 15, 2017
Site: cerncourier.com

The LIGO experiment has started its second observation run, with further upgrades in store and several other gravitational-wave observatories planned. L’expérience aLIGO, qui a réalisé la première détection d’ondes gravitationnelles l’année passée, a entamé sa deuxième campagne d’observation. Des améliorations sont prévues pour le futur, et d’autres observatoires terrestres sont également en projet dans le monde. À cela s’ajoute le succès de la mission LISA, de bon augure pour un futur détecteur d’ondes gravitationnelles dans l’espace. La sensibilité extraordinairement élevée qu’il a fallu atteindre pour détecter les infimes déplacements causés par les ondes gravitationnelles (plus de 200 fois plus petits que le rayon d’un proton) a été l’aboutissement de dizaines d’années de recherche et de développement dans la réduction du bruit et l’amélioration de l’optique. Gravitational waves alternatively compress and stretch space–time as they propagate, exerting tidal forces on all objects in their path. Detectors such as Advanced LIGO (aLIGO) search for this subtle distortion of space–time by measuring the relative separation of mirrors at the ends of long perpendicular arms, which form a simple Michelson interferometer with Fabry–Perot cavities in the arms: a beam splitter directs laser light to mirrors at the ends of the arms and the reflected light is recombined to produce an interference pattern. When a gravitational wave passes through the detector, the strain it exerts changes the relative lengths of the arms and causes the interference pattern to change. The arms of the aLIGO detectors are each 4 km long to help maximise the measured length change. Even on this scale, however, the induced length changes are tiny: the first detected gravitational waves, from the merger of two black holes, changed the arm length of the aLIGO detectors by just 4 × 10–18 m, which is approximately 200 times smaller than the proton radius. Achieving the fantastically high sensitivity required to detect this event was the culmination of decades of research and development. The idea of using an interferometer to detect gravitational waves was first concretely proposed in the 1970s and full-scale detectors began to be constructed in the mid-1990s, including GEO600 in Germany, Virgo in Italy and the LIGO project in the US. LIGO consists of detectors at two sites separated by about 3000 km – Hanford (in Washington state) and Livingston in Louisiana – and undertook its first science runs in 2002–2008. Following a major upgrade, the observatory restarted in September 2015 as aLIGO with an initial sensitivity four times greater than its predecessor. Since the detectors measure strain in space–time, the effective increase in volume, or event rate, of aLIGO is a factor 43 higher. A major issue facing aLIGO designers is to isolate the detectors from various noise sources. At a frequency of around 10 Hz, the motion of the Earth’s surface or seismic noise is about 10 orders of magnitude larger than required, with the seismic noise falling off at higher frequencies. A powerful solution is to suspend the mirrors as pendulums: a pendulum acts as a low-pass filter, providing significant reductions in motion at frequencies above the pendulum frequency. In aLIGO, a chain of four suspended masses is used to provide a factor 107 reduction in seismic motion. In addition, the entire suspension is attached to an advanced seismic isolation system using a variety of active and passive techniques, which further isolate noise by a factor 1000. At 10 Hz, and in the absence of other noise sources, these systems could already increase the sensitivity of the detectors to roughly 10–19 m/√(Hz). At even lower frequencies (10 μHz), the daily tides stretch and shrink the Earth by the order of 0.4 mm over 4 km. Another source of low-frequency noise arises from moving mass interacting with the detector mirrors via the Newtonian inverse square law. The dominant source of this noise is from surface seismic waves, which can produce density fluctuations of the Earth’s surface close to the interferometer mirrors and result in a fluctuating gravitational force on them. While methods of monitoring and subtracting this noise are being investigated, the performance of Earth-based detectors is likely to always be limited at frequencies below 1 Hz by this noise source. Thermal noise associated with the thermal energy of the mirrors and their suspensions can also cause the mirrors to move, providing a significant noise source at low-to-mid-range frequencies. The magnitude of thermal noise is related to the mechanical loss of the materials: similar to a high-quality wine glass, a material with a low loss will ring for a long time with a pure note because most of the thermal motion is confined to frequencies close to the resonance. For this reason, aLIGO uses fibres fabricated from fused silica – a type of very pure glass with very low mechanical loss – for the final stage of the mirror suspension. Pioneered in the GEO600 detector near Hanover in Germany, the use of silica fibres in place of the steel wires used in the initial LIGO detectors significantly reduces thermal noise from suspension. Low-loss fused silica is also used for the 40 kg interferometer mirrors, which use multi-layered optical coatings to achieve the high reflectivity required. For aLIGO, a new optical coating was developed comprising a stack of alternating layers of silica and titania-doped “tantala”, reducing the coating thermal noise by about 20%. However, at the aLIGO design sensitivity (which is roughly 10 times higher than the initial aLIGO set-up) thermal noise will be the limiting noise source at frequencies of around 60 Hz – close to the frequency at which the detectors are most sensitive. aLIGO also has much reduced quantum noise compared with the original LIGO. This noise source has two components: radiation-pressure noise and shot noise. The former results from fluctuations in the number of photons hitting the detector mirrors, which is more significant at lower frequencies, and has been reduced by using mirrors four times heavier than the initial LIGO mirrors. Photon shot noise, resulting from statistical fluctuations in the number of photons at the output of the detector, limits sensitivity at higher frequencies. Since shot noise is inversely proportional to the square root of the power, it can be reduced by using higher laser power. In the first observing run of aLIGO, 100 kW of laser power was circulating in the detector arms, with the potential to increase it to up to 750 kW in future runs. Optical cavities are also used to store light in the arms and build up laser power. In addition to reductions in these fundamental noise sources, many other technological improvements were required to reduce more technical noise sources. Improvements over the initial LIGO detector included a thermal compensation system to reduce thermal lensing effects in the optics, reduced electronic noise in control circuits and finer polishing of the mirror substrates to reduce the amount of scattered light in the detectors. Having detected their first gravitational wave almost as soon as they switched on in September 2015, followed by a further event a few months later, the aLIGO detectors began their second observation run on 30 November. Dubbed “O2”, it is scheduled to last for six months. More observation runs are envisaged, with more upgrades in sensitivity taking place between them. The next major upgrade, expected in around 2018, will see the injection of “squeezed light” to further reduce quantum noise. However, to gain the maximum sensitivity improvement from squeezing, a reduction in coating thermal noise is also likely to be required. With these and other relatively short-term upgrades, it is expected that a factor-two improvement over the aLIGO design sensitivity could be achieved. This would allow events such as the first detection to be observed with a signal-to-noise ratio almost 10 times better than the initial result. Further improvements in sensitivity will almost certainly require more extensive upgrades or new facilities, possibly involving longer detectors or cryogenic cooling of the mirrors. aLIGO is expected to soon be joined in observing runs by Advanced Virgo, giving a network of three geographically separated detectors and thus improving our ability to locate the position of gravitational-wave sources on the sky. Discussions are also under way for an aLIGO site in India. In Japan, the KAGRA detector is under construction: this detector will use cryogenic cooling to reduce thermal noise and is located underground to reduce seismic and gravity gradient effects. When complete, KAGRA is expected to have similar sensitivity to aLIGO. Longer term, in Europe a detector known as the Einstein Telescope (ET) has been proposed to provide a factor 10 more sensitivity than aLIGO. ET would not only have arms measuring 10 km long but would take a new approach to noise reduction using two very different detectors: a high-power room-temperature interferometer optimised for sensitivity at high frequencies, where shot noise limits performance, and a low-power cryogenic interferometer optimised for sensitivity at low frequencies (where performance is limited by thermal noise). ET would require significant changes in detector technology and also be constructed underground to reduce the effect of seismic noise and gravity-gradient noise on low-frequency sensitivity. Obtaining significantly improved sensitivity at lower frequencies is difficult on Earth because they are swamped by local mass motion. Gaining sensitivity at very low frequencies, which is where we must look for signals from massive black-hole collisions and other sources that will provide exquisite science results, is only likely to be achieved in space. This concept has been on the table since the 1970s and has evolved into the Laser Interferometer Space Antenna (LISA) project, which is led by the European Space Agency (ESA) with contributions from 14 European countries and the US. A survey mission called LISA Pathfinder was launched on 3 December 2015 from French Guiana. It is currently located 1.5 million  km away at the first Earth–Sun Lagrange point, and will take data until the end of May 2017. The aim of LISA Pathfinder was to demonstrate technologies for a space-borne gravitational-wave detector based on the same measurement philosophy as that used by ground-based detectors. The mission has clearly demonstrated that we can place test masses (gold–platinum cubes with 46 mm sides separated by 38 cm) into free fall, such that the only varying force acting on them is gravity. It has also validated a host of complementary techniques, including: operating a drag-free spacecraft using cold gas thrusters; electrostatic control of free-floating test masses; short-arm interferometry and test-mass charge control. When combined, these novel features allow differential accelerometry at the 10–15 g level, which is the sensitivity needed for a space-borne gravitational-wave detector. Indeed, if Pathfinder test-mass technology were used to build a full-scale LISA detector, it would recover almost all of the science originally anticipated for LISA without any further improvements. The success of Pathfinder, coming hot on the heels of the detection of gravitational waves, is a major boost for the international gravitational-wave community. It comes at an exceptional time for the field, with ESA currently inviting proposals for the third of its Cosmic Vision “large missions” programme. Developments are now needed to move from LISA Pathfinder to LISA proper, but these are now well understood and technology development programmes are planned and under way. The timeline for this mission leads to a launch in the early 2030s and the success of Pathfinder means we can look forward with excitement to the fantastic science that will result.


News Article | January 25, 2016
Site: phys.org

LISA Pathfinder is testing the key elements that could be used for a future mission to detect gravitational waves – ripples in spacetime predicted by Albert Einstein in his General Theory of Relativity. To this end, it will release two test masses into near-perfect free fall and measure their motion with unprecedented accuracy. LISA Pathfinder was launched on 3 December 2015 and arrived today in its orbit around 'L1', the first libration point of the Sun-Earth system, a virtual point in space some 1.5 million km from Earth towards the Sun. LISA Pathfinder's arrival came after a final thruster burn using the spacecraft's hard-working propulsion module on 20 January. The small, 64-second firing was designed to slightly change its speed and just barely tip the craft onto its new orbit about L1. Since launch, the propulsion module raised the orbit around Earth six times, the last of which kicked it towards L1. "We had planned two burns to get us into final orbit at L1, but only one was needed," says Ian Harrison, Spacecraft Operations Manager at ESA's ESOC operations centre in Darmstadt, Germany. The propulsion module separated from the science section at 11:30 GMT (12:30 CET) today after the combination was set spinning for stability. "Heat and vibration from the regular, hot thrusters on the propulsion module would cause too much disturbance during the spacecraft's delicate technology demonstration mission," notes Ian. "Primary propulsion during the rest of the mission will be provided by cold-gas microthrusters to keep us at L1." These small thrusters were used in the hours after separation to kill the spin and stabilise the spacecraft. Today's operations were monitored by the mission control and science teams at ESOC in real time via the Agency's deep-space station at Malargüe, Argentina. During this evening, the craft will be slowly turned to point towards Earth and, around midnight, establish a full communications link via ESA's New Norcia ground station, Australia. Next week, LISA Pathfinder's trajectory will be fine-tuned with a series of three microthruster bursts, taking it onto its final orbit, a 500 000 × 800 000 km orbit around L1. L1 was chosen because it is a quiet place in space, far away from large bodies such as Earth and is ideal for communications. Preparing the spacecraft's systems and payload for work has already begun, with the full platform, the thrusters and the Disturbance Reduction System having already been checked. Last week, the laser that will measure the most precise free-fall ever obtained in space was switched on and tested. Next month, the two identical test cubes will be released in two steps. First, the launch lock fingers on the eight corners of each cube will be retracted on 3 February. Then, other mechanisms that secure the cubes will be released on 15 and 16 February. This will enable the craft to begin, on 1 March, demonstrating that we can measure the separation of target masses with the extremely high accuracy required to measure gravitational waves from space in the future. The relative motion of the two cubes will be measured by laser to within a staggering a billionth of a millimetre.

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