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  • richardmitnick 1:29 pm on February 17, 2014 Permalink | Reply
    Tags: , , , , Jodrell Bank Centre for Astrophysics   

    From Jodrell Bank: “Massive neutrinos solve a cosmological conundrum” 

    Jodrell Bank Lovell Telescope
    Lovell

    Jodrell Bank Centre for Astrophysics

    10 Feb 2014
    No Writer Credit

    Scientists have solved a major problem with the current standard model of cosmology identified by combining results from the Planck spacecraft and measurements of gravitational lensing in order to deduce the mass of ghostly sub-atomic particles called neutrinos.

    The team, from the Universities of Manchester and Nottingham, used observations of the Big Bang and the curvature of space-time to accurately measure the mass of these elementary particles for the first time.

    The recent Planck spacecraft observations of the Cosmic Microwave Background (CMB) – the fading glow of the Big Bang – highlighted a discrepancy between these cosmological results and the predictions from other types of observations. The CMB is the oldest light in the Universe, and its study has allowed scientists to accurately measure cosmological parameters, such as the amount of matter in the Universe and its age. But an inconsistency arises when large-scale structures of the Universe, such as the distribution of galaxies, are observed.
    Professor Richard Battye, from The University of Manchester School of Physics and Astronomy, said: “We observe fewer galaxy clusters than we would expect from the Planck results and there is a weaker signal from gravitational lensing of galaxies than the CMB would suggest.

    cmb
    Map of the cosmic microwave background made by the European Space Agency’s Planck spacecraft. The results of this work on neutrinos were based in part on these observations. Credit: ESA, Low Frequency Instrument and High Frequency Instrument Consortia (2013).

    “A possible way of resolving this discrepancy is for neutrinos to have mass. The effect of these massive neutrinos would be to suppress the growth of dense structures that lead to the formation of clusters of galaxies.”

    Neutrinos interact very weakly with matter and so are extremely hard to study. They were originally thought to be massless but particle physics experiments have shown that neutrinos do indeed have mass and that there are several types, known as flavours by particle physicists. The sum of the masses of these different types has previously been suggested to lie above 0.06 eV (much less than a billionth of the mass of a proton).

    In this paper (published in Physical Review Letters on 7th February 2014), Professor Battye and co-author Dr Adam Moss, from the University of Nottingham, have combined the data from Planck with gravitational lensing observations in which images of galaxies are warped by the curvature of space-time. They conclude that the current discrepancies can be resolved if massive neutrinos are included in the standard cosmological model. They estimate that the sum of masses of neutrinos is 0.320 +/- 0.081 eV (assuming active neutrinos with three flavours).

    Dr Moss said: “If this result is borne out by further analysis, it not only adds significantly to our understanding of the sub-atomic world studied by particle physicists, but it would also be an important extension to the standard model of cosmology which has been developed over the last decade.”

    The paper is published in Physical Review Letters on 7th February and has been selected as an Editor’s choice.

    Jodrell Bank’s role in Planck

    This paper makes use of CMB data from the European Space Agency’s Planck spacecraft and from the South Pole Telescope.

    spt
    The 10 metre South Pole Telescope

    The South Pole Telescope (SPT) is a 10 metre (394 in) diameter telescope located at the Amundsen-Scott South Pole Station, Antarctica. The telescope is designed for observations in the microwave, millimeter-wave, and submillimeter-wave regions of the electromagnetic spectrum, with the particular design goal of measuring the faint, diffuse emission from the Cosmic Microwave Background (CMB).[1] The first major survey with the SPT–designed to find distant, massive, clusters of galaxies through their interaction with the CMB, with the goal of constraining the Dark Energy equation of state–was completed in October, 2011. In early 2012, a new camera was installed on the SPT with even greater sensitivity and the capability to measure the polarization of incoming light. This camera is designed to measure the so-called “B-mode” or “curl” component of the polarized CMB, leading to constraints on the mass of the neutrino and the energy scale of inflation.[2]

    The SPT collaboration is made up of over a dozen (mostly North American) institutions, including the University of Chicago, the University of California-Berkeley, Case Western Reserve University, Harvard/Smithsonian Astrophysical Observatory, the University of Colorado-Boulder, McGill University, University of California at Davis, Ludwig Maximilian University of Munich, Argonne National Laboratory, and the National Institute for Standards and Technology. It is funded by the National Science Foundation.

    Jodrell Bank Centre for Astrophysics is directly involved with the two lowest frequencies of the Low Frequency Instrument on board Planck, the 30 and 44 GHz radiometers. These have four and six detectors respectively, operating at 20 Kelvin (-253.15 degrees Celsius). The resolution on the sky is 33 and 27 arc minutes, and the sensitivity 1.6 and 2.4 micro K (over 12 months). The cryogenic low noise amplifiers which are the heart of the radiometers were developed at Jodrell Bank, with help from the National Radio Astronomy Observatory in Virginia, USA.

    Dr B Maffei and Dr G Pisano are involved in the other focal instrument, the HFI. First at Cardiff University and then at The University of Manchester, they have played a major role in the design, development and calibration of the Focal Plane Unit, in particular the cold optics, in collaboration with the Institut d’Astrophysique Spatiale, France, Maynooth University, Ireland and JPL/Caltech, USA.

    The work to understand the Galactic emission seen by Planck is being co-led from Jodrell Bank by Emeritus Professor Rod Davies and Dr Clive Dickinson. A number of projects are led by Jodrell Bank scientists, including Professor Richard Davis and Dr Clive Dickinson. Each of the 14 projects focuses on one aspect of the Galaxy as seen by Planck, including the electrons that gyrate in the Galactic magnetic field, the ionized gas that pervades the interstellar medium and the dust grains that emit across the entire frequency range that Planck is sensitive to. Jodrell Bank is also leading the calibration and identifying systematics in the LFI data.

    See the full article here.

    Jodrell Bank Centre for Astrophysics comprises research activities in astronomy and astrophysics at The University of Manchester, the world leading facilities of the Jodrell Bank Observatory, the e-MERLIN/VLBI National Facility and the Project Development Office of the Square Kilometre Array.

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  • richardmitnick 5:58 pm on October 31, 2013 Permalink | Reply
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    From Jodrell Bank: “Former missile-tracking telescope helps reveal fate of baby pulsar” 

    Jodrell Bank Lovell Telescope
    Lovell

    Jodrell Bank Centre for Astrophysics

    31st October 2013

    For further information contact:
    Aeron Haworth
    Media Relations
    Faculty of Engineering and Physical Sciences
    The University of Manchester
    Tel: 0161 275 8387
    Mob: 07717 881563
    Email: aeron.haworth@manchester.ac.uk

    A radio telescope once used to track ballistic missiles has helped astronomers determine how the magnetic field structure and rotation of the young and rapidly rotating Crab pulsar evolves with time. The findings are published in the journal Science today (Friday).

    The Crab pulsar is a neutron star which formed in a massive cosmic explosion seen in both Europe and China in AD 1054 as a bright star in the daytime sky. Now rotating 30 times a second, this highly-compact star emits beams of radio waves that, like a lighthouse, produce flashes each time it rotates. The star itself is only about 25 km across but contains the mass of nearly 1 million Earths.

    cp

    Professor Andrew Lyne and his colleagues from The University of Manchester report on a steady change in these flashes during a 22-year experiment watching the star, telling us about its very strong magnetic field and helping us learn about the otherwise-inaccessible interior of the star.

    The flashes, or pulses, come in pairs. The new observations show that the spacing of these pairs of pulses is increasing by 0.6 degrees per century, an unexpectedly large rate of evolution. The scientists have shown that this means that the magnetic pole is moving towards the equator.

    The astronomers employed a 42-ft telescope that was formerly used to track the Blue Streak missile at the Woomera Rocket Test Range in Australia until 1981, when it was dismantled, transported and re-erected at the Jodrell Bank Observatory in Cheshire, England. This relatively modest telescope has been used to observe the Crab pulsar almost daily for 31 years, during which time the pulsar has rotated 30 billion times, and Jodrell Bank has kept count of every rotation. The most accurate observations, made since 1991, show the small gradual change in the pulse spacing.


    The 42ft Radio Telescope at twilight.

    Study lead Andrew Lyne, an Emeritus Professor at Manchester, said that the most surprising aspect is that this change is happening so rapidly, when the interior of the star is superconducting, and the magnetic field should be frozen in position.

    Co-author Professor Sir Francis Graham Smith said: “This pulsar is just 960 years old, so while 22 years gives only a small sample of its lifetime, it is a much larger fraction of a stellar lifetime than astronomers usually get to study.”

    Dr Christine Jordan, who helps keep the telescope and observations running at Jodrell Bank, said: “It is amazing to think that this relatively small missile-tracking telescope, installed in Australia in 1974 by Marconi and donated to the Jodrell Bank Observatory in 1981 where it was converted to observe pulsars, has proved to be such a boon to astronomers. This is a real sword to ploughshare concept in action.”

    Dr Patrick Weltevrede, also of The University of Manchester, believes that this result will have important implications for our understanding of the evolution of pulsars and how they emit. He said: “The Crab pulsar is iconic; it is seen across the entire electromagnetic spectrum and is an exemplar and so this result provides vital clues about how these cosmic lighthouses shine and explaining a longstanding mystery about the way pulsars slow down over time.”

    See the full article here.

    Jodrell Bank Centre for Astrophysics comprises research activities in astronomy and astrophysics at The University of Manchester, the world leading facilities of the Jodrell Bank Observatory, the e-MERLIN/VLBI National Facility and the Project Development Office of the Square Kilometre Array.

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  • richardmitnick 2:18 pm on July 5, 2013 Permalink | Reply
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    From Jodrell Bank: “Cosmic radio bursts point to cataclysmic origins” 

    Jodrell Bank Lovell Telescope
    Lovell

    Jodrell Bank Centre for Astrophysics

    4th July 2013

    “Mysterious bursts of radio waves originating from billions of light years away have left the scientists who detected them speculating about their origins.

    The international research team, writing in the journal Science, rule out terrestrial sources for the four fast radio bursts and say their brightness and distance suggest they come from cosmological distances when the Universe was just half its current age.

    The burst energetics indicate that they originate from an extreme astrophysical event involving relativistic objects such as neutron stars or black holes.

    Study lead Dan Thornton, a PhD student at England’s University of Manchester and Australia’s Commonwealth Scientific and Industrial Research Organisation, said the findings pointed to some extreme events involving large amounts of mass or energy as the source of the radio bursts.

    He said: ‘A single burst of radio emission of unknown origin was detected outside our Galaxy about six years ago but no one was certain what it was or even if it was real, so we have spent the last four years searching for more of these explosive, short-duration radio bursts. This paper describes four more bursts, removing any doubt that they are real. The radio bursts last for just a few milliseconds and the furthest one that we detected was several billion light years away.’

    Astonishingly, the findings – taken from a tiny fraction of the sky – also suggest that there should be one of these signals going off every 10 seconds. Max-Planck Institute Director and Manchester’s Professor Michael Kramer explained: ‘The bursts last only a tenth of the blink of an eye. With current telescopes we need to be lucky to look at the right spot at the right time. But if we could view the sky with ‘radio eyes’ there would be flashes going off all over the sky every day.’

    The team, which included researchers from the UK, Germany, Italy, Australia and the US, used the CSIRO Parkes 64metre radio telescope in Australia to obtain their results.

    ciro
    CSIRO Parkes Radio Telescope

    Co-author Professor Matthew Bailes, from the Swinburne University of Technology in Melbourne, thinks the origin of these explosive bursts may be from magnetic neutron stars, known as ‘magnetars’. He said: ‘Magnetars can give off more energy in a millisecond than our Sun does in 300,000 years and are a leading candidate for the burst.’

    The researchers say their results will also provide a way of finding out the properties of space between the Earth and where the bursts occurred.

    Author Dr Ben Stappers, from Manchester’s School of Physics and Astronomy, said: ‘We are still not sure about what makes up the space between galaxies, so we will be able to use these radio bursts like probes in order to understand more about some of the missing matter in the Universe. We are now starting to use Parkes and other telescopes, like the Lovell Telescope of the University of Manchester, to look for these bursts in real time.”

    See the full article here.

    Jodrell Bank Centre for Astrophysics comprises research activities in astronomy and astrophysics at The University of Manchester, the world leading facilities of the Jodrell Bank Observatory, the e-MERLIN/VLBI National Facility and the Project Development Office of the Square Kilometre Array.

    Jodrell Bank e-Merlin

    ScienceSprings is powered by MAINGEAR computers

    SKA Square Kilometer Array

     
  • richardmitnick 3:39 pm on March 2, 2013 Permalink | Reply
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    From Jodrell Bank: “Image of the Month – The Trifid Nebula, M20″ 

    Jodrell Bank Lovell Telescope
    Lovell

    Jodrell Bank Centre for Astrophysics

    All of the below images are of the Trifid Nebula

    trifid

    “The Trifid Nebula is a star formation region in the constellation of Sagittarius, the Archer, that lies at a distance of about 9,000 light years and spans a distance of about 10 light years. The three prominent dust lanes that come together in the centre give it its name. It is the ultra-violet light from a single massive star at its heart that excites the surrounding gas to glow whilst its visible light shows the wonderful detail in the dust lanes. This beautiful image is the work of Martin Pugh, who provided the colour data, and Robert Gendler who assemble the image using additional imaging data from the HST and Subaru Telescopes. Wonderful!”

    See the original article here.

    Credits Subaru Telescope (NAOJ), Hubble Space telescope, ESA,NASA, Martin Pugh; processing by Robert Gendler.

    trifid2
    Another view, Hubble

    spitzer
    Spitzer’s infrared view

    eso
    ESO’s view

    Jodrell Bank Centre for Astrophysics comprises research activities in astronomy and astrophysics at The University of Manchester, the world leading facilities of the Jodrell Bank Observatory, the e-MERLIN/VLBI National Facility and the Project Development Office of the Square Kilometre Array.

    Jodrell Bank e-Merlin

    ScienceSprings is powered by MAINGEAR computers

    SKA Square Kilometer Array

     
  • richardmitnick 4:13 pm on January 25, 2013 Permalink | Reply
    Tags: , , , , e-Merlin, Jodrell Bank Centre for Astrophysics,   

    From Jodrell Bank: “e-MERLIN’s deep radio survey of the Hubble Deep Field: first results” 

    Jodrell Bank Lovell Telescope
    Lovell

    Jodrell Bank Centre for Astrophysics

    27 March 2012 [in RSS Jan 25, 2013]

    “A team of astronomers at Jodrell Bank Observatory have begun the deepest ever high-resolution radio imaging of the region around the Hubble Deep Field (HDF), the images originally captured by the Hubble Space Telescope (HST) in the mid 1990s. The HDF led to the discovery of numerous galaxies billions of light years distant and provided direct visual evidence of the evolution of the Universe. First results from the new imaging, which uses observations from the UK’s newly upgraded e-MERLIN radio telescope array together with the EVLA radio array based in New Mexico, show galaxies some 7 billion light years away in unprecedented detail.

    hdf
    About 1,500 galaxies are visible in this deep view of the universe, taken by allowing the Hubble Space Telescope to stare at the same tiny patch of sky for 10 consecutive days in 1995. The image covers an area of sky only about width of a dime viewed from 75 feet away. Credit: Robert Williams and the Hubble Deep Field Team (STScI) and NASA

    e-MERLIN is an array of radio telescopes distributed across the United Kingdom connected together by optical fibres. Data from each telescope is sent across this network to Jodrell Bank where a device known as a ‘correlator’ processes them into a single image. This technique, known as interferometry, simulates a single radio telescope hundreds of kilometres across and produces exceptionally sharp images of astronomical objects.

    EVLA is a similar more compact array in New Mexico in the United States that shows the coarser structure of objects and complements the e-MERLIN observations. The two arrays started to survey the HDF region in 2011 and the team expect the project to be completed in the next few years.

    hdf2
    Image composed from e-MERLIN and EVLA observations in C-band. The width of the whole field is approximately 1/4 of a degree (the same diameter as half a full moon). The inset images illustrate the effectiveness of e-MERLIN’s capabilities in revealing the structure of galaxies even at distances of billions of the light years. Bottom left: An interesting example of an AGN galaxy with large lobes thought to be caused by jets, emanating from a central black hole, interacting with interstellar material. Bottom right: An FR1 type AGN galaxy. Top left: A more typical AGN type galaxy. Top right: An AGN with star formation characteristic emission detected at an estimated distance of 7.5 billion light-years. Credit: N. Wrigley / Jodrell Bank Centre for Astrophysics

    The first wide-band images of the whole HDF region capture the brightest objects in the field at sub-arcsecond resolution, equivalent to being able to distinguish a ten pence piece at a distance of over 5 kilometres. The pictures were assembled by Mr [Nick] Wrigley under the supervision of Dr Rob Beswick and Dr Tom Muxlow at the Jodrell bank Centre for Astrophysics in Manchester. The image in the background, observed using the EVLA, shows the unresolved emission from whole galaxies, whereas the inset images produced using mapping in combination with e-MERLIN show the fine detail.

    This new work is just the start of a multi-year survey of the HDF and provides a glimpse of the capabilities of wide-band (broadband data transmission) synthesis imaging now possible with simultaneous use of the e-MERLIN and EVLA arrays. Crucially, the e-MERLIN and EVLA correlators now generate compatible data allowing future observations to be combined like never before.”

    See the full article here.

    Jodrell Bank Centre for Astrophysics comprises research activities in astronomy and astrophysics at The University of Manchester, the world leading facilities of the Jodrell Bank Observatory, the e-MERLIN/VLBI National Facility and the Project Development Office of the Square Kilometre Array.

    Jodrell Bank e-Merlin

    ScienceSprings is powered by MAINGEAR computers

    SKA Square Kilometer Array

     
  • richardmitnick 3:40 pm on January 25, 2013 Permalink | Reply
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    From Jodrell Bank: “Astronomers discover sandstorms in space” 

    Jodrell Bank Lovell Telescope
    Lovell

    Jodrell Bank Centre for Astrophysics

    11 April 2012

    Astronomers at The University of Manchester believe they have found the answer to the mystery of a powerful superwind which causes the death of stars.

    m82
    M82: Starburst Galaxy with a Superwind

    Writing in Nature, the team of researchers used new techniques which allowed them to look into the atmospheres of distant, dying stars.

    The team, lead by Barnaby Norris from the University of Sydney in Australia, includes scientists from the Universities of Manchester, Paris-Diderot, Oxford and Macquarie University, New South Wales. They used the Very Large Telescope in Chile, operated by the European Southern Observatory.

    ESO VLT At Night
    VLT at Cerro Paranal in the Atacama Desert, Chile

    Stars like the Sun end their lives with a ‘superwind’, 100 million times stronger than the solar wind. This wind occurs over a period of 10,000 years, and removes as much as half the mass of the star. At the end, only a dying and fading remnant of the star will be left. The Sun will begin to throw out these gases in around five billion years. The cause of this superwind has remained a mystery. Scientists have assumed that they are driven by minute dust grains, which form in the atmosphere of the star and absorb its light. The star light pushes the dust grains (silicates) away from the star. However, models have shown that this mechanism does not work well. The dust grains become too hot, and evaporate before they can be pushed out.

    The scientists have now discovered that the grains grow to much larger sizes than had previously been thought. The team found sizes of almost a micrometre – as small as dust, but huge for stellar winds. Grains of this size behave like mirrors, and reflect starlight, rather than absorbing it. This leaves the grains cool, and the star light can push them out without destroying them. This may be the solution to the mystery of the superwind. The large grains are driven out by the star light at speeds of 10 kilometres per second, or 20 thousand miles per hour – the speed of a rocket. The effect is similar to a sandstorm. Compared to grains of sands, the silicates in the stellar winds are still tiny.”

    See the full article here.

    Jodrell Bank Centre for Astrophysics comprises research activities in astronomy and astrophysics at The University of Manchester, the world leading facilities of the Jodrell Bank Observatory, the e-MERLIN/VLBI National Facility and the Project Development Office of the Square Kilometre Array.

    Jodrell Bank e-Merlin

    SKA Square Kilometer Array

     
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