Tagged: University of Bern Toggle Comment Threads | Keyboard Shortcuts

  • richardmitnick 11:07 am on August 31, 2019 Permalink | Reply
    Tags: "exo-Io", A rocky extrasolar moon (exomoon) with bubbling lava may orbit a planet 550 light-years away from us., , , , , The exoplanet system WASP-49b, University of Bern   

    From The University of Bern: “Hints of a volcanically active exomoon” 

    From The University of Bern

    2019/08/29
    Dr. Apurva Vikram Oza
    +41 31 631 47 36
    apurva.oza@space.unibe.ch

    1
    Artist’s composition of a volcanic exo-Io undergoing extreme mass loss. The hidden exomoon is enshrouded in an irradiated gas cloud shining in bright orange-yellow, as would be seen with a sodium filter. Patches of sodium clouds are seen to trail the lunar orbit, possibly driven by the gas giant’s magnetosphere.

    A rocky extrasolar moon (exomoon) with bubbling lava may orbit a planet 550 light-years away from us. This is suggested by an international team of researchers led by the University of Bern on the basis of theoretical predictions matching observations. The “exo-Io” would appear to be an extreme version of Jupiter’s moon Io.

    Jupiter’s moon Io is the most volcanically active body in our solar system. Today, there are indications that an active moon outside our solar system, an exo-Io, could be hidden at the exoplanet system WASP-49b. “It would be a dangerous volcanic world with a molten surface of lava, a lunar version of close-in Super Earths like 55 Cancri-e” says Apurva Oza, postdoctoral fellow at the Physics Insitute of the University of Bern and associate of the NCCR PlanetS, “a place where Jedis go to die, perilously familiar to Anakin Skywalker.” But the object that Oza and his colleagues describe in their work seems to be even more exotic than Star Wars science fiction: the possible exomoon would orbit a hot giant planet, which in turn would race once around its host star in less than three days – a scenario 550 light years away in the inconspicuous constellation of Lepus, underneath the bright Orion constellation.

    Sodium gas as circumstantial evidence

    Astronomers have not yet discovered a rocky moon beyond our solar system and it’s on the basis of circumstantial evidence that the researchers in Bern conclude that the exo-Io exists: Sodium gas was detected at the WASP 49-b at an anomalously high-altitude. “The neutral sodium gas is so far away from the planet that it is unlikely to be emitted solely by a planetary wind,” says Oza. Observations of Jupiter and Io in our solar system, by the international team, along with mass loss calculations show that an exo-Io could be a very plausible source of sodium at WASP 49-b. “The sodium is right where it should be” says the astrophysicist.

    Tides keep the system stable

    Already in 2006, Bob Johnson of the University of Virginia and the late Patrick Huggins at New York University, USA had shown that large amounts of sodium at an exoplanet could point to a hidden moon or ring of material, and ten years ago, researchers at Virginia calculated that such a compact system of three bodies: star, close-in giant planet and moon, can be stable over billions of years. Apurva Oza was then a student at Virginia, and after his PhD on moons’ atmospheres in Paris, decided to pick up the theoretical calculations of these researchers. He now publishes the results of his work together with Johnson and colleagues in The Astrophysical Journal.

    “The enormous tidal forces in such a system are the key to everything,” explains the astrophysicist. The energy released by the tides to the planet and its moon keeps the moon’s orbit stable, simultaneously heating it up and making it volcanically active. In their work, the researchers were able to show that a small rocky moon can eject more sodium and potassium into space through this extreme volcanism than a large gas planet, especially at high altitudes. “Sodium and potassium lines are quantum treasures to us astronomers because they are extremely bright,” says Oza, “the vintage street lamps that light up our streets with yellow haze, is akin to the gas we are now detecting in the spectra of a dozen exoplanets.”

    “We need to find more clues”

    The researchers compared their calculations with these observations and found five candidate systems where a hidden exomoon can survive against destructive thermal evaporation. For WASP 49-b the observed data can be best explained by the existence of an exo-Io. However, there are other options. For example, the exoplanet could be surrounded by a ring of ionized gas, or non-thermal processes. “We need to find more clues,” Oza admits. The researchers are therefore relying on further observations with ground-based and space-based instruments.

    “While the current wave of research is going towards habitability and biosignatures, our signature is a signature of destruction“, says the astrophysicist. A few of these worlds could be destroyed in a few billion years due to the extreme mass loss. “The exciting part is that we can monitor these destructive processes in real time, like fireworks”, says Oza.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The University of Bern (German: Universität Bern, French: Université de Berne, Latin: Universitas Bernensis) is a university in the Swiss capital of Bern and was founded in 1834.[2] It is regulated and financed by the Canton of Bern. It is a comprehensive university offering a broad choice of courses and programs in eight faculties and some 150 institutes. With around 17,512 students, the University of Bern is the third biggest University in Switzerland.

    The University of Bern operates at three levels: university, faculties and institutes. Other organizational units include interfaculty and general university units. The university’s highest governing body is the Senate, which is responsible for issuing statutes, rules and regulations. Directly answerable to the Senate is the University Board of Directors, the governing body for university management and coordination. The Board comprises the Rector, the Vice-Rectors and the Administrative Director. The structures and functions of the University Board of Directors and the other organizational units are regulated by the Universities Act. The University of Bern offers about 39 bachelor and 72 master programs, with enrolments of 7,747 and 4,523, respectively. The university also has 2,776 doctoral students. Around 1,561 bachelor, 1,489 master’s degree students and 570 PhD students graduate each year. For some time now, the university has had more female than male students; at the end of 2016, women accounted for 56% of students.

     
  • richardmitnick 3:22 pm on December 7, 2017 Permalink | Reply
    Tags: , , , , , , This telescope is supposed to measure the diameter of exoplanets which are light-years away from us and pass in front of their host star, , University of Bern   

    From University of Bern: ‘The history of CHEOPS” 

    The University of Bern

    Engineers at the University of Bern are developing the CHEOPS space telescope. From Earth´s orbit, this telescope is supposed to measure the diameter of exoplanets which are light-years away from us and pass in front of their host star. Swiss astronomers had the idea for CHEOPS back in 2008.

    ESA/CHEOPS

    Willy Benz, professor at the Physics Institute at the University of Bern, actually wanted to travel during a semester-long sabbatical in 2008. Instead of spending this sabbatical at foreign universities, the astrophysicist sat at his desk at home and worked on a research proposal. The Swiss National Science Foundation had announced that they would be appointing new National Centres of Competence in Research (NCCR) and Willy Benz wanted to submit a proposal for planetary research together with his colleague in Geneva, Didier Queloz.

    In 1995 the former doctoral student Queloz and his supervising professor Michel Mayor discovered the first exoplanet orbiting a sun-like star. Benz also received his doctorate from Mayor at the University of Geneva nine years earlier. Already in 2000, Benz submitted a proposal for a National Centre of Competence in Research on exoplanetary research to the National Science Foundation, but his proposal was rejected. “That’s science fiction, they told me in an interview back then,” recalls the astrophysicist. In the year 2000, dozens of exoplanets had already been identified, in 2008 there were 300, today there are more than 3,000.

    1
    Testing CHEOPS in the thermal vacuum chamber at the University of Bern. (Photo UniBern)

    The first of these distant planets orbiting sun-like stars were discovered by astronomers who were able to demonstrate that the host stars move periodically towards and away from us because both star and planet rotate around their common centre of mass under the influence of gravity. This technique is called the radial velocity method. It works well with bright stars (at least 11 mag) and provides measurements to calculate the mass of the planet. Soon astronomers also used a second method: If a planet passes directly in front of its star, it causes a kind of mini-eclipse; the brightness of the star periodically decreases by a tiny fraction. Thanks to these so-called transits, the diameter of the planet can be determined. The French satellite COROT, which was launched in 2006, and later NASA’s Kepler mission, used the transit method with great success.

    Raial Veocity Method. Las Cumbres Observatory

    Planet transit. NASA/Ames

    ESA/CoRoT

    NASA/Kepler Telescope

    Progress thanks to new instruments

    “In the field of astrophysics today, progress is mostly made thanks to new instruments,” explains Benz. “When we worked on our second NCCR proposal in 2008, we wanted to propose not only scientific research projects but also the construction of hardware, including a Swiss exoplanetary satellite.” This satellite was supposed to be unique because of a new observation strategy. “Transit measurement is a great method,” explains the expert, “but, unfortunately, it has almost only identified planets whose stars are not very bright.” Their average magnitude is only 14 to 15. The explanation for this is that only a very small percentage of the stars are orbited by planets whose orbits lie exactly in our line of sight. If you really want to discover transits, you have to target a large number of stars. COROT and Kepler targeted about 100,000, but this was only possible because the satellites were limited to a narrow region. The bright stars, however, are spread all over the sky.

    “At the time, we thought it would be possible to build a small satellite that would not focus on a narrow area, but would observe bright stars everywhere in the sky, stars that are already known to possess a planet because of the radial velocity method,” Benz explains. The combination of the two detection methods is particularly interesting. If the mass is known on the basis of the radial velocity and the diameter of a planet is known due to the transit, its density can be calculated. “We then know whether the planet is mainly composed of rock or gas,” says Benz – a particularly important result in the context of the search for Earth-like planets.

    2
    Professor Willy Benz with a 1:2 scale model of CHEOPS. (Photo Alessandro Della Bella)

    In 2009, Benz and Queloz submitted their applications for a National Centre of Competence in Research, including a feasibility study for a space telescope. When searching for the name of the satellite, the astrophysicists knew that “CH” for Switzerland would come at the beginning and that the abbreviation should be catchy. This is how they came up with “CH ExOPlanet Satellite” or CHEOPS for short. The application for planetary research was one of 13 projects that the National Science Foundation rated as excellent with a grade of A. “Unfortunately, the project was not chosen in the end,” Benz says, “I was very disappointed, having sacrificed my entire sabbatical.”

    Persistence pays off

    The astrophysicist did not give up and was later able to negotiate with the rector of the University of Berne and the State Secretary for Education and Research on how the dream of a Swiss satellite could still be pursued. As a result of his persistence, the federal government and RUAG financed the feasibility report as industrial representatives, and the University of Bern founded the “Center for Space and Habitability” (CSH). “In the feasibility report, we quickly realized that the satellite project alone would be too expensive for Switzerland,” Benz says. Sweden and Austria, where RUAG operated its branches, were the first European partners, and others soon followed.

    While the Swiss were still working on the CHEOPS feasibility study, the European Space Agency (ESA) was discussing the possibility of a new satellite programme. In addition to the existing large and medium-sized (L- and M-class) missions, the smaller ESA member states in particular wanted to launch an S-class mission. The development time for these missions should not exceed four years and the cost should not exceed a prescribed limit set by ESA. The ESA Member States agreed on an experiment and issued a first S-mission call in March 2012.

    As chairman of the scientific committee advising ESA, Benz was well informed about the discussions and decisions of the ESA delegates – and was prepared to participate in the call for proposals with the CHEOPS study. While most of the others had only three months to work out their proposals, the Swiss could rely on the extensive preparatory work done in the feasibility study and benefit from Benz’s ‘insider’ knowledge. “I knew the objections and doubts that some ESA delegates had previously put forward, and I made sure that we went in the right direction in our proposal and, for example, prevented cost explosions.” Although they originally wanted to use CHEOPS to observe the transits in two different wavelengths, they decided against an infrared instrument for cost reasons.

    No holiday plans

    3
    The CHEOPS team at the University of Bern assembles the flight model in the clean room. (Photo PlanetS)

    In June 2012, Benz submitted the proposal for the CHEOPS mission, now called ‘CHaracterizing ExOPlanets Satellite’. It was one of 26 proposed projects submitted. When the ESA Scientific Panel met in Madrid in October 2012 to select the winner, Chairman Benz stayed away from the conference because of his conflict of interest and waited in his Bern office for a call from the committee’s secretary. “I remember his first sentence very well,” Benz says. “He said, ‘you shouldn’t make any plans for holidays in the next four years’.”

    CHEOPS started as a joint project between Switzerland and ESA. The University of Bern is responsible for the construction of the space telescope and heads the consortium of 11 ESA member states participating in the mission. The satellite platform will be built in Spain. The mission’s operations centre is also located there, while the research centre is being set up at the University of Geneva. The launch is scheduled for the end of 2018 with a Soyuz rocket from Kourou. ESA will bear half of the total costs of around 100 million Euros. Switzerland will contribute around 30 million Euros, while the other partners involved will contribute the remainder of the finances needed for this undertaking.

    “Although we were not selected by the National Science Foundation in 2009, everything worked out very nicely in the end,” concludes Benz. “Despite the additional stress and a lot of work, we were able to start our projects and are now close to the launch!” In addition, The National Research Centre was also awarded to the planetary scientists on their third attempt. In June 2014, Willy Benz and co-director Stéphane Udry, professor at the University of Geneva, launched the NCCR PlanetS, in which the ETH Zurich and ETH Lausanne, as well as the University of Zurich are also involved. “This shows that you should never give up,” says Willy Benz. (bva)

    For more information please visit http://cheops.unibe.ch

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    The University of Bern (German: Universität Bern, French: Université de Berne, Latin: Universitas Bernensis) is a university in the Swiss capital of Bern and was founded in 1834.[2] It is regulated and financed by the Canton of Bern. It is a comprehensive university offering a broad choice of courses and programs in eight faculties and some 150 institutes. With around 17,512 students, the University of Bern is the third biggest University in Switzerland.

    The University of Bern operates at three levels: university, faculties and institutes. Other organizational units include interfaculty and general university units. The university’s highest governing body is the Senate, which is responsible for issuing statutes, rules and regulations. Directly answerable to the Senate is the University Board of Directors, the governing body for university management and coordination. The Board comprises the Rector, the Vice-Rectors and the Administrative Director. The structures and functions of the University Board of Directors and the other organizational units are regulated by the Universities Act. The University of Bern offers about 39 bachelor and 72 master programs, with enrolments of 7,747 and 4,523, respectively. The university also has 2,776 doctoral students. Around 1,561 bachelor, 1,489 master’s degree students and 570 PhD students graduate each year. For some time now, the university has had more female than male students; at the end of 2016, women accounted for 56% of students.

     
  • richardmitnick 1:11 pm on July 5, 2017 Permalink | Reply
    Tags: , Cosmic ray tagger, FNAL/SBND, , , , University of Bern   

    From FNAL: “SBND’s cosmic ray tagger begins taking data” 

    FNAL II photo

    FNAL Art Image
    FNAL Art Image by Angela Gonzales

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    June 28, 2017
    Igor Kreslo

    1
    Members of the Short-Baseline Near Detector collaboration install the cosmic ray tagger in the SBND building. The cosmic ray tagger is made of the shiny, rectangular panels on the building floor. Photo: Reidar Hahn.

    On the morning of June 22, an important component of the Short-Baseline Near Detector (SBND) began taking data.

    The component, called the cosmic ray tagger, is the first of SBND’s subdetectors to be completed and operational.

    The SBND collaboration is constructing the Short-Baseline Near Detector piece by piece, and with the completion of the cosmic ray tagger, we’ve reached a construction and operations milestone.

    The SBND’s sought-after particle is the neutrino — a fleeting, difficult-to-capture particle. Adding to the difficulty is the fact that cosmic rays from outer space cloud the sought-after neutrino signal in the detector. The cosmic ray tagger, or CRT, is designed to identify the cosmic rays that rain down on the detector so scientists can subtract those traces from their data, revealing the neutrino signal.

    By functionality it is similar to the one installed earlier at the MicroBooNE detector, which you may have read about.

    The SBND collaboration installed and commissioned the cosmic ray tagger this month — in only two weeks. The CRT is composed of many finely grained modules capable of measuring an interaction instance to the nanosecond and to within a centimeter of its location in the CRT.

    With the newly operational cosmic ray tagger in its current configuration, SBND is currently characterizing the flux of particles called muons. These muons are produced by neutrinos from the Booster Neutrino Beamline so that scientists can measure their parameters in the SBND pit, where SBND will be built. Data taken during this characterization stage will be a great asset on the way to simulation and analysis for the whole SBND detector later on.

    The collaboration will continue to take data using the beam from the Booster Neutrino Beamline, as well as from cosmic rays, until the accelerator shutdown in July. When the accelerator complex restarts in October, we will restart data-taking using the CRT.

    We are grateful to collaborators at the University of Bern who designed and produced the CRT modules. And the swift installation and commissioning was possible thanks only to the tremendous dedication and commitment of many colleagues from the SBND collaboration as well as great support from Fermilab technical personnel.

    See the full article here .

    Please help promote STEM in your local schools.

    STEM Icon

    Stem Education Coalition

    FNAL Icon
    Fermilab Campus

    Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics. Fermilab is America’s premier laboratory for particle physics and accelerator research, funded by the U.S. Department of Energy. Thousands of scientists from universities and laboratories around the world
    collaborate at Fermilab on experiments at the frontiers of discovery.

     
c
Compose new post
j
Next post/Next comment
k
Previous post/Previous comment
r
Reply
e
Edit
o
Show/Hide comments
t
Go to top
l
Go to login
h
Show/Hide help
shift + esc
Cancel
%d bloggers like this: