Current Events
Advanced Particle Phenomenology
in the
LHC era
A European computational astrophysics programme
Conferences & Workshops:
Past Events
Conferences:
- Moriond Jamboree, 04/2011, Uni Irchel
- Dark Matter in the Sky and Underground, 09/2010, Zürich
- RADCOR 2009: 10/2009, Ascona
- CosmoStats09: 07/2009, Ascona
- Frontiers in Computational Astrophysics: 07/2008, Ascona
- From Protostellar Cores to Disk Galaxies, 09/2007, Zürich
- Formation of Disk Galaxies, 06/2005, Ascona.
Graduate Schools:
- LHCPhenoNet Winter School 2012, 22-29 January 2012, Ascona, Switzerland
- CHIPP PhD Winter School 2010
- CHIPP PhD Winter School 2008
- Saas Fee 2007, "The Origin of the Galaxy and Local Group"
Workshops:
- Zurich Phenomenology Workshop 2012: Higgs search confronts theory, ETH, 9.1.-12.1.12
- The Wengen 2 Workshop, 10/2010, Wengen
- LISA Massive Black Hole Binaries, 2010, Zürich
- The New, the Rare and the Beautiful workshop, 2010, Zürich
- Workshop on Higgs Boson Phenomenology, 2009, Zürich
- QCD and Strings, 2008, Zürich
- Workshop on Gauge Theory and String Theory, 2008, Zürich
- KET LHC-D Workshop, 2008, Zürich
- Workshop HP², 2006, Zürich
- Comp. Astrophysics, 2004, Wengen
News
Dec 2011
Erstmals massearmer Stern in Kugelsternhaufen nachgewiesen
Selbst stärkste Hightech-Teleskope können weit entfernte massearme und somit lichtschwache Sterne kaum erfassen. Jetzt weist ein Astrophysiker der Universität Zürich zusammen mit Forschern aus Polen und Chile erstmals mittels Mikrolinseneffekt einen massearmen Stern im Kugelsternhaufen M22 nach. Das Resultat deutet darauf hin, dass die Gesamtmasse von Kugelsternhaufen möglicherweise ohne die rätselhafte Dunkle Materie zu erklären ist.
Milchstrasse mit Kugelsternhaufen M22
Read the full article on the University of Zurich website:
Nov 2011
Asteroid in Sicht
In der Nacht von Dienstag auf Mittwoch wird Asteroid «2005 YU55» an der Erde in einem Abstand von 325'000 Kilometer vorbeisausen. Auswirkungen werden auf der Erde nicht zu spüren sein. Irgendwann in der Zukunft wird es für die Erde aber wieder gefährlich werden, erklärt Ben Moore, Professor für Astrophysik an der Universität Zürich.
Read the full article on the University of Zurich website:
http://www.uzh.ch/news/articles/2011/asteroid-in-sicht.html
Sep 2011
Earth-Moon planetary systems: TV coverage
May 2011
How common are Earth-Moon planetary systems?
Our Moon formed via a giant impact between our young Earth and a Mars sized proto-planet over four billion years ago. The material torn from the Earth’s surface during the collision accumulated in orbit and formed our familiar satellite. After its formation the Moon was ten times closer to the Earth than it is today and it has drifted slowly away to its present position. Its early intense gravitationally attraction would have caused tidal waves to pass across the Earth’s surface several times per day which may have influenced the initial development of life.
Read More »»
Read the article in The "SonntagsZeitung" 26.06.2011
The full article will be published in the journal Icarus and can be found here: http://xxx.soton.ac.uk/abs/1105.4616
Sep 2011 UPDATE: TV coverage
August 2010
26.08.2010
New model: supermassive black holes arrived early, find UniZH team in a paper on the 26 August issue of "Nature"
Direct formation of supermassive black holes via multi-scale gas inflows in galaxy mergers
Density map of the gas in the nuclear disk at three different times (columns a b and c). Upper panels: large-scale structure of the disk. Lower panels: zoom-in on the collapsing central cloud.
Previously published models of supermassive black hole formation have struggled to explain the fact that according to observations of distant quasars supermassive black holes were already in place less than a billion years after the Big Bang. A new series of numerical simulations from a team led by Lucio Mayer at the University of Zurich with PhD student Simone Callegari also from UniZH,
finds that the conditions for direct collapse into a supermassive black hole can arise naturally on this time scale from mergers between massive protogalaxies.Multi-scale gas inflows give rise to an unstable, massive nuclear gas disk that expands to form a sub-parsec scale gas cloud in only 100,000 years. The cloud undergoes gravitational collapse, which leads to the formation of a massive black hole.
The paper: http://www.nature.com/nature/journal/v466/n7310/full/nature09294.html
BBC:
http://www.bbc.co.uk/news/science-environment-11087715
SWISSINFO
http://www.swissinfo.ch/eng/science_technology/Scientists_target_super-massive_black_holes_.html?cid=26700656
UNIZH press release
http://www.mediadesk.uzh.ch/articles/2010/wie-supermassive-schwarze-loecher-entstanden.html
ORF
http://science.orf.at/stories/1658793/
USA TODAY
http://content.usatoday.com/topics/topic/Places,+Geography/Towns,+Cities,+Counties/Zurich
YAHOO:
http://news.yahoo.com/s/afp/20100825/sc_afp/spaceastronomyuniverseblackhole_20100825192515
WIRED
http://www.wired.com/wiredscience/2010/08/massive-black-hole-origin/#ixzz0xk2n1q00
January 2010
14.01.2010
Bulgeless galaxies with dark matter cores simulated
The picture shows the evolution of the assembly of the dwarf galaxy from high to low redshift.
Until now the origin of bulgeless galaxies and slowly rising rotation curves in low mass galaxies was a major puzzle of the cold dark matter model (CDM) for structure formation. Lucio Mayer and colleagues have performed the first supercomputer simulations that forms a bulgeless galaxy with a realistic rotation curve owing to unprecedented resolution.
The work is described on the journal Nature, issue of January 14, 2010.
"Bulgeless galaxies with dark matter cores simulated" Nature, 463, 203-206, 2010.
The simulation resolves the sites of star formation, giant molecular clouds, and shows that outflows generated by supernovae explosions prevent the formation of a bulge by removing baryonic mass from the center of the dwarf galaxy. Removal is fast enough to generate a rapid expansion of inner dark matter component. The final dark matter profile is thus shallower than that predicted by dark-matter only simulations.
Press release Uni Zurich:
http://www.mediadesk.uzh.ch/articles/2010/astrophysiker-loesen-raetsel-um-kalte-dunkle-materie-katastrophe-_en.html
Movies:
http://dl.dropbox.com/u/1180829/h799a2.mpg
http://dl.dropbox.com/u/1180829/h516.768gM.mpg
June 2009
25.06.09
Baby Milky Way modeled
Researchers unveil state-of-the-art simulation of galaxy formation
Galaxy Formation in Progress from Science News on Vimeo.
This movie models how a galaxy acquires most of its gas — the raw material for making stars. Red is hot gas, blue shows the cold streams of gas that flow like a river toward the galaxy’s center, and green shows gas that has been stripped out of satellite galaxies and enriched in metal content by supernova explosions.Found in "Baby Milky Way Modeled" online at: sciencenews.org/view/generic/id/45004/title/Baby_Milky_Way_modeled
Credit: B. Moore, Oscar Agertz and Romain Teyssier/University of Zurich
June 2009
10.06.09
First extragalactic exoplanet may have been found
Professor Philippe Jetzer of the University of Zürich in Switzerland and five colleagues simulated microlensing from the Andomeda galaxy.
An extrasolar planet may have been detected in nearby Andromeda
(Image: Bill Schoening, Vanessa Harvey/REU program/NOAO/AURA/NSF)
>> Read the article in New Scientist
>> BBC News article about the hints of the first planet to be spotted outside of our galaxy.
03.06.09
Talk by Professor Lawrence Krauss:
The Amazing Physics of Star Trek
January 2009
05.01.09
Press Release: First complete map of the Milky Way Galaxy
German version:
http://www.mediadesk.uzh.ch/mitteilung.php?text_id=352
English version:
http://www.public.iastate.edu/~nscentral/news/2008/dec/milkyway.shtml
>>> Radio interview on worldradio.ch (or download the mp3 file here.)
SF1 "10 vor 10" news broadcast:
November 2008
STUDIVERSUM 2008/11
Interview with P. Englmaier and P. Saha:
VOM ENDE VON RAUM UND ZEIT
October 2008
The Magellanic group and its seven dwarf galaxies
Astronomers at the University of Zurich have proposed a new theory for the formation of dwarf galaxies. In a paper published in 'The Astrophysical Journal,' Elena D'Onghia and George Lake solve several outstanding problems by comparing observed dwarfs to supercomputer simulations of their formation.
more >>>
September 2008
16.09.08
Press Release: A DARK MATTER DISK IN OUR GALAXY
An international team of scientists predict that our Galaxy, the Milky Way, contains a disk of 'dark matter'. In a paper published in Monthly Notices of the Royal Astronomical Society, astronomers Dr Justin Read, Professor George Lake and Oscar Agertz of the University of Zurich, and Dr Victor Debattista of the University of Central Lancashire use the results of a supercomputer simulation to predict the presence of this disk. They explain how it could allow physicists to directly detect and identify the nature of dark matter for the first time.
A composite image of the dark matter disk (red contours) and the Atlas Image mosaic of the Milky Way obtained as part of the Two Micron All Sky Survey (2MASS), a joint project of the University of Massachusettes and
the Infrared Processing and Analysis Center /California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation. Credit: J. Read & O.Agertz
>>High resolution figures and text
Press coverage:
Yahoo
Science Daily
Astronomy Now
Scientific Blogging
August 2008
24.08.08
How Do Galaxies Grow?
Assembling the Most Massive Galaxies in the Universe
Astronomers have caught multiple massive galaxies in the act of merging about 4 billion years ago. This discovery, made possible by combining the power of the best ground- and space-based telescopes, uniquely supports the favoured theory of how galaxies form.
ESO PR Photo 24/08
Merging Galaxies in Groups
How do galaxies form? The most widely accepted answer to this fundamental question is the model of 'hierarchical formation', a step-wise process in which small galaxies merge to build larger ones. One can think of the galaxies forming in a similar way to how streams merge to form rivers, and how these rivers, in turn, merge to form an even larger river. This theoretical model predicts that massive galaxies grow through many merging events in their lifetime. But when did their cosmological growth spurts finish? When did the most massive galaxies get most of their mass?
To answer these questions, astronomers study massive galaxies in clusters, the cosmological equivalent of cities filled with galaxies. "Whether the brightest galaxies in clusters grew substantially in the last few billion years is intensely debated. Our observations show that in this time, these galaxies have increased their mass by 50%," says Kim-Vy Tran from the University of Zürich, Switzerland, who led the research.
Read the entire press release here >>>
21.08.08
At the heart of darkness
In one of the world's largest supercomputer calculations, using over two million cpu hours on the Marenostrum supercomputer, we have carried out a high precision calculation of the structure of the Galactic dark matter halo.
The simulation evolves over three billion dark matter particles from the nearly smooth initial conditions observed in the microwave background, of which over a billion particles end up within the final halo, where we can resolve 100,000 orbiting substructures and thousands within the Galactic disk. At this resolution we can resolve the density profile to an unprecedented 100 parsecs from the Galactic centre and propose a simple new two parameter function to describe its radial distribution.
For further details you can download the first scientific paper here: http://arxiv.org/abs/0808.2981
and an ultra high resolution image of the simulation (shown below) here: caution, this is a 20,000x20,000 pixel 175 megabyte jpeg file! (Well worth the wait and best viewed with eog (under linux) "eye-of-gnome" and not within the browser!)
Click on the image above to view a movie showing the wealth of structure present in the GHALO simulation.
Figure 1. The dark matter distribution within the inner 200kpc of our Galactic halo |
Figure 2. The Marenostrum supercomputer in Barcelona where the calculation was carried out |
06.08.08
Spitzer Notices Star Birth Spike in Galaxies Moving to Cosmic Cities
New evidence from NASA's Spitzer Space Telescope reveals that most galaxies undergo a huge stellar baby boom when they first enter a "cosmic city", or galaxy cluster. And the more distant the galaxy cluster, the greater the star formation rate.
"The infrared Spitzer observations let us peek at otherwise hidden, powerful star formation harbored in some of these cluster galaxies," says Dr. Amelie Saintonge, of the Institute for Theoretical Physics, University of Zurich, in Switzerland. "By looking at both nearby and distant galaxy clusters, we can look back in time and observe an increase in the fraction of galaxies undergoing these intense star-forming events."
Sanitonge and Dr. Kim-Vy Tran, also of the University of Zurich, studied a total of 1,300 galaxies in eight clusters spread across 7 billion light-years. The galaxies were observed by Spitzer's Multiband Imaging Photometer (MIPS), and archived for the astronomical community to use.
Read more >>>
May 2008
Visiting Professor Lawrence M. Krauss
gave a public talk on May 19th, entitled
"Our Miserable Future: Life, the Universe and Nothing."
An article from the Uni public magazine can be found here:
http://www.unipublic.unizh.ch/magazin/umwelt/2008/2973.html
April 2008
The "MNF Event" at the University of Zürich's 175th Anniversary Celebration was a great success!
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Researchers at the Institute for Theoretical Physics share secrets of the universe with the general public in celebration of the 175th anniversary of the University of Zurich.
Posters
All posters printed in B1 format!
Treasure Hunt posters: Sun, Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto.
February 2007
Darkest of the dark
Dwarf spheroidal galaxies are dominated by dark matter, and within their ranks Draco, Ursa Minor and Andromeda X are 'darkest'. None of the models so far proposed to explain their formation can account for both their exceptional dark matter content and their proximity to a much larger galaxy. Mayer et al. now report simulations showing that their progenitors were probably gas-dominated dwarf galaxies that became satellites of a larger galaxy earlier than the other dwarf spheroidals. Tidal shocks and ram pressure stripped all the gas from the progenitors about 10 billion years ago, leaving a tiny stellar component in a more massive dark halo, which is what we see today. The paper is "Early gas stripping as the origin of the darkest galaxies in the Universe".
Figure 1 - Morphological evolution of the dwarf galaxy satellite. Follow link below for further information.
View the full paper
Watch the movie
Links:
Unipublic Magazine
Science ORF Austria
Sciam.com
Sciencedaily.com
BBC News
August 2006
Scientists Use Bent Light to Measure the Universe
Scientists in Switzerland and the United States have confirmed the age and expansion rate of the universe using a promising and relatively new technique independent of the methods most commonly used.
Their technique is based on gravitational lensing, or the way light can bend around a galaxy. This technique has provided measurements consistent with those found by other methods. With more data, the scientists say, this could offer the most precise means to measure these most basic yet important parameters of the universe.
Download the entire press release in English: PDF File (14 KB), 
Text File
Download the entire press release in German: PDF File (16 KB), Text File
>> View the Swiss TV SF1 broadcast (Realplayer video)
February 2006
New Research Professorships at the University of Zurich
Steen Hansen, Lucio Mayer and Vy Tran were awarded prestigious four year professorships funded by the Swiss National Science Foundation to carry out independent research in Astrophysics at the University.
>>> more
February 2006
Superstar, Andrea Maccio wins jackpot on Zerovero
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Ask Andrea for details on how he won the 2nd largest jackpot in Swiss tv history... !
January 2005 - slashdotted:
We were featured on slashdot and had one million hits in 3 days.
January 2005
Before Stars, Dark Matter Haloes were First Objects in the Early Universe
Ghostly haloes of dark matter as heavy as the earth and as large as our solar system were the first structures to form in the universe, according to new calculations from scientists at the University of Zurich, published in this week's issue of Nature.
Download the entire press release in English: PDF File (22 KB), Text File
Download the entire press release in German: PDF File (22 KB), Text File
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Figure 1. The predicted distribution of dark matter in the universe. Galaxies form within the complex network of massive filamentary dark matter structures. The region shown below is a billion light years across. |
Figure 2. A zoom into the first object to form in the universe. The two inset regions are each expanded by a scale of a hundred, starting from the 10,000 light year across entire blue region into the single earth mass dark matter structure which has a size of the size of the solar system. |
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| Figure 3. The distribution of dark matter surrounding the Milky Way. Numerous smaller dark matter haloes can be seen in this image which is the result of a six month computer calculation. |
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