Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Galaxy Collision Debris a Laboratory to Study Star Formation

05.06.2008
Researchers have shown that the process of star formation in areas of debris formed when two galaxies collide is essentially the same as star formation inside galaxies, meaning that the intergalactic medium can be a used as a simpler, more accessible laboratory for the study of stellar evolution.

An international team of researchers led by Médéric Boquien of the University of Massachusetts Amherst has shown that debris formed when two galaxies collide makes a simpler, more accessible laboratory for studying the process of star formation. The team presented their results at a press conference Monday, June 2 at the American Astronomical Society meeting in St. Louis, Missouri.

“Surprisingly, we found that star formation is essentially the same in galaxies and in the debris which occurs between galaxies, in spite of tremendous differences in the environment,” says Boquien, a post-doctoral researcher in the astronomy department. “This is a very exciting result, meaning that we can use these regions, which are located outside a pre-existing stellar disk and are much simpler than star forming regions in galaxies, to study the creation of stars.”

Additional members of the team include Pierre-Alain Duc of the National Center for Scientific Research in France, Frédéric Bournaud of the French Atomic Energy Commission, Jonathan Braine of the Bordeaux Observatory, Vassilis Charmandaris of the University of Crete, Greece and Ute Lisenfeld at the University of Granada, Spain.

Collision debris is the remains of a collision between two or more galaxies, in which the interplay of gravity can create long expanding “tidal tails.” This debris, which is ejected into the intergalactic medium located between galaxies, is composed mainly of gas and dust stripped from their parent galaxies. They can be as heavy as several billion suns, and serve as a reservoir that feeds star formation. The most massive of these star forming regions, called tidal dwarf galaxies, can be bound by their own gravity and rotate.

Barely studied since their discovery in the 1950s, these areas have sparked increasing interest from astronomers, and were recently used to test the nature of dark matter. What was not known was whether star formation was the same in collision debris as it was in galaxies, a key factor in determining their usefulness in the study of star formation.

To answer this question, Boquien and his team observed a carefully selected sample of six interacting galaxy systems located a distance of 55 to 375 million light years from Earth. The study focused on extreme systems in which a large fraction (up to 85%) of star formation takes place in collision debris, rather than in the main body of the parent galaxies, a situation that is representative of the distant, young Universe.

By simultaneously analyzing multiple wavelengths of emissions, including infrared radiation from the dust heated by young stars picked up by the Spitzer space observatory, the team was able to trace star formation and determine that the process was occurring in essentially the same way in the intergalactic medium and inside galaxies. Ultraviolet energy detected by the Galaxy Evolution Explorer and images of ionized hydrogen atoms and optical and infrared light from eight ground-based telescopes were also used.

“The best regions to study stellar evolution would be those completely devoid of old stars, and we were able to find some regions which satisfy this criteria,” says Boquien, who adds that these regions are generally quite isolated, unlike star forming regions in galaxies which can be surrounded by many bright astronomical objects. “As star formation apparently occurs in a similar way in galaxies, results we obtain studying intergalactic star forming regions can be confidently extended to galaxies.”

Médéric Boquien | newswise
Further information:
http://www.astro.umass.edu

More articles from Physics and Astronomy:

nachricht Water without windows: Capturing water vapor inside an electron microscope
13.12.2017 | Okinawa Institute of Science and Technology (OIST) Graduate University

nachricht Columbia engineers create artificial graphene in a nanofabricated semiconductor structure
13.12.2017 | Columbia University School of Engineering and Applied Science

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

A whole-body approach to understanding chemosensory cells

13.12.2017 | Health and Medicine

Water without windows: Capturing water vapor inside an electron microscope

13.12.2017 | Physics and Astronomy

Cellular Self-Digestion Process Triggers Autoimmune Disease

13.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>