Die Existenz dieses Moleküls im All wurde bereits in den 1970er Jahren vorhergesagt und konnte nun erstmals nachgewiesen werden
Das James Webb-Weltraumteleskop hat das Kohlenwasserstoffmolekül CH3+ in einem 1500 Lichtjahre entfernten, neu entstehenden Sonnen- und Planetensystem entdeckt. CH3+ ist ein elementares Kohlenwasserstoffmolekül, das zwar nicht mit dem überall vorkommenden Wasserstoff (H2), dafür aber mit anderen Molekülen reagiert und somit zur Bildung sehr viel komplexerer Moleküle im Weltall beitragen kann.
Verschiedene Gruppen am Kölner Institut für Astrophysik haben zum aktuellen Forschungsergebnis beigetragen, auch durch den Bau einiger JWST-Spektrometer-komponenten (AG Professor Dr. Andreas Eckart). Ein anderes Team, die Kölner Submillimeter-Astrophysik Gruppe, untersucht seit langem die Physik und Chemie des Orionnebels. Die Beobachtungen mit dem JWST wurden von Privatdozent Dr. Markus Röllig und Dr. Yoko Okada mitentworfen und -ausgewertet.
Experimente der Laborastrophysikgruppe (AG Professor Dr. Stephan Schlemmer) machten es möglich, CH3+ zu identifizieren. Die Gruppe beschäftigt sich mit Molekülspektroskopie, bei der sie die spektralen Fingerabdrücke der Moleküle im Labor im Radio- und Infrarotbereich misst, ohne die eine Identifizierung im Weltall nicht möglich wäre. Das CH3+ Molekül wurde schon 2018 unter der Leitung von Professor Schlemmer und Privatdozent Dr. Oskar Asvany in einer sogenannten kalten Ionenfalle untersucht.
Inhaltlicher Kontakt:
Professor Dr. Stephan Schlemmer
Institut für Astrophysik
+49 221 470 7880
schlemmerph1.uni-koeln.de
Presse und Kommunikation:
Jan Voelkel
+49 221 470 2356
j.voelkelverw.uni-koeln.de
Weitere Informationen:
https://esawebb.org/news/weic2315/
New CRC 1601
The University of Cologne has obtained a new Collaborative Research Center (CRC) from the German Research Foundation (DFG). In addition, two existing CRCs have been extended. The new CRC 1601 is entitled "Habitats of Massive Stars across Cosmic Time". The CRC will be funded for four years. The spokesperson of the new Collaborative Research Center is astronomy professor Dr. Stefanie Walch-Gassner from the Institute of Astrophysics at the University of Cologne. The researchers are investigating the cosmic evolution of the habitats of massive stars - the gaseous environments in which these stars are born and with which they interact. Due to their short lifetimes and high energy output, massive stars have significantly influenced the evolution of galaxies since the beginning of the universe.
Within the CRC 1601, researchers are investigating the physical processes that determine the habitats of massive stars in different galactic environments. The new CRC combines four pillars: laboratory astrophysics, instrument development, observations, and theoretical modeling and simulations. The CRC partners have a strong profile as leading players in large international projects and have extensive experience in building and operating their own telescopes and developing state-of-the-art instruments in the infrared, submillimeter, and radio wave ranges. New developments, in particular the launch of the FYST/CCAT telescope in 2024, in which the Universities of Cologne and Bonn have a 25 percent stake, will be optimally supported by CRC 1601.
"We are extremely pleased about the new establishment of CRC 1601. The funding enables us to pursue an integrative approach. By combining the four pillars, we will be able to close major gaps in our understanding," said Professor Dr. Walch-Gassner. "High-resolution studies of the habitats of massive stars will be combined with studies that look at the entire system 'galaxy.' This, and the inclusion of novel studies of the early universe and the associated extreme and highly variable conditions that prevail in young galaxies, will enable us to understand and quantify the cosmic evolution of the habitats of massive stars."
Jan Voelkel
+49 221 470 2356
j.voelkel @verw.uni-koeln.de
25 years ago, in May 1998, the first two CDMS entries appeared online. Initially only intended as a supplement, the CDMS has evolved into the most important resource of spectroscopic data of molecules of interest for radio astronomy in a wider sense.
The entries are generated from experimental data, usually from laboratory spectroscopy, but also from astronomical observations, using established Hamiltonian models. The astronomical community appreciates very much that experimental data as well as Hamiltonian models are critically evaluated. Separate entries exist for isotopic species and usually also for excited vibrational states. The CDMS catalog has been instrumental in numerous detections of molecular species in space.
As of today, there are 1195 different entries in the CDMS catalog, of which as least 505 have been detected securely or nearly so. These 505 species represent a large fraction of the approximately 300 different molecules that have been detected in the interstellar medium or in the circumstellar envelopes of late-type stars, as can also be seen on one of the classical CDMS pages.
The CDMS has been a member of the Virtual Atomic and Molecular Data Centre (VAMDC) consortium for many years.
The William F. Meggers Award 2023 was presented to Stephan Schlemmer for pioneering ultra-sensitive action spectroscopy with fundamental applications to spectra of molecular ions, particularly CH5+, and their key roles in astrochemistry.
The award was established in 1970 to honor William Meggers for his notable contributions to the field of spectroscopy and metrology. It is endowed by the family of William Meggers, several individuals, and a number of optical manufacturers.
Stephan Schlemmer received his Ph.D. from the University of Göttingen, Germany and was a postdoctoral fellow at the University of California, Berkeley, USA and Universita di Perugia, Italy. He is currently a professor of experimental physics at Universität zu Köln. He has also held positions at Leiden University, Netherlands and Chemnitz University of Technology, Germany
He specializes in molecular physics with an emphasis on high-resolution IR and THz spectroscopy, reaction dynamics, astrophysics, and astrochemistry. He pioneered the development of several novel spectroscopy tools and utilized them to address long standing spectroscopic problems.
One of Schlemmer’s major contributions to the field was his invention of action spectroscopy, which enables ion spectroscopy to be conducted with unparalleled sensitivity and resolution.
New observations have brought to light that stars can form through the dynamic interaction of gas within interstellar gas clouds. This process unfolds faster than previously assumed, research within the FEEDBACK programme on board the flying observatory SOFIA revealed.
Gas clouds in the Cygnus X Region, a region where stars form, are composed of a dense core of molecular hydrogen (H2) and an atomic shell. These ensembles of clouds interact with each other dynamically in order to quickly form new stars. That is the result of observations conducted by an international team led by scientists at the University of Cologne’s Institute of Astrophysics and at the University of Maryland. Until now, it was unclear how this process precisely unfolds. The Cygnus X region is a vast luminous cloud of gas and dust approximately 5,000 light years from Earth. Using observations of spectral lines of ionized carbon (CII), the scientists showed that the clouds have formed there over several million years, which is a fast process by astronomical standards. The results of the study ‘Ionized carbon as a tracer for the assembly of interstellar clouds’ will appear in the next issue of Nature Astronomy. The paper is already accessible online.
The observations were carried out in an international project led by Dr Nicola Schneider at the University of Cologne and Prof Alexander Tielens at the University of Maryland as part of the FEEDBACK programme on board the flying observatory SOFIA (Stratospheric Observatory for Infrared Astronomy). The new findings modify previous perceptions that this specific process of star formation is quasi-static and quite slow. The dynamic formation process now observed would also explain the formation of particularly massive stars.
By comparing the distribution of ionized carbon, molecular carbon monoxide and atomic hydrogen, the team found that the shells of interstellar gas clouds are made of hydrogen and collide with each other at speeds of up to twenty kilometres per second. “This high speed compresses the gas into denser molecular regions where new, mainly massive stars form. We needed the CII observations to detect this otherwise ‘dark’ gas,” said Dr Schneider. The observations show for the first time the faint CII radiation from the periphery of the clouds, which could not be observed before. Only SOFIA and its sensitive instruments were capable of detecting this radiation.
SOFIA was operated by NASA and the German Aerospace Center (DLR) until September 2022. The observatory consisted of a converted Boeing 747 with a built-in 2.7-metre telescope. It was coordinated by the German SOFIA Institute (DSI) and the Universities Space Research Association (USRA). SOFIA observed the sky from the stratosphere (above 13 kilometres) and covered the infrared region of the electromagnetic spectrum, just beyond what humans can see. The Boeing thus flew above most of the water vapour in the Earth’s atmosphere, which otherwise blocks out infrared light. This allowed the scientists to observe a wavelength range that is not accessible from Earth. For the current results, the team used the upGREAT receiver installed on SOFIA in 2015 by the Max Planck Institute for Radio Astronomy in Bonn and the University of Cologne.
Even though SOFIA is no longer in operation, the data collected so far are essential for basic astronomical research because there is no longer an instrument that extensively maps the sky in this wavelength range (typically 60 to 200 micrometres). The now active James Webb Space Telescope observes in the infrared at shorter wavelengths and focuses on spatially small areas. Therefore, the analysis of the data collected by SOFIA is ongoing and continues to provide important insights – also regarding other star-forming regions: “In the list of FEEDBACK sources, there are other gas clouds in different stages of evolution, where we are now looking for the weak CII radiation at the peripheries of the clouds to detect similar interactions as in the Cygnus X region,” Schneider concluded.
Press and Communications Team: Jan Voelkel
Understanding more precisely how stars form from interstellar molecular clouds is one of the most pressing astrophysical questions. NASA's James Webb Space Telescope is now providing spectacular new images of the Orion Nebula, a very active birthplace of young stars in our immediate neighborhood.
Together with an international team of experts, researchers from the I. Physikalisches Institut of the University of Cologne (Yoko Okada and Markus Röllig ) had their first look at the new images. In the coming weeks, they will analyze the data more deeply to decipher the details of star formation in Orion.
An enormous hole 22 meters in diameter has been dug near the summit of Cerro Chajnantor in Chile’s Atacama Desert, at an elevation of 18,400 feet. The hole stands ready for the cement foundation on which the Fred Young Submillimeter Telescope (FYST, pronounced “feest”) will one day rest. The foundation, which was designed in Chile, began construction in the fall of 2021 and is scheduled to be installed at the summit from May to June.
Rotational action spectroscopy is an experimental method in which rotational spectra of molecules,
typically in the microwave to sub-mm-wave domain of the electromagnetic spectrum (B1–1000 GHz),
are recorded by action spectroscopy. Action spectroscopy means that the spectrum is recorded not by
detecting the absorption of light by the molecules, but by the action of the light on the molecules, e.g.,
photon-induced dissociation of a chemical bond, a photon-triggered reaction, or photodetachment of
an electron. Typically, such experiments are performed on molecular ions, which can be well controlled
and mass-selected by guiding and storage techniques. Though coming with many advantages, the application of action schemes to rotational spectroscopy was hampered for a long time by the small energy content of a corresponding photon. Therefore, the first rotational action spectroscopic methods
emerged only about one decade ago. Today, there exists a toolbox full of different rotational action
spectroscopic schemes which are summarized in this review.
During an internship of guest student Julian Fischer, measurements were made at the I. Physikalisches Institut in the working group of Prof. Schlemmer.
The result: a signal reminiscent of the Cologne Cathedral ... which even occurs at 111 GHz.
Normally, the group measures and studies the spectroscopic fingerprints of molecules (especially with astrophysical relevance). Molecules have, comparable to humans, unique fingerprints by which they can be identified. Therefore, molecules in distant galaxies, star forming regions, etc. can be detected by these signatures.
HRMS 2021
In August 2021 we have organized the 27th Colloquium on High-Resolution Molecular Spectroscopy with more than 250 online participants in Cologne.
The 27 th Colloquium on High-Resolution Molecular Spectroscopy (HRMS) was initially planned on-site. Due to the Covid-19 pandemic, the event was held for the first time as an online conference to fulfill the regulations of the government and to facilitate safe exchange of scientific information.
There were 11 invited lectures and 3 mini-symposia. Parallel sessions featured 54 contributed lectures given by PhD students and postdocs. The scientific fields covered were:
- High resolution rotational, vibrational, and electronic spectroscopy of molecules (radicals, ions, complexes, clusters, ...)
- Molecular dynamics
- Theory assisting the prediction, simulation, and interpretation of spectra
- New techniques for high-resolution spectroscopy
- Applications to atmospheric sciences, astrophysics, planetology, combustion, gas-phase biomolecules, metrology and fundamental physics, cold molecules, etc.
As in previous years, a special issue of the journal "Molecular Physics" was published to mark the HRMS 2021 conference and to celebrate the 75th birthday of Dr. Jean-Marie Flaud.
On August 29, 2021, Professor Melanie Schnell (Deutsches Elektronen Synchrotron in Hamburg) and Prof. Stephan Schlemmer (University of Cologne) were honored at the 27th Colloquium on High Resolution Molecular Spectroscopy in Cologne.
Professor Melanie Schnell was awarded for her studies on structural changes in water complexes with increasing numbers of water molecules and for her pioneering work on the spectroscopic discrimination of enantiomers and the separation of these chirally distinct molecules.
Professor Stephan Schlemmer received the award for his pioneering work on high-resolution spectroscopic studies of molecular ions using light-induced reactions in ion traps, in particular for his studies on the extremely flexible methanium ion CH5+, which plays a key role in chemistry but also in space exploration.
In memory of the founder, the Foundation has awarded the international Doctor Barbara Mez-Starck Prize annually since 2003 for outstanding contributions in the field of high-precision experimental structural chemistry and molecular physics (including gas electron diffraction, microwave and high-resolution infrared spectroscopy). The prize is endowed with up to €5000. Nominations come from eminent researchers in these fields.
Large-scale [CII] mapping provides new insight into the kinematics of the ISM. The interaction between massive stars and the ISM is probed through [CII] observations. Spectrally resolving the [CII] emission is necessary to probe the microphysics induced by the feedback of massive stars. We show that certain heterodyne instrument data quality issues can be resolved using a spline-based technique, and better data correction routines allow for more efficient observing strategies.
The present Virtual Special Issue (VSI), ”Laboratory Spectroscopy for Astrophysics”, celebrates Stephan Schlemmer’s remarkable contributions to the field of molecular spectroscopy, molecular collisions, and laboratory astrophysics over the last three decades, on the occasion of his 60th birthday on September 7, 2020. This VSI, guest edited by three of the authors (P. J., J. O. and H. M.), contains contributions covering all relevant forms of molecular spectroscopy, in particular involving laboratory astrophysics in the microwave, infrared or XUV part of the spectrum, at high or low resolution.
The German-French programme GENESIS (Generation of Structures in the Interstellar Medium) is a cooperation between the University of Cologne’s Institute for Astrophysics, LAB at the University of Bordeaux and Geostat/INRIA Institute Bordeaux. In a highlight publication of the journal Astronomy & Astrophysics, the research team presents the new mathematical methods to characterize turbulence using the example of the Musca molecular cloud in the constellation of Musca.
Die Hülle eines S-Sterns
Sagittarius A*, das extrem massereiche Schwarze Loch im Zentrum unseres Milchstraßensystems, umkreisen auf engen Bahnen mehrere Dutzend Sterne – die Mitglieder des S-Sternhaufens. Einer von ihnen, der Stern S 50, ist mit einer länglichen Struktur mit der Bezeichnung X 7 verknüpft. Um was handelt es sich dabei?
More than a hundred people gathered virtually at the end of April for the 2021 annual conference on the CCAT-prime project, which is building the Fred Young Submillimeter Telescope (FYST) in Chile. Despite pandemic challenges, telescope planning, development and construction continues, with “first light” now scheduled for 2023.
Der Europäische Forschungsrat (ERC) hat die beiden Kölner Wissenschaftler Professor Dr. Michael Bollig und Professor Dr. Stephan Schlemmer mit dem ERC Advanced Grant ausgezeichnet. Bollig wird für sein Projekt REWILDING mit knapp 2,5 Millionen Euro gefördert. Schlemmer erhält für sein Projekt „MissIons“ ebenfalls Fördergelder in Höhe von 2,5 Millionen Euro. Der ERC Advanced Grant gilt als der wichtigste Förderpreis der europäischen Forschungslandschaft.
Am Südhimmel, etwa 4.300 Lichtjahre von der Erde entfernt, liegt RCW 120, eine riesige leuchtende Wolke aus Gas und Staub. Ein internationales Team, das hauptsächlich von Forschern und Forscherinnen der Universität Köln und der West Virginia University (USA) geleitet wurde, konnte das Alter von RCW 120 auf weniger als 150.000 Jahre eingrenzen, was sehr jung für einen solchen Nebel ist. Die Untersuchungen ergaben, dass die stellare Rückkopplung – ein Prozess, bei dem Sterne Energie zurück in ihre Umgebung abgeben – die Sternbildung in der Umgebung positiv beeinflusst. Diese Erkenntnisse können Aufschluss über die hohe Rate an Sternentstehungen im frühen Stadium unseres Universums geben. Die Ergebnisse dieser Studie sind in der April-Ausgabe der Zeitschrift Science Advances veröffentlicht (Luisi et al. 2021).
Die fliegende Sternwarte SOFIA (das Stratosphären-Observatorium Für Infrarot-Astronomie) hat eine Reihe von Beobachtungsflügen vom Flughafen Köln/Bonn aus erfolgreich abgeschlossen. Mit an Bord waren Wissenschaftlerinnen und Wissenschaftler der Uni Köln und des MPI für Radioastronomie in Bonn, die weitere Erkenntnisse zur Entstehung von neuen Sternen gewinnen konnten
Hoch in den Bergen Chiles, auf dem 5.600 Meter hohen Cerro Chajnantor in der Atacama-Wüste, befindet sich einer der trockensten Orte der Erde. Mithilfe des neu entstehenden Fred Young Submillimeter Telescope (FYST) erhoffen sich Astronomen neue Einblicke in die Entstehung der Sterne und Galaxien in unserem Universum. Forscher und Forscherinnen der Universität zu Köln unter Leitung von Professor Dr. Jürgen Stutzki sind an dem internationalen Konsortium von Wissenschaftlern beteiligt. Durch die Finanzierung der kanadischen Kooperationspartner mit 4,9 Millionen Dollar durch die Canada Foundation for Innovation ist das Projekt jetzt auf sichere Füße gestellt.