Sorry! Omdat deze pagina niet beschikbaar is in de taal van uw voorkeur tonen wij de originele pagina.
Page saved successfully
Couldn't save page :( Please try again.
SINFONI
Spectrograph for INtegral Field Observations in the Near Infrared
Go to Unit Telescope 4 (UT4, Yepun) of the Very Large Telescope (VLT) at the Paranal Observatory and SINFONI can be found conducting its own beautiful observational orchestra, thanks to its two component instruments working together: SPIFFI (SPectrometer for Infrared Faint Field Imaging), which is an infrared integral field spectrograph, and the SINFONI-AO (adaptive optics) module. George Hau and Bin Yang are responsible for arranging SINFONI’s harmony with the stars.
An integral field spectrograph (IFS) allows you to observe in three dimensions across the entirety of an astronomical object in one go: each pixel of the image is associated with a full spectrum, measuring the intensity of the light at each wavelength (the wavelength is a measurement of its colour — in some objects, it can be converted into a velocity towards or away from the Earth and tells us about its relative position in space as a result.
SINFONI uses an “image slicer” technique: as shown in the figure below, a two-dimensional image (a) is chopped into smaller components (via “optical slicing”) and re-positioned by special segmented mirrors so that they lie in a line end-to-end instead of on top of each other (b). This essentially forms a very long virtual slit. The light from the virtual slit is split by SPIFFI into its separate colours and therefore wavelengths (c), and the image is then reconstructed from the individual slices at each wavelength, i.e. the image is reconstructed from all the slices at the red end of the spectrum, then the green, etc. They are then combined to give us the final, 3D information we desire (d).
Traditional methods of obtaining spectra over the full extent of a large, extended object is both time consuming and inefficient — an IFS solves both of these problems. SINFONI is therefore the ideal instrument for looking at some of the most interesting galaxies and planetary nebulae in the Universe. Because SINFONI only uses mirrors, it can be cooled to extremely low temperatures (between -150 and -273 degrees C, or “cryogenic temperatures”). This, combined with the adaptive optics module SINFONI-AO, which also works better towards the red end of the spectrum, means that overall SINFONI is tailored for observing at infrared wavelengths.
Thanks to SINFONI-AO, the instrument can also correct for atmospheric turbulence. The distorted image of a guide star is used to measure the effect of the turbulence, and a small, deformable mirror adjusts itself in real time to correct for these distortions. For the cases where a reference star is not available, the Laser Guide Star (LGS) can be used to create a bright spot 80 kilometres above the telescope and this is used as an artificial reference star. As a result, the images reaching SPIFFI are almost as sharp as if there were no atmosphere above the VLT at all — music to our ears!
Science highlights with SINFONI
Discovery that early Universe galaxies were dominated by normal, rather than dark, matter (eso1709)
Discovery of by far the brightest galaxy yet found in the early Universe and strong evidence found that examples of the first generation of stars lurk within it (eso1524)
SINFONI was used to help reveal that three billion years after the Big Bang, giant eliptical galaxies still make stars in their outskirts, but no longer in their interiors (eso1516)
Best view yet of dusty cloud (G2) passing galactic centre black hole (eso1512)
SINFONI was used to gather the best direct observational evidence so far supporting the theory that galaxies pull in and devour nearby material in order to grow and form stars (eso1330)
A giant gas cloud is being ripped apart by the supermassive black hole at the centre of the Milky Way; SINFONI has been studying the cloud’s fate (eso1151, eso1332). Before that, SINFONI observed the motion of stars surrounding the black hole, which were used to measure how far away it is and its mass. (eso0846).
SINFONI has made many observations to study the growth and evolution of galaxies in a distant past: at the beginning, they tended to gently snack on nearby gas (eso1040, eso1330), but at a later stage in their growth, they would cannibalise other, smaller galaxies. (eso1212)
The most distant galaxy ever measured to date was observed by SINFONI as it was only 600 million years after the Big Bang. (eso1041)
A raw image obtained with SINFONI. The image slicer chopped the image of a small region of the sky into a series of 32 narrow slices, and aligned them at the entrance of the spectrograph. The spectrograph then spread the light into its individual colours, forming a spectrum of each slice. Here, the 32 spectra of the individual slice appear as vertical bands. Each slice is slightly vertically offset from its neighbours. Complex data-processing software is required to re-assemble the information contained here into a full 3D spectral image.
SINFONI
The authoritative technical specifications as offered for astronomical observations are available from the Science Operation page.
High spatial and spectral resolution studies of compact objects (star-forming regions, nuclei of galaxies, cosmologically distant galaxies, galactic centre).
Consortium:
Max Planck Institute for Extraterrestrische Physik (MPE), Garching, Germany
Nederlandse Onderzoekschool Voor Astronomie (NOVA) in Leiden, the Netherlands
The Netherlands Foundation for Research in Astronomy (ASTRON), the Netherlands
ESO
Our use of Cookies
We use cookies that are essential for accessing our websites and using our services. We also use cookies to analyse, measure and improve our websites’ performance, to enable content sharing via social media and to display media content hosted on third-party platforms.
You can manage your cookie preferences and find out more by visiting 'Cookie Settings and Policy'.
ESO Cookies Policy
The European Organisation for Astronomical Research in the Southern Hemisphere (ESO) is the pre-eminent intergovernmental science and technology organisation in astronomy. It carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities for astronomy.
This Cookies Policy is intended to provide clarity by outlining the cookies used on the ESO public websites, their functions, the options you have for controlling them, and the ways you can contact us for additional details.
What are cookies?
Cookies are small pieces of data stored on your device by websites you visit. They serve various purposes, such as remembering login credentials and preferences and enhance your browsing experience.
Categories of cookies we use
Essential cookies (always active): These cookies are strictly necessary for the proper functioning of our website. Without these cookies, the website cannot operate correctly, and certain services, such as logging in or accessing secure areas, may not be available; because they are essential for the website’s operation, they cannot be disabled.
Cookie ID/Name
Description/Purpose
Provider (1st party or 3rd party)
Browser session cookie or Stored cookie?
Duration
csrftoken
XSRF protection token. We use this cookie to protect against cross-site request forgery attacks.
1st party
Stored
1 year
user_privacy
Your privacy choices. We use this cookie to save your privacy preferences.
1st party
Stored
6 months
_grecaptcha
We use reCAPTCHA to protect our forms against spam and abuse. reCAPTCHA sets a necessary cookie when executed for the purpose of providing its risk analysis. We use www.recaptcha.net instead of www.google.com in order to avoid unnecessary cookies from Google.
3rd party
Stored
6 months
Functional Cookies: These cookies enhance your browsing experience by enabling additional features and personalization, such as remembering your preferences and settings. While not strictly necessary for the website to function, they improve usability and convenience; these cookies are only placed if you provide your consent.
Cookie ID/Name
Description/Purpose
Provider (1st party or 3rd party)
Browser session cookie or Stored cookie?
Duration
Settings
preferred_language
Language settings. We use this cookie to remember your preferred language settings.
1st party
Stored
1 year
ON | OFF
sessionid
ESO Shop. We use this cookie to store your session information on the ESO Shop. This is just an identifier which is used on the server in order to allow you to purchase items in our shop.
1st party
Stored
2 weeks
ON | OFF
Analytics cookies: These cookies collect information about how visitors interact with our website, such as which pages are visited most often and how users navigate the site. This data helps us improve website performance, optimize content, and enhance the user experience; these cookies are only placed if you provide your consent. We use the following analytics cookies.
Matomo Cookies:
This website uses Matomo (formerly Piwik), an open source software which enables the statistical analysis of website visits. Matomo uses cookies (text files) which are saved on your computer and which allow us to analyze how you use our website. The website user information generated by the cookies will only be saved on the servers of our IT Department. We use this information to analyze www.eso.org visits and to prepare reports on website activities. These data will not be disclosed to third parties.
On behalf of ESO, Matomo will use this information for the purpose of evaluating your use of the website, compiling reports on website activity and providing other services relating to website activity and internet usage.
ON | OFF
Matomo cookies settings:
Cookie ID/Name
Description/Purpose
Provider (1st party or 3rd party)
Browser session cookie or Stored cookie?
Duration
Settings
_pk_id
Stores a unique visitor ID.
1st party
Stored
13 months
_pk_ses
Session cookie temporarily stores data for the visit.
1st party
Stored
30 minutes
_pk_ref
Stores attribution information (the referrer that brought the visitor to the website).
1st party
Stored
6 months
_pk_testcookie
Temporary cookie to check if a visitor’s browser supports cookies (set in Internet Explorer only).
1st party
Stored
Temporary cookie that expires almost immediately after being set.
Additional Third-party cookies on ESO websites: some of our pages display content from external providers, e.g. YouTube.
Such third-party services are outside of ESO control and may, at any time, change their terms of service, use of cookies, etc.
YouTube: Some videos on the ESO website are embedded from ESO’s official YouTube channel. We have enabled YouTube’s privacy-enhanced mode, meaning that no cookies are set unless the user actively clicks on the video to play it. Additionally, in this mode, YouTube does not store any personally identifiable cookie data for embedded video playbacks. For more details, please refer to YouTube’s embedding videos information page.
Cookies can also be classified based on the following elements.
Regarding the domain, there are:
First-party cookies, set by the website you are currently visiting. They are stored by the same domain that you are browsing and are used to enhance your experience on that site;
Third-party cookies, set by a domain other than the one you are currently visiting.
As for their duration, cookies can be:
Browser-session cookies, which are deleted when the user closes the browser;
Stored cookies, which stay on the user's device for a predetermined period of time.
How to manage cookies
Cookie settings: You can modify your cookie choices for the ESO webpages at any time by clicking on the link Cookie settings at the bottom of any page.
In your browser: If you wish to delete cookies or instruct your browser to delete or block cookies by default, please visit the help pages of your browser:
Please be aware that if you delete or decline cookies, certain functionalities of our website may be not be available and your browsing experience may be affected.
You can set most browsers to prevent any cookies being placed on your device, but you may then have to manually adjust some preferences every time you visit a site/page. And some services and functionalities may not work properly at all (e.g. profile logging-in, shop check out).
Updates to the ESO Cookies Policy
The ESO Cookies Policy may be subject to future updates, which will be made available on this page.
Additional information
For any queries related to cookies, please contact: pdprATesoDOTorg.
As ESO public webpages are managed by our Department of Communication, your questions will be dealt with the support of the said Department.
Go to Unit Telescope 4 (UT4, Yepun) of the Very Large Telescope (VLT) at the Paranal Observatory and SINFONI can be found conducting its own beautiful observational orchestra, thanks to its two component instruments working together: SPIFFI (SPectrometer for Infrared Faint Field Imaging), which is an infrared integral field spectrograph, and the SINFONI-AO (adaptive optics) module. George Hau and Bin Yang are responsible for arranging SINFONI’s harmony with the stars.
SINFONI uses an “image slicer” technique: as shown in the figure below, a two-dimensional image (a) is chopped into smaller components (via “optical slicing”) and re-positioned by special segmented mirrors so that they lie in a line end-to-end instead of on top of each other (b). This essentially forms a very long virtual slit. The light from the virtual slit is split by SPIFFI into its separate colours and therefore wavelengths (c), and the image is then reconstructed from the individual slices at each wavelength, i.e. the image is reconstructed from all the slices at the red end of the spectrum, then the green, etc. They are then combined to give us the final, 3D information we desire (d).