The Accelerating Physics of the Universe Survey (PAUS), an international collaboration of 14 institutions, covered a 50-degree area of ​​the sky similar to approximately 250 full moons. Using the specially designed PAUCam camera on the 4.2-meter William Herschel Telescope (WHT) in La Palma, Spain, he was able to determine distances to galaxies with unprecedented precision. This included galaxies 10 billion light years away.

Surveys of distant galaxies are of two types: photometric surveys, which take high-precision images of the sky and capture any astronomical objects bright enough to be detected in those images, and spectroscopic surveys, which target and study a spectrum of known light sources. that is, the distribution of light over a wide range of wavelengths.

This mode is limited in the number of galaxies that can be observed and how faint they can be, but it provides a large amount of information about each galaxy. Collaborator Professor Benjamin Joachim, from UCL’s Department of Physics and Astronomy, explained that PAUS “combines the advantages of photometric and spectroscopic studies”.

He said: “We take and therefore record images of all visible objects in the sky, but we do this by placing narrow wavelength filters on the camera so we know that the light we collect comes from a particular part of the spectrum. Using 40 such filters we can reconstruct a low-resolution version of the galaxy spectrum.”

“The research will allow us to investigate how galaxies are connected to their surroundings, which are mostly made up of dark matter, and to understand how far away galaxies of certain types and luminosities are located, which will help us conduct more precise scientific studies where we do not have this information.”

The new catalog will allow astronomers to create more accurate maps to understand how the structure of the universe is formed and to study the expansion of the universe under the influence of dark matter and dark energy. Dark energy is believed to make up about 70% of the universe and is responsible for the rapid expansion of the universe, but its nature remains a mystery.

The collaboration was led by the Institute of Space Sciences (ICE-CSIC) with the support of the Spanish Ministry of Science, Innovation and Universities. Data was collected over 200 nights between 2015 and 2019. The catalog is available on the PAUS website and the CosmoHub portal.

Professor Enrique Gaztañaga, director of PAU Research based at the University of Portsmouth, ICE-CSIC and the Instituto de Esquisas de Catalunya (IEEC), said: “PAU Research offers an innovative approach to space mapping, enabled by the design and development of collecting data in a way that has never been done before.” “And it was a great honor to work with such a talented and reliable group to develop a new tool and custom surveys to analyze it.”

The publication of the catalog is described in detail in two articles. One about PAUS data calibration was posted at: Monthly Notices of the Royal Astronomical Society. Another on measuring distances was accepted for publication MNRAS and is available on the preprint server arXiv.

David Navarro-Girones, Ph.D. ICE-CSIC student and first author of the paper arXivHe said: “The biggest advantage of PAUS is that…[дозволяє] Make high-precision distance measurements. “This level of precision is crucial for studying the structure of the universe, which requires data from large numbers of galaxies.”

Nine years after its first light in 2015, PAUS can measure distances to many distant galaxies with a relative accuracy of 0.3%. The team is currently using these data to improve the calibration of existing cosmological studies.

For example, PAUS data is used to improve weak lensing analysis and modeling for dark energy missions such as the European Space Agency’s Euclid mission and the Rubin Legacy Space Probe, whose Large Optical Camera is being built by an international team led by UCL researchers. observatory and time (LSST).