An artist’s impression reveals the previously unknown complexity of the young galaxy A1689-zD1.
Scientists used the Atacama Large Millimeter/Submillimeter Array (ALMA) to observe a significant amount of cold neutral gas in the outer regions of the young galaxy A1689-zD1, as well as streams of hot gas from the center of the galaxy.
These results may shed light on a critical phase of galactic evolution for early galaxies, when young galaxies begin to transform to look more and more like their new, more structured cousins.
The observations were presented at a press conference at the 240th meeting of the American Astronomical Society in Pasadena, California, and will be published in the next issue of the journal Astrophysical Journal.
A1689-zD1 is a young active star-forming galaxy. Slightly less bright and less massive than the Milky Way, it is located about 13 billion light-years from Earth in the direction of the constellation Virgo.
Was opened hidden behind the galaxy cluster Abell 1689 in 2007 and confirmed in 2015 due to gravitational lensing, which increased the brightness of the young galaxy by more than 9 times.
Since then, scientists have continued to study the galaxy as a possible analogue evolution of other “normal” galaxies.
This label is ordinary is an important distinction that has helped researchers divide the behavior and characteristics of A1689-zD1 into two groups: typical and unusual, with the unusual characteristics mimicking those of newer and more massive galaxies.
“A1689-zD1 is in the early universe. – just 700 million years after the Big Bang. This is the era when galaxies were just beginning to form,” he said. Hollis Akinsundergraduate student in astronomy at Grinnell College and lead author of the study.
“What we see in these observations is evidence of processes that may contribute to the evolution of what we call normal galaxies, unlike massive galaxies. Most importantly, these processes are processes that we previously thought did not apply to these ordinary galaxies.”
One of these unusual processes is the production and distribution in the galaxy fuel for star formationpotentially in large quantities.
The team used the highly sensitive Band 6 ALMA receptor to observe a halo of carbon gas that extends far beyond the center of the young galaxy.
This may be evidence of ongoing star formation in the same region, or the result of structural disturbances such as mergers or outflows during earlier stages of galaxy formation.
This is unusual for early galaxies, Akins says. “The carbon gas that we have observed in this galaxy is usually found in the same regions as neutral hydrogen gas, where new stars also tend to form. If this is true for A1689-zD1, the galaxy is likely much larger than previously thought.”
“It is also possible that this halo is remnant of galactic activity earlier, such as mergers that impacted the galaxy with complex gravitational forces, which led to the release of large amounts of neutral gas over these large distances, ”adds the astronomer.
“In both cases, the early evolution of this galaxy was probably active, dynamic and we learn that this can be a common themealthough not previously observed during the formation of the first galaxies,” concludes Akins.
This discovery may not just be unusual, it could have significant implications for the study of galactic evolution, especially as radio observations unravel invisible details at optical wavelengths.
Seiji FujimotoA researcher at the Niels Bohr Institute’s Space Dawn Center, who co-authored the study, said: “The carbon dioxide emissions of A1689-zD1 are much more extensive than those observed with the Hubble Space Telescope, which could mean that the first galaxies are not as small as they seem. “.
“If in fact the first galaxies are larger than we previously thought, this great influence on the theory the formation and evolution of galaxies in the early universe,” adds Fujimoto.
Led by Akins, the team also observed bursts of hot ionized gas, often triggered by violent galactic activity such as supernovae, that were being pushed outwards from the center of the galaxy. Given its potentially explosive nature, flows may have something to do with the carbon halo.
“Flows arise as result of violencesuch as supernova explosions, which eject nearby gaseous material from the galaxy — or black holes at the centers of galaxies — which have a strong magnetic effect that can eject material in powerful jets,” Akins said.
“Because of this, there is a strong possibility that warm flows are somehow related to the presence of a cold carbon halo. And it’s rfurther emphasizes the importance multi-phase, or hot to cold, nature of the gas flow,” he added.
Darah Watson, Associate professor at the Niels Bohr Institute’s Cosmic Dawn Center and co-author of the new study confirmed that A1689-zD1 is a high-redshift galaxy in 2015, the most distant known dusty galaxy.
“We have seen this type of large burst of gaseous halos from galaxies that formed later in the universe, but seeing it in such an early galaxy means that this behavior universal even in the humblest galaxies from which most of the stars in the early universe formed,” Watson said.
“Understanding how these processes occurred in such a young galaxy is critical to understand how star formation occurs in the early universe,” the astronomer added.
Kirsten Knudsenprofessor of astrophysics in the Department of Space, Earth and Environment at Chalmers University of Technology and co-author of the study, in 2017 found evidence for the existence of the dust continuum A1689-zD1. Knudsen emphasized the random role of extreme gravitational lensing in making every possible discovery in the investigation.
“Given that A1689-zD1 is more than nine times magnified, we can see important details that are otherwise difficult to see with conventional observations of galaxies so far away. In the end, we see here that the first galaxies Universes are very complex, and this galaxy will set new tasks and research results for some time to come,” the researcher said.
Doctor. Joe Pesce, ALMA Program Manager at the National Science Foundation, added: “This exciting ALMA study adds to a growing set of results indicating that things in the early universe are not exactly what we expected, but are nonetheless really interesting and exciting. !”
Spectroscopic and infrared observations of A1689-zD1 are scheduled for January 2023 using the NIRSpec IFU (Integral Field Unit) and NIRCam instruments on the James Webb Space Telescope.
The new observations will complement previous Hubble and ALMA data, providing a deeper and more complete multiwavelength look at the young galaxy.
Xiaomi POCO F4 GT is one of the cheapest smartphones on the market with a Snapdragon 8 Gen 1 processor. This is the Chinese company’s best offering for the gaming segment, but its performance leaves much to be desired.
This unfortunate scenario was once again confirmed in the latest POCO F4 GT test conducted by the Golden Reviewer Youtube channel. Compared to its peers, this Chinese smartphone could not keep up with the competition.
Xiaomi POCO F4 GT doesn’t want fps in Apex Legends Mobile
The newly released game Apex Legends Mobile was chosen to test the gaming performance of POCO F4 GT. Unfortunately for fans of the brand, the results put him at the end of the table.
On average, Xiaomi POCO F4 GT is presented only 47.5 fps during the gaming session, which you can see in the video above. Clearly poor performance for a smartphone with a strong focus on this market niche.
The performance limitations of the POCO F4 GT start to be noticed already in the third minute of the test. Then we started seeing performance drops for no apparent reason.
From the tenth minute of the test until its end, we see a constant performance in the region of 40 frames per second. Although the POCO F4 GT reached a peak speed of 60fps, it was unable to maintain those numbers throughout the test.
In first place in the table built by the Golden Reviewer channel, we have the Redmi K50 Pro with an average of 59.6 fps. This is an exclusive smartphone for the Chinese market, equipped with a Dimensity 9000 processor.
For European consumers, we have the iPhone 13 Pro Max showing the best performance in this test with an average of 59.1 fps. For Android lovers, the Samsung Galaxy S22 Ultra came out on top with an average of 57.4 fps.
Instagram is testing new ways to verify the age of its users, including an AI face identification tool to make sure people are 18 or older.
There are no tools yet to prevent children from accessing the Meta platform.
The use of artificial intelligence to identify faces, especially in teenagers, has raised some concerns given the Meta’s complicated history. when it comes to protecting user privacy.
Meta stressed that the technology used to check the age of people can’t find out your identity – only your age. After completion of Meta validation in partnership with startup Yoti delete face video.
The owner of Facebook and Instagram said that from today, if anyone tries to change their date of birth on the platform for posting videos and photos of people under or over 18, you will need to verify your age using one of these methods.
Meta continues to face questions about the negative impact its products, especially Instagram, have on some teens.
Technically, children must be at least 13 years old to join Instagram, similar to other social networks. But some solve this problem by lying about their age or by having their parents do it.
To use the face scan feature, the user has to send a “selfie” videosent to Yoti, a London-based startup that uses people’s facial features to estimate their age.
Yoti is one of several biometric companies that are capitalizing on the UK and European push for more reliable age verification technology. to prevent children from accessing pornography, dating apps, and other adult content.
“While Instagram is likely making good on its promise to remove images of candidates’ faces and not attempting to use them for individual facial recognition, the normalization of facial scans raises other social concerns,” a professor at Cambridge University Essex School of Law warned. (United Kingdom) Darag Murray.
In 2021, Meta announced that it was shutting down Facebook’s facial recognition system and removing the fingerprints of more than a billion people after years of scrutiny by courts and regulators.
José Antonio Correia, Research Fellow at the Faculty of Engineering and INEGI, has become the new Chief Co-Editor of the well-known “Alexandria Engineering Journal”.
José Antonio Correia has been in the top 2% most cited scientists in the world since 2019 according to the Stanford University rankings.Photo: DR
Jose Antonio Correiaresearcher Institute for Research and Development in Structural and Construction (CONSTRUCT) as well as University of Porto Faculty of Engineering (FEUP) It’s from Institute of Science and Innovation in Mechanical Engineering and Industrial Construction (INEGI)recently appointed co-editor of the civil engineering department Alexandria Engineering Journal(Elsevier), the leading journal in engineering and applied sciences.
“I am honored to be part of a journal in which distinguished world-class professors and researchers participate as members of the editorial board, and at the same time to be recognized for my contributions to the fields of materials and engineering structures. I also express my gratitude to the institutions in which I work for the support and availability of the necessary funds for the development of my research activities and cooperation with the industry,” says the researcher.
Bye co-editorf, José Antonio Correia will have primary responsibility for managing submissions from the civil engineering academic community, putting them into the review and final decision process.
Scientific research and recognition
Since 2019, José Antonio Correia has been ranked among the top 2% most cited scientists in the world by Stanford University, having recently won the award. 2021 IGF Manson-Coffin Medal. He was also considered one of the most influential academics in the world during the period 2015-2021 in several scientific areas of fatigue such as SN curves, fatigue models applied to materials and structural parts, accumulated damage, metal bridges and structures. connections.
Most recently, the EFUP researcher was appointed co-chair of the European Structural Integrity Society (ESIS) TC3 Technical Committee – Fatigue of Engineering Materials and Structures, a body on which he already served as Chairman of the TC12 Technical Committee – Safety and Risk Analysis of Large Structures and Structural Parts. In addition, he acted as an evaluator of European project proposals.
In addition, he is the founder and current co-editor of Structural Integrity – Series (Springer), together with Abilio De Jesus, Professor of the Department of Mechanical Engineering of the FEUP, Editor-in-Chief of the Journal Department MDPI simulationmagazine editor Open study materials (F1000-Taylor & Francis), e Make editor-in-chief International Journal of Structural Integrity (Emerald).
With a research activity “divided” between CONSTRUCT and INEGI, José Antonio Correia also teaches at the Faculty of Science and Technology of the University of Coimbra, at the University of Tras os Montes e Alto Douro (UTAD), as well as at the Department of Constructions of the Faculty of Civil Engineering and Geosciences Delft University of Technology (Netherlands).
At FEUP, he is also co-coordinator, along with Professor Rui Calzada, of the Hyperloop-Verne project recently approved by the MIT Portugal program. The researcher has been co-coordinator of several research and university projects in the field of structural integrity, fatigue and failure of materials, engineering details and structures.
He also holds several honorary positions at the invitation of university institutions around the world such as Xi’an Jiaotong University (China), where he is an Associate Professor, or NIT Silchar (India) and Universidade Estadual Paulista (UNESP, Brazil), where he is an Invited professor.