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📃Scientific paper: Millimeter-wave CO and SiO Observations toward the Broad-velocity-width Molecular Feature CO 16.134-0.553: a Smith cloud scenario? Abstract: We report the results of the CO $\textit J$=1-0 and SiO $\textit J$=2-1 mapping observations towards the broad-velocity-width molecular feature CO 16.134-0.553 with the Nobeyama Radio Observatory 45 m telescope. The high quality CO map shows that the 5-pc size broad-velocity-width feature bridges two separate velocity components at $\textit V\_\{\rm\{LSR\}\}$$\quad$$\simeq$ 40 km s$^\{-1\}$ and 65 km s$^\{-1\}$ in the position-velocity space. The kinetic power of CO 16.134-0.553 amounts to $7.8\times10^2$ $\textit L$$\_\odot$ whereas no apparent driving sources were identified. Prominent SiO emission was detected from the broad-velocity-width feature and its root in the $\textit V\_\{\rm\{LSR\}\}$$\quad$$\simeq$ 40 km s$^\{-1\}$ component. In the CO Galactic plane survey data, CO 16.134-0.553 appears to correspond to the Galactic eastern rim of a 15-pc diameter expanding CO shell. An $1\deg$-diameter H I emission void and $4\deg$-long vertical H I filament were also found above and below the CO shell, respectively. We propose that the high-velocity plunge of a dark matter subhalo with a clump of baryonic matter was responsible for the formation of the H I void, CO 16.134-0.553/CO shell, and the H I filament. ;Comment: 7 pages, 6 figures, 2 table, accepted for publication in ApJ Continued on ES/IODE ➡️ https://etcse.fr/Bmuf ------- If you find this interesting, feel free to follow, comment and share. We need your help to enhance our visibility, so that our platform continues to serve you.

📃Scientific paper: The FAST all sky HI survey (FASHI): The first release of catalog Abstract: The FAST All Sky HI survey (FASHI) was designed to cover the entire sky observable by the Five-hundred-meter Aperture Spherical radio Telescope (FAST), spanning approximately 22000 square degrees of declination between -14 deg and +66 deg, and in the frequency range of 1050-1450 MHz, with the expectation of eventually detecting more than 100000 HI sources. Between August 2020 and June 2023, FASHI had covered more than 7600 square degrees, which is approximately 35% of the total sky observable by FAST. It has a median detection sensitivity of around 0.76 mJy/beam and a spectral line velocity resolution of ~6.4 km/s at a frequency of ~1.4 GHz. As of now, a total of 41741 extragalactic HI sources have been detected in the frequency range 1305.5-1419.5 MHz, corresponding to a redshift limit of z<0.09. By cross-matching FASHI sources with the Siena Galaxy Atlas (SGA) and the Sloan Digital Sky Survey (SDSS) catalogs, we found that 16972 (40.7%) sources have spectroscopic redshifts and 10975 (26.3%) sources have only photometric redshifts. Most of the remaining 13794 (33.0%) HI sources are located in the direction of the Galactic plane, making their optical counterparts difficult to identify due to high extinction or high contamination of Galactic stellar sources. Based on current survey results, the FASHI survey is an unprecedented blind extragalactic HI survey. It has higher spectral and spatial resolution and broader coverage than the Arecibo Legacy Fast ALFA Survey (ALF... Continued on ES/IODE ➡️ https://etcse.fr/iGKHn ------- If you find this interesting, feel free to follow, comment and share. We need your help to enhance our visibility, so that our platform continues to serve you.

In a new study using data from the James Webb Space Telescope (JWST), Prof. Dasyra of the National and Kapodistrian University of Athens, Greece, and her team provided insights into how supermassive black holes affect galaxy evolution by driving interstellar gas out of galactic disks. A supermassive black hole at the center of this fascinating nearby galaxy ejects jets, which are collimated beams of particles traveling at high velocities, near the speed of light. By employing JWST's Mid-Infrared Instrument (MIRI), the researchers were able to capture high-resolution images and spectra from a region surrounding the center of IC5063 that spans a distance equivalent to ~1/3 of the distance between our sun and the center of our own galaxy. One of the most striking outcomes of this research is the identification of more than 10 distinct regions with winds, nearly doubling the known areas where gas is being expelled from the galaxy's nucleus following the impact of black-hole jets. Some of these winds are moving at velocities that exceed what would be necessary to escape the galaxy's gravitational pull—a result proving that black hole jets can delay star formation by depleting a galaxy from the gas that would be needed to collapse and form stars. These outflows also exhibit diverse structures and characteristics, such as differences in the temperature of the gas they entrain. This study also sheds light on the past jet activity of IC5063. The researchers discovered gas in bow shocks, i.e., bow-shaped structures that form when jet particles plow through the interstellar medium at supersonic speeds, leading to the compression, heating, and acceleration of their surrounding gas. These shocks are analogous to the sonic booms produced by aircraft that exceed the sound speed in the Earth's atmosphere. The extent of the detected bow shocks is vast, spanning ~300 pc or 6 billion times the distance between the JWST and Earth. Surprisingly, their location is well beyond the region of the nucleus of IC5063 where the black hole jets are detected by their radio emissions. This finding indicates that jets may have interacted with the surrounding gas in the past and then faded away, in a recurrent activity of particle ejection from the vicinity of the supermassive black hole that continues to shape the galaxy today. #MIRI #JWST #IC5063 A view of IC5063. In the nucleus, newly detected winds in the JWST MIRI data are shown in orange (for the molecular gas) and blue (for the ionized gas; from Dasyra et al, 2024, ApJ, in press). Background: composite optical image, from data of two Hubble Space Telescope (HST) snapshot proposals (15446 and 15444) and the Legacy Survey, DR9 release. For the Legacy Survey data, DECam g is shown in blue, DECam r is in green and DECam z is in red. For the HST data, ACS/WFC F606W is in blue and ACS/WFC F814W is in red. (JWST data, NASA, ESA & CSA)

A super-Eddington-accreting black hole ~1.5 Gyr after the Big Bang observed with JWST. Abstract :"Recent James Webb Space Telescope (JWST) observations have revealed a surprisingly abundant population of faint, dusty active galactic nuclei at z ≈ 4–7. Together with the presence of supermassive black holes at z > 6, this raises questions about the formation and growth histories of early black holes. Current theories for the formation of seed black holes from the death of the first stars (that is, light seeds) and/or the direct collapse of primordial gas clouds (that is, heavy seeds) still lack observational confirmation. Here we present LID-568, a low-mass (7.2 × 106 M⊙) black hole hosting powerful outflows that is observed in an extreme phase of rapid growth at redshift z ≈ 4. This object is similar to other JWST-discovered faint active galactic nuclei populations, but is bright in X-ray emission and accreting at more than 4,000% of the limit at which radiation pressure exceeds the force of gravitational attraction of the black hole (that is, super-Eddington accretion). Analysis of JWST Near-Infrared Spectrograph integral field unit data reveals spatially extended Hα emission with velocities of ~−600–−500 km s−1 relative to the central black hole, indicative of robust nuclear-driven outflows. LID-568 represents an elusive low-mass black hole experiencing super-Eddington accretion as invoked by models of early black hole formation. This discovery showcases a previously undiscovered key parameter space and offers crucial insights into rapid black hole growth mechanisms in the early universe." https://lnkd.in/gz-rnq4b

maxon Motors for Telescopes The HETDEX project (Hobby-Eberly Telescope Dark Energy Experiment) is the first major attempt to find and examine “dark energy” in the universe. Through this project, we are able to record three-dimensional positions of one million galaxies using special spectrographs. In the summer of 2012, the Hobby-Eberly Telescope began scanning the universe with the help of maxon motors for telescopes. Hobby-Eberly Telescope (HET) The Hoby-Eberly Telescope is located at the McDonald Observatory in West Texas and contains a spherical mirror with 91 identical hexagonal segments, each one meter in size. These mirror segments for a mirror with a diameter of 11 meters, making it the largest in the world. The HET in and of itself is the fourth largest optical telescope in the world, but due to its innovative design, it was cost-effective to make. Costing around $13.5 million, the HET cost about ¼ the cost of a comparably large telescope. This spectroscopic telescope is mounted on a Prime Focus Instrument Package (PFIP) equipped with two spectrographs. The mirror always points at a position 55 degrees above the horizon, but it can be swiveled horizontally full circle, allowing it to observe 70% of the skies. In future projects, upgrades to the wide field components will increase the angle of view to 22 arc minutes and usable aperture to 10 meters, making it possible to gather the highest possible light quantity via glass fiber coupling. These upgrades will revolutionize spectroscopic observation. Scientists want to use this upgraded version of the HET to obtain a better understanding of “dark energy.” Current hypotheses stipulate that almost ¾ of all matter and energy in the universe consists of “dark energy.” Dark energy is considered to be a mysterious force that causes the universe to drift apart at increasing speeds at it ages. Click below to read the complete article: https://lnkd.in/dCP4pGB9 #maxonmotor #BLDCmotor #brushlessdirectcurrentmotor

Recent observations using the MeerKAT telescope in South Africa have led to the discovery of 26 new Galactic radio transients, primarily identified as rotating radio transients (RRATs). These findings, part of the MeerTRAP project, underscore the significance of commensal observations in advancing our understanding of radio-emitting neutron stars. The newly identified transients exhibit dispersion measures between 8.46 and 346.5 pc/cm³, with spin periods ranging from 1.06 to 17.49 seconds. Notably, two transients, MTP0021/PSR J0219−06 and MTP0023/PSR J1319−4536, display complex pulse structures, warranting further study.

📃Scientific paper: A Millisecond Pulsar Binary Embedded in a Galactic Center Radio Filament Abstract: The Galactic Center is host to a population of extraordinary radio filaments, thin linear structures that trace out magnetic field lines running perpendicular to the Galactic plane. Using Murriyang, the 64 m Parkes radio telescope, we conducted a search for pulsars centered on the position of a compact source in the filament G359.0$-$0.2. We discovered a millisecond pulsar \(MSP\), PSR J1744$-$2946, with a period $P = 8.4$ ms, that is bound in a 4.8 hr circular orbit around a $M\_\{\rm c\} \> 0.05\,M\_\{\odot\}$ companion. The pulsar dispersion measure of $673.7 \pm 0.1$ pc cm$^\{-3\}$ and Faraday rotation measure of $3011 \pm 3$ rad m$^\{-2\}$ are the largest of any known MSP. Its radio pulses are moderately scattered due to multi-path propagation through the interstellar medium, with a scattering timescale of $0.87 \pm 0.08$ ms at 2.6 GHz. Using MeerKAT, we localized the pulsar to a point source embedded in a low-luminosity radio filament, the "Sunfish", that is unrelated to G359.0$-$0.2. Our discovery of the first MSP within 1$^\{\circ\}$ of the Galactic Center hints at a large population of these objects detectable via high frequency surveys. The association with a filament points to pulsars as the energy source responsible for illuminating the Galactic Center radio filaments. ;Comment: 6 pages, 4 figures, 1 table. Accepted for publication in ApJ Letters Continued on ES/IODE ➡️ https://etcse.fr/vVZ2X ------- If you find this interesting, feel free to follow, comment and share. We need your help to enhance our visibility, so that our platform continues to serve you.

#astronomy #cosmology An article published in the journal "Nature" reports the identification of the origin of the fast radio burst cataloged as FRB 20221022A linking it to a #magnetar-class neutron star, probably emerging from its magnetosphere. A team of researchers coordinated by MIT used observations conducted with the CHIME radio telescope to identify the origin of this already-known fast radio burst by exploiting the phenomenon of scintillation, comparable to how stars twinkle in the sky. This is further evidence of the link between magnetars and fast radio bursts, the very powerful emissions that can be one-time or repeated events. https://lnkd.in/d6vQfh6Y

While Italy (Einstein Telescope IT) and the Netherlands (Einstein Telescope) prepare their bids to host the next gravitational wave observatory, the collaboration is considering an alternative design that would use both sites. The #EinsteinTelescope was originally proposed as a triangle with 10-kilometer sides located nearly 300 metres underground to reduce noise sources. But now the international collaboration that manages the project has started to consider an alternative design, based on two L-shaped interferometers with 15-kilometre arms, one in Sardinia near the Sos Enattos dismissed mine and the other near Maastricht, about 1,000 kilometres apart. If this new proposal to build two detectors instead of one gains momentum, the competition between Italy and the Netherlands could end in a draw. I spoke to scientists in the Einstein Telescope collaboration and in the bid teams to understand which factors will shape the final decision. The two L-shaped detectors seem to perform better on nearly on scientific questions than the triangle, but costs and feasibility could end up being the most influential aspects. You can find the full article in Nature Italy (Nature Portfolio) Thanks to my sources that shared with me their thoughts, INFN, GSSI - Gran Sasso Science Institute, IFAE, Nikhef (Nationaal instituut voor subatomaire fysica) Vrije Universiteit Amsterdam (VU Amsterdam), Universiteit Utrecht https://lnkd.in/d8pE3m5D

https://buff.ly/49n9ldn You can knock a good telescope out, but you can't keep it down. Using data from the now-destroyed Arecibo radio telescope, scientists from the Search for Extraterrestrial Intelligence (SETI) Institute have unlocked the secrets of signals from "cosmic lighthouses" powered by dead stars. In particular, the team led by Sofia Sheikh from the SETI Institute was interested in how the signals from pulsars distort as they travel through space. Pulsars are dense stellar remnants called neutron stars that blast out beams of radiation that sweep across the cosmos as they spin. To study how these stars' signals are distorted in space, the team turned to archival data from Arecibo, a 1,000-foot (305-meter) wide suspended radio dish that collapsed on Dec. 1, 2020, after the cables supporting it snapped, punching holes in the dish. The researchers investigated 23 pulsars, including 6 which had not been studied before. This data revealed patterns in pulsar signals showing how they were impacted by the passage through gas and dust that exists between stars, the so-called "interstellar medium."