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#quasar

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Daniel Fischer

WFI2033--4723, the First Quadruply-Imaged #Quasar Modeled with JWST Imaging: arxiv.org/abs/2503.00099 -> picture: bsky.app/profile/jwstfeed.bsky pic

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arXiv.orgTDCOSMO: XX. WFI2033--4723, the First Quadruply-Imaged Quasar Modeled with JWST ImagingGravitational time delays offer unique, independent measurements of the Hubble constant, $H_0$. Precise measurements of $H_0$ stand as one of the most pressing challenges in modern cosmology, and to do so with time delays requires precise lens models. While much work has focused on streamlining the modeling process to keep pace with the erumpent discovery of strongly-lensed systems, a critical step toward reducing uncertainty in $H_0$ comes from increasing the precision of individual lens models themselves. In this work, we demonstrate that the unprecedented imaging capabilities of JWST make this goal attainable. We present the first lens model for time-delay cosmography derived from JWST data, applied to the quadruply-imaged quasar WFI2033--4723. While the primary source of systematic uncertainty in time-delay cosmography is currently the mass-sheet degeneracy (MSD), the sensitivity of models to this MSD varies on how the point spread function (PSF) errors are mitigated. As the PSF is also the primary source of uncertainty in lens modeling, we focus on a comparison of different PSF modeling methods. Within the context of power-law models, we recover results in agreement with previous Hubble Space Telescope (HST)-based models, but with better precision of key lensing parameters through implementation of new PSF modeling techniques. Despite the record-holding precision of this system's HST modeling, we achieve an additional 22% increase in precision of the Fermat potential difference, directly reducing uncertainties of cosmological inference. These results would produce a 3% ($1σ$ of the modeling error) shift of $H_0$ towards a higher value for this lens, keeping all else constant. This work substantiates the groundbreaking potential of JWST for time-delay cosmography and lays the groundwork for modeling systems previously too faint to provide meaningful constraints on $H_0$.
Public
Daniel Fischer

High-definition imaging of a filamentary connection between a close #quasar pair at z = 3: nature.com/articles/s41550-024 -> Wicked High-Definition Image of the Cosmic Web Shows the Universe’s Dark Matter Scaffolding: gizmodo.com/wicked-high-defini - new data reveals a 3-million-light-year filament connecting two galaxies, each of which hosts a supermassive black hole.

NatureHigh-definition imaging of a filamentary connection between a close quasar pair at z = 3 - Nature AstronomyDeep optical imaging of a close quasar pair reveals a filamentary connection between them, providing insight into the transition between intergalactic and circumstellar media and a test of the cold-dark-matter cosmological theory.
Public
RTN

#MPIK:
"
So klein und doch so stark - Die verborgene Kraft der kleinsten Mikroquasare

Forschenden gelang erstmal der Nachweis, dass selbst Mikroquasare mit geringen Sternmassen effiziente Teilchenbeschleuniger sind, was erhebliche Auswirkungen auf die Interpretation des Gesamtvorkommens von Gammastrahlen im Universum hat.
"
mpi-hd.mpg.de/mpi/de/nachricht

28.1.2025

#Astronomie #Astrophysik #Beschleuniger #Fermi #Gammastrahlung #GRS1915+105 #Mikroquasar #Quasar #SS433 #Strahlung #Universum

www.mpi-hd.mpg.deSo klein und doch so stark - Die verborgene Kraft der kleinsten MikroquasareForschenden gelang erstmal der Nachweis, dass selbst Mikroquasare mit geringen Sternmassen effiziente Teilchenbeschleuniger sind, was erhebliche Auswirkungen auf die Interpretation des Gesamtvorkommens von Gammastrahlen im Universum hat.
Public
Daniel Fischer

High-definition imaging of a filamentary connection between a close #quasar pair at z=3: arxiv.org/abs/2406.17035 -> Researchers capture direct high-definition image of the “Cosmic Web”: mpa-garching.mpg.de/1109034/ne

arXiv logo
arXiv.orgHigh-definition imaging of a filamentary connection between a close quasar pair at z=3Filaments connecting halos are a long-standing prediction of cold dark matter theories. We present a detection of the cosmic web emission connecting two quasar-host galaxies at redshift z ~3.22 in the MUSE Ultra Deep Field (MUDF). The very deep observations unlock a high-definition view of the filament morphology, a measure of the transition radius between the intergalactic and circumgalactic medium, and the characterization of the surface brightness profiles along the filament and in the transverse direction. Through systematic comparisons with simulations, we validate the filaments' typical density predicted in the current cold dark-matter model. Our analysis of the MUDF field, an excellent laboratory for quantitatively studying filaments in emission, opens a new avenue to constrain the physical properties of the cosmic web and to trace the distribution of dark matter on large scales.
Public
Massimo Luciani

#astronomy #SMBH #quasar Two articles - one published in the journal "Nature Astronomy" and one in "The Astrophysical Journal Letters" - report different aspects of a study of the #blazar cataloged as VLASS J041009.05−013919.88, or simply J0410−0139, the most distant found so far. Two teams of researchers used several space and ground-based telescopes and some radio telescopes to obtain detections in various electromagnetic bands.

english.tachyonbeam.com/2024/1

english.tachyonbeam.comThe most distant blazar discovered yet suggests a quick formation of supermassive black holesTwo articles - one published in the journal 'Nature Astronomy' and one in 'The Astrophysical Journal Letters' - report different aspects of a study of the...
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Hans 🙋‍♂️

"Eenzame quasars in het vroege heelal stellen astronomen voor een raadsel"

--> "Een aantal jaar geleden ontdekten astronomen dat deze superzware, schransende zwarte gaten al in het vroege heelal te vinden waren."

--> "Astronomen hebben [...] een aantal quasars ontdekt die vrijwel alleen door het heelal lijken te dwalen. Dat druist tegen de theorie in."

(Via #newscientist_NL ) #nieuwsbrief #quasar
newscientist.nl/nieuws/eenzame

New ScientistEenzame quasars in het vroege heelal stellen astronomen voor een raadselQuasars, heldere sterrenstelsels met gigantische zwarte gaten, dwalen alleen door het vroege heelal. Dat stelt astronomen voor een raadsel.
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