First Sagittarius A* Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole in the Center of the Milky Way

التفاصيل البيبلوغرافية
العنوان: First Sagittarius A* Event Horizon Telescope Results. I. The Shadow of the Supermassive Black Hole in the Center of the Milky Way
المؤلفون: The Event Horizon Telescope Collaboration
المصدر: The Astrophysical Journal Letters, Volume 930, Number 2, id L12, 21pp., 2022 May 12
سنة النشر: 2023
المجموعة: Astrophysics
مصطلحات موضوعية: Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Astrophysics of Galaxies
الوصف: We present the first Event Horizon Telescope (EHT) observations of Sagittarius A* (Sgr A$^*$), the Galactic center source associated with a supermassive black hole. These observations were conducted in 2017 using a global interferometric array of eight telescopes operating at a wavelength of $\lambda=1.3\,{\rm mm}$. The EHT data resolve a compact emission region with intrahour variability. A variety of imaging and modeling analyses all support an image that is dominated by a bright, thick ring with a diameter of $51.8 \pm 2.3$\,\uas (68\% credible interval). The ring has modest azimuthal brightness asymmetry and a comparatively dim interior. Using a large suite of numerical simulations, we demonstrate that the EHT images of Sgr A$^*$ are consistent with the expected appearance of a Kerr black hole with mass ${\sim}4 \times 10^6\,{\rm M}_\odot$, which is inferred to exist at this location based on previous infrared observations of individual stellar orbits as well as maser proper motion studies. Our model comparisons disfavor scenarios where the black hole is viewed at high inclination ($i > 50^\circ$), as well as non-spinning black holes and those with retrograde accretion disks. Our results provide direct evidence for the presence of a supermassive black hole at the center of the Milky Way galaxy, and for the first time we connect the predictions from dynamical measurements of stellar orbits on scales of $10^3-10^5$ gravitational radii to event horizon-scale images and variability. Furthermore, a comparison with the EHT results for the supermassive black hole M87$^*$ shows consistency with the predictions of general relativity spanning over three orders of magnitude in central mass.
Comment: 24 pages, 6 figures, published in The Astrophysical Journal Letters on May 12, 2022. See the published paper for the full authors list
نوع الوثيقة: Working Paper
DOI: 10.3847/2041-8213/ac6674
URL الوصول: http://arxiv.org/abs/2311.08680
رقم الأكسشن: edsarx.2311.08680
قاعدة البيانات: arXiv
الوصف
DOI:10.3847/2041-8213/ac6674