Mastodawn

The Galactic Defrag: Clearing at $27^\circ$ Sagittarius 🌀 #GalacticCenter #Awakening

On the Deepest Search for #GalacticCenter Pulsars and an Examination of an Intriguing #MillisecondPulsar Candidate: https://iopscience.iop.org/article/10.3847/1538-4357/ae336c -> Discovery of a Possible #Pulsar in the Milky Way’s Center: https://news.columbia.edu/news/researchers-announce-discovery-possible-pulsar-milky-ways-center - confirming a pulsar star would enable unprecedented tests of General Relativity. Such a discovery would revolutionize physics.

On the Deepest Search for Galactic Center Pulsars and an Examination of an Intriguing Millisecond Pulsar Candidate

On the Deepest Search for Galactic Center Pulsars and an Examination of an Intriguing Millisecond Pulsar Candidate, Perez, Karen I., Gajjar, Vishal, Bogdanov, Slavko, Halpern, Jules P., Demorest, Paul B., Croft, Steve, Lebofsky, Matt, MacMahon, David H. E., Siemion, Andrew P. V.

adsdaily Feb 1

📄 Detection of Millimeter-wavelength Flares from Two Accreting White Dw…

Quicklook:
Wan, Y. et al. (2026) · The Astrophysical Journal
Reads: 281 · Citations: 0
DOI: 10.3847/1538-4357/ae2de8

🔗 https://ui.adsabs.harvard.edu/abs/2026ApJ...997..133W/abstract

#Astronomy #Astrophysics #MillimeterAstronomy #Surveys #GalacticCenter

Detection of Millimeter-wavelength Flares from Two Accreting White Dwarf Systems in the SPT-3G Galactic Plane Survey

Blind discoveries of millimeter-wave transient events in nontargeted surveys, as opposed to follow-up or pointed observations, have only become possible in the past decade using cosmic microwave background surveys. Here we present the first results from the SPT-3G Galactic Plane Survey—the first dedicated high-sensitivity, wide-field, time-domain, millimeter-wave survey of the Galactic Plane, conducted with the South Pole Telescope (SPT) using the SPT-3G camera. The survey field covers approximately 100 deg2 near the Galactic center. In 2023 and 2024, this survey consisted of roughly 1500 individual 20 minute observations in three bands centered at 95, 150, and 220 GHz, with plans for more observations in the coming years. We report the detection of two transient events exceeding a 5σ threshold in both the 95 and 150 GHz bands in the first 2 yr of SPT-3G Galactic Plane Survey data. Both events are unpolarized and exhibit durations of approximately 1 day, with peak flux densities at 150 GHz of at least 50 mJy. The peak isotropic luminosities at 150 GHz are on the order of 1031 erg s−1. Both events are associated with previously identified accreting white dwarfs. Magnetic reconnection in the accretion disk is a likely explanation for the observed millimeter flares. In the future, we plan to expand the transient search in the Galactic Plane by lowering the detection threshold, enabling single-band detections, analyzing lightcurves on a range of timescales, and including additional data from future observations.

ADS

German Virtual Observatory Jan 17

New in the #VirtualObservatory: “ISM phases and abundances in the central parsec” by Vermot P. et al.
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/704/A295
#InfraredAstronomy #Spectroscopy #GalacticCenter

VizieR J/A+A/704/A295

VizieR catalogues

AlcorNews Dec 21

Des indices de matière noire émergent au centre de notre galaxie, relançant le débat sur l’invisible qui façonne l’Univers.
https://www.sciencesetavenir.fr/espace/astrophysique/des-indices-de-matiere-noire-au-centre-galactique_189584
#Space #Science #Innovation #Astrophysics #GalacticCenter #DarkMatter #CosmicMystery

Daniel Fischer Oct 18

Fermi-LAT #GalacticCenter Excess morphology of dark matter in simulations of the Milky Way galaxy: https://arxiv.org/abs/2508.06314 -> New simulations tilt the scales for competing theories about excess gamma ray light at the center of the galaxy / Milky Way shows gamma ray excess due to dark matter annihilation: https://hub.jhu.edu/2025/10/16/mysterious-glow-in-milky-way-dark-matter/ / https://www.aip.de/en/news/milkyway-gammaray-darkmatter-annihilation/

Fermi-LAT Galactic Center Excess morphology of dark matter in simulations of the Milky Way galaxy

The strongest experimental evidence for dark matter is the Galactic Center gamma-ray excess observed by the Fermi telescope and even predicted prior to discovery as a potential dark matter signature via WIMP dark matter self-annihilations. However, an equally compelling explanation of the excess gamma-ray flux appeals to a population of old millisecond pulsars that also accounts for the observed boxy morphology inferred from the bulge old star population. We employ a set of Milky Way-like galaxies found in the Hestia constrained simulations of the local universe to explore the rich morphology of the central dark matter distribution, motivated by the GAIA discovery of a vigorous early merging history of the Milky Way galaxy. We predict a significantly non-spherical gamma-ray morphology from the WIMP interpretation. Future experiments, such as the Cherenkov Telescope Array, that extend to higher energies, should distinguish between the competing interpretations.

arXiv.org

German Virtual Observatory Oct 4

New in the #VirtualObservatory: “GaiaUnlimited. Milky Way red clump catalogue” by Khanna S. et al.
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/701/A270
#StellarPopulations #GalacticCenter #MilkyWayGalaxy #StellarDistance

VizieR J/A+A/701/A270

VizieR catalogues

German Virtual Observatory Sep 27

New in the #VirtualObservatory: “Pulsation study of 176 HADS stars with OGLE” by Netzel H. et al.
https://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/515/4574
#GalacticCenter #StellarAges #EffectiveTemperature #Metallicity

VizieR J/MNRAS/515/4574

VizieR catalogues

Daniel Fischer Sep 25

JWST's first view of the most vigorously star-forming cloud in the #GalacticCenter - Sagittarius B2: https://arxiv.org/abs/2509.11771 -> Webb explores largest star-forming cloud in the Milky Way: https://esawebb.org/news/weic2520/