Tag

Gamma Rays

All articles tagged with #gamma rays

physics-and-chemistry29 days ago•17 min saved

Photon’s TikTok Through Einstein’s Rules: Axions and Tiny Lorentz Violations May Explain a 300 TeV Travel</title>

Physicists propose GRB 221009A’s extreme 300 TeV photons survived a two‑billion‑light‑year trip by briefly converting into axion‑like particles, with a tiny Lorentz‑invariance violation enabling a “fast lane.” A predicted one‑hour gap between lower‑energy photons and the 300 TeV burst matched an independent Chinese observation, offering empirical support and a potential probe of quantum gravity.

via Gizmodo|

#axion-like-particles #gamma-rays #grb-221009a

space-and-spaceflight1 month ago•16 min saved

Sharp Gamma-Ray Hint Sparks Fresh Dark Matter Debate

A Chinese Academy of Sciences team reports a sharp gamma-ray line in 15.5 years of Fermi Gamma-ray Space Telescope data, arguing it provides strong direct evidence for dark matter in the form of weakly interacting massive particles (WIMPs). The authors say the signal fits expectations for WIMP annihilation, but gamma-ray lines can arise from instrumental or astrophysical sources, so confirmation will require further data and independent verification as new gamma-ray observatories come online.

via Gizmodo|

#dark-matter #fermi-gamma-ray-space-telescope #gamma-rays

science2 months ago•2 min saved

Milky Way Hosts a Proton PeVatron Far More Energetic Than the LHC

Astronomers have identified LHAASO J1912+1014u as a proton PeVatron in the Milky Way, accelerating protons to PeV energies—well beyond the Large Hadron Collider—based on multiwavelength data from Fermi-LAT, FUGIN, and Chandra that rule out electrons as the gamma-ray source; the exact engine remains unknown, but such galactic PeVatrons may be common and help explain the origin of the most energetic cosmic rays.

via Gizmodo|

#cosmic-rays #gamma-rays #lhaaso-j19121014u

science2 months ago•5 min saved

Dark Matter Could Decay into Gravitons and Glow as Gamma Rays

A new proposal suggests dark matter may decay into gravitons, which could convert to photons via the Gertsenshtein effect as they travel through large-scale magnetic fields in intergalactic filaments, producing an excess gamma-ray signal. If true, this would shift searches from galactic centers to intergalactic space and could be tested with Fermi data today, with future missions like the Advanced Particle-astrophysics Telescope boosting sensitivity by an order of magnitude.

via ScienceAlert|

#cosmic-filaments #dark-matter #gamma-rays

space3 months ago•7 min saved

Twin Supernova Remnants Hint at Exploding Stellar Siblings

Using 16 years of Fermi gamma-ray data, astronomers found gamma rays from the faint remnant G189.6+3.3 overlapping the Jellyfish Nebula, supporting a binary-star origin where both exploded and left two interacting remnants about 6,000 light-years away in Gemini; ages range ~8–9k and 20k–110k years, with simulations showing such dual explosions are plausible and possibly linked to PeVatron acceleration.

via NASA Science (.gov)|

#binary-stars #fermi-lat #gamma-rays

space4 months ago•74 min saved

Magnetar-powered gamma glow lights up a distant supernova

NASA’s Fermi detected gamma rays from the luminous core-collapse supernova SN 2017egm (NGC 3191, about 440 million light-years away), supporting the idea that a newborn magnetar—an ultra‑magnetized neutron star—powers the explosion. A magnetar wind nebula and related particle interactions could boost gamma-ray production and reprocess energy into visible light, explaining the unusually bright display; gamma rays begin to leak out as debris expands, with the early light curve matching models though late-time fading remains puzzling. The study also notes the upcoming Cherenkov Telescope Array could detect similar events up to ~500 million light-years, advancing understanding of magnetar engines. The work appeared in Astronomy & Astrophysics on May 20, 2026.

via Space|

#gamma-rays #magnetar #neutron-star

space7 months ago•4 min saved

Milky Way Center Signals Point to Excited Dark Matter

Astronomers say a single excited dark matter model could explain three puzzling signals from the Milky Way's center—the 511-keV gamma-ray line, a 2 MeV continuum, and unusually high ionisation in the Central Molecular Zone—potentially guiding future space missions to test dark matter behavior.

via BBC Sky at Night Magazine|

#astrophysics #dark-matter #excited-dark-matter

space8 months ago•3 min saved

Novae Unveiled: Real-Time Interferometry Reveals Multi-Stage Ejections and Gamma Rays

Astronomers using the CHARA Array and other telescopes captured real-time images of two novae (V1674 Herculis and V1405 Cassiopeiae), revealing complex, multi-stage gas outflows and gamma-ray emissions—showing that nova explosions are not single blasts and linking surface nuclear processes to the geometry of ejected material and high-energy radiation.

via Futurism|

#binary-star #gamma-rays #interferometry

space8 months ago•26 min saved

Novae Unleash Dual Jets: High-Res Images Rewrite Stellar Explosions

High-resolution CHARA Array images of 2021 novae V1674 Herculis and V1405 Cassiopeiae reveal complex, jet-driven eruptions in binary white-dwarf systems, including perpendicular outflows and a delayed ejection likely tied to a common-envelope phase. The gamma-ray signals observed by NASA’s Fermi coincide with internal shocks in the debris, linking surface nuclear reactions to high-energy radiation and challenging the idea of novae as simple spherical shells. These findings, published in Nature Astronomy, position novae as natural laboratories for extreme physics.

via ZME Science|

#binary-system #gamma-rays #interferometry

space8 months ago•6 min saved

High‑Res Imaging Reveals Dual Ejecta in Nova Explosions

Scientists using the CHARA Array’s near-infrared interferometry captured high‑resolution images of two novae (V1674 Herculis and V1405 Cassiopeiae), showing non‑spherical, interacting ejecta and fast/slow evolution, with a gamma-ray connection that challenges the idea of a single impulsive explosion.

via WIRED|

#ejecta #gamma-rays #interferometry

science8 months ago•8 min saved

Gamma-Ray Tests Tighten Lorentz-Invariance Bounds, Not Break Special Relativity

New analysis of gamma-ray flares from pulsars, active galactic nuclei, and gamma-ray bursts finds no energy-dependent speed of light, placing stricter bounds on Lorentz-violating effects predicted by some quantum gravity theories. The results tighten the allowed violations by about 1.5 orders of magnitude and offer a framework for integrating new data into the SME; in short, SR remains consistent, while the search for quantum-gravity signatures continues.

via Hackaday|

#gamma-rays #lorentz-invariance #quantum-gravity

science10 months ago•3 min saved

Scientists Claim First Direct Evidence of Dark Matter Detection

Scientists may have found the first direct evidence of dark matter using gamma rays detected by NASA's Fermi Telescope, which could mark a major breakthrough in understanding this elusive substance, possibly confirming the existence of WIMPs and their annihilation in the Milky Way's center.

via ScienceDaily|

#dark-matter #fermi-telescope #gamma-rays

science11 months ago•4 min saved

Scientists Recreate Cosmic Fireballs at CERN to Uncover Gamma-Ray Mysteries

Scientists at CERN recreated cosmic jet conditions using particle accelerators to investigate missing gamma-rays from blazars, finding that plasma beam instabilities are too weak to explain the phenomenon, which supports the idea of relic magnetic fields in intergalactic space. This experiment provides new insights into cosmic jet physics and the universe's magnetic history.

via Space|

#black-holes #cern #cosmic-fireballs

science11 months ago•3 min saved

Mysterious Galactic Glow May Reveal Dark Matter Secrets

A new study using advanced simulations suggests that the mysterious gamma-ray glow at the center of the Milky Way could be explained by the distribution of dark matter shaped by the galaxy's early mergers, reigniting the debate over dark matter's role in this cosmic phenomenon.

via SciTechDaily|

#cosmological-simulations #dark-matter #galactic-center

science11 months ago•3 min saved

Hidden Glow in the Milky Way Suggests Dark Matter Activity

New simulations suggest that the faint glow at the center of the Milky Way could be a signature of dark matter, which may have a flattened, egg-like shape influenced by the galaxy's violent history, bringing scientists closer to confirming dark matter's existence.

via Space|

#cosmology #dark-matter #fermi-telescope