GCN Circulars
GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
17858 results found.
- GRB 241108A: Swift-XRT observations
- GRB 241108A: Swift ToO observations
- GRB 241030A: TESS observations
- GRB 241105A: EP-FXT follow-up observations
- GRB 241105A: SVOM/GRM observation
- GRB 241105a: PRIME near-infrared upper limits
- GRB 241105A: Swift/UVOT Detection
- GRB 241105A: Swift/BAT-GUANO refined analysis of short burst with extended emission
- GRB 241030A: optical afterglow detection from the INAF Asiago Observatory
- GRB 241105A: BOOTES-7 optical detection
- GRB241105A: Fermi GBM Observation of a Short Burst with Extended Emission
- GRB 241105A: Swift-XRT afterglow detection
- GRB 241104A: Swift-XRT observations
- GRB 241105A: Swift ToO observations
- GRB 241105A: Swift/BAT-GUANO arcminute localization of a short burst
- GRB 241104A: Swift ToO observations
- GRB 241030A: GRBAlpha detection
- EP241103a: GIT optical upper limit
- EP241103a: GOTO optical upper limit
- EP241103a: Swift XRT detection and improved X-ray position
- GRB 241030A: Swift-UVOT observations of the optical prompt flare
- GRB 241030A: Rapid release of TESS data.
- Swift GRB 241101A: Global MASTER-Net observations report
- GRB 241101A: FRAM-ORM optical limit
- GRB 241101A: Swift-BAT refined analysis
- GRB 241030B: Swift-XRT refined Analysis
- GRB 241030A / EP241030a: GMG possible spectroscopic redshift at z ~ 1.4
- GRB 241101A: Swift detection of a burst
- GRB 241030B: Montarrenti Observatory optical upper limit
- GRB 241030A / EP241030a: FTW Optical and NIR observations of the optical counterpart
- GRB 241030A: Fermi GBM Observation
- GRB 241030B: LCOGT Optical Upper Limits
- GRB 241030B: Swift-BAT refined analysis
- GRB 241030A: Swift-BAT refined analysis
- GRB 241030B: Swift/UVOT Detection
- GRB 241029A: LCO optical detection
- Swift GRB241030.77: Global MASTER-Net observations report
- GRB 241030B: SVOM/GRM observation
- GRB 241030B : MITSuME Akeno optical upper limits
- GRB 241030A: COLIBRI Continuing Detection of the Afterglow
- GRB 241030B: COLIBRÍ Upper Limits on the Optical Counterpart
- GRB241030B: Fermi GBM Observation
- GRB 241030A: detection of the bright optical counterpart in ATLAS forced photometry
- GRB 241030B: Enhanced Swift-XRT position
- GRB 241030B: optical observations from the INAF Asiago Observatory
- EP241021a: Swift-UVOT detection
- GRB241030B: GRANDMA/TAROT Upper Limit
- GRB 241030A: Swift-XRT refined Analysis
- GRB 241030B: AKO Optical Afterglow Detection
- GRB 241030B: Nanshan/HMT optical afterglow detection
- GRB 241030B: SVOM/ECLAIRs detection of a burst
- GRB 241030B: Prompt enhanced Swift-XRT position
- Konus-Wind detection of GRB 241030A
- GRB 241030B: Swift detection of a burst
- GRB 241030A: Fermi-LAT detection
- GRB 241030A: AKO Optical Afterglow Detection
- Swift GRB 241030A: Global MASTER-Net observations report
- GRB 241030A: Swift/UVOT Detection
- EP 241021a: further Swift-XRT observations and X-ray counterpart detection
- GRB 241030A: SVOM/GRM observation
- GRB 241026A: Swift-BAT refined analysis
- GRB 241030A: SVOM/C-GFT optical observations
- GRB 241030A: Multiband optical detection with Mephisto
- GRB 241030A: SVOM/VT optical afterglow observations
- GRB 241025A: The discovery of a BdHN I from data of Swift, Fermi, SVOM and Einstein Probe telescopes
- GRB 241030A : MITSuME Akeno optical afterglow detection
- GRB 241030A: Enhanced Swift-XRT position
- GRB 241030A: TRT optical observations
- GRB 241030A: ULL-ASTRO-MASTER detection of a bright optical counterpart with the LCOGT 40-cm telescope at McDonald Observatory
- GRB 241030A: COLIBRÍ Detection of the Bright Optical Counterpart
- GRB 241030A: Swift detection of a burst with a bright optical counterpart
- GRB 241026A: Swift/UVOT Upper Limits
- GRB 241029A: Swift-XRT observations
- GRB 241029A: Swift ToO observations
- GRB 241026A: the 100th GRB detected by GRBAlpha
- Konus-Wind detection of GRB 241025A
- GRB 241026A: GECAM detection
- GRB 241026A: SVOM/GRM observation
- GRB 241025A: Swift/UVOT Detection
- GRB 241026A: GROWTH-India Telescope optical observations
- GRB 241026A Fermi GBM Analysis
- GRB 241026A: J-band observations with WINTER
- GRB 241025A: SAO RAS optical observations
- GRB 241026A: Las Cumbres optical detection
- GRB 241025A: Mondy optical observations
- GRB 241026A: Swift-XRT refined Analysis
- GRB 241026A: Enhanced Swift-XRT position
- GRB 241026A: KAIT optical observations
- GRB 241026A: COLIBRÍ Detection of the Optical Counterpart
- GRB 241026A: SAO RAS observations of possible optical afterglow
- GRB 241026A: Prompt enhanced Swift-XRT position
- GRB 241026A: Swift detection of a burst
- Swift GRB241026.95: Global MASTER-Net observations report
- GRB241025A: 1.3m DFOT optical afterglow detection
- GRB 241025A: GROWTH-India Telescope optical observations
- GRB 241025A: COLIBRÍ Detection of the Afterglow
- GRB 241025A: Swift-XRT refined Analysis
- GRB 241025A: Fermi GBM Observation
- IPN triangulation of GRB 241022A (short/hard)
- LIGO/Virgo/KAGRA S241009l: Upper limits from Swift/BAT-GUANO