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').
Advanced Search
To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.
Advanced Search Examples (click to copy):
subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"
6191 results found.
- GRB 121024A: PAIRITEL NIR Detection
- GRB 121024A: Swift-XRT refined Analysis
- GRB 121017A: Swift-XRT refined Analysis
- GRB 121012A: Fermi GBM detection
- GRB 121011A: optical observations
- GRB 121011A: Fermi-LAT detection of a burst
- GRB 121011A: Swift-XRT refined Analysis
- GRB 120804A: Late-time Chandra observation
- GRB 121001A: Swift-XRT refined Analysis
- GRB 120927A: Swift-XRT refined Analysis
- Further Swift-XRT observations of the GRB 120919A field.
- GRB 120921A: Fermi GBM detection of its 1000th GRB
- GRB 120923A: Swift-XRT refined Analysis
- GRB 120922A: Fermi GBM detection
- GRB 120922A: Swift-XRT refined Analysis
- GRB 120919A: Swift/UVOT Upper Limits
- GRB 120919A: Swift-XRT observations
- Konus-Wind observation of GRB 120919B
- GRB 120919A: Fermi GBM detection
- GRB 120916A: Fermi GBM Observation
- GRB 120916A: Fermi-LAT detection of a burst
- Corrections to the Fermi-LAT upper limits for GRB 120807A, 120908A, 120909A, and 120911A
- GRB 120913B: Fermi GBM observation
- GRB 120913A: Fermi GBM observation
- GRB 120911B: Fermi GBM observation
- GRB 120911B: Fermi-LAT detection of a burst
- GRB 120911A: Fermi GBM observation
- GRB 120911A: Swift-XRT refined Analysis
- GRB 120908A: Fermi GBM detection
- GRB 120908A: Swift Observations
- GRB 120909A: Fermi GBM observation
- GRB 120909A: Swift-XRT refined Analysis
- GRB 120907A: Swift-XRT refined Analysis
- GRB 120907A: Fermi GBM detection
- XMM observations of the short GRB120804A
- GRB 120830A: Further Swift Observations
- GRB 120830A: Swift-XRT and UVOT observations
- GRB 120830A: Fermi GBM observation
- GRB 120830A: early MASTER optical limit
- GRB 120830A: Fermi-LAT detection of a short burst
- Fermi trigger 368003226 : MASTER optical observations
- GRB 120821A: Swift/XRT observations
- GRB 120819A: GROND afterglow confirmation
- GRB 120819A: Swift-XRT refined Analysis
- GRB 120817B: Swift-XRT observations
- GRB 120817A: Swift-XRT refined Analysis
- GRB 120817B: Fermi GBM detection
- GRB 120816A: Swift-XRT refined Analysis
- GRB 120815A: Swift-XRT refined Analysis
- GRB 120811B: Fermi GBM observation
- GCN for GRB 120811C
- GRB 120811A: Swift/XRT-UVOT Obseravations
- GRB120804A: Chandra observations and afterglow detection
- GRB 120805A: Enhanced Swift-XRT position
- GRB 120811C: Swift-XRT refined Analysis
- GRB 120811C: RTT150 optical observations
- GRB 120803A: Confirmation of the X-ray afterglow
- GRB 120807A: Swift-XRT refined Analysis
- Fermi/GBM detection of an SGR-like burst
- Swift trigger 530214: uncertain if real or not
- GRB 120728A: Fermi GBM observation
- GRB 120802A: Swift/UVOT Upper Limits
- GRB 120805A: Swift-XRT refined Analysis
- GRB 120803B: Swift-XRT refined Analysis
- GRB 120804A: Swift-XRT refined Analysis
- GRB 120803A: Swift-XRT Observations
- GRB 120803A: Swift detection of a possible burst
- GRB 120802A: Swift-XRT refined Analysis
- GRB 120729A: Fermi GBM observation
- GRB 120728B: Fermi GBM detection
- Virtual Telescope observations of GRB 120729A
- T100 observations of GRB 120729A
- GRB 120729A: Swift-XRT refined Analysis
- GRB 120728A: Swift-XRT refined Analysis
- GRB 120728A: GROND observations
- GRB 120727A/Galactic source: Fermi-LAT detection of a transient source
- GRB 120724A: Swift-XRT refined Analysis
- GRB 120709A: Swift re-observation of the field of the X-ray counterpart candidate.
- GRB 120722A: Swift-XRT refined Analysis
- GRB 120716A: Fermi GBM observation
- GRB 120716A: Swift-XRT detection
- GRB 120714B: Swift-XRT refined Analysis
- GRB 120714A: GROND upper limits
- GRB 120714B: GROND confirmation of fading afterglow
- GRB 120714A: Swift-XRT refined Analysis
- GRB 120712A: Fermi GBM observation
- GRB 120712A: Swift-XRT refined Analysis
- GRB 120711B: Swift-XRT refined Analysis
- GRB 120709A: Swift/UVOT Observations
- GRB 120711A: Fermi LAT detection
- GRB 120711A: Swift-XRT observations
- GRB 120711A: Fermi GBM observation
- GRB 120709A: Fermi GBM detection
- GRB 120709A: Swift-XRT observations
- GRB 120709A: Matched filter analysis of Fermi-LAT data
- GRB 120707A: Fermi GBM Detection of a Bright Burst
- GRB 120703A: Fermi GBM detection
- GRB 120703A: Swift-XRT refined Analysis
- GRB 120701A: Swift-XRT afterglow detection and analysis
- GRB 120630A: Swift-BAT/-XRT/-UVOT refined analysis