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.
Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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"5050 results found.
- GRB 120923A: GROND Upper limits
- GRB 120923A: Gemini afterglow detection, high-z candidate
- Konus-Wind observation of GRB 120919A
- IPN Triangulation of long GRB 120919A
- GRB 120919A: Fermi GBM detection
- Swift Trigger 533836 is a new Galactic transient
- GRB 120911A: Faulkes Telescope North observations
- GRB 120907A: Fermi GBM detection
- GRB 120907A: Swift detection of a burst with optical counterpart
- GRB 120817A: Swift detection of a burst
- GRB 120816A: BOOTES-2 observations
- GRB 120816A: ROTSE-III Optical Limits
- Konus-Wind observation of GRB 120811B
- Swift Trigger 530581: GRB 120811A or a galactic transient
- GRB 120803A: optical upper limit
- GRB 120804A: Konus-Wind and Swift/BAT joint spectral analysis
- Fermi/GBM detection of an SGR-like burst
- GRB 120804A: Swift-BAT refined analysis
- GRB 120803A: Swift detection of a possible burst
- IPN Triangulation of GRB 120728B (long/intense)
- Swift Trigger 528925 is probably a noise fluctuation
- GRB 120724A: optical observation in Maidanak observatory
- GRB 120724A: JCMT SCUBA-2 sub-mm observation
- GRB 120724A: Gemini-N tentative redshift
- GRB 120724A: FTN optical afterglow candidate
- Konus-Wind observation of GRB 120707A
- GRB 120624B: Discussion of Fermi and Swift measurements and future Swift observations
- GRB 120624A: Fermi GBM observation
- GRB 120624B: Fermi-LAT Detection
- Konus-Wind observation of GRB 120624A
- GRB 120624B: Fermi GBM detection
- IPN Triangulation of GRB 120624A (short/intense)
- IPN Triangulation of GRB 120602A (long/very bright)
- GRB 120519A: Suzaku WAM observation of the prompt emission
- GRB 120512A: Suzaku WAM observation of the prompt emission
- IPN Triangulation of GRB 120519A (short/hard)
- Fermi/GBM detection of a burst from the magnetar 1E 2259+5
- GRB 120422A: CARMA 3mm observations
- Swift detection of 4U 1630-47
- GRB 120424A: MAXI/GSC detection of a burst
- SGR1806-20, Swift-BAT refined analysis (Trigger 519868)
- Trigger 519868: Swift detection of SGR1806-20
- GRB 120404A: MASTER OT observations
- GRB 120404A: MASTER early OT limit
- GRB 120402B: Fermi GBM detection
- GRB 120401A: Swift detection of a burst
- GRB120327A - ATCA radio afterglow detection at 34GHz
- GRB 120324A: CrAO optical upper limit
- GRB 120324A, the review of the sky area in plate archives
- Trigger 518853: Swift detection of a probable Galactic transient
- IPN Triangulation of GRB 120328B (long/intense)
- GRB 120328A: Swift detection of a burst
- GRB 120327A: Swift/UVOT further analysis
- GRB 120327A: Swift-BAT refined analysis
- GRB 120327A: Enhanced Swift-XRT position
- GRB 120327A: Liverpool Telescope Observations
- GRB 120327A: Swift detection of a burst with an optical counterpart
- GRB 120326A: T17 optical observations
- GRB 120324A: CQUEAN rizY Observation
- GRB 120324A: Liverpool Telescope optical candidate
- Simultaneous optical images of Swift pointing are available by GRT
- GRB 120316A : Suzaku WAM observation of the prompt emission
- GRB 120312A, the review of the sky area in plate archives
- GRB 120312A: WHT candidate afterglow
- GRB 120311B: C88 optical limits
- GRB 120312A: Swift detection of a burst
- GRB 120224A: optical observation in Mondy observatory
- GRB 120224A: FTN optical observations
- Fermi GBM detection of an SGR-like burst
- Skynet/PROMPT observations of GRB120215A
- GRB 120213A: Enhanced Swift-XRT position
- GRB 120213A: Swift-BAT refined analysis
- GRB 120213A: Prompt enhanced Swift-XRT position
- GRB 120213A: Swift detection of a burst
- GRB 120212A: NOT optical observation
- GRB 120211A: MASTER early optical observations
- GRB 120211A - Faulkes Telescope South Observations
- Swift detection of a burst from LS I +61 303
- GRB 111225A: optical observations
- GRB 120119A: optical observations
- GRB 120119A: Swift detection of a burst with an optical counterpart
- XRF 120118A: early optical limit by "Pi of the Sky"
- GRB 120118B: MASTER optical observations
- GRB 120118B: Swift detection of a burst
- AXP 4U 1042+61: Mondy optical observations
- GRB 120116A: Mondy optical observations
- AXP 4U 0142+61: Swift-BAT refined analysis (trigger 511611)
- GRB 120106A: optical upper limit
- Swift detection of an SGR burst from AXP 4U 0142+61
- GRB 120107A: Suzaku WAM observation of the prompt emission
- GRB 120106A: Swift detection of a burst
- GRB 120102A: Swift/UVOT Detection
- GRB 120102A: Swift detection of a burst with an optical counterpart
- GRB 111228A: MASTER-Net optical photometry
- GRB111228A: Further GMG observations
- FERMI GRB111228.45: MASTER observations
- GRB111222A: GMG optical observation
- XRT GRB Catalogue now live and online
- GRB 111209A: IRTF NIR Imaging/Spectroscopy
- GRB 111204A, Swift-BAT refined analysis