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"3037 results found.
- GRB 121108A: Swift-XRT refined Analysis
- GRB 121108A: Xinglong TNT upper limit
- GRB 121108A: Swift detection of a burst
- GRB 121031A: Fermi GBM detection
- GRB 121024A: MITSuME Ishigakijima upper limits
- IPN Triangulation of short hard GRB 121011B
- GRB 120913B: REM NIR early time detection
- GRB 120908A: MAXI/GSC detection
- GRB 120830A: early MASTER optical limit
- IPN Triangulation of short GRB 120830A
- Fermi trigger 368003226 : MASTER optical observations
- GRB 120821A: GROND upper limits
- Swift Trigger 530581: GRB 120811A or a galactic transient
- GRB120805A: Liverpool Telescope observations
- GRB 120804A: Gemini-North observations
- GRB 120802A: Swift detection of a burst
- Trigger 529076: Swift possible detection of SwJ1910.2-0546
- GRB 120716A: Swift/XRT position consistent with that of the optical counterpart
- Swift trigger 524642 / SwJ1910.2-0546
- Swift Trigger 524642 is Swift J1910.2-0546
- GRB 120528B: MAXI/GSC detection
- GRB 120521C - NOT optical limits
- GRB 120510B/Fermi Trigger 358364818: MASTER possible OT candidate
- GRB 120510A: MAXI/GSC detection of a burst
- IPN Triangulation of GRB 120427A
- Swift detection of 4U 1630-47
- GRB 120424A: MAXI/GSC detection of a burst
- GRB 120404A: optical observations in Mondy observatory
- GRB 120403B: Swift-BAT refined analysis
- GRB 120402A: MASTER follow up observations
- GRB 120328B: Pi of the Sky simultaneous upper limits
- GRB120326A: TNT optical observation
- GRB120326A: IAC80 observations
- Simultaneous optical images of Swift pointing are available by GRT
- GRB 120312A: CrAO optical upper limit
- GRB 120312A: WHT candidate afterglow
- GRB 120311B: C88 optical limits
- GRB 120302A: GROND detection of an afterglow candidate
- GRB 120229A, Swift-BAT refined analysis
- GRB 120224A: optical observation in Mondy observatory
- Swift Trigger 516027 is CC Eri
- GRB 120224A: Swift detection of a burst
- GRB 1202019A: optical observation in Mondy observatory
- GRB 120219A: MITSuME Okayama Optical upper limits
- GRB 120215A: Swift-BAT refined analysis
- GRB 120215A: Swift detection of a burst
- GRB 120211A: Swift-BAT refined analysis
- Swift detection of a burst from LS I +61 303
- GRB 120127A: MAXI/GSC detection of a probable GRB
- AXP 4U 1042+61: Mondy optical observations
- GRB 120116A: Optical observations at Crni Vrh
- AXP 4U 0142+61: Swift-BAT refined analysis (trigger 511611)
- Swift detection of an SGR burst from AXP 4U 0142+61
- GRB 111228A: MASTER-Net optical photometry
- GRB 111228A: Optical and NIR observations with Kanata telescope
- GRB 111225A: Lightbuckets Optical Observations
- GRB 111228A: X-shooter spectroscopy
- GRB111228A: MITSuME Akeno photometry of the optical afterglow
- GRB 111228A: GMG optical observation
- GRB111228A: MITSuME Okayama Optical Observation
- GRB 111228A: Swift detection of a burst with an optical counterpart
- Trigger 510075 is not a GRB
- GRB 111215A: MASTER-Net optical prompt and follow up observations
- GRB111210A: MITSuME Okayama J-band upper-limit
- GRB 111209A, Swift-BAT refined analysis
- GRB 111209A: Swift detection of a long burst with an optical counterpart
- GRB 111121A: Suzaku WAM observation of the prompt emission
- IPN Triangulation of GRB 111113A (short/hard/intense)
- Continued Skynet observations of GRB111107A
- Trigger 506913: Swift detection of Swift J1922.7-1716 and its optical counterpart
- GRB 111022B: MASTER OT observations
- GRB 111029A: KAIT optical limits
- GRB 111029A: optical upper limit
- GRB 111029A: Swift detection of a burst
- GRB 111026A: Swift detection of a burst
- GRB 111022A: MITSuME Akeno Optical upper limits
- GRB 111022A: MASTER-Net early limit
- GRB 111018A: GROND Upper Limits
- GRB 110928A: Swift-XRT observations
- Fermi GBM triggers 110923481, 110924391 and 110925200 are not GRBs
- GRB 110921A: Swift-XRT refined Analysis
- MAXI/GSC detection of a short soft X-ray transient
- GRB 110825A: Suzaku WAM observation of the prompt emission
- GRB 110827A: Swift detection of a burst
- GRB110820A: MITSuME Ishigakijima Optical Upper Limits
- GRB 110818A: Optical afterglow and redshift from VLT/X-shooter
- IPN triangulation of GRB 110808B (short/hard/intense)
- GRB 110726A: Swift-XRT refined Analysis
- GRB110731A: MOA optical observations of the steeply fading afterglow
- GRB 110801A: MASTER OT observations
- AXP 4U 0142+61: Fermi GBM detection
- INTEGRAL Weak trigger #6331: GRT Optical Observation
- AXP 4U 0142+61: Swift-BAT refined analysis
- Swift detection of a SGR-like burst from the AXP 4U 0142+61
- Konus-Wind observation of GRB 110721A
- GRB 110721A: Fermi-LAT detection
- GRB 110721A: Fermi GBM detection
- Swift J1822.3-1606 : Fermi GBM observation
- Swift J1822.3-1606: A Probable New SGR in Ground Analysis of BAT Data
- Konus-Wind observation of GRB 110708B