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"14827 results found.
- GRB 170607B: AstroSat CZTI detection
- LIGO/Virgo G288732: Fermi-LAT detection of a weak candidate
- GRB 170607A: Correction on the possible host galaxy identification
- GRB 170607A: Swift/UVOT Detection
- GRB 170607A: NOT optical afterglow detection
- GRB 170607A: Swift detection of a burst with a bright optical counterpart
- GRB 170529A: AstroSat CZTI detection
- GRB 170604A: GTC spectroscopic redshift
- Swift Trigger 755873: a possible GRB
- GRB 170604A: Swift detection of a burst
- GRB 170531B: Swift/UVOT Detection
- GRB 170531B: MASTER Net optical counterpart refind position and magnitude
- GRB 170531B: MASTER Net OT detection
- GRB 170531B: Swift detection of a burst
- GRB 170531A: Swift detection of a burst
- GRB 170511A: AstroSat CZTI detection
- GRB 170527A: Fermi GBM detection
- GRB 170526A: Swift detection of a burst
- Konus-Wind observation of GRB 170524B
- GRB 170511A CALET Gamma-Ray Burst Monitor detection
- GRB 170524B: Swift detection of a burst
- IPN Triangulation of GRB 170522A
- GRB 170511A: MAXI/GSC detection
- GRB 170524A: Swift detection of a burst (or possible new SGR)
- Konus-Wind observation of GRB 170522A
- GRB 170522A: Fermi-LAT detection
- GRB 170522A: Fermi GBM detection
- GRB 170514A CALET Gamma-Ray Burst Monitor detection
- GRB170519A, Swift-UVOT Detection
- GRB 170519A: BOOTES-5/JGT early optical detection
- GRB 170519A: Swift detection of a burst with an optical counterpart
- GRB 170510A CALET Gamma-Ray Burst Monitor detection
- LIGO/Virgo G277583: UH88/SNIFS classification of ATLAS and PS1 transients
- GRB 170510A: Swift-XRT afterglow detection
- GRB 170516A: Swift detection of a burst
- Swift Trigger on AXP CXOU J164710.2-455216
- GRB 170514A: Fermi GBM detection
- GRB 170510A: AstroSat CZTI(Veto) detection
- Konus-Wind observation of GRB 170510A
- LIGO/Virgo G284239: H.E.S.S. very-high energy gamma-ray follow-up
- GRB 170510A: Fermi-LAT detection
- GRB 170428A CALET Gamma-Ray Burst Monitor detection
- GRB 170428A: GTC spectroscopic redshift of candidate host galaxy
- GRB 170428A: RATIR Afterglow Confirmation
- GRB 170428A: GROND detection of the afterglow
- Konus-Wind observation of GRB 170428A
- Swift Trigger 750337 is probably a noise fluctuation
- GRB 170428A: Swift detection of a short burst
- GRB170426.95 MASTER-Net OT detection
- Swift Trigger 750096 is probably a noise fluctuation
- Swift Trigger 750044 is probably a noise fluctuation
- Konus-Wind observation of GRB 170424A
- GRB 170424A: Fermi GBM detection
- GRB 170424A: Fermi-LAT detection
- GRB 170423A: Fermi GBM detection
- GRB 170412A CALET Gamma-Ray Burst Monitor detection
- Swift trigger 748858: Swift BAT, XRT, and UVOT refined analysis
- GRB 170419B: Swift detection of a burst
- GRB 170419A: Swift detection of a burst
- Swift Trigger 748858: a possible GRB
- Konus-Wind observation of GRB 170409A
- GRB 170402A: AstroSat CZTI detection
- GRB 170409A: Fermi-LAT detection
- GRB 170403B CALET Gamma-Ray Burst Monitor detection
- GRB170405A, Swift-UVOT Detection
- GRB 170405A, Swift-BAT refined analysis
- Konus-Wind observation of GRB 170405A
- Trigger 745966: Swift detection of 4U1850-03
- GRB 170405A: Watcher optical detection
- GRB 170405A: Fermi-LAT detection
- GRB 170405A: Swift detection of a burst with an optical counterpart
- GRB 170402A CALET Gamma-Ray Burst Monitor detection
- GRB 170330A CALET Gamma-Ray Burst Monitor detection
- GRB 170325A: optical observations, possible OT/host detection
- Konus-Wind observation of GRB 170330A
- Fermi-LAT Gamma-ray Observations of IceCube-170321
- GRB 170330A: AstroSat CZTI detection
- IceCube-170321A: Swift-XRT observations
- GRB 170330A: Swift/UVOT Detection of a Fading Afterglow
- Konus-Wind observation of GRB 170329A
- GRB 170329A: AstroSat CZTI detection
- Fermi trigger 512347439/GRB 170327A: MASTER-SAAO possible OT detection
- GRB 170331A: Swift detection of a burst
- GRB 170330A: Swift detection of a burst
- GRB 170329A: Fermi GBM detection
- GRB 170329A: Fermi-LAT detection
- GRB 170325A, Swift-BAT detection of a short GRB
- INTEGRAL pointed follow-up of IceCube-170321A
- LIGO/Virgo G275697: AMI Large Array Search for a Radio Afterglow
- Search for counterpart to IceCube-170321A with ANTARES
- GRB 170317A: POLAR observation
- GRB 170318B: Swift detection of a burst
- GRB 170315A: POLAR observation
- GRB 170318A: Swift detection of a burst
- IceCube-170312A: MASTER follow-up observations
- GRB 170317A: Swift/UVOT Detection
- GRB 170317A: Swift detection of a burst with an optical counterpart
- LIGO/Virgo G275697: Swift-XRT source 23 no longer fading
- LIGO/Virgo G277583: ATLAS17cck is likely a minor planet
- LIGO/Virgo G277583: GROND follow up of ATLAS17cck