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"3051 results found.
- GRB 180605A: Fermi GBM observation
- IPN Triangulation of GRB 180523A
- GRB 180510B: Swift detection of a burst with an optical counterpart
- GRB 180411A: Swift-BAT refined analysis
- Konus-Wind observation of GRB 180404C
- IPN Triangulation of GRB 180404C (long)
- GRB 180404C CALET Gamma-Ray Burst Monitor detection
- Fermi GBM triggers 544628550/180405571, 544542853/180404579, 544531428/180404447 are not GRBs
- GRB 180404A: MASTER-OAFA OT observation
- GRB 180329B: Swift detection of a burst with an optical afterglow
- GRB 180324A: Enhanced Swift-XRT position
- GRB 180324A: Prompt enhanced Swift-XRT position
- GRB 180324A: Swift detection of a burst
- IPN Triangulation of GRB 180318A (long)
- GRB180316A: MASTER-IAC OT light curve
- GRB180316A: MASTER-IAC optical detection
- GRB 180205A: Mondy optical observations
- Swift J1658.2-4242: Swift BAT and XRT refined analysis
- Swift trigger 810300: MASTER-OAFA robotic report
- Swift J1658.2-4242 (trigger 810300): Swift-XRT position
- Swift Trigger 810300 is a probable new Galactic source: Swift J1658.2-4242
- GRB 180205A: Xinglong TNT optical observation
- GRB 180111A: Insight-HXMT/HE observation
- Konus-Wind observation of GRB 180111A
- GRB 180111A CALET Gamma-Ray Burst Monitor detection
- GRB 180111A: AGILE/MCAL detection
- GRB 180111A: Swift detection of a burst with an optical counterpart
- GRB 171205A: MASTER-Net OT recent photometry
- Pan-STARRS follow-up of IceCube-171106A
- GRB 171126A: Fermi GBM detection
- GRB 171108B: Insight-HXMT detection
- GRB 171115A: Swift detection of a burst
- GRB 171112A: MAXI/GSC detection
- IceCube-171106A: Swift Observations
- GRB 171010A: afterglow and SN 2017htp optical observations
- GRB 171030A: MASTER inspection of the IPN error box of the short GRB.
- GRB 171007A: Swift-XRT refined Analysis
- GRB 171004A: Swift-BAT refined analysis
- LIGO/Virgo G298048: Record of all e-MERLIN results to date on SSS17a
- IceCube-170922A: Swift-XRT observations
- LIGO/Virgo G298048: ATCA monitoring of SSS17a in NGC 4993
- LIGO/Virgo G297595: NIR Observations following GW170814
- GRB 170911A: MAXI/GSC detection
- GRB 170903A: MITSuME Okayama upper limits
- LIGO/Virgo G297595: DECam observations of BBH merger region of interest
- LIGO/Virgo G299232 ANTARES search (2)
- GRB 170830A: MAXI/GSC detection
- LIGO/Virgo G299232 TZAC/TAROT observations
- LIGO/Virgo G299232: AGILE GRID observations
- LIGO/Virgo G299232 ANTARES search
- LIGO/Virgo G298936 TAROT/TZAC observations
- LIGO/Virgo G298936: GWFUNC/CNEOST optical observations and an optical transient
- LIGO/Virgo G298048: TOROS optical counterpart search
- LIGO/Virgo G298048: HSC observations of the OT candidate of G298048
- LIGO/Virgo G298048: Subaru HSC follow-up observations
- LIGO/Virgo G298048: Galaxy-Targeted Optical Followup With Las Cumbres Observatory
- LIGO/Virgo G297595: Subaru Hyper Suprime-Cam follow-up observations
- LIGO/Virgo G297595: REM optical/NIR observations
- LIGO/Virgo G297595 : MAXI/GSC observations
- LIGO/Virgo G297595: Fermi GBM Observations
- LIGO/Virgo G297595: AGILE GRID observations
- IPN Triangulation of GRB 170805B (short/hard)
- GRB 160814A: Lomonosov BDRG gamma ray discovery
- GRB 170710B: Fermi GBM observation
- GRB 170710B: Swift-XRT and UVOT observations
- GRB 170626A: SAO RAS confirmation of OT fading
- GRB 170626A: TShAO optical observations
- GRB 170626A: SAO RAS possible OT detection
- LIGO/Virgo G288732: Pan-STARRS coverage of the Fermi/LAT candidate position
- Konus-Wind observation of GRB 170616A
- Swift Trigger 756953 is probably not an astrophysical source
- Konus-Wind observation of GRB 170607B
- GRB 170610A: MAXI/GSC detection
- IPN Triangulation of GRB 170607B
- GRB 170607B: AstroSat CZTI detection
- GRB 170607A: MASTER-Tavrida early OT observations
- GRB 170519A: TShAO and AbAO optical observations
- Swift Trigger 755873: MASTER Net optical observations
- GRB 170531A: MASTER Net job
- LIGO/Virgo G268556: optical observations and classification of Pan-STARRS1 transients
- LIGO/Virgo G268556/GW170104: Konus-Wind observations
- GRB 170524B: MASTER-OAFA observations
- IPN Triangulation of GRB 170522B (long/intense)
- Konus-Wind observation of GRB 170522A
- AXP CXOU J164710.2-455216: Fermi GBM observation
- Konus-Wind observation of GRB 170510A
- Short GRB 170428A: MASTER-OAFA final reduction of the optical observations
- GRB 170428A: Swift detection of a short burst
- Swift Trigger 750044 is probably a noise fluctuation
- Konus-Wind observation of GRB 170424A
- GRB 170412A CALET Gamma-Ray Burst Monitor detection
- Konus-Wind observation of GRB 170409A
- GRB 170409A: Fermi GBM Observation
- Fermi trigger 512347439/GRB 170327A: MASTER-SAAO possible OT detection
- GRB 170331A: Swift detection of a burst
- Konus-Wind observation of GRB 170320A
- GRB 170320A: POLAR Observation
- IPN Triangulation of GRB 170320A (long/intense)
- IceCube-170312A: MASTER follow-up observations
- LIGO/Virgo G277583: ATLAS coverage and transients over the first 2 days