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"5822 results found.
- IceCube-170922A: First Optical observations of the Neutrino Trigger by MASTER Global Net and 25 IceCube alerts inspection.
- GRB 180709A: Optical limits
- GRB 180709A: COATLI Optical Observations
- Fermi GBM triggers 552488966/180705548 and 552490104/180705561 are not GRBs
- GRB 180705A: MASTER optical observation
- GRB 180626C / Fermi trigger 551697835: MASTER inspection
- Konus-Wind observation of GRB 180626C
- IPN Triangulation of GRB 180626C (short)
- IPN Triangulation of GRB 180626B (short)
- GRB 180624A: Swift detection of a burst
- GRB 180620B: VLT/X-shooter redshift
- GRB 180620B: Swift detection of a burst with an optical counterpart
- GRB 180618A: Swift detection of a burst with an optical counterpart
- GRB 180614A: MASTER observation
- GRB 180602A: MITSuME Akeno optical upper limits
- GRB 180526A: AstroSat CZTI detection
- GRB 180514A: CrAO/ZTSH optical observations and afterglow candidate
- GRB 180514A: GOTO Optical Observations
- GRB 180514A: Swift detection of a burst
- Swift trigger 831888: misidentification of 4U 1416-62
- GRB 180510B: VLT/X-shooter observations
- GRB 180510A: Swift detection of a burst
- LIGO/Virgo G299232: LOFAR follow-up
- GRB 180416A: Fermi GBM detection
- GRB 180410A: Swift detection of a burst or a Galactic transient.
- GRB 180402A: ISON-NM early optical limits
- GRB 180404A: LCO FTS observations
- Fermi GBM triggers 544440014/180403389 and 544451446/180403521 are not GRBs
- Konus-Wind observation of GRB 180402A
- GRB 180402A: Fermi GBM detection
- GRB 180402A: KAIT Optical Upper Limit
- GRB 180402A: Swift detection of a possibly short burst
- Swift Trigger 819863 is not a GRB
- GRB 180325A: Global MASTER-Net OT prompt observations
- GRB 180324A: Swift detection of a burst
- IPN Triangulation of GRB 180318A (long)
- IPN Triangulation of GRB 180317A (short/hard)
- GRB180316A: MASTER-IAC OT light curve
- GRB180316A: MASTER-IAC optical detection
- Swift Trigger on MAXI J1820+070
- GRB 180314A: Swift detection of a burst with an optical counterpart
- GRB 180305A: AstroSat CZTI detection
- Swift detection of MAXI J1820+070
- GRB 180305A CALET Gamma-Ray Burst Monitor detection
- Konus-Wind observation of GRB 180305A
- GRB 180305A: Fermi GBM detection
- GRB 180305A: Fermi-LAT detection
- Konus-Wind observation of GRB 180223A
- IPN Triangulation of GRB 180223A (long)
- MAXI J1813-095 source: AbAO optical observations
- GRB 180204A: 15 GHz upper limits from AMI
- GRB 180112A: AstroSat CZTI detection
- Trigger 809374: Swift detection of a possible non-burst faint source
- Trigger 809217: Swift trigger on RS CVn Star HD 8357
- GRB 180205A: AbAO optical observations
- LIGO/Virgo G298048 GRAWITA: VST-ESO PARANAL follow up of AT2017gfo
- GRB 180115A: MITSuME Akeno optical upper limits
- GRB 171230A CALET Gamma-Ray Burst Monitor detection
- GRB 171229A CALET Gamma-Ray Burst Monitor detection
- VLBA detection of GRB 171205A
- GRB 180102A: Swift-BAT refined analysis
- IceCube-170922A: Konus-Wind upper limits
- GRB 171222A: NOT Optical Afterglow
- GRB 171222A: Swift detection of a burst
- Swift Trigger 797070: KAIT Optical Observations
- GRB 171205A: ALMA observations
- GRB 171211A: Swift detection of a possibly short burst
- GRB 171209A: Lulin 1m telescope observations
- GRB 171205A: MASTER-Net OT recent photometry
- GRB 171205A: iTelescope optical observations
- GRB 171205A: Mondy optical observations
- GRB 171205A: SAO-RAS optical observations
- GRB 171209A: Enhanced Swift-XRT position
- GRB 171205A: VLA detection
- Swift Trigger 796098 is probably a noise peak near M31
- LIGO/Virgo GW170817: Chandra X-ray brightening of the counterpart 108 days since merger
- GRB 171205A: CHILESCOPE optical observations
- GRB 171205A: TNG NIR detections
- GRB 171205A: NOEMA detection of a bright mm afterglow
- GRB 171205A: Swift/UVOT Detection
- Pan-STARRS follow-up of IceCube-171106A
- GRB 171124A: Swift-XRT observations
- GRB 171120A: Swift detection of a burst
- GRB 171115A: MITSuME Okayama optical upper limits
- GRB 171115A: MITSuME Akeno optical upper limits
- GRB 171030A: MASTER inspection of the IPN error box of the short GRB.
- GRB 171102B: MITSuME Akeno optical upper limits
- Fermi-GBM triggers due to Swift J0243.6+6124
- GRB 171027A: LCO 1-m telescope observations
- GRB 171027A: MASTER-OAFA (Argentina) early prompt optical observations
- Fermi GBM trigger 530617076/171025401 is not a GRB
- Swift Trigger 781740 is not a burst
- GRB 171020A: Mini-MegaTORTORA upper limits on simultaneous optical emission
- GRB 171020A: Swift detection of a burst
- Trigger 779762: Swift detection of Vela X-1
- GRB 171010A: optical observations
- GRB 171007A: Swift-XRT refined Analysis
- GRB 171004A: Correction to RATIR Astrometry and Photometry
- GRB 171004A: RATIR Optical and NIR Observations
- GRB 171004A: Swift detection of a burst