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"
2724 results found.
- Fermi trigger No 583567803 Global MASTER-Net observations report
- Fermi trigger No 583327924 Global MASTER-Net observations report
- GRB 190626B: Fermi GBM Final Real-time Localization
- Fermi trigger No 583111521 Global MASTER-Net observations report
- Fermi trigger No 582886211 Global MASTER-Net observations report
- Fermi trigger No 582856902 Global MASTER-Net observations report
- Fermi trigger No 582615488 Global MASTER-Net observations report
- GRB 190613B: AstroSat CZTI detection
- GRB 190611B: AstroSat CZTI detection
- Konus-Wind observation of GRB 190613B
- Fermi trigger No 582159815 Global MASTER-Net observations report
- GRB 190611B: CALET Gamma-Ray Burst Monitor detection
- GRB 190613B: Insight-HXMT/HE detection
- Konus-Wind observation of short/hard GRB 190610A
- Konus-Wind observation of GRB 190611B
- Fermi trigger No 582115625 Global MASTER-Net observations report
- GRB 190613B: Fermi GBM observation
- GRB 190611B: BALROG localization (Fermi Trigger 581986074 / GRB 190611950)
- IPN Triangulation of GRB 190611B
- GRB 190613B: BALROG localization (Fermi Trigger 582115625 / GRB 190613449)
- GRB 190613B: Swift detection of a burst with an optical counterpart
- GRB 190613B: Fermi GBM Final Real-time Localization
- GRB 190613A: Fermi GBM Final Real-time Localization
- GRB 190611B: Fermi GBM detection
- Fermi trigger No 581889628 Global MASTER-Net observations report
- Fermi trigger No 581882394 Global MASTER-Net observations report
- GRB 190609A: Fermi GBM Final Real-time Localization
- Fermi trigger No 581719018 Global MASTER-Net observations report
- Fermi trigger No 581645543 Global MASTER-Net observations report
- Fermi trigger No 581469752 Global MASTER-Net observations report
- GRB 190605A: Fermi GBM Final Real-time Localization
- Fermi trigger No 581281470 Global MASTER-Net observations report
- Konus-Wind observation of extremely bright GRB 190530A
- GRB 190525A: AstroSat CZTI detection
- LIGO/Virgo S190521r: CNEOST follow-up observations
- Fermi GRB190525.03 Global MASTER-Net observations report
- GRB 190525A: Fermi GBM Final Real-time Localization
- LIGO/Virgo S190521g: No optical counterpart from SVOM/GWAC observations.
- IGO/Virgo S190521g: Coverage and upper limits from MAXI/GSC observations
- LIGO/Virgo S190512at: SVOM/GWAC-F60A observations
- LIGO/Virgo S190519bj: MAXI/GSC Observations
- LIGO/Virgo S190519bj Global MASTER-Net observations report
- Fermi GRB190517.81 Global MASTER-Net observations report
- LIGO/Virgo S190513bm : TAROT-Calern and TAROT-Chile (TCA/TCH)/GRANDMA observation report.
- Fermi GRB190514.67 Global MASTER-Net observations report
- LIGO/Virgo S190513bm: Lick/KAIT Follow-Up Observations
- LIGO/Virgo S190510g: Further KMTNet observation of DECam-GROWTH and DESGW candidates
- LIGO/Virgo S190513bm Global MASTER-Net observations report
- LIGO/Virgo S190510g: Pan-STARRS and ATLAS observations and candidates
- LIGO/Virgo S190512at Global MASTER-Net observations report
- LIGO/Virgo S190510g: DOAO Observation
- LIGO/Virgo S190510g: KMTNet observation of DECam-GROWTH and DESGW candidates
- LIGO/Virgo S190510g: Las Cumbres Observatory Galaxy Targeted Counterpart Search
- LIGO/Virgo S190510g: Dabancheng/HMT Follow-Up Observations
- LIGO/Virgo S190510g: Xinglong/Schmidt Follow-Up Observations
- LIGO/Virgo S190510g: SOAR/Goodman follow-up observations
- LIGO/Virgo S190510g: CNEOST Follow-Up Observations
- LIGO/Virgo S190510g: Lick/KAIT Follow-Up Observations
- LIGO/Virgo S190510g: Lulin Optical Follow-up Observations
- LIGO/Virgo S190425z: CAHA-GRANDMA Observation of the Swift UVOT Source
- Konus-Wind observation of GRB 190501A
- LIGO/Virgo S190510g: HSC Y-band follow-up observation
- Fermi GRB190510.12 Global MASTER-Net observations report
- LIGO/Virgo S190510g Global MASTER-Net observations report
- Fermi GRB190507.97 Global MASTER-Net observations report
- Fermi GRB190507.27 Global MASTER-Net observations report
- IceCube-190504A: MASTER optical monitoring analysis
- Fermi GRB190505.05 Global MASTER-Net observations report
- Fermi GRB190504.68 Global MASTER-Net observations report
- LIGO/Virgo S190503bf Global MASTER-Net observations report
- IceCube-190503A: Lick/KAIT Follow-Up Observations
- Fermi GRB190429.74 Global MASTER-Net observations report
- LIGO/Virgo S190426c: YAHPT Optical Observation
- LIGO/Virgo S190426c: MASTER analysys of GRAWITA transients
- LIGO/Virgo S190426c: OAJ-GRANDMA observation report
- LIGO/Virgo S190426c: DDOTI/OAN Optical Observations
- LIGO/Virgo S190426c: COATLI Optical Observations of Galaxies
- LIGO/Virgo S190426c: MMT Follow-Up Observations
- LIGO/Virgo S190426c: Lick/KAIT Follow-Up Observations
- LIGO/Virgo S190426c: CNEOST Optical Observations
- LIGO/Virgo S190425z: CNEOST Optical Observations
- LIGO/Virgo S190426c: Optical Wide-field Search with the Zwicky Transient Facility
- LIGO/Virgo S190425z: BOOTES-5/JGT observations of galaxies
- LIGO/Virgo S190425z: GRANDMA follow-up observations with Les Makes-T60, AZT-8 and Abastumani-T70
- LIGO/Virgo S190426c: SAO optical observation
- LIGO/Virgo S190425z: Further MMT Follow-Up Observations
- LIGO/Virgo S190425z: COATLI Observations of Galaxies
- LIGO/Virgo S190426c Global MASTER-Net observations report
- LIGO/Virgo S190425z: YAHPT Optical Observation
- LIGO/Virgo S190425z: Las Cumbres Observatory Galaxy Targeted Counterpart Search
- LIGO/Virgo S190425z: KMTNet Observation
- LIGO/Virgo S190425z: GRAWITA TNG observations of ZTF19aarzaod
- LIGO/Virgo S190425z: Las Cumbres Observatory Galaxy Targeted Counterpart Search
- LIGO/Virgo S190425z: ZTF19aarykkb Imaging from Las Cumbres Observatory
- LIGO/Virgo S190425z: J-GEM optical follow-up observations with Subaru/FOCAS
- LIGO/Virgo S190425z: Candidates from the Zwicky Transient Facility
- LIGO/Virgo S190408an: Gaia Photometric Alerts transient candidates
- LIGO/Virgo S190425z: MMT Follow-Up Observations
- LIGO/Virgo S190425z: Lick/KAIT Follow-Up Observations
- LIGO/Virgo S190425z: INTEGRAL SPI-ACS prompt observation