GCN Circulars
GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"21093 results found.
- LIGO/Virgo S190425z: Lick/KAIT Follow-Up Observations
- LIGO/Virgo S190425z: further analysis of INTEGRAL data
- LIGO/Virgo S190425z: MAXI/GSC Observations
- LIGO/Virgo S190425z: Hobby-Eberly Telescope VIRUS observations of target galaxies.
- LIGO/Virgo S190425z: SAGUARO follow-up observations
- LIGO/Virgo S190425z: INTEGRAL prompt observation
- LIGO/Virgo S190425z Global MASTER-Net observations report
- Fermi GRB190425.09 Global MASTER-Net observations report
- LIGO/Virgo S190421ar: TAROT-GRANDMA observation report.
- LIGO/Virgo S190421ar: Lick/KAIT Follow-Up Observations
- GRB 190422A: Swift/UVOT Upper Limits
- LIGO/Virgo S190408an: Liverpool Telescope follow-up imaging observations
- LIGO/Virgo S190421ar: MAXI/GSC Observations
- Swift GRB190422.96 Global MASTER-Net observations report
- Fermi GRB190422.96 Global MASTER-Net observations report
- Fermi GRB190422.67 Global MASTER-Net observations report
- LIGO/Virgo S190421ar: Fermi-GBM Observations
- LIGO/Virgo S190421ar Global MASTER-Net observations report
- AT LIGO-Virgo S190421ar: AGILE GRID observations
- LIGO-Virgo S190421ar: AGILE MCAL observations
- LIGO/Virgo S190408an: INTEGRAL follow-up observations
- Fermi GRB190420.98 Global MASTER-Net observations report
- LIGO/Virgo S190412m: SVOM/GWAC observations of the initial skymap
- Fermi GRB190419.41 Global MASTER-Net observations report
- Fermi trigger 576241792 / GRB 190406B: MASTER optical observation
- Fermi GRB190418.92 Global MASTER-Net observations report
- GRB 190406B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 576241792)
- GRB 190326A: Swift XRT and UVOT follow-up observations
- Fermi GRB190417.46 Global MASTER-Net observations report
- LIGO/Virgo S190412m: TAROT-GRANDMA observation report.
- Fermi GRB190415.17 Global MASTER-Net observations report
- LIGO/Virgo S190412m: Palomar Gattini-IR Wide-field Infrared Follow-up
- LIGO/Virgo S190412m: GOTO optical coverage - no notable counterparts
- LIGO/Virgo S190412m: J-GEM optical/NIR follow-up observations
- LIGO/Virgo S190412m: Fermi-GBM Observations
- LIGO/Virgo S190412m: MAXI/GSC Observations
- LIGO-Virgo S190412m: AGILE GRID observations
- LIGO/Virgo S190408an: ATLAS observations of the S190412m skymap
- LIGO/Virgo S190412m: Hobby-Eberly Telescope VIRUS observations of target galaxies.
- LIGO/Virgo S190412m: MASTER early alert observation
- LIGO/Virgo S190408an: GROND Observations of MASTER OT J154209.55-431742.2
- LIGO/Virgo S190408an: Pan-STARRS observations and transients in the skymap
- IceCube-190331A: Swift-XRT Follow-up Observations
- GRB 190409A: ground analysis reveals a likely spurious event
- LIGO/Virgo S190408an: MASTER OT J231043.63+470956.4 BOOTES-4 and 10.4m GTC follow-up observations
- LIGO/Virgo S190408an: MAXI/GSC Observations
- LIGO/Virgo S190408an: GRAWITA optical observations of MASTER OT J231043.63+470956.4
- LIGO/Virgo S190408an: CALET Observations
- LIGO/Virgo S190408an: TMTS Optical Observation
- LIGO/Virgo S190408an: DDOTI/OAN Optical Observations
- LIGO/Virgo S190408an: HMT optical observations
- LIGO/Virgo S190408an: MASTER 3 OT's more detection
- LIGO-Virgo S190408an: further AGILE GRID observations after T0
- LIGO/Virgo S190408an: SAGUARO follow-up observations
- LIGO/Virgo S190408an: MASTER OT detection
- LIGO/Virgo S190408an: KMTNet observation
- LIGO-Virgo S190408an: AGILE GRID observations
- LIGO/Virgo S190408an: MASTER Global Robotic Net optical observations
- LIGO-Virgo GW S190408an: J-GEM optical/NIR follow-up observations
- LIGO-Virgo S190408an: AGILE MCAL observations
- GRB 190404C: Swift-XRT afterglow detection
- Fermi TriggNum 576054086 (GRB 1904204.29) / MASTER OT J071404.52+550304.2: CrAO optical observations
- Hard Fermi GRB190404.29/TriggNum576054086: MASTER optical counterpart discovery near PGC020455
- GRB 190404C: Swift-XRT observations
- Swift GRB 190331B: Further Swift-XRT observations
- GRB190404C: GROWTH-India discovery of optical counterpart
- GRB 190404B: Tiled Swift observations
- GRB 190330A: MITSuME Akeno and Okayama optical upper limits
- GRB 190331B: BOOTES-3/YA optical observations
- GRB 190331B: Swift observations of a ground-detected burst
- Fermi-LAT Gamma-ray Observations of IceCube-190331A
- IceCube-190331A: MASTER optical follow-up observations
- GRB 190331B: Swift ToO observations
- MAGIC follow-up of the X-ray flares of LS I +61�303 dete
- GRB 190326A: 2.2m CAHA telescope optical limit
- Swift Trigger 895479: Detection of GRO J2058+42
- GRB 190326A: Swift-BAT refined analysis - a soft-short GRB or an SGR
- Swift Trigger 895257: Detection of GRO J2058+42 in outburst
- GRB 190324A: Swift/UVOT Observations
- GRB190324A: MASTER OT observations
- Further Chandra observations of GW170817 ~581-583 days since merger
- GRB 190324A: Swift-XRT observations
- SWIFT GRB190324.95 Global MASTER-Net observations report
- SWIFT GRB190323.85 Global MASTER-Net observations report
- Swift detection of LS I +61 303
- Correction: Chandra observations of GW170817 ~581 days since merger
- Chandra observations of GW170817 ~581 days since merger
- Swift Trigger 894268: Detection of GRO J2058+42 in outburst
- GRB 190114C: photometric detection of a SN component
- GRB 190320A: Swift/UVOT Upper Limits
- GRB190320A: MASTER GRB counterpart decay
- SWIFT GRB190320.05 Global MASTER-Net observations report
- GRB 190320A: Swift-XRT observations
- Fermi trigger 574140965 / GRB190313.15: MASTER Global Robotic Net optical observation
- GRB 190311A: Swift/UVOT Detection
- GRB 190311A: Mondy optical observations
- GRB 190311A: Liverpool Telescope observations
- GRB 190311A: NOT optical counterpart
- GRB190305A: MASTER Global Robotic Net optical observation
- GRB190311A: OAO observations