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"32532 results found.
- Fermi GRB 240305C: Global MASTER-Net observations report
- GRB 240305A: Swift/BAT-GUANO arcminute localization of a burst
- GRB 240218A: ALMA detection
- GRB 240218A: Chandra Detection and Jet Break Confirmation
- Konus-Wind detection of GRB 240227A (short/hard)
- GRB 240303B: VZLUSAT-2 detection
- GRB 240229A: VZLUSAT-2 detection
- Improved IPN triangulation of GRB 240227A (short)
- IPN triangulation of GRB 240229A
- GRB240218A: ATCA observation of the radio counterpart
- Transient EPW20240219aa: Optical observations with LDT
- Konus-Wind detection of GRB 240303B
- Swift Trigger 1218645: Another detection of Swift J151857.0-572147
- IPN triangulation of GRB 240303B
- Swift J151857.0-572147: Swift-BAT refined analysis
- GRB 240303B: Fermi GBM Detection
- GRB 240225B: Swift-XRT afterglow detection
- Swift detection of Swift J151857.0-572147
- GRB 240303B: CALET Gamma-Ray Burst Monitor detection
- Swift GRB 240303A: Global MASTER-Net observations report
- Swift J151857.0-572147: Confirmation of a new galactic transient
- GRB 240225B: Glowbug gamma-ray detection
- IceCube-240229A: Upper limits from a search for additional neutrino events in IceCube
- GRB 240225C: Glowbug gamma-ray detection
- GRB 240225A (short): Glowbug gamma-ray detection
- GRB 240229A: DDOTI Upper Limits on the Afterglow
- GRB 240218A: NOEMA upper limit
- GRB 240229A: CALET Gamma-Ray Burst Monitor detection
- GRB 240225B: further SAO RAS optical observations
- Fermi GRB 240229A: Global MASTER-Net observations report
- GRB 240225B: Swift ToO observations
- Konus-Wind detection of GRB 240225B (long)
- GRB 240225B: VLT/X-shooter redshift
- GRB 240225B : MITSuME Akeno optical afterglow candidate detection
- GRB 240225B: 3.6m DOT observation
- GRB 240225B: WINTER near-IR observations and upper limits
- GRB 240225B: SAO RAS optical observations
- GRB 240226A: GRBAlpha detection
- GRB 240225B: Mondy afterglow observations
- Fermi GRB 240227A: Global MASTER-Net observations report
- GRB 240225B: Liverpool Telescope afterglow observations
- Swift J1727.8-1613 (GRB 230824A): Madrona Peak Observatory - optical follow-up
- IPN triangulation of GRB 240227A (short)
- GRB 240225B: Liverpool Telescope optical afterglow observations
- GRB 240225B: NOT optical observations
- GRB 240218A: CMO SAI NIR upper limit
- Fermi GRB 240226A: Global MASTER-Net observations report
- Fermi Gamma-ray Burst Monitor trigger 730618809/240226236 is not a GRB
- GRB 240225B: Nanshan/HMT optical afterglow detection
- GRB 240225B: CALET Gamma-Ray Burst Monitor detection
- Transient EPW20240219aa: Kp-band imaging observations with NIRES
- Transient EPW20240219aa: J-band upper limits from WINTER
- GRB 240225C: CALET Gamma-Ray Burst Monitor detection
- GRB 240225B: GOTO detection of a candidate optical afterglow
- Transient EPW20240219aa: REM optical/NIR upper limits
- GRB 240225C: GRBAlpha detection
- GRB 240222A: ATCA radio observations
- GRB 240225B: AstroSat CZTI detection
- GRB 240225B: Tiled Swift observations
- Transient EPW20240219aa: Xinglong-2.16m optical upper limit
- GRB 240218A: VLA detection
- GRB 240222A: GRBAlpha detection
- Transient EPW20240219aa: GECKO: LOAO Optical Upper Limits
- Transient EPW20240219aa: 7DT Optical Upper Limits
- VLA X-band observation of EPW20240219aa
- Transient EPW20240219aa: Mondy optical observations
- Transient EPW20240219aa: upper limit in gamma-ray range from SPI-ACS/INTEGRAL observations
- Insight-HXMT/HE Sub-Threshold Detection of Transient EPW20240219aa
- Swift BAT Sub-Threshold Detection of EPW20240219aa
- Transient EPW20240219aa: Liverpool Telescope non-detection and limiting magnitude
- GRB 240222A: GECAM detection of a burst
- GRB 240222A: Swift-BAT refined analysis
- GRB 240222A: Fermi GBM Observation
- GRB 240222A: Swift/UVOT Upper Limits
- Fermi GBM Sub-Threshold Detection of EPW20240219aa as a likely GRB
- Swift GRB 240222A: Global MASTER-Net observations report
- Fermi GRB 240222A: Global MASTER-Net observations report
- GRB 240222A: REM optical and NIR early-time observations
- GRB 240218A: MeerLICHT upper limits
- GRB 240216A: Glowbug gamma-ray detection
- GRB 240215B: Fermi GBM Observation
- GRB 240218A: LBT H-band detection
- GRB 240218A: Swift-BAT refined analysis
- Fermi GRB 240220A: Global MASTER-Net observations report
- Konus-Wind detection of GRB 240218A
- GRB 240218A: VLT/X-shooter redshift of z = 6.782
- GRB 240218A: Fermi GBM Detection
- GRB 240215A: Fermi GBM Observation
- GRB 240216A: GRBAlpha detection
- GRB 240215B: GRBAlpha detection
- IPN triangulation of GRB 240209A
- GRB 240218A: VLT/FORS2 z-band detection
- GRB 240218A: REM detection of a NIR afterglow candidate
- GRB 240213A: GRBAlpha detection
- GRB 240218A : r-band upper limit from Observatoire de Haute-Provence
- GRB240218A: VLT/X-shooter upper limits
- Fermi GRB 240216A: Global MASTER-Net observations report
- GRB 240215A: Tiled Swift observations
- GRB 240215A: Swift/BAT-GUANO localization of a burst
- GRB 240209A: Classification of AT2024cew/GOTO24pw as Type Ia-pec supernova