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"14826 results found.
- GRB 240226A: Fermi GBM Final Real-time Localization
- Transient EPW20240219aa: REM optical/NIR upper limits
- GRB 240225C: GRBAlpha detection
- GRB 240225C: AstroSat CZTI detection
- GRB 240225B: AstroSat CZTI detection
- GRB 240225B: MAXI/GSC detection
- Transient EPW20240219aa: Xinglong-2.16m optical upper limit
- GRB 240218A: VLA detection
- GRB 240225A: Swift/BAT-GUANO detection of a short burst
- GRB 240222A: GRBAlpha detection
- Transient EPW20240219aa: 7DT Optical Upper Limits
- 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
- Fermi GBM Sub-Threshold Detection of EPW20240219aa as a likely GRB
- EPW20240219aa is Likely a GRB Event
- GRB 240222A: Swift detection of a burst
- GRB 240222A: Fermi GBM Final Real-time Localization
- GRB 240218A: MeerLICHT upper limits
- GRB 240216A: Glowbug gamma-ray detection
- GRB 240218A: LBT H-band detection
- GRB 240220A: Fermi GBM Final Real-time Localization
- Konus-Wind detection of GRB 240218A
- GRB 240218A: VLT/X-shooter redshift of z = 6.782
- GRB 240218A: Fermi GBM Detection
- 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
- Gamma-ray flaring activity from the blazar 1ES 1959+650 observed by the Fermi-LAT
- GRB 240213A: GRBAlpha detection
- GRB 240218A : r-band upper limit from Observatoire de Haute-Provence
- GRB 240218A: Swift detection of a burst
- GRB 240215C: Fermi GBM Final Real-time Localization
- GRB 240215B: Swift/BAT-GUANO detection of a burst outside the coded FOV
- GRB 240216A: Fermi GBM Final Real-time Localization
- GRB 240213A: Glowbug gamma-ray detection
- GRB240209A: OHP/T193 detection of the GOTO afterglow candidate AT2024cew / GOTO24pw
- GRB 240214A/1H 0451-560: MAXI/GSC detection
- GRB 240213A: Fermi GBM Final Real-time Localization
- GRB 240209A: NOEMA non-detection of AT2024cew / GOTO24pw counterpart candidate
- GRB 240209A: NOT photometry of the AT2024cew / GOTO24pw counterpart candidate
- GRB 240209A: GOTO optical counterpart candidate
- Konus-Wind detection of GRB 240204A
- Konus-Wind detection of GRB 240205A (short)
- GRB 240209A: Fermi GBM Final Localization
- IPN triangulation of GRB 240205A (short)
- GRB 240205B: PRIME near infrared detection
- GRB 240205A (short): Glowbug gamma-ray detection
- GRB 240205B: AstroSat CZTI detection
- Konus-Wind detection of GRB 240205B (long / very soft)
- GRB 240207A: Fermi GBM Final Real-time Localization
- Konus-Wind detection of GRB 240125A
- GRB 240205B: CALET Gamma-Ray Burst Monitor detection
- GRB 240205B: BOOTES-6 optical afterglow follow-up
- GRB 240205B: ATCA detection of radio counterpart
- GRB 240205B: REM detection of the optical/NIR afterglow
- GRB 240204A: AstroSat CZTI detection
- GRB 240204A : OHP/T193/T120 optical afterglow fading detection
- GRB 240205B: GECAM detection of a long burst
- GRB 240205B: BOOTES-7 optical afterglow follow-up
- GRB 240205B: MASTER OT J232550.14-550704.6 counterpart detection
- GRB 240205B: Swift detection of a burst
- GRB 240205B: Fermi GBM Final Real-time Localization
- GRB 240205A: Fermi GBM Final Real-time Localization
- GRB 240204a: Liverpool Telescope optical afterglow detection
- GRB 240204A: optical afterglow detection with LCOGT 1m telescopes at Sutherland and Teide Observatories
- GRB 240204A: Swift detection of a burst
- IceCube-240204A - IceCube observation of a high-energy neutrino candidate track-like event
- GRB 240204A: Fermi GBM Final Real-time Localization
- Konus-Wind detection of GRB 240124B
- Konus-Wind detection of GRB 240123C
- IPN triangulation of GRB 240124B
- GRB 240201A: AstroSat CZTI detection
- IPN triangulation of GRB 240125B (short)
- GRB 240129A: Swift/BAT-GUANO detection of a burst outside the coded FOV
- IPN triangulation of GRB 240125A (short)
- GRB 240128A: Glowbug gamma-ray detection
- GRB 240128A: GRBAlpha detection
- GRB 240128A: CALET Gamma-Ray Burst Monitor detection
- GRB 240128A: MAXI/GSC detection
- GRB 240125A: GRBAlpha detection
- GRB 240123C: GRBAlpha detection
- GRB 240122A: ATCA detection of radio counterpart
- GRB 240127A: Fermi GBM Final Real-time Localization
- GRB 240125A: CALET Gamma-Ray Burst Monitor detection
- GRB 240125A: AstroSat CZTI detection of a short burst
- GRB 240124B: AstroSat CZTI detection
- GRB 240123C: AstroSat CZTI detection
- GRB 240125B: Fermi GBM Final Localization
- GRB240122A: PRIME near infrared detection
- GRB 240123A: Glowbug gamma-ray detection
- GRB 240125A (short): Glowbug gamma-ray detection
- GRB 240123B: Swift/BAT-GUANO detection of a long burst
- GRB 240123A: GRBAlpha detection
- GRB 240122B: CALET Gamma-Ray Burst Monitor detection