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"23156 results found.
- GRB 070810B: Swift detection of a short burst
- GRB 070810: Swift detection of a burst
- GRB 070809, Swift-BAT refined analysis
- GRB 070809: Swift detection of a short burst
- GCN Swift XRT update position notices and enhanced position circulars
- GRB 070808, Swift-BAT refined analysis
- GRB070808: Optical observations with KANATA
- GRB070808 - SDSS Pre-Burst Observations
- GRB 070808: Swift detection of a burst
- GRB061121A: PROMPT Observations
- GRB070805 XRT and UVOT afterglow candidate
- Swift trigger on 4U 1700-377 while star tracker loss-of-lock
- GRB 070805, Swift-BAT refined analysis
- GRB 070805: Swift/UVOT initial analysis
- GRB 070805: Swift detection of a burst
- Swift detection of a outburst from SAX J1810.8-2609
- GRB 070802, Swift-BAT refined analysis
- GRB 070802: LCO I-band candidate
- GRB 070802: GROND J band candidate
- GRB 070802: Swift detection of a burst
- GRB 070731, Swift-BAT refined analysis
- Konus-A observation of GRB 070729
- Intense burst from SGR 1806-20 detected on July 27
- GRB 070729, Swift-BAT refined analysis
- GRB 070729: Magellan NIR Observations
- GRB 070729: Swift detection of a short hard burst
- GRB 070724B: Swift-XRT afterglow likely candidate
- GRB 070724B: Suzaku WAM observation of the prompt emission
- Konus-Wind observation of GRB 070724B
- GRB 070724b: First Gamma Ray Burst Localization by SuperAGILE onboard
- GRB 070724: P60 and Gemini Observations
- Swift/UVOT refined analysis of GRB070724
- Short-Hard GRB070714B: PROMPT Observations
- GRB 070724, Swift-BAT refined analysis of a short burst
- GRB 070724: Swift detection of a burst
- Swift/UVOT observations of GRB070721B optical afterglow.
- GRB 070721B, Swift-BAT refined analysis
- GRB 070721A, Swift-BAT refined analysis
- GRB 070721B: Swift detection of a burst
- GRB 070721: Swift detection of a possible burst
- GRB 070714B: Swift/BAT and Suzaku/WAM joint spectral analysis
- GRB 070714B : Suzaku WAM observation of the prompt emission
- GRB 070714A: Swift-BAT T_zero
- GRB070714B: TNG NIR observations
- Erratum : Suzaku WAM observation of GRB 070704
- GRB 070616: No Evidence for I Band Afterglow
- GRB 070714B, Swift-BAT refined analysis of the short hard burst
- GRB 070714A, Swift-BAT refined analysis
- GRB 070714 : Liverpool Telescope optical counterpart ?
- GRB 070714: Swift detection of a bright burst, possibly short
- Swift detection of a possible burst (Trigger 284850)
- GRB 070704: RTT150 optical observations
- GRB 070704: Suzaku/WAM observation of the prompt emission
- Konus-Wind observation of GRB 070707
- GRB 070707: A long GRB detected by INTEGRAL
- GRB 070707: A long GRB detected by INTEGRAL
- GRB 070429B: NIR Observations
- GRB070704: FAVOR optical observations
- GRB 070704 : Liverpool Telescope Observations
- GRB 070704, Swift-BAT refined analysis
- GRB 070704: Swift detection of a burst
- GRB 070626: Suzaku/WAM observation of the prompt emission
- GRB 070626: IPN localization and Konus spectrum of a bright long burst
- GRB 070628, Swift-BAT refined analysis
- GRB 070628: TAROT La Silla observatory optical observations
- GRB 070628: Swift XRT refined analysis
- GRB 070628: Swift detection of a possible burst
- GRB 070612A: Allen Telescope Array Observations
- OT20050728 was not an optical GRB afterglow
- GRB 070616 : WIDGET simultaneous optical observations
- GRB 070616: Suzaku/WAM observation of the prompt emission
- GRB070621: RTT150 optical observations
- GRB 070621: Swift-BAT refined analysis
- Observations of GRB070612A at Calar Alto
- GRB 070621: TAROT Calern observatory optical observations
- GRB 070621: Swift detection of a burst
- GRB 070612A: TNG optical observations
- Swift/UVOT detection of GRB070616 optical afterglow.
- GRB 070612A: NOT observations
- GRB070616: Optical Observation by MITSuME Okayama
- GRB 070616: BTA optical observations
- Swift/UVOT observations of GRB070616
- GRB 070616, Swift-BAT partial refined analysis
- GRB 070616: Swift detection of a burst
- GRB 070615: A long GRB detected by INTEGRAL
- GRB 070612A: Super-LOTIS observations
- GRB 070612A: Suzaku/WAM observation of the prompt emission
- GRB070612A: MITSuME Okayama Observation
- Swift Trigger 282176 is Cygnus X-1
- GRB 070612A: MDM Observations
- GRB 070612B, Swift-BAT refined analysis
- GRB 070612A, Swift-BAT refined analysis
- GRB 070612B: KAIT limits
- GRB 070610: TAROT Calern observatory optical observations
- GRB 070610: MITSuME OAO optical upper limit
- GRB 070612B: Swift detection of a burst
- GRB070612 - SDSS Pre-Burst Observations
- GRB 070612: Swift detection of a burst
- GRB 070610: TLS RRM sees flaring behaviour - Galactic transient?
- GRB 070611, Swift-BAT refined analysis