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"21393 results found.
- GRB070714B: Swift-XRT refined analysis
- GRB 070707: Swift-XRT follow-up observations
- 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
- Updated Swift/UVOT calibration
- GRB 070707: optical afterglow
- GRB 070707: object inside XRT error circle
- Swift/UVOT Observations of GRB070707
- Swift XRT observation of GRB 070707
- GRB 070429B: NIR Observations
- GRB070704: FAVOR optical observations
- GRB 070704 : Liverpool Telescope Observations
- GRB 070611: VLT observations
- GRB 070704: Swift-XRT refined analysis
- Swift/UVOT Observations of GRB070704
- GRB 070704, Swift-BAT refined analysis
- GRB 070704: Correction to GCN Circ 6594
- GRB 070704: Swift detection of a burst
- GRB 070628 Swift-UVOT Refined Analysis
- GRB 070628: NIR detection of afterglow
- GRB 070628, Swift-BAT refined analysis
- GRB 070628: TAROT La Silla observatory optical observations
- GRB 070628: Swift XRT refined analysis
- GRB 070628: Watcher Observations
- Swift UVOT Observations of GRB 070628
- GRB 070628: Swift detection of a possible burst
- INTEGRAL burst GRB070615: X-ray continued observations
- GRB 070616 : WIDGET simultaneous optical observations
- GRB 070616: Suzaku/WAM observation of the prompt emission
- GRB070621: RTT150 optical observations
- GRB 070621: VLT optical observations
- GRB 070621: Swift/UVOT Upper Limits
- Keck Laser Guide Star Adaptive Optics Imaging of GRB 070621
- GRB 070621: Swift-BAT refined analysis
- WHT observations of GRB070621
- GRB070621: Swift XRT refined analysis
- GRB 070621: Gemini South optical imaging
- GRB 070621: UVOT-enhanced XRT position
- GRB 070621: NOT observations
- GRB070621: OPTIMA-Burst optical upper limit
- GRB 070621: TAROT Calern observatory optical observations
- GRB 070621: Watcher Observations
- GRB 070621: ROTSE-III Prompt Optical Limits
- GRB 070621: Swift detection of a burst
- GMRT upper limit of GRB 070610/SWIFT J195509.6+261406 in 610 MHz
- Swift/UVOT detection of GRB070616 optical afterglow.
- GRB070616: Optical Observation by MITSuME Akeno
- GRB 070612B: Optical Observation by MITSuME Akeno
- GRB 070616, Swift-BAT further refined analysis
- GRB 070616: Swift XRT refined circular
- GRB 070616: BTA optical observations
- Swift/UVOT observations of GRB070616
- GRB 070616: TLS observation
- Swift XRT observations of the INTEGRAL burst GRB070615: Possible
- GRB 070616, Swift-BAT partial refined analysis
- GRB 070616: Swift detection of a burst
- GRB 070612B: optical observations
- UVOT Observations of INTEGRAL burst GRB070615
- SWIFT J195509.6+261406 (GRB 070610): further observations
- GRB 070612A: Rapid Decay
- GRB 070612A: Suzaku/WAM observation of the prompt emission
- SWIFT J195509.6+261406 / GRB 070610: OPTIMA-Burst observations
- GRB 070611: Watcher Observations
- Swift Trigger 282176 is Cygnus X-1
- GRB 070612A: MDM Observations
- GRB 070612B: SARA upper limit
- GRB 070612B, Swift-BAT refined analysis
- GRB 070612A, Swift-BAT refined analysis
- GRB 070612B: Swift-XRT refined analysis
- SWIFT J195509.6+261406 / GRB 070610: SWIFT continued observations
- GRB 070612B: Swift/UVOT upper limits
- GRB 070612B: FRAM limit
- GRB070612B: P60 Observations
- GRB 070612B: KAIT limits
- GRB 070612B: Swift XRT position from downlink data
- GRB 070610: TAROT Calern observatory optical observations
- GRB 070610: MITSuME OAO optical upper limit
- GRB 070612B: Swift detection of a burst
- GRB 070612: Swift detection of a burst
- GRB 070610: Swift-XRT refined analysis
- GRB 070610: TLS RRM sees flaring behaviour - Galactic transient?
- GRB 070611: Swift/UVOT Observations
- GRB 070611: Swift-XRT refined analysis
- GRB 070611, Swift-BAT refined analysis
- GRB 070610: Optical observations from OSN
- GRB 070610: Watcher Observations
- GRB 070611: ROTSE-III Detection of Late Rising Optical Counterpart
- GRB 070611; Swift-XRT position
- GRB 070611: ROTSE-III Optical Limits
- GRB 070611: Swift detection of a burst
- GRB 070610: Swift-UVOT Upper Limits
- GRB 070610: OPTIMA-Burst high-time-resolution optical observations
- GRB 070610, Swift-BAT refined analysis
- GRB 070610; Swift-XRT position
- GRB 070610: Swift detection of a burst