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"27018 results found.
- GRB 140622A: Swift detection of a short burst
- GRB 140620A: Swift/UVOT Detection
- GRB 140606B / iPTF 14bfu: SAO RAS optical observations
- GRB 140620A: Swift-XRT observations
- GRB 140620A / iPTF14cva: Fermi GBM observations
- Fermi 424934131 / iPTF14cva: Discovery and Redshift of Optical Afterglow
- GRB 140619B: Swift-XRT observations
- GRB 140619A: Swift-BAT refined analysis
- GRB 140610A: TShAO optical upper limit
- GRB 140619B: Fermi-LAT Detection
- GRB 140619B: Fermi GBM detection of a short GRB
- GRB 140619A: Swift/UVOT Observations
- GRB 140619A: Swift-XRT refined Analysis
- GRB 140619A: Swift detection of a burst with a possible optical counterpart
- Swift trigger 601928 is V490 Cep: BAT+XRT refined analysis.
- Swift-BAT trigger 601928: Detection of a possible outburst from V490 Cep
- GRB 140614B: MOSFIRE Ks-band nondetection
- GRB 140614B: Swift-XRT refined Analysis
- GRB 140614B: Swift-BAT refined analysis
- GRB 140614A: Swift-BAT refined analysis
- GRB 140614A: X-shooter redshift
- GRB 140614B: Swift/UVOT Upper Limits
- GRB 140614B: RATIR Optical and NIR Observations
- GRB 140614A: Swift/UVOT Upper Limits
- GRB 140614A: Swift-XRT refined Analysis
- GRB 140614B: Swift detection of a burst
- GRB 140614A: GROND afterglow candidate
- GRB 140614A: Swift detection of a burst
- GRB 140611A: Swift-XRT observations
- GRB 140610A: Swift-XRT refined Analysis
- GRB 140606B / iPTF 14bfu: MOSFIRE NIR imaging
- GRB 140610A: Fermi GBM Detection
- GRB 140610A: RATIR Optical and NIR Observations
- GRB 140610A: Swift-BAT refined analysis
- GRB 140610A: MASTER optical observations
- GRB 140610A: Swift/UVOT Upper Limits
- Konus-Wind observation of GRB 140610A
- GRB 140610A: Swift-XRT observations
- GRB 140610A: Swift detection of a burst
- GRB 140606B: Swift XRT refined analysis
- GRB 140607A: Swift-BAT refined analysis
- GRB 140606B: Swift/UVOT Upper Limits
- GRB140606B/iPTF14bfu: Discovery Channel Telescope Optical Detection
- GRB 140606B: Swift XRT position
- GRB 140607A: Swift detection of a burst
- GRB 140606B: Fermi GBM detection
- Fermi 423717114: Additional P48 and P60 observations
- Fermi423717114: iPTF optical transient candidates
- GRB 140606A: Swift/UVOT Upper Limits
- Swift Trigger 600914 is noise
- GRB 140606A: Swift-BAT refined analysis
- GRB 140606A: Swift detection of a short hard burst
- Swift Trigger 600914 is probably a noise fluctuation
- GRB 140528A: Fermi GBM Detection
- GRB 140529A BAT refined analysis
- GRB 140529A: Swift/UVOT Upper Limits
- GRB 140529A: Swift-XRT afterglow detection.
- IPN Triangulation of GRB 140528A
- Chandra late-time observations of GRB140515A
- Swift Trigger 600114 in M31: UVOT Observations
- Swift trigger 600114 is not an outbursting X-ray source
- Swift Trigger 600114: Optical spectroscopy from GTC
- Swift Trigger 600114: Preliminary BAT analysis
- Swift Trigger 600114 in M31: Archival and Prompt UVOT Imaging
- Swift detection of a bright X-ray source in M31
- Fermi GBM trigger 422752719/ 140525971 is not a GRB
- Swift detection of SFXT IGR J17544-2619
- Swift trigger 599860 probably not real
- GRB 140523A: Fermi-LAT detection
- GRB 140523A: Fermi GBM detection
- GRB 140521A: Fermi GBM Detection
- GRB 140521A: Swift-BAT refined analysis
- GRB 140521A: AROMA-N Optical Observation
- GRB 140516A: further Swift-XRT analysis
- GRB 140521A: MASTER optical observations
- GRB 140521A: Swift detection of a burst
- GRB 140518A: T100 observations
- GRB 140518A: Continued RATIR Optical and NIR Observations
- GRB 140512A: MASTER prompt and afterglow optical observations
- GRB 140518A, Swift-BAT refined analysis
- GRB 140518A: Swift-XRT refined Analysis
- GRB 140518A: Skynet GORT Detections of the Optical Afterglow
- GRB 140518A: Swift/UVOT Upper Limits
- GRB 140518A: RATIR Optical and NIR Observations
- GRB 140518A: P60 i-/z-band detections
- GRB 140518A: KAIT optical candidate
- GRB 140518A: Swift detection of a burst
- GRB 140516A: RATIR Optical and NIR Observations
- GRB 140516A: Swift/UVOT Upper Limits
- GRB 140516A: Swift-BAT refined analysis
- GRB 140516A: Swift-XRT refined Analysis
- GRB 140516A: MASTER early optical observations
- GRB 140516A: Swift detection of a short burst
- GRB 140515A: Swift-BAT refined analysis
- GRB 140515A: GROND observation of the afterglow
- GRB 140515A: Swift-XRT refined Analysis
- GRB 140515A: Gemini-North imaging
- GRB 140515A: Swift/UVOT Upper Limits
- Trigger 599041: Swift detection of SFXT IGR J16479-4514
- GRB 140515A: Swift detection of a burst