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"42606 results found.
- GRB 140419A: Continued Mondy optical observations
- GRB 140515A: GROND observation of the afterglow
- GRB 140515A: Spectroscopy from the 10.4m GTC
- GRB 140515A: Optical observations from the 2.5 m NOT
- GRB 140515A: Swift-XRT refined Analysis
- GRB 140515B: MAXI/GSC detection
- GRB 140515A: KAIT Optical Upper Limit
- GRB 140515A: Gemini-North imaging
- GRB 140515A: Swift/UVOT Upper Limits
- GRB 140515A: Enhanced Swift-XRT position
- GRB 140515A: Gemini-N redshift
- Trigger 599041: Swift detection of SFXT IGR J16479-4514
- GRB 140515A: Swift detection of a burst
- GRB 140508A: VLA detection
- Konus-Wind observation of GRB 140512A
- GRB 140423A: AAO optical upper limits
- GRB 140512A: Continued UVOT Observations
- GRB 140512A: Fermi GBM detection
- GRB 140512A: Xinglong TNT optical observation
- GRB 140508A: Mondy upper limit
- GRB 140512A: Swift-BAT refined analysis
- GRB140512A : GROND observations
- GRB 140512A: Swift-XRT refined Analysis
- GRB 140512A: Enhanced Swift-XRT position
- Swift Observations of GRB 140508A
- GRB 140512A: Optical observations from the 2.5 m NOT
- GRB 140428A: GROND afterglow confirmation
- GRB 140512A: Mondy optical detection
- GRB 140512A: MASTER OT decay and early light curve
- GRB 140512A: Swift detection of a burst with an optical counterpart
- GRB 140512A: MASTER optical observations
- GRB 140423A: Mondy optical observations
- GRB 140508A: Continued RATIR Optical and NIR Observations
- Fermi GBM Trigger 140429551 - Detection of a burst from SGR 1806-20
- GRB 140508A: HCT spectroscopy
- GRB 140508A: Swift/UVOT Detection
- GRB 140509B: MAXI/GSC detection
- GRB 140509A: Swift/UVOT Detection and photo-z
- GRB 140509A: Swift-BAT refined analysis
- VHE gamma-ray observations by MAGIC of SWIFT Trigger 596958
- GRB 140509A: Swift-XRT refined Analysis
- GRB 140508A: RATIR Optical and NIR Observations
- GRB 140508A: Optical Observations via Virtual Telescope
- Konus-Wind observation of GRB 140508A
- GRB 140509A: Enhanced Swift-XRT position
- GRB 140508A: Swift-XRT observations
- GRB 140508A: WHT spectroscopy
- GRB 140509A: Swift detection of a burst with an optical counterpart
- GRB 140508A: NOT photometry and spectroscopy
- GRB 140508A: SAO RAS and MASTER photometric and spectroscopic observations
- GRB 140508A: 1.23m CAHA BVRI-band observations
- GRB 140508A: iPTF optical transient candidate
- IPN triangulation of GRB 140508A
- GRB 140508A: Fermi GBM detection
- Konus-Wind observation of GRB 140506A
- GRB 140502A: ISON-NM early optical limit
- GRB 140506A: Fermi GBM Detection
- GRB 140506A: Swift/UVOT Detection
- GRB 140506A: Swift-BAT refined analysis
- GRB 140506A: VLT/X-shooter spectroscopy
- GRB 140506A: Swift-XRT refined Analysis
- GRB 140506A: Enhanced Swift-XRT position
- GRB 140506A: Swift detection of a burst with an optical counterpart
- Konus-Wind observation of GRB 140423A
- GRB 140430A: iTelescope.Net T16 Optical Observation
- GRB 140430A: r'-band STELLA-I observations
- GRB 140502A: Swift/UVOT Upper Limits
- GRB 140502A: Swift-BAT refined analysis
- GRB 140502A: Swift-XRT refined Analysis
- GRB 140502A: Enhanced Swift-XRT position
- GRB 140430A: BVR-band IAC80 observations
- Swift Trigger 597860 is probably not a GRB
- GRB 140502A: Fermi GBM observation
- GRB 140502A: Swift detection of a burst
- GRB 140430A: Swift-BAT refined analysis
- GRB 140501A: Fermi GBM detection
- GRB 140430A: Swift/UVOT Observations
- GRB 140430A: Swift-XRT refined Analysis
- GRB 140430A: VATT Optical Observations
- GRB 140430A: Enhanced Swift-XRT position
- GRB 140430A: VLT/X-shooter redshift
- GRB 140430A: NOT optical observations
- GRB 140430A : Liverpool Telescope optical afterglow observations
- GRB 140428A: GROND observations
- GRB140430A: Swift detection of a burst with an optical counterpart
- GRB 140428B: Fermi GBM observation
- Konus-Wind observation of GRB 140428B
- GRB 140428A: Swift-BAT refined analysis
- GRB 140423A: RTT150 optical observations
- IPN Triangulation of GRB 140428B (short/hard)
- Trigger 597570: Swift detection of SGR 1806-20
- GRB 140428A: 1.5m OSN I-band detection
- GRB 140428A: Keck redshift estimate
- GRB 140428A: Keck detection of a red optical afterglow candidate
- GRB 140428A: NOT observations
- GRB 140428A: Swift-XRT detection of a source
- GRB 140428A: Swift Detection of a Possible Burst
- GRB 140423A Third epoch pODI photometry
- GRB 140423A: Continued RATIR Optical and NIR Observations
- GRB 140413A: GROND Afterglow Confirmation