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"27039 results found.
- GRB 140903A: P60 Optical Observations
- GRB140903A: Discovery Channel Telescope Optical Detection
- GRB 140903A: Swift-BAT refined analysis
- GRB 140903A: Swift-XRT refined Analysis
- GRB 140903A: Preliminary Swift/XRT localization
- GRB 140903A: Swift detection of a possible burst
- GRB 140901A: Fermi GBM detection
- IPN Triangulation of GRB 140901A (short/hard/very intense)
- GRB 140831A: iPTF observations of a possible short burst detected by Fermi GBM
- GRB 140829A: Fermi GBM Detection
- GRB 140829A: iPTF optical observations
- GRB 140828A, Swift-BAT refined analysis
- GRB 140828A: Fermi GBM observation
- GRB 140828A: Swift detection of a burst
- IPN Triangulation of GRB 140824B
- GRB 140818B: TLS observations
- GRB 140824A: optical upper limit in CrAO
- GRB 140824B: Swift observations
- Fermi TRIGGER_NUM 430645968: MASTER OT inside error box
- GRB 140824B: Fermi GBM Detection
- GRB 140821A: Fermi GBM Detection
- Fermi TRIGGER_NUM 430583595: MASTER OT JR011101.13+603337.5 detection
- GRB 140824A: Swift-XRT refined Analysis
- GRB 140824A: Swift-BAT refined analysis
- GRB 140824A: Swift/UVOT Upper Limits
- GRB 140824A: Swift detection of a burst
- Fermi GBM Trigger 140819576/ 430148973/ MASTER OT
- Fermi trigger 430148973: Swift-XRT observation
- GRB 140818A: GROND confirmation of afterglow candidate
- GRB140819A: Deep GROND Upper Limits
- Fermi 430148973/MASTER candidate: LCO-Sutherland observations
- Fermi trigg_num 430148973: OSN I-band observations
- GRB 140818B, Swift-BAT refined analysis
- Fermi trigg_num 430148973: bright OT inside large error box!
- GRB 140818B: Swift/UVOT Upper Limits
- GRB 140818B: Swift-XRT refined Analysis
- GRB 140818B: Fermi GBM detection
- GRB140818B : GROND afterglow candidate
- GRB 140817A: Swift/UVOT Afterglow Detection
- GRB 140818B: Swift detection of a burst
- GRB 140818A - Fermi GBM Detection
- Swift detection of SAX J1712.6-3739
- GRB 140818A: Swift-XRT and UVOT potential afterglow detection
- GRB 140818A: Correction to GCN 16702
- Konus-Wind observation of GRB 140817A
- GRB 140817A: Swift-XRT refined Analysis
- GRB 140817A: Fermi GBM Detection
- GRB 140817A: Swift-BAT refined analysis
- GRB 140817A: Swift detection of a burst
- GRB 140808A / PTFeag: VLA K-band observations
- GRB 140815A: GROND afterglow candidate
- Swift Trigger 609694 is probably not an astrophysical source
- GRB 140815A: Swift-XRT observations
- GRB 140814A: Swift-XRT and UVOT observations
- GRB 140814A: MASTER optical follow-up inspection
- GRB 140814A: Swift-XRT and UVOT observations
- GRB 140808A: Confirmation of the Swift-XRT afterglow
- GRB140809A: Fermi GBM observation
- GRB 140810A: Fermi GBM observation
- GRB140810A: Fermi-LAT detection
- Swift trigger 609139 is probably 4U 1850-03
- Swift observations of possible GRB 140809A candidate
- GRB 140809A : Virtual Telescope optical observations
- GRB 140809A (FERMI trigger 429246673): MASTER follow-up inspection
- GRB 140808A: Swift/UVOT Upper Limits
- GRB 140808A: Swift-XRT observations
- GRB 140808A: Fermi GBM detection
- GRB 140808A: optical afterglow candidate iPTF14eag
- GRB 140801A: GROND Afterglow detection, unbroken decay
- GRB140801A: Swift/XRT further observations
- GRB 140730A: GROND Upper limits
- GRB 140801A: BTA confirmation of redshift
- GRB 140801A: Swift/UVOT Upper Limits
- GRB 140801A: Swift-XRT observations
- GRB 140801A : Virtual Telescope optical observations
- GRB 140801A: Fermi GBM observation
- GRB 140801A: NOT afterglow confirmation
- IPN triangulation of GRB 140801A (Fermi trigger 428612396)
- GRB 140801A: archival upper limits on the host galaxy
- GRB 140801A (FERMI trigger 428612396): MASTER brigth OT discovery
- GRB 140730A, Swift-BAT refined analysis
- GRB 140709B: TShAO optical upper limit
- Swift Trigger 607945: possible noise event in the direction of NGC2559
- GRB 140730A: LCO-Sutherland observations
- GRB 140730A: Swift-XRT refined Analysis
- GRB 140730A: Swift/UVOT Upper Limits
- GRB 140730A: Swift detection of a burst
- Swift Trigger 607506 is probably noise
- GRB 140729A: Swift-XRT and UVOT observations
- IPN Triangulation of GRB 140729A
- GRB 140729A: Fermi-GBM detection
- GRB 140729A: Fermi-LAT detection
- Trigger 607399: Swift detection of SGR1806-20
- GRB 140723A: Swift-XRT and UVOT observations
- GRB 140723A: MASTER optical observation
- GRB 140723A: LCO-Sutherland optical candidate
- GRB 140723A: Fermi GBM detection
- IPN Triangulation of GRB 140723A
- GRB 140723A: Fermi-LAT detection
- GRB 140709B: Swift/UVOT Upper Limits