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"5386 results found.
- GRB 060605: Swift-XRT Team refined analysis
- GRB 060605: RTT150 optical observations
- GRB 060605: Swift detection of a burst with optical counterpart
- GRB 060605: ROTSE-III Detection of Optical Counterpart
- GRB060502b: optical observations
- GRB 060526: REM observations
- GRB 060526: MDM-2.4m Observations
- GRB 060515: Super-LOTIS Observations
- GRB 060515: Swift detection of a burst
- GRB 060512: P60 Observations
- GRB060512 - SDSS Pre-Burst Observations
- GRB060512 Name Correction: LT Afterglow detection
- GRB060512: Liverpool Telescope Afterglow detection
- GRB060507: optical afterglow detection
- GRB060425: new MASTER survey method
- GRB060502A, optical observation
- GRB 060502A: Swift/UVOT source detection
- GRB 060502B: MDM Optical Observation
- GRB 060502B: Swift detection of a short burst
- GRB060502: Super-LOTIS Observations
- GRB 060502: Swift detection of a burst with an optical counterpart
- GRB 060428B: KAIT observations
- GRB060428A: Swift/UVOT observations.
- GRB 060428: Swift detection of a burst
- GRB060424: optical afterglow detection
- GRB 060421: TTT Observations
- Konus-Wind observation of GRB 060418
- GRB060418: Optical Observations
- GRB060418: Swift XRT Team Refined Analysis
- GRB060418: Magellan/MIKE Spectroscopic Redshift
- GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
- GRB060403: optical observations
- SGR 1900+14: BAT observations
- SGR 1900+14: bright burst detected by Konus-Wind on March 28
- SGR 1900+14: Swift-BAT detection of a bright outburst
- GRB 060322: Confirmation of Swift XRT afterglow
- GRB 060211A: optical observation
- SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
- GRB 060322: Swift XRT afterglow candidate
- GRB 060323: Swift/UVOT Observations
- GRB 060323: Swift XRT refined analysis
- GRB060218/SN2006aj: optical observations
- GRB060319: Swift XRT refined analysis
- GRB060319: Swift/UVOT upper limits
- GRB060319: MASTER limit
- GRB060319: MASTER optical observation
- GRB 060313: Swift/UVOT Observations
- GRB 060313, SMARTS optical/IR observations
- GRB 060312: Swift detection of a burst
- GRB060218: analysis of the XMM-Newton observation
- GRB 060218/SN 2006aj: WIRO optical observations
- GRB 060218/SN 2006aj: RBO optical observations
- GRB 060218: Refined analysis of the radio afterglow
- GRB 060218: optical/nIR observations at La Palma
- GRB 060218A: ROTSE-III Possible Optical Flare
- Further UVOT Observations of the Candidate Optical Afterglow for GRB 060218
- GRB060218 : SDSS pre-burst observations
- GRB 060218: Swift XRT Position
- GRB 060218: Swift-BAT detection of a possible burst
- GRB 060211b: WIRO NIR Observations
- GRB 060211a: WIRO NIR Observations
- GRB 050826: Optical Afterglow and Host Galaxy
- GRB 060211A: Swift XRT Team Refined Analysis
- GRB060210:Faulkes Telescope North Afterglow Confirmation
- GRB 060210: candidate afterglow
- GRB060210: Optical afterglow
- Orphan GRB Afterglow candidate
- GRB060206: Swift XRT Refined Analysis
- GRB060206: P60 Optical Observations
- GRB060206: Swift XRT Position
- GRB 060204C: XRT analysis of Swift J061223.0+701243.9
- GRB 060203: RTT150 optical observations
- GRB 060203: P60 Confirmation of Optical Afterglow
- GRB 060202: Gemini-N J, H, K_s observations
- GRB 060202: Near-IR Observation with UKIRT/WFCAM
- GRB 060121: I-band Limits
- GRB060121: SARA Observations
- GRB 060117: PROMPT Observations
- GRB 060116: PROMPT Observations
- GRB 060115: PROMPT Observations
- GRB 060114: Swift/UVOT Observations
- GRB 060115: MITSuME optical afterglow candidate
- GRB060111A: RTT150 optical observations
- GRB 060110: Optical limit
- Swift-BAT trigger 175653 is not an astrophysical source
- Swift-BAT trigger 175653 is probably not a GRB
- GRB 051227: MDM Observation
- Swift-BAT detection of a possible burst
- GRB 051221: Improved astrometry of the IR counterpart
- GRB051211b: P60 Observations
- Possible resuming of the SGR 1806-20 activity
- GRB 051117B,optical observation
- GRB 051111: Keck HIRES redshift
- GRB051111: Swift-BAT detection of a bright burst
- GRB051109B: no UVOT source detected
- GRB 051109B: Swift detection of a burst
- GRB 051109: HET Optical Spectrum and Absorption Redshift
- GRB 051109A: ROTSE-III Decline rate for Optical Counterpart
- GRB051105B: Swift/XRT upper limit
- GRB051103: MASTER: OT limit and host galaxy candidates