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"27293 results found.
- GRB060512: Liverpool Telescope Afterglow detection
- GRB 060512: Swift detection of a burst with an optical afterglow
- GRB 060510A: Swift/UVOT Detection of an Optical Afterglow
- GRB 060505: X-ray afterglow - Correction -
- GRB 060505: X-ray afterglow
- Konus-Wind observation of GRB 060510A
- GRB 060428a, SMARTS optical/IR afterglow detection
- GRB060510B: Swift XRT refined analysis
- GRB 060510B: Swift/UVOT Upper Limits
- GRB 060510A: Refined analysis of the Swift-BAT burst
- GRB 060510B: Swift-BAT Refined Analysis
- GRB060510A: XRT refined analysis
- GRB060510B : Faulkes North Telescope detection
- GRB 060510B: Super-LOTIS Observations
- GRB 060510B: MDM Observations and candidate OT
- GRB 060510B: Swift detection of a burst
- GRB 060510: Swift detection of a burst with optical transient
- GRB060507: optical afterglow detection
- GRB060502B: improvement in the XRT afterglow position
- GRB 060507: BART limit
- GRB 060507: Final Refined analysis of the Swift-BAT burst
- GRB 060507: Swift-BAT Refined Analysis
- GRB 060507: Swift/UVOT Upper Limits
- GRB 060507: Swift XRT Team Refined Analysis
- GRB 060507: MDM Optical Upper Limit
- GRB060507: Swift XRT position
- GRB 060507: Swift detection of a burst
- GRB060505: Swift/UVOT Observations
- GRB 060505: Swift XRT Team Refined Analysis
- GRB 060505: Swift XRT afterglow canditate position
- GRB 060505: Swift-BAT detection of a weak burst
- GRB 060502B MDM Follow-up Observation
- GRB060502A, optical observation
- GRB 060502B: Swift/UVOT upper limits
- GRB 060502A: Swift/UVOT source detection
- GRB 060502B: MDM Optical Observation
- GRB 060502B: Refined analysis of the Swift-BAT short burst
- GRB060502B: Swift XRT Team refined analysis
- GRB060502B: correction to XRT position
- GRB 060502B: MASTER optical observations
- GRB 060502B: Swift detection of a short burst
- GRB060502: Swift-XRT refined analysis
- GRB 060502: Swift-BAT refined analysis
- GRB 060502: APO Spectroscopic Observations
- GRB060501: Swift UVOT followup observations
- GRB060502: Super-LOTIS Observations
- GRB 060502: Swift detection of a burst with an optical counterpart
- GRB 060501: MDM Observations
- GRB060501: Super-LOTIS observations
- GRB060501: P60 imaging and afterglow candidate
- GRB 060501: Refined analysis of the Swift-BAT burst
- GRB060501: Swift XRT position
- GRB 060501: ROTSE-III Optical Limits
- GRB 060501: Swift detection of a burst
- GRB060428B: optical observation
- GRB060428B: possible detection of an optical counterpart by Swift/UVOT.
- GRB 060428B: MDM Observations
- GRB060428B: Swift XRT Team refined analysis
- GRB 060427B: IPN localization of a short hard burst
- GRB 060428B: Refined analysis of the Swift-BAT burst
- GRB 060428B: KAIT observations
- GRB 051117A: Bright host galaxy not confirmed
- GRB060428A: Swift/UVOT observations.
- GRB060428B, optical observation
- GRB 060428A: Refined analysis of the Swift-BAT burst
- GRB060428A: Swift XRT Team refined analysis
- GRB 060428B: Swift detection of a burst
- GRB 060428: Swift detection of a burst
- GRB 060427: NOT observations
- GRB 060427: Swift/UVOT upper limits.
- GRB 060427: Refined analysis of the Swift-BAT burst
- GRB060427: Swift XRT Team refined analysis
- GRB060418: Swift XRT Team Further Refined Analysis
- GRB 060427, optical observation
- GRB 060427: Swift detection of a burst
- GRB 060425: IPN localization and KW spectrum of a short, hard burst
- GRB060424: optical afterglow detection
- GRB060418: Further Analysis of MIKE Spectroscopy
- GRB 060424: Refined analysis of the Swift-BAT burst
- GRB 060424: Swift detection of a burst
- OT 060420: Likely Not a New Cosmic Transient
- Swift-BAT detection of Mrk 421
- OT 060420: CONCAM detection of a candidate new magnitude 5 optical
- GRB060421: Swift/UVOT observations
- GRB 060421: Swift-BAT Refined Analysis
- GRB 060421: Swift-XRT refined analysis
- GRB 060418: prediction of t_break
- Konus-Wind observation of GRB 060418
- GRB(?)060421:MASTER optical limit
- GRB(?)060421 : XRT position
- Possible GRB060421: BART limits
- GRB(?) 060421: Swift detection of a burst
- GRB 060418: Radio Observations
- GRB060418: Swift/UVOT Observations
- GRB 060418: FRAM early afterglow observation
- GRB 060418: Refined Analysis of the Swift-BAT burst
- VLT/UVES observations of GRB060418
- GRB060418: Swift XRT Team Refined Analysis
- GRB060418: Magellan/MIKE Spectroscopic Redshift
- GRB060418 : LT optical afterglow observation