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"19570 results found.
- GRB060428A: Swift/UVOT observations.
- GRB060428B, optical observation
- GRB 060428A: Refined analysis of the Swift-BAT burst
- GRB 060428b : Kiso R-band limit
- GRB 060428b: Optical afterglow candidate
- GRB 060428B: Swift detection of a burst
- GRB 060427: NIR observations
- GRB060427: Xinglong optical Observations
- GRB 060428: Swift detection of a burst
- GRB 060427: Swift/UVOT upper limits.
- GRB 060427, optical observation
- GRB 060427: Swift detection of a burst
- GRB 060424: Refined analysis of the Swift-BAT burst
- GRB060421: Swift/UVOT observations
- GRB(?) 060421: Swift detection of a burst
- Erratum of GCN 4983 for GRB 060418 IR follow-up
- GRB 060418 : IR afterglow observations
- GRB 060418: Radio Observations
- GRB060418, BVRcIc field calibration
- GRB060418: Swift/UVOT Observations
- GRB 060418: Refined Analysis of the Swift-BAT burst
- GRB060418 : LT optical afterglow observation
- GRB 060418: REM candidate afterglow
- GRB 060418: Swift detection of a burst with bright x-ray and optical afterglow
- SGR 1900+14: Refined analysis of the Swift-BAT outburst
- GRB060413: Swift/UVOT upper limits
- GRB 060413: REM NIR Observations
- SGR 1900+14: Swift detection of an outburst
- GRB 060413: Swift detection of a burst
- GRB 060403: MITSuME optical observation
- GRB060403: Optical Limit
- GRB 060403: Swift/UVOT upper limits
- SGR 1900+14: BAT observations
- GRB 060403: Refined analysis of the Swift-BAT burst
- GRB 060403: Swift detection of a burst
- HETE trigger H4044: RTT150 optical observations
- GRB060331: Swift/UVOT upper limits
- Swift XRT observations of the HETE transient H4043
- H4043, an unusual high-energy transient observed by HETE
- GRB 060322: LNA optical limit
- SGR 1900+14: Swift-BAT detection of a cluster of outbursts
- GRB 060323 : WIDGET simultaneous optical observations
- GRB 060323: Early optical observation at Xinglong
- GRB 060322: Confirmation of Swift XRT afterglow
- GRB060323: NOT optical observations
- GRB 060322: IAC80 optical observations
- GRB 060322: Swift XRT afterglow candidate
- GRB060323: P60 Observations
- GRB 060323: Swift/UVOT Observations
- GRB 060323: optical afterglow confirmed
- GRB060323: NOT observations
- GRB 060323: Optical Observations
- GRB 060323: optical observations at TNG
- GRB 060323: BVRI observations at Tautenburg, aftreglow candidate
- GRB060323, optical observation
- GRB060323 - SDSS Pre-Burst Observations
- GRB 060323: Swift detection of a burst with a possible optical afterglow
- GRB 060322: Swift-BAT detection of a 200-sec burst
- GRB 060218/SN 2006aj, LNA optical observation
- GRB060218: Refined photometric calibration of comparison stars
- GRB 060319: WHT K-band candidate afterglow
- GRB060319: Swift/UVOT upper limits
- GRB060319: MASTER limit
- GRB 060319 optical observations at TNG
- GRB060319 : Liverpool Telescope optical limit
- GRB060319 - SDSS Pre-burst Observations
- GRB 060319: Swift detection of a burst
- GRB060313: Radio Observations
- GRB 060313: early afterglow NIR upper limits with REM
- GRB 060313: Swift/UVOT Observations
- GRB 060313: Swift XRT position
- GRB 060313, SMARTS optical/IR observations
- GRB060313: optical and near infrared observations with REM
- GRB 060313: Swift-BAT detection of a bright short hard burst
- GRB060218: SARA Observations of SN2006aj
- GRB 060312: Swift XRT team refined analysis
- GRB060306: APO Ks-band Imaging Observations
- GRB 060312: ROTSE-III Optical Limits
- Bright short hard GRB 060303: IPN localization and Konus spectrum
- GRB 060306: MAGNUM observations
- GRB060218: analysis of the XMM-Newton observation
- Swift/UVOT observations of GRB060306
- GRB 060306: Swift-XRT team refined analysis
- GRB 060306: Swift detection of a bright burst
- GRB060218: Ep,i - Eiso correlation
- GRB060223b: optical limit
- GRB 060223b: Swift/UVOT Upper Limits
- GRB 060218/SN 2006aj: K-380 optical observations
- GRB 060218/SN 2006aj, SMARTS optical/IR observations
- GRB 060223B: Swift XRT possible afterglow
- GRB 060218/SN 2006aj: REM optical and near-infrared observations
- GRB 060218 : Radio upper limits from GMRT
- GRB 060223A:Xinglong optical limits
- GRB 060223B: Swift-BAT refined analysis
- GRB 060223a: Swift/UVOT refined analysis
- GRB 060218/SN 2006aj: Swift-BAT fluence and peak flux
- GRB 060223B: Swift detection of a bright burst
- GRB 060218: rebrightening
- Spectral properties of GRB060218/SN2006aj
- GRB 060218: Decline in r-band flux