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"23404 results found.
- GRB080307 - SDSS Pre-Burst Observations
- GRB 080307: TNT optical observation
- GRB080307: Optical upper limits
- GRB 080307: Gemini-N i-band observations - candidate afterglow
- GRB 080307: BOAO imaging - retraction and new limit
- GRB 080307: Enhanced Swift-XRT position
- GRB 080307, Preliminary Swift-BAT refined analysis
- GRB 080307: Optical observation with DMC/KANATA
- GRB 080307: Swift detection of a burst
- VLA possible radio detection of GRB 080229
- GRB 080303: Swift/UVOT follow-up of afterglow detection
- GRB 080303: Enhanced Swift-XRT position
- Swift UVOT observations of GRB080229B
- GRB080229B: Swift XRT afterglow observation
- GRB 080303: Swift detection of a burst with optical afterglow
- GRB 080303: REM NIR afterglow candidate
- GRB 080303A: ROTSE-III Optical Limits
- GRB 080229: I-band observations from OSN
- GRB 080229: VLT NIR observations
- GRB 080229: TNG NIR observations
- GRB 080229: Deep Gemini/GMOS optical observations
- GRB 080229: Enhanced Swift-XRT position
- GRB 080229: REM NIR observations
- GRB080229: Possible optical afterglow
- GRB 080229B: Gamma Ray Burst Localization by SuperAGILE
- UVOT analysis for GRB080229
- GRB 080229, Swift-BAT refined analysis
- GRB 080229A: ROTSE-III Optical Limits
- GRB 080229: Swift detection of a bright burst
- XRF 080109/SN2008D : GMRT upper limit at 1.28 GHz
- GRB 071010B : Early optical brightening detected by TAOS
- Swift-XRT improved positions, and new redshift limits.
- GRB 080218B, Swift-BAT refined analysis
- GRB 080218B: Swift-XRT refined analysis
- Swift/UVOT observations of GRB080218B
- GRB 080218B: REM NIR early upper limits
- GRB 080218B: Enhanced Swift-XRT position
- GRB 080218B: GROND upper limits
- GRB 080218B: Swift detection of a burst
- GRB 080218: Swift detection of a burst
- Swift-XRT and UVOT observations of the IPN burst GRB 080211
- VLA radio upper limit on GRB 080212
- Swift/UVOT refined analysis of GRB080212
- GRB080212: Optical afterglow candidate observed by MITSuME Telescope
- GRB 080212: GROND detects afterglow
- GRB 080212: REM NIR afterglow?
- GRB 080212: Enhanced Swift-XRT position
- GRB 080210: Keck photometry
- VLA non-detection of GRB 080210
- GRB 080212: Swift detection of a burst
- IPN localization of GRB 080211
- GRB 080207: VLT NIR early upper limits
- GRB 080210: Swift/UVOT Refined Analysis
- GRB 080210, Swift-BAT refined analysis
- GRB 080210: Super-LOTIS observations
- GRB 080210: Enhanced Swift-XRT position
- GRB 080210: GOND detection in all bands and redshift upper limit
- GRB080210 - SDSS Pre-Burst Observations
- GRB 080210: Swift detection of a burst with optical afterglow
- GRB 080210: TAROT La Silla observatory optical detection
- GRB 080207: GROND upper limits
- GRB 080205: GAO 150cm telescope Optical limit
- GRB 080207: Optical limits from Gemini-South
- Swift detection of AX J1749.1-2639
- GRB 080207: Super-LOTIS observations
- GRB080207: RTT150 Optical Observations
- GRB 080207: REM NIR observations
- GRB080207: Swift/UVOT refined analysis
- GRB 080207: TAROT Calern observatory optical observations
- GRB 080207: Swift-XRT Refined Analysis
- GRB 080207: Enhanced Swift-XRT position
- GRB 080207: Swift detection of a burst
- GRB 080205 optical upper limit
- GRB 080205: optical observation
- VLA radio upper limit on GRB 080205
- INT+WFC R-band observations of GRB 080205
- GRB 080205, Swift-BAT refined analysis
- IPN localization of very hard GRB 080204
- GRB 080205: Swift/UVOT observations
- GRB 080205: Enhanced Swift-XRT position
- GRB 080205: Swift detection of a burst
- Swift-BAT Trigger #302454, correction of GCN notice, update on AX J1749.1-2639
- GRB 080130: Swift-BAT refined analysis
- GRB 080130: further Swift XRT observations confirm fading source
- GRB 080129: Swift/UVOT Refined Upper Limits
- Swift/UVOT observations of GRB080130
- GRB 080130: REM NIR observations
- GRB 080130(?): Swift XRT observation
- GRB 080129: Swift-XRT refined analysis
- GRB 080129: KAIT optical limits
- GRB 080129: TAROT La Silla observatory optical observations
- GRB 080129: GROND detection in all bands, and fading
- GRB 080129: GROND detection of the optical/NIR afterglow, and fading
- GRB 080129: Enhanced Swift-XRT position
- GRB 080129: Gemini-South Imaging Observations
- GRB 080129 (?): UVOT Upper Limits
- GRB 080129 (?): Swift detection of a possible burst
- GRB 080121: Upper limit on X-ray afterglow
- GRB 080121: Swift/UVOT upper limits
- SNe 2008D and 2007uy: Chandra Detections