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"3999 results found.
- GRB061019: optical observations
- GRB 061019: SMARTS afterglow confirmation
- GRB 061019: REM K-band candidate afterglow
- GRB061019: Swift/XRT position
- GRB 061007: Suzaku/WAM observation of the prompt emission
- GRB 061007: Swift-BAT refined analysis
- GRB 061007: Swift detection of a burst with an optical counterpart
- GRB 061002: Swift detection of a burst: CORRECTED CONTENT
- GRB 061002: Swift detection of a burst
- GRB 060929: TNG K-band observations
- GRB060929: Optical limit
- GRB 060729: An update on the late-time Swift observations
- GRB 060923A: Schedule of Spitzer Space Telescope Observations
- GRB 060926: Swift detection of a burst
- GRB 060923C: Keck Observations
- Swift detects a hard X-ray burst from AXP CXOU J164710.2-455216
- GRB 060919, Swift-BAT refined analysis
- GRB060904b optical detections (delayed report due to internet outage)
- GRB 060904B: RTT150 optical observations
- Two bright bursts from SGR 1806-20 detected with IBAS
- GRB 060825: VLA observations
- GRB060729: analysis of XMM-Newton observation
- GRB 060813: Swift XRT refined analysis
- Image of the dust-scattering halo around SGR 1806-20
- Second VLA limit on new radio point source in SGR 1806-20
- A dust-scattering halo detected around SGR 1806-20
- GRB060714: optical observations
- GRB060807: Optical limiting magnitudes
- VLA Upper Limit on Outburst of SGR 1806-20
- GRB060806 is similar to previous activity of SGR1806-20
- GRB 060728: Upper limits of the X-ray emission
- GRB 060729: Swift/UVOT Detections
- GRB 060729: Swift/UVOT Observations
- GRB 060729: Swift detection of a burst with an UVOT optical counterpart
- GRB 060728, SMARTS optical/IR observations
- GRB060614 ATCA Radio Limits
- GRB060526: optical observations
- GRB 060515: Upper Limit on Host Galaxy
- GRB050124: Possible Host Galaxy
- GRB 060614: Swift/UVOT Observations
- BAT Trigger #214277 is SGR 1900+14
- GCN 060607: Swift-UVOT obswervations.
- GRB 060607: REM NIR afterglow
- GRB 060607: Swift detection of a burst with bright optical counterpart
- GRB 060522: PROMPT Optical Limits
- GRB 060604A: ROTSE-III Optical Limits
- GRB 060526: RTT150 optical observations
- GRB 060526: RTT150 optical observations
- GRB 060526: Watcher Observations
- GRB 060526: Swift detection of a burst with x-ray and optical afterglow
- GRB 060515: Swift/XRT Team refined analysis
- GRB 060515: Swift/XRT position
- GRB 060515: TAROT optical observation
- GRB 060515: ROTSE-III Optical Limits
- GRB 060428a, SMARTS optical/IR afterglow detection
- GRB060418: Swift XRT Team Further Refined Analysis
- GRB060424: optical afterglow detection
- GRB 060421: TTT Observations
- SGR 1900+14: Refined analysis of the Swift-BAT outburst
- SGR 1900+14: Swift detection of an outburst
- SGR 1900+14: BAT observations
- Konus-Wind observation of the recent SGR 1900+14 activity. Will
- GRB060331: Swift/UVOT upper limits
- SGR 1900+14: bright burst detected by Konus-Wind on March 28
- SGR 1900+14: Swift-BAT detection of a cluster of outbursts
- SGR 1900+14: Swift-BAT detection of a bright outburst
- SGR 1900+14: CORRECTION to GCN 4923
- SGR 1900+14: Refined Swift-BAT analysis of the renewed activity
- SGR 1900+14: Swift detection of renewed activity
- GRB 060223B: Swift XRT possible afterglow
- GRB 060218: rebrightening
- GRB 060218: Likely an underluminous GRB
- GRB 060211A: Further refined analysis of the Swift burst
- GRB 060211A: Partial refined analysis on the Swift-BAT burst
- GRB 060211B: Swift/BAT refined analysis
- GRB 060211A: Swift XRT Team Refined Analysis
- GRB 060211: Swift detection of a long burst
- GRB060206: Swift-BAT detection of a burst
- GRB 060202: Gemini-N J, H, K_s observations
- GRB 051211A: MDM Observations
- GRB060130: REM infrared observations
- GRB 060116: MARGE optical observations
- GRB060121: SARA Observations
- GRB 060121: optical observations
- GRB 060114: Swift/UVOT Observations
- GRB 060111B: Refined analysis of the Swift-BAT burst
- GRB 060111B: ROTSE-III Detection of Optical Counterpart Flare
- GRB 051221: Swift/UVOT upper limits
- GRB 051211B: Swift XRT confirmation of the afterglow
- An extraordinary long burst on December 3 from SGR1806-20
- Possible resuming of the SGR 1806-20 activity
- GRB 051117A: Refined analysis of the Swift-BAT burst
- GRB050925: analysis of the XMM-Newton observation
- GRB/SGR 050925: XMM-Newton ToO observation
- GRB 051111a: IR photometry
- GRB 051008 Tautenburg Supernova Search
- GRB 051109: Rc and Ic observations
- GRB051103: MASTER: OT limit and host galaxy candidates
- IPN triangulation and Konus spectrum of the bright short/hard GRB051103
- GRB 051105b: ART optical limits