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"5819 results found.
- GRB 071001: Swift-XRT Team refined analysis
- GRB 071001: Swift detection of a burst
- GRB 070911, SMARTS optical/IR afterglow observations
- GRB 070925: Gemini South Imaging
- Recent SGR1806-20 Activity
- GRB 070917: Suzaku/WAM observation of the prompt emission
- INTEGRAL ToO observations of SGR1806-20
- GRB 070920b, SMARTS optical observation
- GRB 070920: TAROT Calern observatory optical observations
- GRB070917: optical observations
- GRB 070917: MITSuME Akeno Ic upper limit
- GRB 070911: Suzaku WAM observation of the prompt emission
- GRB 070913: Swift-XRT detection of the possible X-ray afterglow
- GRB 070913: SMARTS optical/IR observations
- GRB 070913: TAROT La Silla observatory optical observations
- Intense burst from SGR 1806-20 detected on September 7
- GRB 070824 - Combined SuperAGILE/IPN Localization
- GRB 070731: Swift/UVOT Upper Limit
- GRB 070809: Swift/UVOT Upper Limits
- GRB 070809: Keck Imaging
- GRB070808 - SDSS Pre-Burst Observations
- GRB 070808: Swift detection of a burst
- Swift trigger on 4U 1700-377 while star tracker loss-of-lock
- Swift detection of a outburst from SAX J1810.8-2609
- GRB 070724B: Swift-XRT afterglow confirmation
- GRB070802: Swift/UVOT upper limits
- GRB 070802: Confirmation of the optical afterglow
- GRB 070802: Swift detection of a burst
- GRB 070724B: Swift-XRT afterglow likely candidate
- GRB 070724B: Suzaku WAM observation of the prompt emission
- GRB 070724B: Swift-XRT afterglow candidates
- GRB 070724b: First Gamma Ray Burst Localization by SuperAGILE onboard
- GRB 070721B: Swift detection of a burst
- GRB 070714: Swift detection of a bright burst, possibly short
- GRB070621: Swift XRT refined analysis
- GRB 070621: Gemini South optical imaging
- GRB 070621: Swift detection of a burst
- GRB 070616: Swift detection of a burst
- SWIFT J195509.6+261406 (GRB 070610): further observations
- GRB 070612B: KAIT limits
- GRB 070610: OPTIMA-Burst detection of continued strong flaring activity
- GRB 070611: VLT redshift
- Swift trigger 280447 is probably a Galactic transient
- GRB 070520B: Swift detection of a burst
- GRB 070520: Swift detection of a burst
- GRB 070508: Swift detection of an intense burst with an optical counterpart
- GRB070429B: VLT observations
- GRB 070429B: ROTSE-III Optical Limits
- GRB 070429B: Swift detection of a short burst
- GRB 070429: Swift detection of a burst
- GRB 070411: Late-time Keck imaging
- GRB 070411 : Planned XMM-Newton observation
- GRB 070411, deep LBT photometry
- GRB 070419A: RAPTOR Detection of Early Emission
- GRB 070419: Swift detection of a burst
- GRB 070318, SMARTS optical/IR afterglow observations
- GRB 070411: TLS data shows plateau, flares
- GRB 070411: Swift/UVOT observations
- GRB 070412: further NOT observations
- GRB 070411: Magellan/Clay photometry
- GRB 070411: Magellan/IMACS photometry
- GRB 070412: Nearby bright galaxy
- GRB 070411: Optical observations at Crni Vrh
- GRB 070411: Swift detection of a burst with optical afterglow
- GRB 070328: Swift detection of a burst
- Short-Hard GRB 070209: PROMPT Observations
- GRB 070318: Swift detection of a burst with an optical afterglow
- GRB 070306: IR observations and candidate afterglow
- GRB 070306: XRT Team Refined Analysis
- GRB070306 - SDSS Pre-burst Observations
- GRB 070227: optical observations
- GRB 070227: optical observations
- GRB070223: Swift burst
- GRB 070220: ART-3 Optical and NIR limits
- GRB 070220: Swift detection of a burst
- GRB 070208: MARGE Optical Observations
- GRB 070208: RAPTOR detection of early afterglow onset
- GRB 070208: MDM Optical Decay
- GRB 070208: Early IR detection and afterglow astrometry
- GRB 070208: Afterglow confirmation from P60
- GRB 070208: ROTSE-III Optical Limits
- GRB 070208: MDM Observations
- GRB 070208: Swift detection of a burst
- GRB 070125: optical observation
- GRB 070125: An IR Point Source and an Apparent Host Galaxy
- GRB 070129: Swift detection of a burst
- GRB 070125: further AAVSO optical observations
- GRB 070125: AAVSO optical observations
- GRB 070125: Continued P60 Observations
- GRB070125: Swift-XRT Refined Analysis
- GRB 070125: P60 Optical Afterglow Candidate
- GRB 070110: Swift detection of a burst with a possible optical afterglow
- GRB 061201: Nearby Galaxy Cluster Abell 995 is at z=0.0865
- Retractions of previous Swift-BAT triggers
- GRB 061210: Swift/XRT Astrometry Correction
- GRB 061222A: MITSuME Akeno optical upper limits
- GRB 061222B: Swift detection of a burst
- GRB 061201: Correction to GCN 5944
- GRB 061201: Magellan Redshift of nearby Abell cluster
- GRB 061210: MDM Follow-up Observation