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"
3821 results found.
- Radio Detection of SGR 0501+4516
- SGR 0501+4516: MDM Optical Observations
- SGR 0501+4516: Astrotel-Caucasus optical observations
- SGR 0501+4516: UKIRT detection of possible infra-red counterpart
- SGR 0501+4516: WSRT Radio Observations
- Trigger 321551: Continued Large Flaring of SGR 0501+4516
- SGR 0501+4516: optical observations
- Swift Trigger 321481: A Large Flare from SGR 0501+4516
- SGR 0501+4516: Swift-BAT refined analysis of the 3 discovery events
- Discovery of the Spin Period of the New Soft Gamma Repeater SGR 0501+4516
- Third event from SGR 0501+4516
- GRB 080822 (SGR 0501+4516): archival optical observations
- New Soft Gamma Repeater 0501+4516 was GRB 080822
- GRB 080727B: Late VLT imaging
- Trigger 317393: Swift detection of a possible GRB
- Trigger 317205: Swift detection of an outburst from XTE J1701-407
- GRB 080710, Swift-BAT refined analysis
- GRB 080710: Swift detection of a burst
- GRB 080707: Swift detection of a burst
- GRB 080702B : Burst detected in BAT during Swift slew
- GRB 080701: Swift detection of a burst
- GRB 080613B: Swift detection of a burst
- GRB 080604: Swift detection of a burst with an optical afterglow
- SGR 1627-41: Chandra/RXTE/Swift Observations Scheduled
- Konus-Wind observation of reactivation of SGR 1627-41
- Reactivation of SGR 1627-41
- GRB 080515: KPNO 4m NIR afterglow detection
- GRB 080506: NAYUTA Optical Observation
- GRB080430: Optical observation in AsU CAS Ondrejov & Brno
- GRB 080426: Swift detection of a possibly short burst
- GRB 080413A: MOA-II optical afterglow observations
- GRB 080330, SMARTS optical/IR afterglow observations
- GRB 080319A: UVOT Observations
- GRB 080319C: Swift-XRT Team Refined Analysis
- GRB 080319C: Swift detection of a burst with an optical afterglow
- GRB080310: Super-LOTIS suggestion of brightening
- GRB080307, optical upper limit
- GRB 080307: retraction of UVOT candidate
- GRB 080303A: ROTSE-III Optical Limits
- GRB080229: Possible optical afterglow
- UVOT analysis for GRB080229
- GRB 080218: Swift detection of a burst
- GRB 080207, Swift-BAT refined analysis
- GRB 080207, Swift-BAT refined analysis
- GRB 080129: Swift-XRT refined analysis
- GRB 080129: Gemini-South Imaging Observations
- Konus-Wind observation of GRB 080122
- GRB 080121: Swift-BAT detection of a very weak, short burst
- IPN triangulation of very bright GRB 071125
- Disregard the "GRB 071126" position
- GRB 071118: Swift detection of a burst
- GRB 071101: Swift detection of a burst
- GRB 071028: Swift-XRT Team refined analysis
- GRB 071028: Swift detection of a burst
- GRB071020, optical upper limit
- GRB 071017: a SHORT GRB detected by INTEGRAL
- GRB071010B: Swift/XRT detection
- GRB 070911, SMARTS optical/IR afterglow observations
- GRB 070920B: ROTSE-III Early Optical Limits
- INTEGRAL ToO observations of SGR1806-20
- GRB 070920b, SMARTS optical observation
- SGR1806-20: Swift-BAT detection of enhanced activity
- GRB 070911: Swift XRT refined analysis
- GRB 070911, Swift-BAT refined analysis
- Intense burst from SGR 1806-20 detected on September 7
- GRB 070810: ROTSE-III Detection of Optical Counterpart
- GRB 070809: ROTSE-III Optical Limits
- GRB 070808: Xinglong TNT optical Upper Limit
- GRB070808: Optical observations with KANATA
- GRB 070808: Swift detection of a burst
- Swift detection of a outburst from SAX J1810.8-2609
- VLA non-detection of GRB 070721B
- AGILE-ACS position for the SGR 1806-20 July 27 burst
- Intense burst from SGR 1806-20 detected on July 27
- GRB 070326: Detection of first burst from BAT Slew Survey (BATSS)
- GRB 070714: Swift detection of a bright burst, possibly short
- GRB 070628: Watcher Observations
- OT20050728 was not an optical GRB afterglow
- GRB 070616: Swift detection of a burst
- GRB 070612A: P60 Confirmation of Afterglow and An Underlying, Nearby
- GRB 070611: Swift/UVOT Observations
- GRB 070611: ROTSE-III Detection of Late Rising Optical Counterpart
- GRB 070611; Swift-XRT position
- Swift trigger 280447 is probably a Galactic transient
- GRB 070518: MARGE Observations
- GRB070521: P200 Observations
- GRB 070508: Suzaku/WAM observation of the prompt emission
- GRB 070507: Swift detection of a possible cosmic ray shower event or a possible burst
- GRB070429B: VLT observations
- GRB070429B: possible host galaxy detection
- Konus-Wind observation of GRB 070420
- GRB 070420 Swift-BAT Refined Analysis
- Suzaku ToO observation of SGR 1806-20
- INTEGRAL ToO Observation of SGR1806-20
- long burst from SGR 1806-20 detected on March 26
- Short-Hard GRB 070209: PROMPT Observations
- GRB 070318: Swift detection of a burst with an optical afterglow
- GRB 070224: SARA upper limit
- GRB 070224: MASTER-Net refind analysis
- GRB 070224: MASTER-VWF-Kislovodsk observations