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"2988 results found.
- GRB 080916: Swift detection of a burst with optical afterglow
- GRB 080915B, Swift-BAT refined analysis
- GRB 080913, Swift-BAT refined analysis
- Swift-BAT/-XRT refined analysis on trigger 324362 (LS I +61 303)
- GRB 080905B: Watcher optical detection
- GRB 080905B: Swift detection of a burst with possible optical counterpart
- GRB 080903, Swift-BAT refined analysis
- GRB 080830: Fermi Gamma-ray Burst Monitor detection
- INTEGRAL ToO observation of SGR0501+4516
- SGR 0501+4516: Decline in Activity
- SGR 0501+4516: Fermi GBM (formerly GLAST Burst Monitor) observations of three exceptionally intense outbursts
- GRB 080825B - optical counterpart candidate
- SGR 0501+4516: Swift-BAT refined analysis of the 3 discovery events
- GRB 080727C, Swift-BAT refined analysis
- GRB 080727B: Swift/UVOT Upper Limits
- GRB 080727B, Swift-BAT refined analysis
- GRB 080727: Swift detection of a burst
- GRB 080721: UVOT Follow-Up Observations
- GRB 080721 : Lulin Optical follow-ups
- GRB 080721: Swift detection of a burst with a bright optical counterpart.
- Refined analysis of Swift Trigger 316063, is IGR J08408-4503
- GRB 080613B - NOT optical and IR nondetections
- GRB 080605, Swift-BAT refined analysis
- GRB 080605, Swift-BAT refined analysis
- GRB 080605: MASTER VWF 46 s AT observation
- GRB 080605: Swift detection of a burst with an optical afterglow
- GRB 080603B, Swift-BAT refined analysis
- Swift analysis of BAT Slew Survey event (Trigger=009)
- GRB080521(?): detection of possible burst from BAT slew data and XRT ToO
- GRB 080520, Swift-BAT refined analysis
- GRB 080514B: Suzaku WAM observation of the prompt emission
- GRB 080515, Swift-BAT refined analysis
- GRB 080515: Swift detection of a burst
- GRB080506: Swift/UVOT observations
- GRB 080506, Swift-BAT refined analysis
- GRB080503, RIMOTS optical upper limit
- GRB 080506: TLS afterglow detection in VRIZ
- GRB 080506: Swift detection of a burst with optical afterglow
- GRB 080503: Swift detection of a short burst
- GRB080430: Optical observation in AsU CAS Ondrejov & Brno
- GRB 080420?: Swift detection of a possible short burst
- GRB 080413B, Swift-BAT refined analysis
- GRB 080409: Swift detection of a burst
- GRB080330: Swift XRT refined analysis
- Konus-Wind observation of GRB 080328
- GRB080330: LOAO R-band Detection
- GRB 080320: Swift XRT refined analysis
- GRB 080320: J detection with FLAMINGOS
- GRB 080320: Gemini-N optical afterglow
- GRB 080319B: Gemini-South photometry
- GRB 080320 - SDSS Pre-Burst Observations
- GRB 080319D: MASTER-VWF-Kislovodsk optical observation
- GRB 080319C: MASTER-VWF-Kislovodsk optical observation
- GRB 080319b light curve by Pi-of-the-Sky
- GRB 080319b prompt optical observation by Pi-of-the-Sky
- Swift Trigger 306616 is not a GRB
- GRB080310: Optical observation by MITSuME telescope
- GRB080229, optical upper limit
- GRB080307: Optical upper limits
- GRB 080218B, Swift-BAT refined analysis
- GRB 080218B: Swift detection of a burst
- GRB 080212, Swift-BAT refined analysis
- GRB 080210: Super-LOTIS observations
- GRB 080207, Swift-BAT refined analysis
- GRB 080207, Swift-BAT refined analysis
- GRB 080205: Swift detection of a burst
- GRB 080123: Early afterglow detection with BATSS (BAT Slew Survey)
- GRB 080123 : Suzaku WAM observation of the prompt emission
- GRB 080123: Swift detection of a short burst
- Swift-BAT refined analysis of short GRB 071227
- GRB 071227: Swift detection of a burst
- GRB 071122: MASTER optical observation
- GRB 071118: Swift detection of a burst
- Correction to the Swift-BAT Transient Identification (trigger=296683)
- GRB071112C: Errata of MITSuME Ic band photometry
- GRB071112C MITSuME Okayama Optical Observation
- GRB 071112C: Swift detection of a burst with an optical counterpart
- GRB071101: Optical and NIR upper limits by KANATA
- GRB071028: Xinglong EST V-band upper limit
- GRB071021: MARGE Optical Limits
- GRB071020, optical upper limit
- GRB071021: MITSuME Okayama Optical Upper Limits
- GRB 071018: Swift-XRT observation
- GRB 071011, Swift-BAT refined analysis
- GRB 071010B, Swift-BAT refined analysis
- GRB071008: Swift-XRT observation
- GRB 071003, Swift-BAT refined analysis
- GRB 071003: Swift detection of a bright burst
- Recent SGR1806-20 Activity
- GRB 070920B, Swift-BAT refined analysis
- GRB 070920: TAROT Calern observatory optical observations
- GRB 070911: Swift detection of a burst
- GRB070805 XRT and UVOT afterglow candidate
- GRB 070805, Swift-BAT refined analysis
- GRB 070724B: Swift-XRT afterglow confirmation
- GRB 070724B: Swift-XRT afterglow likely candidate
- GRB 070724B: Swift-XRT afterglow candidates
- Swift XRT observation of GRB 070707
- GRB 070704: Swift detection of a burst
- GRB 070628: NIR detection of afterglow