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"
2724 results found.
- GRB 150210A: MASTER SN detection during LAT error box inspection
- GRB 150204A: GROND observations
- GRB 150203A iTelescope observation
- GRB 150204A: LCOGT-Sutherland and Siding Springs observations
- GRB 150202B: Swift XRT/UVOT observations
- GRB 150201A: GROND upper limits
- Konus-Wind observation of GRB 150127B
- GRB 150123A: MASTER inspection
- Swift Trigger 628458 likely not astrophysical
- Konus-Wind observation of GRB 150118B
- GRB 150120B: P60 optical afterglow
- Swift detection of 4U 1700+24 (= V* V934 Her)
- GRB 141229A: MAXI/GSC detection
- GRB 141225A: MASTER-SAAO first OT detection
- GRB 141225A: Enhanced Swift-XRT position
- GRB 141225A: UVOT detection
- GRB 141225A: Optical aftergow confirmation
- GRB 141225A: LT optical candidate
- GRB 141225A: 1.23m CAHA optical observations
- GRB 141225A: Swift detection of a burst
- IPN Triangulation of GRB 141222A (very intense)
- GRB 141220A: Fermi GBM observation
- Swift detection of 4U 1700+24 (= V934 Her)
- GRB 141212A: MASTER early optical observations
- GRB 141130A: Swift/UVOT Detection
- GRB 141130A: Swift detection of a burst with an optical counterpart
- GRB 141121A: MITSuME Akeno Optical observation
- GRB 141121A: MAXI/GSC detection
- GRB 141109A: Swift-BAT refined analysis
- GRB 141109A: CQUEAN Detection at 0.85 - 1.05 micron
- GRB 141109B: Swift detection of a burst
- GRB 141104A: Swift-XRT observations
- GRB 141028A: TShAO optical observation
- GRB 141031B: Nanshan optical upper limit
- Konus-Wind observation of GRB 141017A
- Swift detection of outburst from 4U 1700+24
- GRB 140916B: iPTF Optical Observations
- GRB 140916A: Swift detection of a burst
- Fermi GBM trigger 140913075 is not a GRB
- GRB 140907A: T100 observations
- GRB 140906B: Fermi GBM Detection of a Long GRB
- IPN triangulation of GRB 140810A
- Konus-Wind observation of GRB 140810A
- Swift trigger 609139 is probably 4U 1850-03
- GRB 140723A: MASTER optical observation
- IPN Triangulation of GRB 140721A
- GRB 140716A: GROND confirmation of the afterglow
- GRB 140713A : Xinglong TNT upper limit
- GRB 140703A: MASTER optical observations
- GRB 140703A: BOOTES-2 and OSN optical observations
- Fermi 425667201: optical counterpart search
- GRB 140629A: KWFC z-band photometry
- GRB 140628A: Swift-XRT refined Analysis
- GRB 140620A / iPTF14cva: TShAO optical observations
- GRB 140620A: Swift/UVOT Detection
- GRB 140619B: Fermi-LAT Detection
- GRB 140614B: MITSuME Akeno upper limits
- Fermi 423717114: Additional P48 and P60 observations
- Konus-Wind observation of GRB 140528A
- IPN Triangulation of GRB 140528A
- Swift detection of SFXT IGR J17544-2619
- Swift trigger 599860 probably not real
- GRB 140515B: MAXI/GSC detection
- GRB 140515A: MITSuME Akeno upper limits
- Konus-Wind observation of GRB 140508A
- GRB 140508A: SAO RAS and MASTER photometric and spectroscopic observations
- GRB 140502A: MITSuME Okayama upper limits
- GRB 140419A: MITSuME Okayama Optical Observation
- Swift Trigger 595345 is not an astrophysical source
- GRB 140408A: MITSuME Okayama upper limits
- IPN Triangulation of GRB 140329A
- GRB 140320D: Suzaku WAM observation of the prompt emission
- GRB 140320A: Enhanced Swift-XRT position
- GRB 140320A: Swift-XRT detection of an afterglow candidate
- GRB 140320B: Xinglong TNT upper limit
- GRB 140311C: MASTER before, during and after trigger optical observations
- IPN Triangulation of GRB 140306A
- GRB 140219A: Suzaku WAM observation of the prompt emission
- GRB 140219A: MASTER before and after GRB observational arguments of the exceptionally Dark GRB
- GRB 140221A: MAXI/GSC detection
- GRB 140215A: Swift/UVOT Detection
- GRB 140215A: Swift-BAT refined analysis
- GRB 140215A: ISON-NM optical observations
- GRB 140215A: T24 optical observations
- GRB 140215A: Enhanced Swift-XRT position
- GRB 140215A: Swift detection of a burst with optical counterpart
- GRB 140209A: optical observations
- GRB 140129B: Swift/UVOT Detection
- GRB 140129B: MASTER OT early light curve
- GRB 140129B: Swift detection of a burst with an optical afterglow
- Fermi412093190: iPTF optical counterpart search
- GRB 140103A: AAO optical afterglow candidate
- GRB 140108A: MASTER-Net OT detection
- GRB 140105A/Fermi410578384: MASTER-Net early optical observations
- GRB140104A : Xinglong TNT observation. A bright star is located nearby
- GRB 140102A: Fermi/GBM Observation
- GRB 140102A: MAXI/GSC detection
- GRB 140102A: Swift-XRT refined Analysis
- GRB 140102A: Fermi-LAT detection of a burst
- Konus-Wind observation of GRB 131226A