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"20354 results found.
- GRB 080903: Enhanced Swift-XRT position
- GRB 080903: optical observations
- GRB 080903: Liverpool Telescope observations
- GRB 080903: Optical afterglow candidate
- GRB 080903: TAROT Calern observatory optical observations
- GRB 080903: Swift detection of a burst
- SGR 0501+4516: Spin Down Rate and Inferred Dipole Magnetic Field
- SGR 0501+4516: Confirmation of the NIR counterpart
- GRB080828: Swift/UVOT Upper Limits
- SGR 0501+4516: Detection of possible optical counterpart
- GRB080825B: Swift/UVOT Upper Limits
- GRB 080828: Swift-XRT detection of a possible X-ray afterglow
- Swift-BAT trigger 322590 is not a GRB
- Swift trigger 322590: BAT detection of a possible burst
- Enhanced Swift-XRT position of SGR 0501+4516
- SGR 0501+4516: GMRT Radio Observation at 618 MHz
- GRB 080825B: Swift-XRT team analysis
- SGR 0501+4516: Fermi GBM (formerly GLAST Burst Monitor) observations of three exceptionally intense outbursts
- Suzaku ToO Observation of SGR 0501+4516
- Konus-Wind observations of new SGR 0501+4516
- SGR 0501+4516: Astrotel-Caucasus optical observations
- SGR 0501+4516: UKIRT detection of possible infra-red counterpart
- Trigger 321551: Continued Large Flaring of SGR 0501+4516
- SGR 0501+4516: optical observations
- Discovery of the Spin Period of the New Soft Gamma Repeater SGR 0501+4516
- GRB 080822: Swift detection of a short burst
- GLAST Burst Monitor detection of GRB080816
- GRB080810 - optical observations
- Radio detection of GRB 080810 with the VLA
- First GLAST Burst Monitor GRB Circulars
- GRB 080810: Swift/UVOT Refined Analysis
- GRB 080810: Liverpool Telescope observations
- GRB 080810: Kanazawa optical observation
- GRB 080810: OSN follow-up
- GRB 080810: Enhanced Swift-XRT position
- GRB 080810: KANATA optical-NIR observation, update
- GRB 080810 : optical observation with KANATA
- GRB 080810: Swift detection of a burst with a bright optical afterglow
- GRB 080723B: GROND upper limits
- GRB 080805: Faulkes Telescope South optical observations
- GRB 080804: GROND observations
- GRB 080727B: Late VLT imaging
- GRB 080805: Swift-XRT Refined Analysis
- GRB 080805: Swift/UVOT Upper Limits
- GRB 080804: Swift/UVOT Refined Analysis
- GRB 080804: Enhanced Swift-XRT position
- GRB 080804: Faulkes Telescope South observations
- GRB080805 optical limit by "Pi of the Sky"
- GRB 080805: Afterglow confirmation
- GRB 080805: GROND detection of possible afterglow
- GRB 080805: Swift detection of a burst
- GRB 080804: Swift detection of a burst with optical afterglow
- GRB 080802: Swift/UVOT Upper Limits
- GRB 080802: UVI Telescope Upper Limit
- GRB 080802: Swift detection of a probable burst
- GRB 080727B: IR photometry
- GRB 080727C: TAROT Calern observatory optical observations
- GRB 080727B: KAIT photometry and an early lightcurve break
- GRB 080727C: Swift/UVOT Upper Limits
- GRB 080727C: Liverpool Telescope observations
- GRB 080727A: VLT upper limits
- GRB 080727C: Enhanced Swift-XRT position
- GRB080727C: RTT150 optical observations
- GRB 080727C: Swift detection of a burst
- Swift detection of XTE J1701-407
- GRB 080727B: Swift/UVOT Upper Limits
- GRB080727A: Swift/UVOT Upper Limits
- GRB 080727B: Enhanced Swift-XRT position
- GRB 080727A: Enhanced Swift-XRT position
- GRB 080727B: REM prompt observations
- GRB 080727B: Swift detection of a bright burst
- GRB 080727: Swift detection of a burst
- GRB 080726: GRB Localization by SuperAGILE
- GRB 080723A: optical upper limit
- GRB080723B: Swift/UVOT Upper Limits
- GRB 080725: REM prompt observations
- GRB 080723A: Swift/UVOT Upper Limits
- VLA radio upper limit on GRB 080721
- GRB 080723, Swift-BAT refined analysis
- GRB 080723: Enhanced Swift-XRT position
- GRB 080723: Swift detection of a burst
- GRB 080721: Enhanced Swift-XRT position
- GRB 080721, Swift-BAT refined analysis
- GRB 080721: Swift detection of a burst with a bright optical counterpart.
- Trigger 317393: Swift detection of a possible GRB
- Trigger 317205: Swift detection of an outburst from XTE J1701-407
- GRB 080714: GROND confirmation of the optical/NIR afterglow
- GRB 080714: Swift/UVOT Detection of an Optical Afterglow
- GRB 080714: Enhanced Swift-XRT position
- GRB 080714: Swift-BAT refined analysis
- GRB 080714: Swift detection of a burst
- GRB 080702A: optical upper limit
- GRB 080603A: CrAO optical observations
- GRB 080710: TLS observations, steepening afterglow decay
- GRB 080702B: Swift XRT confirmation of the afterglow
- GRB 080710: Lick IR detection
- GRB 080710: Swift-XRT refined analysis
- GRB080710: Swift/UVOT observations
- GRB 080710: Enhanced Swift-XRT position
- UVOT white band observations of GRB080710