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"27478 results found.
- 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: Swift-XRT refined analysis
- GRB 080714: Enhanced Swift-XRT position
- GRB 080714: Swift detection of a burst
- GRB 080702A: optical upper limit
- GRB 080603A: CrAO optical observations
- GRB 080603B: optical observations in MAO
- GRB 080603B: optical observations in CrAO
- GRB 080710: Optical observation with MITSuME Okayama
- GRB 080710: TLS observations, steepening afterglow decay
- GRB 080702B: Swift XRT confirmation of the afterglow
- GRB 080710: Lick IR detection
- GRB 0800707: optical observations
- GRB 080710: Rapid PROMPT Observations
- GRB 080710: Swift-XRT refined analysis
- GRB080710: Swift/UVOT observations
- GRB 080710: Enhanced Swift-XRT position
- GRB 080710: Faulkes Telescope North observations
- UVOT white band observations of GRB080710
- GRB 080710: REM afterglow confirmation & brightening
- GRB 080710: KAIT OA candidate
- GRB 080710: Swift XRT position
- GRB 080710: Swift detection of a burst
- GRB 080707: possible break in the X-rays
- New Swift-XRT GRB products available online.
- GRB 080707: GROND Confirmation of the Optical Afterglow
- UVOT observations of GRB080707
- GRB 080707: Swift XRT refined analysis
- GRB 080707: Enhanced Swift-XRT position
- GRB 080707: VLT redshift
- GRB 080707: GROND Detection of the Optical Afterglow Candidate
- GRB 080707: Swift detection of a burst
- Refined analysis of Swift Trigger 316063, is IGR J08408-4503
- Trigger 316063: Swift detection of a transient
- GRB 080702B: GROND Upper Limits
- GRB 080703: Swift-XRT refined analysis
- GRB 080703: UVOT Follow-Up Observation
- GRB 080703: VLT observations of the afterglow
- GRB 080703: Enhanced Swift-XRT position
- GRB 080703: Swift detection of a burst with optical afterglow
- GRB 080703A: ROTSE-III Detection of Optical Counterpart
- No radio detection from the short GRB 080702A
- Swift/UVOT observation of GRB080702A
- GRB 080702B: Swift XRT and UVOT observations
- GRB 080702A: MITSuME Akeno optical upper limits
- GRB 080701A: Early RAPTOR optical limits
- Swift Trigger 315630: Swift/UVOT Upper Limits
- GRB 080702A: Swift-XRT Team refined analysis
- GRB 080702B : Burst detected in BAT during Swift slew
- GRB 080702A: Enhanced Swift-XRT position
- Swift Trigger 315630: Probably not a GRB
- GRB 080702: Swift detection of a short burst
- GRB 080701: Swift-XRT refined analysis
- GRB 080701A, VATT optical upper limit
- GRB 080701A: Swift/UVOT Upper Limits
- GRB 080701A: Early Super-LOTIS Observations
- GRB 080701: Enhanced Swift-XRT position
- Trigger 315630: Swift detection of a possible burst
- GRB 080701: Swift-XRT Prompt Analysis
- GRB 080701: Swift detection of a burst
- GRB 080625: Swift/UVOT Follow-Up Observations
- GRB 080625:Swift-XRT detection of the afterglow
- GRB 080625: Swift/UVOT Detection of an Optical Afterglow
- GRB 080625: Observations at OSN
- GRB 080623: GROND upper limits
- GRB080623: Swift UVOT followup observations
- GRB 080623: Swift-XRT refined analysis
- GRB 080623: Enhanced Swift-XRT position
- GRB 080623: TAROT La Silla observatory optical observations
- GRB 080623: Swift/UVOT Non-Detection of an Optical Afterglow
- GRB 080623: Swift XRT prompt analysis
- GRB 080623: Swift detection of a burst
- Swift trigger 314975 is not a GRB
- GRB080607: optical observation
- GRB 080603b: optical observation
- GRB 070809: Putative host galaxy and redshift
- VLA upper limit on INTEGRAL burst GRB 080613A
- GRB 0800603A: optical observation
- GRB080613B: MITSuME upper limits
- GRB080613A: Optical upper limits with Okayama MITSuME telescope
- GRB 080603A: optical observations on June 04
- GRB 080613A: Swift-XRT detection of the afterglow
- GRB080613A: Swift/UVOT Upper Limits
- GRB 080613A: GROND Confirmation of the Afterglow Candidate
- GRB 080613B: GROND Upper Limits
- GRB 080613B - NOT optical and IR nondetections
- GRB080613B: Swift/UVOT Upper Limits
- GRB 080613B: Swift-XRT refined analysis
- GRB 080514B: Spectroscopic constraints and probable host galaxy
- GRB 080613B: Swift detection of a burst
- GRB 080603A: Late-time Keck imaging and spectroscopy
- GRB 080603b: optical observation
- Swift observations of BAT Slew Survey event (Trigger=010)
- GRB 080603A: final Swift-XRT observations.
- GRB 080607: AGILE-MCAL observation of the prompt emission
- GRB 080603B - TLS 2nd Epoch: Another Break
- GRB 080605: TLS 3rd Epoch - Source Confusion