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"7297 results found.
- GRB 130816A: Swift detection of a burst
- GRB 130812A: Swift detection of a burst
- GRB 130807A: Swift detection of a GRB or Galactic transient
- GRB 130806A: Swift detection of a burst
- Trigger 565443: Swift detection of a burst from SGR J1745-29
- GRB 130803A: Faulkes Telescope South Observations
- GRB 130803A: Swift detection of a burst
- GRB 130722A: RATIR Optical Observations
- GRB 130727A: Swift-XRT and Swift-UVOT prompt observations
- GRB 130725A: MITSuME Ishigakijima Optical Observation
- GRB 130719A: Skynet/PROMPT observations
- Swift Trigger 563980 is GRB 130725A
- GRB 130722C Tiled Swift observations
- GRB 130722A: Faulkes Telescope South optical candidate
- GRB 130722A: Swift detection of a burst
- GRB130702A: Redshift of Afterglow Candidate iPTF13bxl
- GRB 130701A: Swift detection of a burst
- GRB 130626A: KAIT Optical Observations
- GRB 130626A: RATIR Optical Observations
- GRB130627B: Swift/UVOT Observations
- GRB 130626A: Swift-XRT possible detection and UVOT upper limits
- GRB 130627A: Swift/UVOT Observation
- GRB 130626A: Swift detection of a short burst
- GRB 130625A: Swift detection of a burst
- Swift Trigger 558631 is not a real source
- GRB 130615A: Zadko observatory - Gingin optical observations
- GRB 130615A: TAROT La Silla observatory optical observations
- GRB 130615A: GROND afterglow candidate
- GRB 130615A: Swift detection of a burst
- GRB 130612A: Liverpool Telescope Afterglow detection
- GRB 130612A: Swift detection of a burst with an optical counterpart
- GRB 130606B: Swift/UVOT Upper Limit
- GRB 130610A - Liverpool Telescope Optical Afterglow Confirmation
- GRB 130610A: Swift detection of a burst with an optical counterpart
- GRB 130609B: Swift detection of a burst with an optical counterpart
- GRB 130609A: Swift detection of a burst
- GRB 130608A: Swift detection of a burst
- GRB 130606A: Swift detection of a burst
- GRB 130605A: GROND afterglow candidate
- GRB 130605A: Swift detection of a burst
- Swift Trigger 557466 is probably not real.
- GRB 130604A: further ISON-NM optical observation
- GRB 130604A: ISON-NM optical upper limit
- GRB 130604A: P60 optical afterglow candidate
- GRB 130603B: WHT optical afterglow candidate
- GRB 130603B: Swift detection of a bright short burst
- GRB 130529A: Swift detection of a burst
- GRB 130528A: Swift detection of a burst
- GRB 130527A: Swift detection of a bright burst
- Swift Trigger 556533 is probably not an astrophysical event
- GRB 130515A: FORS2 spectroscopy of candidate counterpart
- GRB 130515A: Swift detection of a short burst
- GRB 130514A: Swift detection of a burst
- GRB 130511A: Swift detection of a burst with an optical counterpart
- GRB 130508A: Swift detection of a probable burst
- GRB 130505B: Swift Candidate Afterglow
- GRB 130504A: IAC80 optical candidate
- GRB 130505A: Swift detection of a burst with optical afterglow
- GRB 130504A: Bassano Bresciano Observatory optical upper limit
- GRB 130504A, Swift-BAT refined analysis
- Swift-XRT X-ray afterglow candidate for GRB 130504A (BAT trigger 555096)
- Trigger 555096: Swift detection of a possible burst
- GRB 130502A: Swift/UVOT Upper Limits
- GRB 130502B: P60 Observations
- GRB 130502A: TNG candidate counterpart
- GRB 130502A: Swift detection of a burst
- GRB 130427B: Swift detection of a burst with optical counterpart
- Swift Trigger 554135 is probably not a GRB or transient
- GRB 130420B: Swift detection of a burst
- GRB 130420A: ROTSE-III Detection of Optical Counterpart
- GRB 130420A: Swift detection of a burst with an optical counterpart
- GRB 130420A: Faulkes Telescope North candidate
- GRB 130418A: Bassano Bresciano Observatory optical observations
- GRB 130418A: Swift detection of a burst with an optical counterpart
- GRB 130408A: Swift/UVOT Detection of the Optical Afterglow
- GRB 130408A: Liverpool Telescope Optical candidate detection
- GRB 130407A Tiled Swift observations
- GRB 130211A: Retraction of afterglow candidate
- GRB 130310A: RATIR Observations
- Swift Trigger 552142: a possible GRB
- GRB 130325A Tiled Swift observations
- GRB 130327A: PAIRITEL NIR Afterglow Candidate
- GRB 130327A: Swift detection of a burst
- GRB 130315A: GROND afterglow candidate
- GRB130313A: GTC early optical limits
- GRB 130315A: Swift detection of a burst
- GRB 130313A: Swift detection of a short burst
- Swift XRT RETRACTION of GRB 130310A afterglow detection
- GRB 130215A: Redshift estimate
- GRB 130215: ROTSE-III Detection of Optical Counterpart
- GRB 130211A: Swift detection of a burst
- GRB 130131A: RATIR optical and infrared upper limits
- GRB 130131B: Swift detection of a burst
- GRB 130131A - UKIRT afterglow candidate
- GRB 130131A: Swift detection of a burst
- GRB 130122A: T100 observations
- GRB 130122A: Swift detection of a burst with an optical counterpart
- GRB 130102A: Swift detection of a burst
- GRB 121229A: Swift detection of a burst
- GRB 121226A: Swift detection of a burst