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"27408 results found.
- Fermi GBM detection of GRB 130925A and a possible precursor
- GRB 130925A: Swift-XRT refined Analysis
- GRB 130925A: Initial Similarities to Swift J1644+57
- GRB 130925A: TAROT La Silla observatory optical observations
- GRB 130925A: VLT/X-shooter redshift
- GRB 130925A: VLT/UVES observations
- GRB 130925A: GROND afterglow candidate
- GRB 130925A: Swift detection of a burst
- IPN Triangulation of SGR-like burst 130913 - probable association with SGR/AXP 1E1841-045
- GRB 130831A: RATIR Confirmation of NIR/Optical Afterglow Flattening
- Fermi Trigger 401326696: MASTER prompt optical observations
- INTEGRAL detection of a SGR-like burst likely from SGR J1745-29
- GRB 130919A: Skynet PROMPT-CTIO optical upper limits
- GRB 130919A, Swift-BAT refined analysis
- GRB 130913A detected in ground analysis of Swift-BAT data
- GRB 130919A: Swift detection of a burst
- GRB 130606A: Chandra observation
- GRB 130912A: Swift/UVOT Upper Limits
- Fermi/GBM Detection of two SGR-like bursts possibly associated with SGR J1833-0832
- GRB 130912A: RATIR Optical and NIR Upper Limits
- Konus-Wind observation of GRB 130912A
- GRB 130912A: WHT confirmation of optical counterpart
- GRB 130907A: Continued RATIR Optical and NIR Observations
- GRB 130912A: P60 Observations
- GRB 130912A: Swift-XRT refined Analysis
- GRB 130907A: MASTER refined analysis
- GRB 130912A: Fermi GBM detection
- GRB 130912A: Skynet DSO-14/Yerkes-41/PROMPT-CTIO observations
- GRB 130912A, Swift-BAT refined analysis
- GRB 130912A: GROND observations
- GRB 130912A: Swift detection of a short burst
- GRB 130907A: Continued RATIR Optical and NIR Observations
- GRB 130907A: RATIR Optical and NIR Observations
- GRB 130907A: Further Swift-BAT refined analysis
- GRB 130907A: INTEGRAL/SPI-ACS light curve
- Konus-Wind observation of GRB 130907A
- GRB 130907A, Swift-BAT refined analysis
- GRB 130907A: Swift-XRT refined Analysis
- GRB 120916A: Fermi-LAT detection of a burst
- GRB 130907A: Swift/UVOT Detection
- GRB 130907A: Early Tautenburg detections, red afterglow
- GRB 130907A: Skynet DSO-14/Yerkes-41/GORT confirmation of a fading afterglow
- GRB 130907A: RATIR Optical and NIR Afterglow Confirmation
- GRB 130907A: Skynet DSO-14/Yerkes-41 detections of a possible afterglow
- GRB 130831A: Maidanak optical observations
- GRB 130831A: ISON-UAFO optical observations
- GRB 130907A: Swift detection of a burst with an optical counterpart
- Swift follow-up results of the possible weak INTEGRAL GRB
- GRB 130903A: Swift/UVOT Upper Limits
- Swift follow-up of an INTEGRAL possible weak GRB
- GRB 130831A: RATIR Optical and NIR Upper Limits
- GRB 130903A: GROND Afterglow Discovery
- GRB 130903A: Fermi GBM observation
- GRB 130831A: JCMT SCUBA-2 sub-mm observation
- GRB 130903A: Swift-XRT observations
- Swift trigger 569022 is a new Galactic source Swift J1734.5-3027
- GRB 130903A: ISON-Kislovodsk optical Upper Limits
- GRB 130903A: GROND Upper Limits
- GRB 130831A: Swift/UVOT Observations
- GRB 130831A: Montarrenti Observatory optical follow-up
- GRB 130831A: RATIR Optical and NIR Observations
- GRB 130831A: Continued Skynet/PROMPT-SSO, PROMPT-CTIO and Yerkes-41 detections
- GRB 130831B, Swift-BAT refined analysis
- GRB 130831A: T100 observations
- GRB 130831B: Swift/UVOT Upper Limits
- GRB 130831B: GROND upper limits
- Swift Trigger 569022: a possible GRB
- GRB 130831A: THO optical observation
- GRB 130831A, Swift-BAT refined analysis
- GRB 130831B: Swift-XRT refined Analysis
- GRB 130831A: optical observations
- GRB 130831A: Swift-XRT refined Analysis
- GRB 130831A: Montarrenti Observatory optical observations
- GRB 130831A: Skynet/PROMPT-SSO detections
- Konus-Wind observation of GRB 130831A
- GRB 130831A: Gemini-North Redshift
- GRB 130831B: Swift detection of a burst
- GRB 130831A: Faulkes Telescope North and South optical afterglow
- GRB 130831A: Swift detection of a burst with an optical counterpart
- IPN triangulation of GRB 130828A - error box
- GRB 130829A: AAO optical observations
- GRB 130828A: Swift XRT and UVOT observations
- GRB 130829A: NOT optical observations
- IPN triangulation of GRB 130828A
- GRB 130829A: Swift detection of a burst
- GRB 130828A: Fermi GBM detection
- GRB 130828A: Fermi-LAT detection of a burst
- GRB 130822A Swift-BAT Spectral lag analysis
- GRB 130821A: Swift-XRT observation
- GRB 130822A: Gemini Observations
- GRB 130822A: Swift-XRT refined Analysis
- GRB 130822A: Swift/UVOT Upper Limits
- GRB 130822A, Swift-BAT refined analysis
- GRB 130821A: Fermi-LAT detection of a burst
- GRB 130822A: Weihai optical upper limit
- GRB 130821A: Fermi GBM Detection
- GRB 130822A: Swift detection of a short burst
- GRB 130816A: Swift/UVOT Upper Limits
- GRB 130816B: Swift/UVOT Upper Limits
- Fermi Gamma-ray Burst Monitor trigger 398555975 / 130818916 is not a GRB