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"19352 results found.
- GRB 131002B: Swift-XRT Refined Analysis
- GRB 131002B: Swift/UVOT Upper Limits
- GRB 131002A: Swift/UVOT Detection
- GRB 131001A, Swift-BAT refined analysis
- GRB 131002A: Swift-XRT refined Analysis
- GRB 131002B: Enhanced Swift-XRT position
- GRB 131002A: ISON-NM optical observations
- Swift J1242.9-3530, Swift-BAT refined analysis
- GRB 131001A: Swift UVOT and XRT Upper Limits
- GRB 131002A: Enhanced Swift-XRT position
- NuSTAR observations of GRB 130925A
- GRB 131002B: Swift detection of a burst
- GRB 131002A: Swift detection of a burst
- GRB 131001A detected in ground analysis of Swift-BAT data
- GRB 130925A: continuing Swift/XRT monitoring
- Swift Operations in the event of a US Government shutdown
- IPN Observations of GRB 130925A
- GRB 130930A: Swift detection of a burst
- GRB 130929A: Swift/UVOT Upper Limits
- GRB 130831A: Continued RATIR Optical and NIR Observations
- GRB 130929A: Swift-XRT refined Analysis
- GRB 130929A, Swift-BAT refined analysis
- GRB 130929A: Enhanced Swift-XRT position
- GRB 130929A: TAROT La Silla observatory optical observations
- GRB 130929A: Swift detection of a burst
- GRB 130925A: Swift/UVOT Detection of the Host Galaxy
- GRB 130925A: Swift/UVOT Upper Limits
- GRB 130925A: sub-mm non-detection with SMA
- GRB 130925A: Continued RATIR Optical and NIR Observations
- GRB 130925A: Fermi GBM Detection
- Konus-Wind observation of GRB 130925A
- Observation of possible GRB/TDE 130925A by INTEGRAL/SPI-ACS: three activity episodes
- GRB 130925A: RATIR Optical and NIR Observations
- GRB 130925A Swift-BAT refined analysis
- GRB 130925A: Historical non-detection from Rosat-HRI
- 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: Enhanced Swift-XRT position
- GRB 130925A: VLT/X-shooter redshift
- GRB 130925A: VLT/UVES observations
- GRB 130925A: MAXI/GSC detection
- 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
- GRB 130907A: Maidanak optical observations
- GRB 130912A: AAO optical upper limit
- GRB 130831A: Maidanak optical observations, possible emerging Supernova
- 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 130903A: Further Swift XRT observations.
- GRB 130606A: Chandra observation
- GRB 130912A: Swift/UVOT Upper Limits
- GRB 130912A: RATIR Optical and NIR Upper Limits
- Konus-Wind observation of GRB 130912A
- 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: Enhanced Swift-XRT position
- GRB 130912A, Swift-BAT refined analysis
- GRB 130912A: GROND observations
- GRB 130912A: Swift detection of a short burst
- GRB 120419A: Swift XRT confirmation of the afterglow
- GRB 130828A: Further Swift XRT 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 130907A: Enhanced Swift-XRT position
- 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: optical observation in Chuguev AO
- GRB 130831A: ISON-Kislovodsk optical observations
- GRB 130831A: optical observation in Gissar AO
- GRB 130831A: ISON-UAFO optical observations
- GRB 130907A: MASTER early OT 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: Fermi GBM observation
- GRB 130903A: Swift-XRT observations
- Swift trigger 569022 is a new Galactic source Swift J1734.5-3027
- 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