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.
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To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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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.
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subject:"Swift"body:"GRB"submitter:"Judith Racusin"- Ongoing activity of AXP/SGR 1E1547.0-5408
- GRB 090222: Fermi GBM detection
- GRB 090219: Fermi GBM detection
- Swift Restored
- Swift Trigger 343319 is not a GRB
- GRB 090217: Suzaku WAM observation of the prompt emission
- GRB090217: XRT analysis
- Konus-Wind observation of GRB 090217
- IPN localization of GRB 090217
- GRB 090213: Fermi GBM detection
- GRB090217: Fermi-LAT Detection
- GRB 090217: Fermi GBM detection
- SGR activity seen by BAT during ICSP Ionospheric Events
- Detailed lightcurves of ICSP VLF Observation of SGR/AXP 1E1547.0-5408
- GRB 090207 - Fermi GBM Observations
- Fermi Gamma-ray Burst Monitor trigger 255729682 is not a GRB
- GRB 090129: Fermi GBM detection
- VLA radio upper limit on GRB 090205
- GRB 090205: VLT optical decay
- Fermi Gamma-ray Burst Monitor trigger 255541748 cannot be classified
- GRB 090205: Swift/UVOT Upper Limits
- GRB 090205: VLT refined redshift
- GRB 090205: Swift-XRT refined analysis
- GRB 090205: Swift burst of interest
- GRB 090205: VLT spectroscopic redshift
- GRB 090205: GROND observations and photometric redshift estimate
- GRB 090205: VLT candidate afterglow
- GRB 090205: Swift-BAT refined analysis
- GRB 090205: Enhanced Swift-XRT position
- GRB 090205: Swift detection of a burst
- GRB 080319B: IceCube upper limit on high-energy neutrino flux
- GRB 090131: Suzaku WAM observation of the prompt emission
- ICSP VLF observation of the signatures of SGR/AXP 1E1547.0-5408 bursts
- GRB 090126A: Swift-XRT afterglow confirmation
- Fermi Gamma-ray Burst Monitor trigger 255342766 is not a GRB
- Konus-Wind observation of GRB 090201
- GRB 090202: Fermi GBM detection
- GRB 090131: Fermi GBM detection
- GRB 090201: Swift-XRT refined analysis
- GRB090201: Swift UVOT upper limits
- GRB 090201: object inside the enhanced XRT error circle
- GRB 090201: Enhanced Swift-XRT position
- GRB 090201: VLT NIR observations
- GRB 090201: Swift-BAT refined analysis
- GRB 090201: VLT afterglow candidate
- GRB 090201: Swift-XRT detection of the possible X-ray afterglow
- GRB090113: MAGIC telescope GeV observation
- GRB 090201: ROTSE-III Optical Limits
- GRB 090201: Swift detection of a burst
- GRB 090126A: Swift/UVOT Upper Limits
- Konus-Wind observation of bright burst from AXP/SGR 1E1547.0-5408 on January 29
- GRB 090129: Swift-BAT refined analysis
- GRB 090129: Swift detection of a burst
- IBAS Alert N. 5442 is not a GRB
- Suzaku ToO Observation of AXP 1E 1547.0-5408
- Konus-Wind observation of AXP/SGR 1E1547.0-5408 bursting activity
- AXP 1E1547.0-5408: RHESSI observations up to 400 keV
- GRB 090102: HST observations and host galaxy
- GRB 090126C: Fermi GBM detection
- GRB 090126A: Swift-XRT Refined Analysis
- GRB 090126B: Fermi GBM detection
- GRB 090126: SuperAGILE Localization of a Long GRB
- Konus-Wind detection of very bright SGR-like burst on January 25, 2009
- GRB 090118: no afterglow candidate
- GRB 090123: GROND detection
- 1E1547.0-5408: Swift detection of dust halo
- GRB 090123: Swift XRT refined analysis
- GRB 090123: Swift/UVOT Observations
- AXP 1E1547.0-5408: Suzaku WAM detections of the current activity
- GRB 090123: Swift-BAT refined analysis
- GRB090123: Enhanced Swift-XRT position
- GRB 090123: Swift detection of a burst
- AXP 1E1547.0-5408: long bursts with INTEGRAL SPI-ACS
- GRB 090118: Swift XRT Observations - Confirmation of an Afterglow
- Swift-BAT trigger 340734 is not a GRB
- AXP 1E1547.0-5408: Fermi GBM detection of additional bursts
- AXP 1E1547.0-5408: INTEGRAL SPI-ACS confirms activity increase
- GRB 090117C: Suzaku WAM observation of the prompt emission
- AXP 1E1547.0-5408: Fermi GBM observations
- Trigger 340734: Swift detection of a possible short burst
- AXP 1E1547.0-5408 activity with SGR bursts
- GRB 090118: Subaru NIR Observation
- GRB 090118: KPNO 4m 2nd Epoch Observations
- GRB 090118 (BATSS): GRT Optical Observation
- GRB 090118: KPNO 4m Detection of Candidate Afterglow
- GRB 090118: Swift-XRT observations
- GRB090118 Swift/UVOT upper limits
- GRB 090118: GROND Upper Limits
- GRB 090118: Possible burst detection from Swift-BAT slew data
- GRB 090117B : Fermi GBM detection
- GRB 090117: confirmation of the X-ray afterglow
- GRB 090117C - Fermi GRB Detection
- GRB 090117 - Fermi GBM Observations
- GRB 090117: GROND Upper Limits
- GRB090117 Swift/UVOT upper limits
- GRB090117: Swift-XRT detection of a possible candidate afterglow
- GRB 090117 - SuperAGILE Localization of a long GRB
- GRB090102: MAGIC telescope GeV observation
- GRB 090112B: Suzaku WAM observation of the prompt emission
- GRB 090113: LOAO Detection Limits in R, I, z, Y-band