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.
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"
290 results found.
- GRB 130420B: Faulkes Telescope North observations
- GRB 130102A: Swift/UVOT Upper Limits
- GRB 121229A: GROND detection of the afterglow
- GRB 121217A: Swift/UVOT Detection
- GRB121212A: Swift/UVOT Detection
- GRB 121028A: Swift/UVOT Upper Limits
- GRB 121012A: Fermi GBM detection
- GRB 120328A: Swift/UVOT Upper Limits
- GRB 120305A: Swift/UVOT Upper Limits
- AXP 4U 1042+61: Mondy optical observations
- AXP 4U 0142+61: Swift-BAT refined analysis (trigger 511611)
- Swift detection of an SGR burst from AXP 4U 0142+61
- GRB 111107A: Swift/UVOT Afterglow Analysis
- GRB 111022B: MITSuME Akeno Optical upper limits
- GRB 111016A: Swift-BAT refined analysis
- GRB 110921A: Swift/UVOT Observations
- GRB 110915A: Swift/UVOT Upper Limits
- AXP 4U 0142+61: Fermi GBM detection
- AXP 4U 0142+61: Swift-BAT refined analysis
- Swift detection of a SGR-like burst from the AXP 4U 0142+61
- Swift J1822.3-1606: Transient Magnetar or Be X-ray Binary?
- GRB 110420B: Swift/UVOT Upper Limits
- Swift/UVOT observations of GRB110223b
- GRB 101008A: MASTER prompt optical observations (correction to GCN#11328)
- GRB 101008A: MASTER prompt optical observations
- GRB 100909A: Faulkes Telescope North afterglow candidate
- GRB 100905A: Swift/UVOT Upper Limits
- GRB 100823A: Candidate IR afterglow
- Swift-BAT refined analysis of trigger 421262
- An SGR-like burst from the magnetar 1E 1841-04.5 in Kes 73
- GRB 100413A: Faulkes Telescope South observations
- GRB 100206A: Swift/UVOT Upper Limits
- GRB 090814B: Liverpool Telescope Observations
- GRB090423 - Swift/UVOT upper limits.
- GRB 090419: Swift/UVOT Observations
- GRB 090417B: Gemini imaging
- A bright burst from AXP 1E 1547.0-5408/SGR J1550-5418
- ATCA observation of SGR J1550-5418
- Konus-RF catches first GRB and SGR bursts
- SGR J1550-5418
- Ongoing activity of AXP/SGR 1E1547.0-5408
- SGR activity seen by BAT during ICSP Ionospheric Events
- Detailed lightcurves of ICSP VLF Observation of SGR/AXP 1E1547.0-5408
- ICSP VLF observation of the signatures of SGR/AXP 1E1547.0-5408 bursts
- Konus-Wind observation of bright burst from AXP/SGR 1E1547.0-5408 on January 29
- 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
- Konus-Wind detection of very bright SGR-like burst on January 25, 2009
- AXP 1E1547.0-5408: Suzaku WAM detections of the current activity
- AXP 1E1547.0-5408: long bursts with INTEGRAL SPI-ACS
- 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
- AXP 1E1547.0-5408: Fermi GBM observations
- Trigger 340734: Swift detection of a possible short burst
- AXP 1E1547.0-5408 activity with SGR bursts
- Swift/UVOT observations of GRB 081221
- Fermi GBM detection of additional bursts from AXP 1E1547.0-5408
- INTEGRAL ToO observation of the AXP 1E 1547.0-5408
- AXP 1E 1547.0-5408: Swift/UVOT Upper Limits
- AXP 1E1547.0-5408: Swift-XRT Team refined analysis
- Swift-BAT refined analysis of AXP 1E1547.0-5408 (Trigger 330353)
- AXP 1E1547.0-5408 (SGR 1550-5418): Fermi GBM detection
- SGR 1550-5418 = AXP 1E1547.0-5408 (Trigger 330353)
- Trigger 330353: Swift detection of a Galactic short soft burst
- GRB 071021: Magellan R-band observation
- GRB 071017: a SHORT GRB detected by INTEGRAL
- Swift/UVOT refined analysis of GRB070529
- Swift detects a hard X-ray burst from AXP CXOU J164710.2-455216
- GRB 060522: Swift/XRT Team refined analysis
- GRB 060202: Swift XRT Team Refined Analysis
- GRB050915: P60 Optical Observations
- IPN detection of continued activity from SGR1806-20
- GRB 030329 Optical Observations
- Gemini IR Detection of AXP 1E 2259+586 Post-Burst
- SGR-like X-ray Bursts from AXP 1E 2259+586: follow-up
- AXP 1E2259+586: quasi-simultaneous optical observation
- AXP 1E2259+586 optical observations
- SGR-like Bursts from the AXP 1E 2259+586
- GRB010923 as seen by BeppoSAX GRBM
- GRB Observation Report
- GRB990705, VLT-FORS1 observations of the host galaxy
- Optical observations of GRB000210
- GRB 000210: BATSE Observations
- GRB000210, Radio Observations
- IPN triangulation of GRB000210
- GRB991216 Optical and IR observations
- GRB 981220, radio observations