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').
95 results found.
- Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552
- Swift Trigger on AXP CXOU J164710.2-455216/PSR J1647-4552
- LIGO/Virgo G298048: Brightening X-ray Emission from GW170817/GRB170817A/SSS17a
- Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552
- Trigger 780207: Swift triggers again on AXP CXOU J164710.2-455216/PSR J1647-4552
- Swift Trigger on AXP CXOU J164710.2-455216/PSR J1647-4552
- Fermi GBM Detection of possible burst from AXP 4U 0142+61
- AXP CXOU J164710.2-455216: Fermi GBM observation
- Swift Trigger AXP CXOU J164710.2-455216: MASTER-OAFA observations
- Swift Trigger on AXP CXOU J164710.2-455216
- Trigger 706396: Swift detection of a short burst from PSR 1119-6127
- GRB 150301A: Fermi GBM observation
- IPN Triangulation of SGR-like burst 130913 - probable association with SGR/AXP 1E1841-045
- Fermi/GBM observation of the Soft Gamma Repeater SGR J1550-5418
- Trigger 558399: Swift detection of the Soft Gamma Repeater AXP 1E1547.0-5408
- 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
- Swift detection of short bursts from PSR J1647-4552
- SGR J1834.9-0846: A Neutron Star in W41?
- 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?
- Swift-BAT refined analysis of trigger 421262
- An SGR-like burst from the magnetar 1E 1841-04.5 in Kes 73
- GRB 091117: Chandra Observations
- 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
- 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 071017: a SHORT GRB detected by INTEGRAL
- Swift detects a hard X-ray burst from AXP CXOU J164710.2-455216
- GRB040912(=H3557): Chandra Candidate X-ray Afterglow
- GRB040912(=H3557): Observations with the Chandra X-ray Observatory
- XRF040701: Optical Observations at ESO
- XRF040701: VLA Observations
- XRF040701: Magellan Spectroscopy of Chandra Source #2 Associated Galaxy
- XRF040701: First-Epoch Chandra Observations
- GRB031220(=H2976): TNG R-band Observation of the Chandra X-ray Sources
- GRB031220(=H2976): Observation with the Chandra X-ray Observatory
- IPN detection of continued activity from SGR1806-20
- XRF030723(=H2777): Chandra Observations
- GRB030528(=H2724): X-ray Afterglow Identified in Second Epoch
- GRB 030528: Infrared Observations and the Proposed IR Counterpart
- GRB 030528: Optical Observations
- GRB 030528: tentative NIR counterpart
- GRB030528(=H2724): Observations with the Chandra X-ray Observatory
- 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
- GRB 020531/Candidate Redshift
- GRB020531: Detection of Candidate Host Galaxy
- GRB020531: Second epoch Chandra observations
- GRB020531 Optical observations with TAROT
- GRB020531 Optical observations with TAROT
- GRB020531: Observations with the Chandra X-ray Observatory
- XRF020427: Chandra Identification of a Likely X-ray Counterpart
- XRF020427: Chandra Observations and Candidate X-ray Counterparts
- GRB 020321: Candidate X-ray Counterparts
- GRB011130 (XRF011130) Second Epoch Chandra Observations
- GRB 011130: Optical Observations of X-ray and Radio Sources
- GRB 011130, Radio/X-ray Comparison
- GRB011130 (=XRF011130): Further analysis of Chandra Target of
- GRB 011130: Optical Observations of Chandra Sources
- GRB 011130: Optical Observations of Chandra sources
- GRB011130 (XRF011130) Chandra Observations