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').
269 results found.
- Swift GRB190613.17 Global MASTER-Net observations report
- Fermi trigger No 581841498 Global MASTER-Net observations report
- Fermi Fermi trigger No 581002688 Global MASTER-Net observations report
- Fermi GRB190525.67 Global MASTER-Net observations report
- LIGO/Virgo S190521r Global MASTER-Net observations report
- LIGO/Virgo S190519bj Global MASTER-Net observations report
- Fermi GRB190517.81 Global MASTER-Net observations report
- LIGO/Virgo S190517h Global MASTER-Net observations report
- Fermi GRB190515.43 Global MASTER-Net observations report
- LIGO/Virgo S190513bm Global MASTER-Net observations report
- LIGO/Virgo S190512at Global MASTER-Net observations report
- Fermi GRB190510.12 Global MASTER-Net observations report
- LIGO/Virgo S190503bf Global MASTER-Net observations report
- LIGO/Virgo S190426c: RATIR Optical and NIR Observations of Galaxies
- LIGO/Virgo S190425z: RATIR Observations of Galaxies
- SWIFT GRB190324.95 Global MASTER-Net observations report
- SWIFT GRB190320.05 Global MASTER-Net observations report
- GRB190311A: MITSuME Akeno optical observation
- GRB190311A: MASTER Global Robotic Net OT optical observation
- Swift Trigger 887541: MASTER inspect
- GRB190123A: MITSuME Akeno optical upper limits
- GRB 190117A: AGILE/MCAL detection of a burst
- GRB 190114C: LSGT optical observation
- GRB 190114A: Swift/UVOT Observations
- Short-duration GRB 181121.4: MASTER-Tavrida possible OT detection near the PGC galaxy during large Fermi error box inspection
- GRB 181110A: Swift/UVOT Detection
- GRB 181003A: MASTER optical observation
- GRB 180925A: Swift/UVOT Detection
- GRB 180728A: MASTER early polarization and 19 days monitoring
- GRB 180720B: MITSuME Akeno optical observations
- IceCube-171106A: MASTER optical observation
- GRB 180705A: MASTER optical observation
- GRB 180624A: Swift-BAT refined analysis
- GRB 180620A iTelescope observation
- Fermi-GBM Detection of possible burst from AXP CXOU J164710.2-455216/PSR J1647-4552
- GRB 180205A: Swift/UVOT Detection
- Swift Trigger on AXP CXOU J164710.2-455216/PSR J1647-4552
- GRB 171205A: Host galaxy photometric properties
- GRB 171027A: MASTER-OAFA (Argentina) early prompt optical observations
- 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
- GRB 171007A: Swift/UVOT Upper Limits
- 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
- Short GRB 170428A: MASTER-OAFA final reduction of the optical observations
- GRB 170205A: Swift/UVOT Detection of a Fading Afterglow
- LIGO/Virgo G270580: Las Cumbres Observatory Follow-up Observations
- GRB 170127B: MASTER-Kislovodsk early optical observations
- GRB 161017A: Lomonosov Gamma Ray and MASTER Optical prompt observations
- Trigger 706396: Swift detection of a short burst from PSR 1119-6127
- GRB 160726A: Fermi GBM observation
- GRB 160714A: MASTER early optical observations
- GRB 160227A: Swift/UVOT Detection
- GRB 160227A: MASTER prompt OT Detection and LC
- GRB 160131A Swift/UVOT Detection
- GRB 151210A: GROND Afterglow Confirmation
- GRB 150818A: MITSuME Akeno optical upper limits
- GRB 150301A: Fermi GBM observation
- GRB 150212A: MASTER optical observations
- GRB 141026A: Gemini-North optical and NIR imaging
- Swift observations of HD 305560
- GRB 140930A/MAXI J2259+524: MASTER optical observations
- GRB 140907A: MASTER optical observations
- GRB 140614B: Swift/UVOT Upper Limits
- GRB 140610A: MASTER optical observations
- GRB 140423A: TShAO optical observations
- GRB 140508A: SAO RAS and MASTER photometric and spectroscopic observations
- GRB 140129B: MASTER OT early light curve
- GRB 140103A: MASTER-Net early OT detection
- IPN Triangulation of SGR-like burst 130913 - probable association with SGR/AXP 1E1841-045
- GRB 130725B: Swift/UVOT Observations
- Fermi/GBM observation of the Soft Gamma Repeater SGR J1550-5418
- Trigger 558399: Swift detection of the Soft Gamma Repeater AXP 1E1547.0-5408
- GRB 130511A: SSO 2.3m observation
- GRB 130427A: Spectroscopic detection of the SN from the 10.4m GTC
- GRB 130427A: photo-z of possible SDSS host galaxy
- 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?