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').
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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"- SGR 1935+2154: AMI 15 GHz upper limits of the magnetar during outburst
- GRB 160625B: VLA Detection
- GRB 160625B: TSHAO optical observations
- Konus-Wind observation of GRB 160625B
- GRB 160625B: Mini-MegaTORTORA detection of bright optical flash simultaneous with LAT event
- GRB 160625B: RATIR Optical and NIR Observations
- GRB 160625B: TNG redshift confirmation
- GRB 160625B: VLT/X-shooter redshift
- GRB 160625B: MITSuME Ishigakijima Optical Observation
- Fermi/GBM observation of a bright burst from magnetar SGR 1935+2154
- GRB 160623A CALET Gamma-Ray Burst Monitor detection
- Swift-BAT refined analysis on the bright event from SGR 1935+2154
- Swift Trigger 701668 is probably not an astrophysical event
- IPN Triangulation of GRB 160620A (short/hard)
- GRB 160625A: Swift/UVOT Upper Limits
- GRB 160625A: Swift-BAT refined analysis
- GRB 160625A: Swift-XRT refined Analysis
- Trigger 701590: Swift detection of a bright outburst from SGR 1935+2154
- GRB 160625B: Swift/UVOT Detection
- GRB 160625B: RATIR Optical and NIR Afterglow Detection
- GRB 160625B: Fermi GBM refined analysis
- GRB 160625B: Fermi-LAT refined analysis
- GRB 160625B: Swift-XRT afterglow detection
- GRB 160623A: SMA submm afterglow observations
- GRB 160625A: Enhanced Swift-XRT position
- GRB 160625B: Tiled Swift observations
- GRB 160625B: Fermi GBM initial observations
- GRB 160625B: Fermi-LAT detection of a bright burst
- GRB 160625A - two different events?
- GRB 160625A: Swift-XRT observations
- GRB 160625A: Swift detection of a burst
- GRB 160624A: Swift/UVOT Upper Limits
- GRB 160624A: Lulin observation
- GRB 160623A: TSHAO optical observations
- GRB 160624A: Swift-XRT refined Analysis
- GRB 160623A: MITSuME Ishigakijima Optical Observation
- GRB 160624A: MITSuME Ishigakijima upper limits
- GRB 160624A: Fermi GBM observation
- GRB 160624A, Swift-BAT refined analysis
- GRB 160623A: Swift/UVOT Upper Limits
- GRB 160623A: RATIR Optical and NIR Observations, Afterglow Confirmation
- GRB 160624A: Enhanced Swift-XRT position
- GRB160624A:possible GRB host redshift
- GRB 160525B: 15 GHz upper limits from AMI
- GRB 160521B: 15 GHz upper limits from AMI
- GRB 160624A: Prompt enhanced Swift-XRT position
- GRB 160623A: Mondy optical observations
- GRB 160624A: Swift detection of a short burst
- Swift detection of a dust-scattered halo around GRB 160623A
- GRB 160623A: Swift-XRT afterglow detection
- GROND observations of GRB 160622A/SNR RCW 103/SGR 1617-5103
- Trigger 701182: Swift detection of SGR 1935+2154
- GRB 160623A: Fermi GBM detection/observation
- Konus-Wind observation of GRB 160623A
- GRB 160623A / Galactic transient: Fermi-LAT detection
- GRB 160623A: Swift ToO observations
- SGR 1617-5103 (BAT trigger 700791): Enhanced Swift-XRT position.
- Swift-BAT refined analysis of the recent outburst from SGR 1617-5103 (a.k.a. 1E 161348-5055 and 2E 1613.5-5053)
- Fermi GBM Trigger 160622573 is not a GRB
- BAT trigger 700791 (possible GRB 160622A) is SNR RCW 103
- GRB 160622A: Swift detection of a possible short GRB or a new SGR
- More FERMI GBM bursts from the magnetar SGR 1935+2154
- SGR 1935+2154: MAXI/GSC detection
- Fermi GBM trigger 488128598/160620637 is not a GRB
- Fermi GBM trigger 487974449/160618852 is not a GRB
- LIGO/Virgo G211117 / GW151226: Sky maps and other data available in LOSC
- LIGO/Virgo G197392 / LVT151012: Sky maps and other data available in LOSC
- LIGO/Virgo G211117/GW151226: serendipitous XMM-Newton slew observations
- Konus-Wind observation of GRB 160612A
- GRB 160612A: Swift-XRT observations
- BAT detection and localization of GRB 160612A
- GRB 160612A: Swift ToO observations
- IPN Triangulation of GRB 160612A (short/hard)
- GRB 160521A: 15 GHz detections and upper limit from AMI
- GRB 160519A: 15 GHz upper limits from AMI
- GRB 160509A: 15 GHz upper limits from AMI
- GRB 160612A: Fermi GBM detection
- GRB 160611A: Swift/UVOT observations
- GRB 160611A: Swift-BAT refined analysis
- Swift Trigger 690738 is not an astrophysical event
- GRB 160611A: Swift-XRT refined Analysis
- GRB 160611A: GCN19525 OT is known star
- GRB160611.9 MASTER-Net OT detection
- GRB 160611A: Enhanced Swift-XRT position
- GRB 160611A: Swift-XRT observations
- GRB 160611A: Swift detection of a burst
- SWIFT J174540.2-290037, Swift-BAT refined analysis (trigger 690197)
- GRB 160525C: Astrosat CZTI detection
- GRB 160508A: Astrosat CZTI detection
- SWIFT J174540.2-290037, Swift-BAT refined analysis (trigger 689956)
- GRB 160607A CALET Gamma-Ray Burst Monitor detection
- Swift detection of SWIFT J174540.2-290037
- Swift detection of SWIFT J174540.2-290037
- Trigger 689956: Swift detection of a source near the Galactic center
- GRB 160607A: Swift/UVOT Upper Limits
- GRB 160607A: GROND confirmation of the afterglow
- Konus-Wind observation of GRB 160607A
- GRB 160504A: 15 GHz upper limits from AMI
- GRB 160417A: 15 GHz upper limits from AMI
- GRB 160408A: 15 GHz upper limits from AMI