GCN Circulars
GCN Circulars are rapid bulletins submitted by and distributed to the community. 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').
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.
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subject:"Swift"body:"GRB"submitter:"Judith Racusin"- GRB 130327A: PAIRITEL NIR Afterglow Candidate
- GRB 130325A: Fermi LAT detection
- GRB 130327A: Swift detection of a burst
- report: GRB 130315A: Zadko observatory - Gingin optical observations
- GRB 130325A: Fermi GBM detection
- Konus-Wind observation of GRB 130320A
- IPN Triangulation of GRB 130320A (long/very bright)
- GRB 130305A: Gemini follow-up observations
- GRB 130315A: GROND afterglow candidate
- GRB 130305A: optical upper limit in Mondy observatory
- GRB 130315A: Swift/UVOT Upper Limits
- GRB 130313A: optical upper limit in CrAO
- GRB 130313A: optical upper limit in Mondy observatory
- GRB 130315A: SALT optical observations
- GRB130313A: GTC early optical limits
- GRB 130313A: 5.8 GHz VLA upper limit
- GRB 130315A: Swift-XRT refined Analysis
- Swift XRT observations of GRB 130310A
- GRB 130315A, Swift-BAT refined analysis
- GRB 130313A: Swift/UVOT Upper Limits
- GRB 130305A: PTF P48 optical upper limits
- GRB130315A BOOTES-3 optical limit
- GRB 130315A: Swift detection of a burst
- GRB 130310A : Suzaku WAM observation of the prompt emission
- GRB 130305A: TLS Tautenburg observations
- GRB 130313A: RATIR Optical and NIR Observations
- GRB 130313A: TNG optical observations
- GRB 130313A: Swift-BAT Spectral lag analysis
- GRB 130313A: Fading X-ray Afterglow
- Swift-BAT trigger 551030 is not astrophysical
- GRB 130215A: Detection of the SN with the 10.4m GTC
- GRB130313A: Optical observations from GTC
- GRB 130313A: NOT optical upper limit
- GRB 130313A: Swift-XRT refined Analysis
- GRB 130313A: simultaneous and follow-up optical observations at BOOTES-3 and BOOTES-4
- GRB 130313A: Weihai optical upper limit
- GRB 130313A: Swift-XRT detection of a possible X-ray afterglow
- GRB 130313A: Swift-BAT refined analysis
- GRB 130313A: Zadko observatory - Gingin optical observations
- GRB 130313A: MASTER-Net optical observations
- GRB 130313A: Swift detection of a short burst
- IPN Triangulation of GRB 130307A
- GRB 100424A: Keck host detection and VLT/X-shooter redshift
- Swift XRT RETRACTION of GRB 130310A afterglow detection
- GRB 130310A: optical observations
- Swift XRT observations of GRB 130310A
- GRB 130306A: Swift Detection of a Possible Afterglow
- GRB 130131B: host detection and redshift
- Konus-Wind observation of GRB 130310A
- IPN triangulation of GRB 130310A
- GRB 130310A: Fermi GBM detection
- GRB 130310A: Fermi-LAT detection and localization
- GRB 130131A: JCMT SCUBA-2 sub-mm observations
- GRB 130306A: MITSuME Ishigakijima upper limits
- GRB 130306A: Swift-BAT refined analysis
- IPN triangulation of GRB 130228A
- GRB 130305A BAT refined circular
- GRB 130305A: Further Swift-XRT Observations
- Konus-Wind observation of GRB 130306A
- GRB 130305A: Optical Observations
- GRB 111123A: Keck-I host detection and VLT/X-shooter redshift
- GRB 130305A: Gemini-North upper limit
- GRB 130307A: Fermi GBM detection
- GRB 130306A: Fermi GBM observation
- GRB 130306A: MASTER-Net pre-Swift alert observation
- GRB 130305A: Swift/UVOT Upper Limit
- GRB 130305A: RATIR Observations
- GRB 130306A: Swift detection of a burst
- GRB 130305A: P60 Observations
- GRB 100615A: HST host detection and X-shooter redshift
- GRB 130305A: Swift/XRT detection of the afterglow
- Konus-Wind observation of GRB 130305A
- GRB 130305A: Fermi GBM observation
- GRB 130305A: Fermi LAT Detection
- Fermi GBM trigger 130301.638 is not GRB
- GBM trigger 383712005 (GRB 130228A?) : Possible high-energy photon emission in Fermi/LAT data
- GRB 130305A found in ground analysis of Swift/BAT data
- GRB 121128A: optical observations in Mondy observatory
- GRB 121128A: optical upper limit in Maidanak observatory
- GRB 130216A: Swift/UVOT Upper Limit
- GRB 130219A: Suzaku WAM observation of the prompt emission
- SGR 1806-20 outburst (trigger 549841), Swift-BAT refined analysis
- Trigger 549841: Swift detection of SGR1806-20
- Konus-Wind observation of GRB 130219A
- GRB 130216B: Suzaku WAM observation of the prompt emission
- GRB 130216A: possible radio counterpart is steady field source
- GRB 130216A: Swift/XRT observations
- IPN Triangulation of GRB 130219A
- GRB 130215A: Suzaku WAM observation of the prompt emission
- GRB 130215A: PTF P48 optical detection
- GRB 130219A: Fermi GBM detection
- GRB 130216B: Swift/XRT observations
- GRB 130216A: Further Swift-BAT refined analysis
- GRB 130216B: MASTER-Net early observation
- GRB 130216A: MASTER-Net early observations
- GRB 130215A: Continued RATIR Optical and NIR Monitoring
- GRB 130216A: Fermi GBM observation
- GRB 130216B: Fermi GBM observation
- GRB 130216A: possible early detection at 15 GHz
- GRB 130216A: MITSuME Ishigakijima upper limits