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').
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"26292 results found.
- Swift Trigger 553930 is not an astrophysical source
- GRB 130419A, Swift-BAT refined analysis
- GRB 130419B (Swift trigger Trigger 553930): MASTER-Net optical observations
- Trigger 553930: Swift detection of a possible flare from HR 5110
- GRB 130418A, Swift-BAT refined analysis
- GRB 130419A: Swift detection of a burst
- GRB 130418A: RATIR Optical and NIR Observations
- GRB 130418A: GROND detection of the optical-NIR afterglow
- GRB 130418A: Swift/UVOT Detection and request for continuing coverage
- GRB 130418A: TAROT Calern and TAROT la Silla observatory optical observations
- GRB 130418A: Bassano Bresciano Observatory optical observations
- GRB 130418A: Swift detection of a burst with an optical counterpart
- GRB 130408A: Suzaku WAM observation of the prompt emission
- GRB 130408a: Skynet Optical Observations
- GRB 130408A, Swift-BAT refined analysis
- GRB 130408A: Zadko observatory - Gingin optical observations
- GRB130408A: Swift/UVOT followup observations
- GRB 130408A: Swift-XRT refined Analysis
- Konus-Wind observation of GRB 130408A
- GRB 130408A - Gemini-S/GMOS redshift determination
- GRB 130408A - VLT/X-shooter redshift determination
- GRB 130408A: GROND detection of the afterglow
- GRB 130408A: Swift/UVOT Detection of the Optical Afterglow
- GRB 130408A: Liverpool Telescope Optical candidate detection
- GRB 130408A: Swift detection of a burst
- GRB 130211A: Retraction of afterglow candidate
- GRB 130327B: Suzaku WAM observation of the prompt emission
- Swift detection of IGR J18245-2452
- IPN Triangulation of GRB 130320B (very long/bright)
- Swift/XRT observation of GRB 130327B
- GRB 130327A: RATIR Optical/NIR afterglow confirmation
- GRB 130310A: RATIR Observations
- Swift Trigger 552142 is a noise event
- GRB 130327B: Fermi-LAT detection of a burst
- GRB 130327B: Fermi GBM detection
- Swift Trigger 552142: a possible GRB
- GRB 130327A: Swift-BAT refined analysis
- GRB 130327A: Swift-XRT refined Analysis
- GRB 130327A: Swift/UVOT Upper Limits
- GRB 130327A: RATIR Optical and NIR Observations
- 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
- GRB 130315A: GROND afterglow candidate
- GRB 130315A: Swift/UVOT Upper Limits
- GRB 130315A: SALT optical observations
- GRB 130315A: Swift-XRT refined Analysis
- GRB 130315A, Swift-BAT refined analysis
- GRB 130313A: Swift/UVOT Upper Limits
- GRB 130305A: PTF P48 optical upper limits
- GRB 130315A: Swift detection of a burst
- GRB 130310A : Suzaku WAM observation of the prompt emission
- GRB 130313A: RATIR Optical and NIR Observations
- Swift-BAT trigger 551030 is not astrophysical
- 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: Swift detection of a short burst
- IPN Triangulation of GRB 130307A
- GRB 130306A: Swift Detection of a Possible Afterglow
- GRB 130310A: Fermi GBM detection
- GRB 130310A: Fermi-LAT detection and localization
- GRB 130131A: JCMT SCUBA-2 sub-mm observations
- GRB 130306A: Swift-BAT refined analysis
- IPN triangulation of GRB 130228A
- GRB 130305A: Further Swift-XRT Observations
- Konus-Wind observation of GRB 130306A
- 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 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
- GRB 130216B: Suzaku WAM observation of the prompt emission
- 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