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"28064 results found.
- GRB 071126: Enhanced Swift-XRT position
- VLA radio detection of GRB 071122
- GRB071122: Swift/UVOT Observations
- GRB071104: NIR Afterglow Candidate at TNG
- GRB 071122 Swift XRT position update sent in error.
- GRB 071122 Swift-XRT refined analysis
- GRB 071122: Corrected P60 Coordinates
- GRB071122: Gemini Absorption redshift
- GRB 071122: P60 Optical Afterglow Candidate
- GRB 071122: ROTSE-III Optical Limits
- GRB 071122: Swift detection of a burst
- GRB 071118: P60 Observations
- GRB071118 MITSuME OAO optical observation
- GRB 071118: Observations from OSN
- GRB 071117: VLT observations and probable redshift
- Swift/UVOT observations of GRB071118
- GRB 071117: Swift-XRT revised position
- Swift XRT follow-up observations of GRB071008
- Swift/UVOT upper limits for GRB 071117
- GRB071118: Swift XRT refined analysis
- GRB 071117: Gemini Optical Afterglow Discovery
- GRB 071117: TAROT La Silla observatory optical observations
- GRB 071118: Swift detection of a burst
- GRB 071117: Gemini Observations
- GRB 071117: Las Campanas optical observations
- GRB 071117: Swift-XRT refined analysis
- VLT FORS2 observations of short hard GRB071112B
- GRB 071117: Swift/XRT position
- GRB 071117: Initial Swift/UVOT observations
- GRB 071117: Swift detection of a bright burst
- Swift detection of MXB 0656-072
- VLA radio upper limit on GRB 071112C
- ATCA radio observations of short hard burst GRB 071112B
- Correction to the Swift-BAT Transient Identification (trigger=296683)
- GRB 071112C: WSRT Radio Observations
- GRB 071112C: optical observation
- GRB 071112C: optical observation
- GRB 071112C: emission lines and refined VLT redshift
- GRB 071112C: SARA upper limit
- GRB 071112C : Second Epoch Lulin R-band observations
- GRB071112C MITSuME Okayama Optical Observation
- GRB 071112C: Swift-BAT refined analysis
- GRB 071112C: Swift/UVOT observations
- GRB 071112C: Swift XRT refined analysis
- GRB 071112C: Optical observations at Crni Vrh
- GRB 071112C: VLT redshift
- GRB 071112B: Gemini Optical Imaging
- GRB 071112B: Swift-XRT preliminary analysis
- GRB071112C: NOT observations
- GRB 071112C: Palomar Pre-Imaging
- GRB 071112C : Lulin R-band observation
- Swift XRT follow-up observations of GRB071028B
- GRB071112C Xinglong_TNT_and_EST_afterglow observations
- GRB 071112C: Optical and NIR afterglows observed with KANATA
- GRB 071112C: Swift detection of a burst with an optical counterpart
- GRB 071112B: Swift detection of a short hard burst
- GRB 071112: Swift detection of a possible burst
- GRB071109: Super-LOTIS observations
- VLA IInd observation of INTEGRAL burst GRB 071109
- Swift/UVOT initial analysis of GRB071109
- GRB 071109: further Swift-XRT analysis
- No radio detection at Swift-XRT position
- GRB 071109: Swift-XRT possible X-ray counterpart
- VLA prompt radio detection of the INTEGRAL burst 071109
- GRB 071104: Swift-XRT Team Refined Analysis
- GRB 071104: Possible Swift UVOT Afterglow Candidate
- GRB 071104: Swift-XRT position
- GRB071010b: optical observation
- Swift XRT and UVOT observations of GRB071028B
- GRB 071101: Swift-XRT Team refined analysis
- GRB071101: Optical and NIR upper limits by KANATA
- GRB0711101: Two new source from Xinglong TNT observation
- GRB 071101: TAROT Calern observatory optical observations
- GRB 071101: Swift XRT position
- GRB 071101: a nearby galaxy
- GRB 071101: Swift detection of a burst
- GRB 071031: Swift/UVOT detection of afterglow
- GRB 071031: Swift-XRT Team refined analysis
- GRB 071020: MITSuME Akeno optical observations
- GRB 071031: REM NIR and Optical observation
- GRB 071031, SMARTS afterglow observations
- GRB 071031: VLT high-resolution spectroscopy
- GRB071031: Rapid PROMPT Detections
- GRB 071031: GROND detection in all bands
- GRB 071031: Swift detection of a burst with an optical counterpart
- GRB 071028B Swift-BAT detection of a burst
- GRB071025: Optical+NIR observations
- GRB 071028: SARA observations of variable source
- Swift UVOT upper limits to GRB071028
- GRB071028: Xinglong EST V-band upper limit
- GRB 071028: Swift-XRT Team refined analysis
- GRB 071028: Swift detection of a burst
- GRB 071025: Kuiper Telescope Optical Observations
- GRB 071003: Infrared Photometry with Keck Adaptive Optics
- GRB 071018: Revised BAT position
- GRB 071025: SARA VRI upper limits
- GRB 071025: SQIID JHK photometry
- GRB 071025A: Complex Early-Time IR Behavior, Simultaneous with Gamma- and X-rays
- Swift UVOT upper limits
- GRB071025: Xinglong TNT I-band upper limit