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"27392 results found.
- GRB 070220 Swift-BAT Refined Analysis
- Swift/UVOT refined analysis of GRB070220
- GRB 070209: Swift XRT refined analysis
- GRB 070220: Swift-XRT Refined Analysis
- GRB 070220: Observation with the KANATA 1.5m telescope
- GRB 070219: Gemini Observations
- GRB 070220: Swift detection of a burst
- GRB070219: MASTER-VWF-Kislovodsk observations
- GRB 070219: Swift/UVOT Upper limits
- GRB 070219: I-band observations
- GRB 070219, Swift-BAT refined analysis
- GRB 070219: optical TNG observations
- GRB070219 - SDSS Pre-Burst Observations
- GRB 070219: Swift detection of a burst
- GRB 070125 observations with the GMRT
- GRB 070209: Redshift of a galaxy in the error circle of XRT source
- GRB 070129: MDM I-band Detection
- GRB 070125: Break in Optical Decay
- GRB 070209: Swift XRT analysis
- GRB 070201: clarification on localization and Konus-Wind spectra
- IPN localization of very bright long hard GRB 070207
- GRB 070209, Swift-BAT refined analysis of the short hard burst
- GRB 070208: Swift XRT refined analysis
- GRB 070208, Swift-BAT refined analysis
- GRB070208 - SDSS Pre-Burst Observations
- GRB 070208: Early IR detection and afterglow astrometry
- GRB 070208: Swift detection of a burst
- GRB 070125 detection with CARMA
- GRB 070125: Redshift z>~1.54 from Gemini Afterglow Spectrum
- GRB 070129: afterglow confirmation
- GRB070126: Swift-XRT Observation
- GRB 070129: Swift/UVOT Upper limits
- GRB 070125: optical observation
- GRB 070129, Swift-BAT refined analysis of a particularly long
- GRB 070129: Xinglong TNT optical Upper Limit
- GRB 070129: Swift-XRT Refined Analysis
- GRB 070129: VLT observations
- GRB 070125: An IR Point Source and an Apparent Host Galaxy
- GRB 070129: Swift detection of a burst
- GRB 070126: Swift/UVOT refined analysis
- GRB 070125: MITSuME Okayama optical observation
- GRB 070125: optical observations
- GRB 070126: VLT observations
- GRB 070124: Suzaku WAM observation of the prompt emissions
- GRB 070125: UVOT Detection in Ultraviolet Filters
- GRB 070126, Swift-BAT refined analysis of a very faint burst
- GRB070125: Optical observation by Kanata
- GRB070124: Swift-XRT Observation
- Possible GRB 070126: Swift/UVOT Upper Limit
- GRB 070125: UVOT Observations of a Fading Optical Afterglow
- GRB 070125: Xinglong TNT optical observations
- GRB 070125: Keck/LRIS Spectroscopy -- Evidence for a very low redshift
- GRB 070125: Lick 3m Spectroscopy
- GRB070125: Swift-XRT Refined Analysis
- GRB 070125: SARA detection in R
- GRB 070125: P60 Optical Afterglow Candidate
- GRB 070126?: Swift detection of a possible burst
- GRB070125 redshift request
- IPN localization of GRB070124 (short duration, hard spectrum)
- GRB 070110: Ep,i - Eiso correlation
- GRB 070107: Suzaku WAM observation of the prompt emission
- GRB070110: Swift XRT Team refined analysis
- GRB 070110, Swift-BAT refined analysis
- GRB070107 Swift/UVOT Observations of a Fading Optical Afterglow
- GRB 070110: Swift detection of a burst with a possible optical afterglow
- GRB 070107: Possible UVOT Afterglow
- GRB 070107, Swift-BAT refined analysis
- GRB 070107: Swift detection of a burst
- VLA observation of GRB 061222B
- VLA detection of GRB 061222A
- GRB070103: APO SPIcam i' and z' limits
- GRB070103: KPNO 4m+FLAMINGOS J limit
- GRB 070103: Swift/UVOT Upper limits
- GRB070103: Swift XRT refined analysis
- GRB 070103, Swift-BAT refined analysis
- GRB 070103: NOT observations
- GRB 070103: TAROT Calern observatory optical observations
- Retractions of previous Swift-BAT triggers
- erratum : SDSS Pre-burst Observations of GRB061126
- GRB 061210: Swift/XRT Astrometry Correction
- GRB 050826: MDM Redshift
- GRB 061222A: Confirmation of Gemini Afterglow Candidate
- GRB 061222A: Xinglong Optical Limit
- GRB 061222A: Gemini Afterglow Candidate
- GRB 061222B, Swift-BAT refined analysis
- GRB061222A Swift/UVOT: Upper Limits
- GRB 061222B: Swift/UVOT Upper limits
- GRB 061222B: Observation with the KANATA 1.5m telescope
- GRB 061222A: Observation with the KANATA 1.5m telescope
- GRB 061222B: BOOTES-IR optical observations
- GRB 061222B: SARA upper limit
- GRB 061217: Magellan host galaxy redshift
- GRB 061222A, Swift-BAT refined analysis
- GRB 061222B: REM NIR/optical observations
- GRB 061222B: TAROT La Silla observatory optical observations
- GRB 061222B: Swift detection of a burst
- GRB 061222b: optical afterglow
- GRB 061222A: Prompt ROTSE-III Optical Limits
- GRB 061222: Swift detection of a burst
- GRB 061218: TAROT La Silla observatory optical observations