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"23442 results found.
- GRB 110402A: optical observations in Mondy
- GRB 110402A afterglow observation
- GRB 110402A: MITSuME Okayama and Ishigakijima Optical upper limits
- GRB 110328A/Swift J164449.3+573451: SARA-N detection
- GRB 110402A: Swift/UVOT detection of afterglow candidate
- GRB 110402A: Konkoly observations
- GRB 110328A: Konkoly observations.
- GRB 110402A: early optical limit by "Pi of the Sky"
- GRB 110402A: further NOT observations
- GRB110328A/Swift J164449.3+573451: Fermi LAT Observations
- GRB 110402A: PAIRITEL NIR Upper Limits
- GRB 110402A: Enhanced Swift-XRT position
- GRB 110402A: NOT afterglow confirmation
- GRB 110402A: Swift detection of a burst
- GRB 110328A / Swift J164449.3+573451: Radio-optical/NIR Astrometry
- GRB 110328A / Swift J164449.3+573451: Mondy optical observations
- GRB 110328/Swift J164449.3+573451: Fermi observations
- GRB 110328A / Swift J164449.3+573451: KASINICS K-band Observation
- GRB 110328A / Swift J164449.3+573451: X-ray analysis and a mini-blazar analogy
- GRB 110328A / Swift J164449.3+573451: PAIRITEL NIR Detection in 2nd Epoch
- GRB 110328A / Swift J164449.3+573451: No optical variability of the optical counterpart
- GRB 110328A / Swift J164449.3+573451: Konkoly observations
- GRB 110328A / Swift J164449.3+573451: LOAO R-band Observation
- GRB 110328A / Swift J164449.3+573451: PAIRITEL NIR Upper Limits
- GRB 110328A / Swift J164449.3+573451: optical observations
- GRB 110328A / Swift J164449.3+573451: optical spectroscopy from GTC
- GRB 110328B: Fermi GBM detection
- GRB 110328A / Swift J164449.3+573451: NOT optical observations.
- GRB / X-ray transient 110328A: MITSuME OkayamaOptical upper limits
- GRB 110328A / Swift J164449.3+573451: PTF Quiescent Optical Counterpart
- GRB 110328A: Enhanced Swift-XRT position
- GRB 110328A: Swift detection of a burst
- GRB110318B : MOA optical upper limit
- GRB 110319B Swift-XRT afterglow confirmation
- GRB 110319B BAT refined analysis
- GRB 110319B: Swift/UVOT Upper Limits
- GRB 110318B: Swift/UVOT Upper Limits
- GRB 110319B: GROND upper limits
- GRB 110319B: Swift-XRT afterglow candidate.
- GRB 110319B found in ground analysis of Swift-BAT data
- GRB 110319A: Swift/UVOT Detection
- GRB 110318B: GROND upper limits
- GRB 110319A: Enhanced Swift-XRT position
- GRB 110319A: Swift detection of a burst
- GRB 110318B: Enhanced Swift-XRT position
- GRB 110318B: Swift/UVOT Non-Detection of an Afterglow
- GRB 110318B: Swift detection of a burst
- GRB 110318A: Swift detection of a burst
- GRB 110315A: RTT150 optical observations
- GRB 110315A: Swift/UVOT Upper Limits
- GRB 110315A: Swift-BAT refined analysis
- GRB 110315A: Enhanced Swift-XRT position
- GRB 110315A: MASTER early optical observations
- GRB 110315A: Swift detection of a burst
- GRB110312A: MITSuME Okayama Optical upper limits
- GRB 110312A: RTT150 optical observations
- GRB 110312A: Swift/UVOT Upper Limits
- GRB 110312A: GROND Upper Limits
- GRB 110312A: Enhanced Swift-XRT position
- GRB 110312A: Swift detection of a burst
- GRB 110305A: REM detection of a possible NIR afterglow
- GRB110305A: MITSuME Ishigakijima Optical upper limits
- GRB 110305A: Swift/UVOT Upper Limits
- GRB 110305A: Enhanced Swift-XRT position
- GRB 110305A: GROND Detection of Optical Afterglow
- GRB 110305A: Swift detection of a burst
- GRB 110223A: optical upper limits
- GRB 110301A: Fermi GBM detection
- GRB101225A: early EVLA Observations of Christmas Burst
- Swift/UVOT observations of GRB110223A
- No IPN GRB detected in conjunction with candidate GRB 110215
- IBAS distribution of coordinates for low significance INTEGRAL GRB triggers
- Swift/UVOT observations of GRB110223b
- GRB 110223A : early optical limit by "Pi of the Sky"
- GRB 110223A: Enhanced Swift-XRT position
- GRB 110223B: Enhanced Swift-XRT position
- GRB 110223B: GROND Detection of Optical Afterglow Candidate
- GRB 110223A: Observations from BOOTES-2
- GRB 110223B: Swift detection of a burst
- GRB 110223A: Swift detection of a burst
- OT 110215: Further NIR observations from NOT of the GRB candidate
- GRB 110213B: Swift/UVOT observations
- Fermi GBM detection of an SGR-like burst
- Swift XRT and UVOT Observations of OT 110215
- OT 110215: NIR observations from NOT of GRB candidate
- GRB 110213A: optical observations in CrAO
- GRB 110213B: GROND observations of the optical/NIR afterglow
- OT 110215: possible GRB from 2MASS J00264184+8324093
- Swift/UVOT observations of GRB110210a.
- GRB 110210A: optical upper limit
- GRB 110213B: Possible Host Galaxy in SDSS Stripe 82 Imaging
- GRB 110210A: ROVOR Upper Limit
- GRB 110213B: P60 Optical Afterglow Candidate
- GRB110213A: RAPTOR Early Optical Peak and Plateau Measurements
- GRB 110212A: Swift XRT and UVOT observations
- GRB 110205A: Konkoly optical observations
- GRB 110213B: Swift XRT observation
- GRB 110213A: MITSuME Akeno Optical Observation
- Konus-Wind observation of GRB 110213B
- GRB110213A: MITSuME Okayama Optical Observation