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.
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"19549 results found.
- GRB 180115A: Swift detection of a burst with an optical counterpart.
- GRB 180111A: AbAO optical observations
- GRB 180113A: KAIT Optical Observations
- GRB 180111A: Swift/UVOT Detection
- GRB 180103A: Swift-XRT afterglow detection
- GRB 180111A: RATIR Optical and NIR Observations
- GRB 180111A: Enhanced Swift-XRT position
- GRB 180111A: Swift detection of a burst with an optical counterpart
- GRB 180103A: LCO Sutherland 1-m telescope observations
- GRB 180103A: Swift/UVOT Upper Limits
- GRB 180103A: Swift ToO observations
- GRB 180102A AROMA-N optical observation
- GRB 180102A: TSHAO optical upper limit
- GRB 180102A: Swift-BAT refined analysis
- GRB 180102A: Swift/UVOT Upper Limits
- GRB 180102A: NOT optical observations
- GRB 180102A: Enhanced Swift-XRT position
- GRB 180102A: Swift detection of a burst
- GRB 171222A: AROMA-N optical observation
- GRB 171222A: Nanshan-0.36m optical upper limit
- GRB 171222A: Swift/UVOT Upper Limits
- GRB 171222A: Nanshan-1m optical afterglow detection
- GRB 171205A: SMARTS optical/IR supernova monitoring
- GRB 171222A: Enhanced Swift-XRT position
- GRB 171222A: Swift detection of a burst
- GRB 171216A: Swift/UVOT Upper Limits
- GRB 171205A: RATAN observations
- GRB 171216A: Enhanced Swift-XRT position
- GRB 171216A: Swift detection of a burst
- Swift Trigger 797070 is probably not a GRB
- GRB 171212A: Swift-XRT refined Analysis
- GRB 171211A iTelescope observation
- GRB 171212A/Swift J1935.7+2036: Swift/UVOT Upper Limits
- GRB 171212A/Swift J1935.7+2036: TSHAO optical observations
- GRB 171212A: Enhanced Swift-XRT position
- GRB 171212A: Swift detection of a burst or a Galactic transient
- GRB 171211A: Swift-XRT refined Analysis
- GRB 171211A: Swift/UVOT Upper Limits
- GRB 171211A: Enhanced Swift-XRT position
- GRB 171210A: Swift-XRT and UVOT observations
- GRB 171211A: Swift detection of a possibly short burst
- GRB 171210A: Swift ToO observations
- GRB 171209A: Lulin 1m telescope observations
- GRB 171205A: iTelescope optical observations
- GRB 171205A: Mondy optical observations
- GRB 171205A: SAO-RAS optical observations
- GRB 171209A: Swift/UVOT Analysis of the burst
- GRB 171209A: Swift-XRT refined Analysis
- GRB 171209A: Enhanced Swift-XRT position
- Swift Trigger 796115 is probably not a GRB
- GRB 171205A: UKIRT near-IR observations
- GRB 171209A: Swift detection of a burst
- LIGO/Virgo G298048: Brightening X-ray Emission from GW170817/GRB170817A/SSS17a
- GRB 171205A: TSHAO optical observations
- LIGO/Virgo GW170817: Chandra X-ray brightening of the counterpart 108 days since merger
- LIGO/Virgo G298048: Late-time detection of the X-ray afterglow with Chandra
- GRB 171205A: GROND observations of the optical/NIR transient
- GRB 171205A: GMG observations (2nd night)
- GRB 171205A: Host galaxy photometric properties
- GRB 171205A: CHILESCOPE optical observations
- GRB 171205A: SMARTS optical/IR afterglow observations
- Possible blackbody component in the X-ray spectrum of GRB171205A
- GRB 171205A: GOTO detection of the optical counterpart
- GRB 171205A: TNG NIR detections
- GRB 171205A: LSGT optical afterglow follow-up observation
- GRB 171205A: GMG observation
- GRB 171205A: RATIR Optical and NIR Observations
- GRB 171205A: Swift/UVOT Detection
- GRB 171205A: Enhanced Swift-XRT position
- GRB 171205A: Swift detection of a burst
- GRB 171124A: TShAO optical observations
- GRB 171124A: Swift-XRT afterglow detection
- Pan-STARRS follow-up of IceCube-171106A
- LIGO/Virgo G299232: LOFAR follow-up
- GRB 171123A: TShAO optical upper limit
- GRB 171123A: OSN Upper Limit
- GRB 171123A: Tautenburg observations
- GRB 171123A: Nanshan-1m optical upper limit
- GRB 171123A: RATIR Optical and NIR Observations
- GRB 171123A: Swift/UVOT Upper Limits
- GRB 171123A: GMG observation limit
- GRB 171124A: Swift ToO observations
- GRB 171123A: Confirmation of the X-ray afterglow
- GRB 171123A: Enhanced Swift-XRT position
- GRB 171123A: Swift detection of a burst
- GRB 171120A: Xinglong-2.16m optical upper limit
- GRB 171120A: Swift/UVOT Upper Limits
- GRB 171120A: Enhanced Swift-XRT position
- GRB 171120A: Swift detection of a burst
- Fermi-LAT Gamma-ray Observations of IceCube-171106A
- GRB 171115A: RATIR Optical and NIR Observations
- GRB 171115A: Enhanced Swift-XRT position
- GRB 171115A: Swift detection of a burst
- IPN Triangulation of GRB 171108A (short)
- IceCube-171106A: Swift Observations
- HAWC follow-up of IceCube-171106A
- GRB 171010A: afterglow and SN 2017htp optical observations
- GRB 171108A: Fermi GBM detection
- INTEGRAL observation of IceCube-171106A
- GRB 171010A: possible SN component