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"41700 results found.
- Swift Trigger 657564: MASTER-NET early optical observations.
- Swift Trigger 657564: XRT prompt analysis
- LIGO/Virgo G184098: MASTER OTs detection and Scenario Machine prediction
- Swift Trigger 657564: a probable GRB
- LIGO/Virgo G184098: Ongoing gravitational-wave analysis
- GRB 151001A: Swift-BAT refined analysis
- GRB 151001A: RATIR Observations
- GRB 151001B: Swift/UVOT Upper Limits
- GRB 151001B: Swift-XRT refined Analysis
- GRB 151001B: Swift-BAT refined analysis
- GRB 151001A: Swift/UVOT Detection
- GRB 151001B: MASTER-NET early optical observations.
- GRB 151001A: NOT imaging
- GRB 151001A: Swift-XRT refined Analysis
- GRB 151001A: Fermi GBM detection
- GRB 151001B: Swift detection of a burst
- GRB 151001A: Swift detection of a burst with an optical counterpart
- LIGO/Virgo G184098: spectral classification of PS15cci
- LIGO/Virgo G184098: Update to LT Spectroscopy of PS15ccx
- LIGO/Virgo G184098: Liverpool Telescope Spectroscopy of PS15ccx
- GRB 150925A: Swift/UVOT Upper Limits
- GRB 150925A: Swift-BAT refined analysis
- GRB 150925A: Swift-XRT refined Analysis
- GRB 150925A: Swift detection of a burst
- LIGO/Virgo G184098: LOFAR follow-up
- LIGO/Virgo G184098: ASKAP followup
- LIGO/Virgo G184098: ongoing Pan-STARRS search for optical transients
- LIGO/Virgo G184098: optical transient search with Kiso Schmidt telescope and KWFC on behalf of J-GEM collaboration
- Konus-Wind observation of GRB 150922A
- LIGO/VIRGO G184098 : classifications of transients from the LSQ observations
- GRB 150922A: Fermi GBM observation
- IPN Triangulation of GRB 150922A (short/hard)
- Konus-Wind observation of GRB 150919A
- IPN Triangulation of GRB 150919A (short / hard)
- LIGO/Virgo G184098: INTEGRAL search of temporally coincident prompt hard X-ray emission
- LIGO/Virgo G184098: transient search with VISTA
- ANTARES neutrino detection: Fermi GBM Observations
- Fermi GBM trigger bn150920977 is not due to a GRB
- LIGO/Virgo G184098: DESGW followup program
- LIGO/Virgo G184098: SkyMapper observations
- LIGO/Virgo G184098: TAROT network optical observations
- LIGO/Virgo G184098: La Silla - QUEST Followup
- LIGO/Virgo G184098: Swift follow-up observations
- LIGO/Virgo G184098: MWA Followup
- LIGO/Virgo G184098: DESGW followup program
- LIGO/Virgo G184098: Pan-STARRS1 observations of the northern sky region
- LIGO/Virgo observing run 1 (O1) starts 2015-09-18 15:00 UTC
- LIGO/Virgo G184098: Keck II DEIMOS Spectra of iPTF Optical Candidates
- LIGO/Virgo G184098: Nearby Galaxies in Error Circle
- LIGO/Virgo G184098: Fermi-GBM ground-based follow-up
- LIGO/Virgo G184098: Observations from the TOROS collaboration
- LIGO/Virgo G184098: iPTF Optical Transient Candidates
- LIGO/Virgo G184098: VST-ESO PARANAL observations
- LIGO/Virgo G184098: Pan-STARRS1 observations of the northern sky region
- Instructions for reporting follow-up observations related to LIGO/Virgo G184098
- LIGO/Virgo G184098: observations by MASTER
- LIGO/Virgo G184098: TAROT La Silla Observatory optical observations (TZAC)
- LIGO/Virgo G184098: Swift follow-up observations
- LIGO/Virgo G184098: Burst candidate in LIGO engineering run data
- GRB 150915A: Swift-XRT refined Analysis
- GRB 150915A, Swift-BAT refined analysis
- GRB 150910A: AAO optical observations
- Konus-Wind observation of GRB 150911A
- GRB150915A : IRSF NIR upper limits
- GRB 150915A: NOT observations of a brightening afterglow
- GRB 150915A: Swift UVOT upper limits
- GRB 150906B: Further analysis of the Konus-Wind data
- GRB 150910A: Mt. Terskol observatory optical observations
- GRB 150910A: TSHAO optical observations
- GRB 150915A: VLT/X-shooter redshift
- GRB 150915A: GROND detection of an optical counterpart candidate
- GRB 150915A: MASTER-NET optical observations
- GRB 150915A: Swift detection of a burst
- GRB 150910A: T100 observations
- GRB 150911A: GROND Upper Limits
- GRB 150910A: Continued RATIR Observations
- GRB 150907A: Swift-XRT afterglow detection
- GRB 150912A: Swift-XRT and UVOT observations
- GRB 150911A: Chuguev observatory upper limit
- GRB 150911A: Mt. Terskol observatory upper limit
- GRB 150911A: Khureltogot upper limit
- GRB 150910A: Mt. Terskol observatory optical observation
- Fermi GBM trigger 463890496/150914103 is not a GRB
- GRB 150912A: MITSuME Ishigakijima upper limits
- GRB 150911A: WHT optical imaging
- GRB 150910A: RATIR Observations
- GRB 150910A: MITSuME Ishigakijima Optical Observation after 2 days
- GRB 150912A: MASTER-IAC optical observations
- GRB 150912A: Fermi GBM observation
- GRB 150906B - NGC 3313 association: Constraints from Ep-Eiso and Ep-Liso Relations
- GRB 150912A: Swift ToO observations
- GRB 150906B: theoretical estimation of redshift and isotropic energy
- GRB150910A: P60 Observations
- GRB150911A: P60 Observations
- GRB 150911A: Swift/UVOT Upper Limits
- GRB 150911A: Swift-BAT refined analysis
- GRB 150912A: A long GRB detected by INTEGRAL
- GRB 150911A: Swift-XRT refined Analysis
- GRB 150910A: AAO optical observations
- GRB 150910A: MITSuME Ishigakijima Optical Observation after 1 day