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"15246 results found.
- GRB 151122A: Swift ToO observations
- Konus-Wind observation of GRB 151120A
- GRB 151120A: Fermi GBM observation
- LIGO/Virgo G194575: Updated significance from offline GW analysis
- GRB 151120A: Swift ToO observations
- GRB 151120A: A long GRB detected by INTEGRAL
- LIGO/Virgo G194575: Fermi GBM Observations
- GRB 151027A: SAO RAS and Mt. Terskol observations
- GRB 151114A: GROND Detection of the Optical/NIR Afterglow Candidate
- GRB 151111A: GROND confirmation of the afterglow and photometric redshift estimate
- GRB 151112A: GROND Detection of the Optical/NIR Afterglow Candidate
- GRB 151111A: GROND marginal detection of a afterglow candidate
- GRB 151111A: Fermi GBM observation
- LIGO/Virgo G194575: Liverpool Telescope observations of iPTF-15dld and iPTF-15dni
- LIGO/Virgo G194575: La Silla QUEST, Pan-STARRS and PESSTO observations of iPTF15dld
- GRB 151107B
- GRB 151107A, Swift-BAT refined analysis
- GRB 151027A: Hankasalmi optical observations
- LIGO/Virgo G194575: INAF-TNG/Asiago Telescope follow-up of iPTF15dld
- LIGO/Virgo G194575: INAF-Asiago Telescope further analysis of iPTF candidates
- LIGO/Virgo G194575: INAF-Asiago Telescope follow-up of iPTF candidates
- LIGO/Virgo G194575: VLA follow-up
- GRB 151027A: Mondy optical observations
- GRB 151027A: the missing GeV component
- GRB 151029A: FRAM optical afterglow detection
- GRB 151027A: Correction to GCN 18519
- GRB 151031A: GROND observation
- LIGO/Virgo G194575: LT Spectroscopy of iPTF candidates
- GRB 151031A
- GRB 151030A: Fermi GBM observation
- LIGO/Virgo G194575: INAF-TNG follow-up of iPTF15dkm and iPTF15dlj
- GRB 151029A: MITSuME Ishigakijima upper limits
- GRB 151027B: Swift UVOT detection
- LIGO/Virgo G194575: VLA follow-up
- GRB 151027A: NOT optical and NIR observations
- Konus-Wind observation of GRB 151027A
- GRB 151027B: RATIR Observations
- GRB 151027B: GROND Optical/NIR Afterglow Detection
- GRB 151027A: UVOT Observations
- GRB 151027A: Early RAPTOR Observations
- LIGO/Virgo G194575: MASTER Optical Inspection
- GRB 151027A: Fermi GBM observation
- GRB 151027A: MITSuME Akeno Optical observation
- LIGO/Virgo G194575: Swift observations of LSQ15bjb
- LIGO/Virgo G194575: INAF-TNG spectra of LSQ15bjb
- LIGO/Virgo G194575: GROND multi-color observations
- GRB 151027A: P60 afterglow confirmation and rebrightening
- GRB 151027A: KAIT optical afterglow confirmation
- LIGO/Virgo G194575: INAF-TNG follow-up of LSQ15bjb
- LIGO/Virgo G194575 : La Silla - QUEST followup
- GRB 151021A: Skynet PROMPT-CTIO/DSO17 observations of the optical afterglow
- GRB 151023A
- Possible Fermi-LAT Gamma-ray counterpart for LIGO/Virgo G194575
- LIGO/Virgo G194575: LOFAR follow-up
- LIGO/Virgo G194575: INTEGRAL search of temporally coincident prompt hard X-ray emission
- LIGO/Virgo G194575: more details on transients from Pan-STARRS in the RA=1hr localisation region
- LIGO/Virgo G194575: Fermi GBM Observations
- LIGO/Virgo G194575: Identification of a GW CBC Candidate
- GRB 151022A: Kanata/HOWPol optical observation
- GRB 151021B: Fermi GBM detection
- Konus-Wind observation of GRB 151021A
- GRB 151021A: MITSuME Okayama upper limits
- LIGO/Virgo G184098: LOFAR follow-up
- GRB 151004A: Swift-XRT follow-up observations
- Trigger 659734: Swift detection of SAX J1750.8-2900 or other source near Galactic center
- Konus-Wind observation of GRB 151006A
- GRB 151006A: Fermi-LAT detection
- Konus-Wind observation of GRB 151001B
- GRB 151006A: Kanata/HOWPol optical imaging polarimetry
- Trigger 657564 / GRB 151004A: Swift BAT and XRT refined analysis
- LIGO/Virgo G184098: ongoing Pan-STARRS search for optical transients
- GRB 151001A: Fermi GBM detection
- LIGO/Virgo G184098: Update to LT Spectroscopy of PS15ccx
- LIGO/Virgo G184098: Liverpool Telescope Spectroscopy of PS15ccx
- LIGO/Virgo G184098: LOFAR follow-up
- LIGO/Virgo G184098: ongoing Pan-STARRS search for optical transients
- Konus-Wind observation of GRB 150922A
- GRB 150922A: Fermi GBM observation
- Konus-Wind observation of GRB 150919A
- LIGO/Virgo G184098: INTEGRAL search of temporally coincident prompt hard X-ray emission
- ANTARES neutrino detection: Fermi GBM Observations
- LIGO/Virgo G184098: DESGW followup program
- LIGO/Virgo G184098: TAROT network optical observations
- LIGO/Virgo G184098: La Silla - QUEST Followup
- LIGO/Virgo G184098: Swift follow-up observations
- LIGO/Virgo G184098: DESGW followup program
- LIGO/Virgo G184098: Keck II DEIMOS Spectra of iPTF Optical Candidates
- LIGO/Virgo G184098: Fermi-GBM ground-based follow-up
- LIGO/Virgo G184098: Pan-STARRS1 observations of the northern sky region
- LIGO/Virgo G184098: TAROT La Silla Observatory optical observations (TZAC)
- Konus-Wind observation of GRB 150911A
- GRB150915A : IRSF NIR upper limits
- GRB 150915A: NOT observations of a brightening afterglow
- GRB 150906B: Further analysis of the Konus-Wind data
- GRB 150911A: GROND Upper Limits
- GRB 150907A: Swift-XRT afterglow detection
- GRB 150910A: MITSuME Ishigakijima Optical Observation after 2 days
- GRB 150912A: Fermi GBM observation
- GRB 150912A: Swift ToO observations
- GRB 150906B: theoretical estimation of redshift and isotropic energy