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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').
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"

31 results found.

  1. LIGO/Virgo S200114f: Gemini Spectra of AT 2020vu, AT 2020vw, AT 2020vy, and AT 2020vz
  2. LIGO/Virgo S200114f : No significant candidates in TAROT - FRAM - GRANDMA observations
  3. LIGO/Virgo S200114f: AstroSat CZTI upper limits
  4. LIGO/Virgo S200114f: Upper limits from Konus-Wind observations
  5. LIGO/Virgo S200114f: SOAR spectroscopy of AT2020zf, AT2020ace and AT2020ach
  6. LIGO/Virgo S200114f: More candidates from the Zwicky Transient Facility
  7. LIGO/Virgo S200114f: No transients found in J-GEM observations of nearby galaxies
  8. LIGO/Virgo S200114f: ZTF Forced Photometry of the Swift Source S200114f_X2
  9. LIGO/Virgo S200114f: Upper Limits from Wide-Field Infrared Search with Palomar Gattini-IR
  10. LIGO/Virgo S200114f: Possible X-ray transient
  11. LIGO/Virgo S200114f: Swift-XRT sources and observations
  12. LIGO/Virgo S200114f: No counterpart in targeted WHT/ACAM imaging
  13. LIGO/Virgo S200114f: AT2020vr, AT2020vt, AT2020wa and AT2020wc 10.4m GTC spectroscopy
  14. LIGO/Virgo S200114f: Upper limits from CALET observations.
  15. LIGO/Virgo S200114f: Candidates from SAGUARO observations
  16. LIGO/Virgo S200114f: No Counterparts in DDOTI/OAN Optical Observations
  17. LIGO/Virgo S200114f: Constraints on a CCSN origin from KM3NeT MeV neutrino search.
  18. LIGO/Virgo S200114f: SAGUARO previous detection of ZTF candidate ZTF20aafeaqk (AT2020vx)
  19. LIGO/Virgo S200114f: upper limits from AGILE-GRID observations
  20. LIGO/Virgo S200114f: no counterpart candidates in the Swift/BAT observations
  21. LIGO/Virgo S200114f: No counterpart candidates in Fermi-LAT observations
  22. LIGO/Virgo S200114f: not observable by AGILE at the event time
  23. LIGO/Virgo S200114f: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  24. LIGO/Virgo S200114f : no neutrino counterpart candidate in ANTARES search
  25. LIGO/Virgo S200114f: Candidates from the Zwicky Transient Facility
  26. LIGO/Virgo S200114f: Upper limits from Fermi-GBM Observations
  27. LIGO/Virgo S200114f: Coverage and upper limits from MAXI/GSC observations
  28. LIGO/Virgo S200114f: Identification of a GW unmodeled transient candidate
  29. LIGO/Virgo S200114f: No counterpart candidates in HAWC observations
  30. LIGO/Virgo S200114f: Upper limits from IceCube neutrino searches
  31. LIGO/Virgo S200114f: Global MASTER-Net observations report

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