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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.

Lucene Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

18 results found.

  1. ZTF20acozryr/AT2020yxz (GRB 201103B): Maidanak optical observations
  2. ZTF20acozryr/AT2020yxz (GRB 201103B): SAO RAS optical observations
  3. ZTF20acozryr/AT2020yxz (GRB 201103B): correction to the GCN #28883 CrAO/ZTSh optical observations
  4. ZTF20acozryr/AT2020yxz (GRB 201103B): CrAO/ZTSh optical observations
  5. ZTF20acozryr/AT2020yxz (GRB 201103B): Mondy continued optical observations
  6. ZTF20acozryr/AT2020yxz (GRB 201103B): Flattening of the optical light curve
  7. ZTF20acozryr (GRB 201103B): GROWTH-India Telescope optical observations
  8. ZTF20acozryr/AT2020yxz (GRB 201103B): Mondy, Kitab, TSHAO optical observations
  9. Konus-Wind observation of GRB 201103B
  10. GRB 201103B: GMG observation (2nd epoch)
  11. ZTF20acozryr/AT2020yxz (GRB 201103B): Assy optical observations
  12. Swift XRT and UVOT detection of ZTF20acozryr/AT2020yxz/GRB201103B
  13. GRB 201103B (ZTF20acozryr/AT2020yxz): Xinglong-2.16m optical observations
  14. Correcton to GCN 28848: Swift observes ZTF20acozryr
  15. GRB 201103B (ZTF20acozryr/AT2020yxz): VLT/X-shooter redshift
  16. GRB 201103B (ZTF20acozryr/AT2020yxz): Nanshan/NEXT-0.6m optical observations
  17. IPN triangulation of GRB 201103B (consistent with ZTF20acozryr/AT2020yxz)
  18. GRB 201103B: AGILE detection

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