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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"

63 results found.

  1. GRB 250520A: Swift/UVOT Upper Limits
  2. GRB 231214A: Swift-XRT refined Analysis
  3. LIGO/Virgo/KAGRA S231114n: Updated Sky localization
  4. Fermi GRB 220330A: Global MASTER-Net observations report
  5. GRB 210905A: Swift/UVOT Upper Limits
  6. Fermi trigger No 645857659: Global MASTER-Net observations report
  7. GRB 210104A: AstroSat CZTI detection
  8. GRB 190919B: GROND detection of the NIR afterglow
  9. Fermi GRB190508.81 Global MASTER-Net observations report
  10. Konus-Wind observation of GRB 180703A
  11. GRB 180402A: Swift/UVOT Upper Limits
  12. Trigger 813449: Swift detection of large burst from XTE J1701-407
  13. GRB 171102B: Swift/UVOT Upper Limits
  14. GRB 160629A: TAROT Calern observatory optical detection
  15. Swift-BAT trigger 686845 was due to noise near a known source
  16. GRB 160506A: Swift/UVOT Upper Limits
  17. GRB 160314A: Swift/UVOT Detection
  18. GRB 160127A: TAROT La Silla observatory optical light curve
  19. Swift trigger 637807 is probably not an astrophysical source
  20. GRB 150317A: Swift/UVOT Upper Limits
  21. Konus-Wind observation of GRB 141229A
  22. GRB 140930B: Swift/UVOT Upper Limits
  23. Trigger 538084: Swift detection of XTE J1739-302
  24. GRB 111215A: Swift-XRT refined Analysis
  25. Swift J1822.3-1606: Transient Magnetar or Be X-ray Binary?
  26. GRB 110709A: Suzaku WAM observation of the prompt emission
  27. GRB 101213A: Swift-XRT refined Analysis
  28. IBAS Alert n. 6057 is not due to a GRB
  29. Trigger 424161: Swift/BAT trigger on XTE J1946+274/GRO J1944+26
  30. IBAS Alert 5992 is not a GRB, but XTE J1855-026
  31. Swift/BAT Detects an Outburst from XTE J1901+014
  32. Swift Trigger #382159 is due to XTE J1752-223
  33. Swift-BAT trigger 373691 is a galactic bulge transient
  34. GRB 091010: RXTE detection
  35. GRB 090621B: MAGIC telescope GeV observation
  36. Swift UVOT observations of GRB081028
  37. Swift detection of XTE J1701-407
  38. Trigger 317205: Swift detection of an outburst from XTE J1701-407
  39. GRB080426: Swift/UVOT upper limits
  40. GRB080319B: Time-Independent XRT Spectrum
  41. A giant outburst from Cygnus X-1 detected by Konus-Wind and Suzaku-WAM
  42. OT20050728 was not an optical GRB afterglow
  43. An interactive program for GRB pseudo-redshift computations
  44. IPN observations of SGR1806-20
  45. Correction to GCN Circ 3476 on GRB050525A
  46. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  47. GRB 050525: pseudo-redshift
  48. GRB 031026 (=H2882): Evidence for High Redshift from Prompt
  49. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  50. IPN detection of continued activity from SGR1806-20
  51. XRF 030824: observations at CFHT
  52. RXTE PCA Observations of SGR1806-20 Region
  53. Detection of activity from SGR 1900+14 with the RXTE/PCA
  54. RXTE Observations of SGR 1900+14
  55. The X-ray Flash 011030 ('GRB 011030')
  56. SGR 1900+14 : RXTE observations
  57. Further Optical Observations of GRB 010324
  58. Optical Observations of GRB 010324
  59. GCN resumes full operations
  60. Chandra observation of the X-ray afterglow of GRB991216
  61. GRB 990506: Limits on the possible optical transient
  62. GRB990308 (Trig. 7457), optical observations
  63. GRB 980703: BATSE Observations

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