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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').

3086 results found.

  1. XRF 030824: additional observations at CFHT
  2. IPN triangulation of GRB031007 (two large error boxes)
  3. IPN triangulation of GRB030922B (large error box)
  4. XRF030823 (=H2818): An X-Ray Flash Localized by the HETE WXM and SXC
  5. IPN triangulation of GRB030919 (large error box)
  6. GRB030913: AAVSO optical observations
  7. GRB 030824: Candidate Afterglow (or Variable/Flare Star?)
  8. IPN triangulation of GRB030714 (two large error boxes)
  9. IPN triangulation of GRB030626 (two large error boxes)
  10. GRB030429, refiend optical brightness
  11. GRB 030329: all-sky CCD images by K. Shiokawa immediately after the burst
  12. GRB030429: Optical Observations
  13. GRB 030329, the review of the sky area in plate archive (1950-1998)
  14. GRB030329: optical observations at Tokyo Tech
  15. GRB030329 - near contemporaneous optical limits from CONCAM
  16. IPN triangulation of GRB030325 (single small error box)
  17. IPN triangulation of GRB030325 (two small error boxes)
  18. IPN triangulation of GRB030320 (small error box)
  19. GRB 030227: Optical limit at RIKEN
  20. GRB 030228, optical observations
  21. GRB 030227: fading of candidate optical afterglow 'S1-A'
  22. GRB 030227, possible optical counterpart of XMM-Newton source
  23. GRB030227 - faint tentative OT candidate
  24. GRB 030227: Kyoto optical observation
  25. IPN triangulation of GRB030119 (two large error boxes)
  26. IPN triangulation of GRB030117 (two large error boxes)
  27. IPN triangulation of GRB021219 - CORRECTION
  28. GRB021219: a long GRB localized by INTEGRAL
  29. IPN triangulation of GRB021206 (small error box)
  30. GRB021104: Optical Observations
  31. IPN triangulation of GRB021020 (smaller error box)
  32. GRB021016(=H2397): A Long GRB Localized by HETE
  33. IPN triangulation of GRB021008 (two small error boxes)
  34. GRB 021004: Optical measurement at OHP
  35. GRB 021004: Optical Photometry at 2.5 Days
  36. GRB021004: Update Bisei photometric data
  37. IPN triangulation of GRB020914
  38. Confirmation of IPN error box for GRB020910
  39. IPN triangulation of GRB020910
  40. Single IPN error box for GRB020904
  41. IPN triangulation of GRB020904
  42. GRB 020812: optical observation at Kyoto University
  43. GRB020819(=H2275): A Long Burst Localized by the HETE WXM and SXC
  44. GRB020812: optical observations
  45. IPN triangulation of GRB020708
  46. IPN triangulation of GRB020708
  47. GRB 020705: Optical observations
  48. GRB 020603, R-band observation
  49. GRB020531: optical observations
  50. GRB 020409: Optical Observations
  51. GRB020124 optical observations with RIBOTS/RIMOTS
  52. GRB 020321: Candidate X-ray Counterparts
  53. GRB011212: Optical Observations
  54. GRB020127(=H1902): Localization of a Double-Peaked GRB by HETE
  55. GRB011212: Optical observations at Gunma
  56. GRB011130 (=XRF011130): Further analysis of Chandra Target of
  57. IPN triangulation of GRB011121
  58. GRB 010629 Optical Observations
  59. GRB 010222
  60. IPN/RXTE TRIANGULATION OF GRB010126
  61. GRB010126, TNG R-band observations
  62. GRB010126 optical observations
  63. IPN TRIANGULATION OF GRB010126
  64. IPN triangulation of GRB001219
  65. IPN triangulation of GRB000911
  66. IPN localization of GRB000820
  67. IPN localization of GRB000811
  68. GRB000607, A SHORT, HARD BURST
  69. GRB000424, optical observations
  70. IPN localization of GRB991226
  71. GRB 991106, LOTIS Optical Observations
  72. IPN/NFI error box for GRB991014
  73. IPN error box for GRB990915 (=BATSE 7766)
  74. GRB990806 UBVRIJHK observations
  75. GRB990704, optical observations
  76. IPN error box for GRB990527
  77. IPN localization for GRB990506
  78. GRB 990316, Optical observations
  79. GRB990308, Possible new SGR~0209+70
  80. GRB990123, early optical counterpart detection
  81. GRB 981226 Optical Observations
  82. GRB 981226 optical observations
  83. GRB980326 IPN annulus
  84. Untitled
  85. Untitled
  86. Untitled

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