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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"

22060 results found.

  1. IPN triangulation of GRB000516
  2. Re: GRB000508B : Optical observations
  3. GRB000508B, optical photometry
  4. Possible GRB-related phenomenon
  5. GRB 000424 Optical Observations
  6. The redshift of GRB 000418
  7. GRB000424, optical observations
  8. IPN localization of GRB000429
  9. GRB 000418, optical observation
  10. GRB000424 Optical Observations
  11. GRB000424, optical observations
  12. GRB000424, optical observations
  13. GRB 000424, Optical Observations
  14. GRB 000418, Optical Observation
  15. GRB000418, near-infrared observations
  16. IPN error box for GRB000418
  17. GRB000419 [IPN Position]
  18. GRB000416 Optical Observations
  19. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  20. GRB000416 BRJK observations
  21. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  22. Budget cuts in BeppoSAX operations: impact on GRB observations
  23. GRB 000408, optical observations
  24. Refined IPN error box for GRB000408
  25. GRB000408: Optical CCD Observations from MIRO
  26. GRB000408, lotis optical observations
  27. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  28. GRB000408 [IPN Position]
  29. GRB000326 Optical Observations
  30. GRB000301C - R magnitude lower limit
  31. GRB000326, Further VLA observations
  32. GRB 000323, optical observations
  33. GRB 000326: Optical Observations
  34. GRB000326, Radio observations
  35. GRB000326 [IPN Position]
  36. GRB 000307 optical observations
  37. GRB000323 [IPN Position]
  38. GRB000315 [IPN Positions]
  39. GRB000313, Radio observations
  40. GRB 000313 - optical transient in the BATSE error box
  41. GRB 000307, Optical Observations
  42. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  43. GRB 000301C: HST/STIS CCD Imaging of the field
  44. IPN error box for GRB000307
  45. GRB 000301c: K' observations
  46. GRB000301C, optical R-band observations
  47. GRB000301c - R photometry and nearby faint source confirmation
  48. GRB 000301C, Optical Observation
  49. GRB 000301c: K' observations
  50. GRB 000301C Optical Observations
  51. GRB 000301C: K' Observations
  52. GRB000301C OT candidate optical observations
  53. GRB000301C - Host galaxy not detected in R (?)
  54. Optical observations of GRB000301c
  55. GRB000301C, Radio observations
  56. GRB000301C, Radio observations
  57. GRB000301C optical observations
  58. GRB000301C, near-infrared observations (JHK' imaging)
  59. GRB 000301c near-IR observations
  60. GRB000301C, optical observations
  61. GRB 000301C, Optical Observation
  62. GRB000301C, near-infrared observations (JHK' photometry)
  63. GRB000301c optical observations
  64. GRB 000301A, Radio Observations
  65. GRB000301C, optical observations
  66. GRB000301c, near-infrared observations
  67. Radio observations of the error box of GRB000301A
  68. GRB000301C: RXTE/ASM and IPN localizations
  69. GRB000301A [IPN Position]
  70. GRB000226 [IPN Position]
  71. HST Observations of GRB 990712
  72. GRB 000214 near-IR observations
  73. GRB 000115 Optical observations
  74. GRB 000214, Radio Observations
  75. GRB000210, Radio Observations
  76. Optical observations of GRB000210
  77. GRB 000210: BATSE Observations
  78. Optical observations of the Chandra X-ray source for GRB000210
  79. GRB000210, Radio Observations
  80. Optical candidate for GRB000210
  81. Chandra Observations of GRB000210 X-ray Afterglow
  82. GRB000201, Radio Observations
  83. Optical observations of GRB000131
  84. GRB000201 Optical Observations
  85. GRB 000201: TAROT optical observations
  86. GRB 000131 Optical Observations
  87. GRB000126 Optical Observations
  88. GRB 991208, radio observations
  89. BATSE+IPN location of GRB000131
  90. IPN localization of GRB000131
  91. GRB 000126, optical observations
  92. GRB000126, optical observations
  93. IPN localization of GRB000126
  94. GRB 000115 Optical observations
  95. BATSE Observations of GRB000115
  96. IPN annulus for GRB000115
  97. GRB991216, UBVRIJHK field photometry
  98. GRB991216 late optical observation
  99. Single IPN error box for GRB991229
  100. GRB 991216 VLBA Observations

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