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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"

7396 results found.

  1. GRB 001204: Ks observations
  2. GRB 001212 possible OA in 2MASS
  3. GRB001204: Optical observations
  4. GRB001120: Gunn-i observations
  5. GRB001120: Optical observations
  6. GRB 001109: deep JHK upper limits
  7. GRB001007: Optical observations
  8. GRB001007, Radio observations
  9. GRB 001007, BVR-band observations
  10. GRB000911: VLT infrared observation
  11. GRB000911: optical VLT observations
  12. GRB000926 K'-band Observation
  13. J and K band observations of GRB 000926
  14. GRB000911 Optical Observations
  15. GRB 000926, optical observation by Oksanen (vsnet-grb)
  16. GRB000926: Optical observations
  17. GRB 000926, Optical Observation
  18. GRB000926, radio observations
  19. GRB 000926: Optical candidate
  20. Optical candidate for GRB000926
  21. GRB000911: Corrected coordinates
  22. GRB000911: Optical Transient
  23. GRB000911, Radio and Optical observations
  24. GRB000911: Optical observations
  25. GRB000830: Optical observations
  26. Chandra Position of GRB000210
  27. GRB000830: Optical observations
  28. HST/STIS observations of the host galaxy of GRB 980329
  29. GRB000630, Optical Observations
  30. GRB000630, optical observations
  31. GRB000630, optical observations
  32. GRB000630: Optical observations
  33. possible optical counterpart of GRB 000630
  34. GRB000604 - Optical observations
  35. GRB000604, optical observations
  36. X-ray Afterglow of GRB 000529
  37. GRB000529: Optical Observations
  38. GRB000519: Optical observations
  39. GRB 000528 Optical Observations
  40. GRB 000418, Optical observation
  41. GRB 000418, Optical Observation
  42. GRB 000418, optical observation
  43. GRB 000418, Optical Observation
  44. GRB 000418, Optical Observation
  45. GRB 000408, optical observations
  46. GRB000301C - R magnitude lower limit
  47. GRB 000307 optical observations
  48. GRB000301C - B and R photometry
  49. GRB000301C - R photometry
  50. GRB 000301c: K' observations
  51. GRB000301C, optical R-band observations
  52. GRB000301c - R photometry and nearby faint source confirmation
  53. GRB 000301c: K' observations
  54. GRB 000301C: K' Observations
  55. GRB000301C OT candidate optical observations
  56. GRB000301C - Host galaxy not detected in R (?)
  57. GRB000301C optical observations
  58. GRB 000301c near-IR observations
  59. GRB000301C, optical observations
  60. GRB000301C, near-infrared observations (JHK' photometry)
  61. GRB 000301C: OT confirmed
  62. GRB000301c optical observations
  63. GRB000301C, optical observations
  64. GRB 000301C : Optical Candidate
  65. GRB000214: X-ray afterglow candidate
  66. Optical candidate for GRB000210
  67. GRB 000115 Optical observations
  68. GRB 991216: J band spectrophotometry
  69. GRB 991208 Keck Spectroscopy
  70. GRB 991208 optical observations
  71. GRB 991208: Radio Observations
  72. GRB991106: BeppoSAX/BATSE results
  73. GRB 990510: optical observations
  74. GRB 990510: optical observations
  75. GRB981220 VLBA observations
  76. GRB 990316, Radio observations
  77. GRB 990316, Optical observations
  78. GRB990316, Optical observations
  79. GRB 990316 optical observations
  80. GRB 981220, radio observations
  81. GRB990123, Optical observation
  82. GRB990123 Optical Observation
  83. GRB 981226 Optical Observations
  84. GRB981226 Optical Observations
  85. GRB 981226 optical observations
  86. GRB980425 Optical Follow-up
  87. GRB 980703 H-band Observations
  88. SGR1900+14 field optical observations
  89. Reduced error box of SGR 1627-41
  90. GRB980613 Near Infra-Red Observations
  91. GRB980519 Optical Observations
  92. GRB980515, BeppoSAX IAUC to be submitted
  93. GRB 980425 Radio Light Curve
  94. GRB 980425 Brightness Temperature
  95. GRB980425: Radio Observations
  96. GRB 971214: KPNO Optical Observations

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