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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"

7398 results found.

  1. GRB010126 opt. obs.
  2. GRB010126 Optical Observations
  3. GRB 001204: Ks observations
  4. GRB 001212 possible OA in 2MASS
  5. GRB001204: Optical observations
  6. GRB001120: Gunn-i observations
  7. GRB001120: Optical observations
  8. GRB 001109: deep JHK upper limits
  9. GRB001007: Optical observations
  10. GRB001007, Radio observations
  11. GRB 001007, BVR-band observations
  12. GRB000911: VLT infrared observation
  13. GRB000911: optical VLT observations
  14. GRB000926 K'-band Observation
  15. J and K band observations of GRB 000926
  16. GRB000911 Optical Observations
  17. GRB 000926, optical observation by Oksanen (vsnet-grb)
  18. GRB000926: Optical observations
  19. GRB 000926, Optical Observation
  20. GRB000926, radio observations
  21. GRB 000926: Optical candidate
  22. Optical candidate for GRB000926
  23. GRB000911: Corrected coordinates
  24. GRB000911: Optical Transient
  25. GRB000911, Radio and Optical observations
  26. GRB000911: Optical observations
  27. GRB000830: Optical observations
  28. Chandra Position of GRB000210
  29. GRB000830: Optical observations
  30. HST/STIS observations of the host galaxy of GRB 980329
  31. GRB000630, Optical Observations
  32. GRB000630, optical observations
  33. GRB000630, optical observations
  34. GRB000630: Optical observations
  35. possible optical counterpart of GRB 000630
  36. GRB000604 - Optical observations
  37. GRB000604, optical observations
  38. X-ray Afterglow of GRB 000529
  39. GRB000529: Optical Observations
  40. GRB000519: Optical observations
  41. GRB 000528 Optical Observations
  42. GRB 000418, Optical observation
  43. GRB 000418, Optical Observation
  44. GRB 000418, optical observation
  45. GRB 000418, Optical Observation
  46. GRB 000418, Optical Observation
  47. GRB 000408, optical observations
  48. GRB000301C - R magnitude lower limit
  49. GRB 000307 optical observations
  50. GRB000301C - B and R photometry
  51. GRB000301C - R photometry
  52. GRB 000301c: K' observations
  53. GRB000301C, optical R-band observations
  54. GRB000301c - R photometry and nearby faint source confirmation
  55. GRB 000301c: K' observations
  56. GRB 000301C: K' Observations
  57. GRB000301C OT candidate optical observations
  58. GRB000301C - Host galaxy not detected in R (?)
  59. GRB000301C optical observations
  60. GRB 000301c near-IR observations
  61. GRB000301C, optical observations
  62. GRB000301C, near-infrared observations (JHK' photometry)
  63. GRB 000301C: OT confirmed
  64. GRB000301c optical observations
  65. GRB000301C, optical observations
  66. GRB 000301C : Optical Candidate
  67. GRB000214: X-ray afterglow candidate
  68. Optical candidate for GRB000210
  69. GRB 000115 Optical observations
  70. GRB 991216: J band spectrophotometry
  71. GRB 991208 Keck Spectroscopy
  72. GRB 991208 optical observations
  73. GRB 991208: Radio Observations
  74. GRB991106: BeppoSAX/BATSE results
  75. GRB 990510: optical observations
  76. GRB 990510: optical observations
  77. GRB981220 VLBA observations
  78. GRB 990316, Radio observations
  79. GRB 990316, Optical observations
  80. GRB990316, Optical observations
  81. GRB 990316 optical observations
  82. GRB 981220, radio observations
  83. GRB990123, Optical observation
  84. GRB990123 Optical Observation
  85. GRB 981226 Optical Observations
  86. GRB981226 Optical Observations
  87. GRB 981226 optical observations
  88. GRB980425 Optical Follow-up
  89. GRB 980703 H-band Observations
  90. SGR1900+14 field optical observations
  91. Reduced error box of SGR 1627-41
  92. GRB980613 Near Infra-Red Observations
  93. GRB980519 Optical Observations
  94. GRB980515, BeppoSAX IAUC to be submitted
  95. GRB 980425 Radio Light Curve
  96. GRB 980425 Brightness Temperature
  97. GRB980425: Radio Observations
  98. GRB 971214: KPNO Optical Observations

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