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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"

7408 results found.

  1. GRB010220, Optical Observations
  2. GRB 010220: Near-IR Observations
  3. GRB010214 follow-up from Hanle
  4. GRB 010222: Near-IR Observations
  5. GRB010214, candidate optical afterglow
  6. GRB 010214, Optical Observations
  7. GRB010213, Radio Observations
  8. GRB010214 Optical Observation
  9. GRB 010214, optical observations
  10. HETE Status
  11. GRB010126 opt. obs.
  12. GRB010126 Optical Observations
  13. GRB 001204: Ks observations
  14. GRB 001212 possible OA in 2MASS
  15. GRB001204: Optical observations
  16. GRB001120: Gunn-i observations
  17. GRB001120: Optical observations
  18. GRB 001109: deep JHK upper limits
  19. GRB001007: Optical observations
  20. GRB001007, Radio observations
  21. GRB 001007, BVR-band observations
  22. GRB000911: VLT infrared observation
  23. GRB000911: optical VLT observations
  24. GRB000926 K'-band Observation
  25. J and K band observations of GRB 000926
  26. GRB000911 Optical Observations
  27. GRB 000926, optical observation by Oksanen (vsnet-grb)
  28. GRB000926: Optical observations
  29. GRB 000926, Optical Observation
  30. GRB000926, radio observations
  31. GRB 000926: Optical candidate
  32. Optical candidate for GRB000926
  33. GRB000911: Corrected coordinates
  34. GRB000911: Optical Transient
  35. GRB000911, Radio and Optical observations
  36. GRB000911: Optical observations
  37. GRB000830: Optical observations
  38. Chandra Position of GRB000210
  39. GRB000830: Optical observations
  40. HST/STIS observations of the host galaxy of GRB 980329
  41. GRB000630, Optical Observations
  42. GRB000630, optical observations
  43. GRB000630, optical observations
  44. GRB000630: Optical observations
  45. possible optical counterpart of GRB 000630
  46. GRB000604 - Optical observations
  47. GRB000604, optical observations
  48. X-ray Afterglow of GRB 000529
  49. GRB000529: Optical Observations
  50. GRB000519: Optical observations
  51. GRB 000528 Optical Observations
  52. GRB 000418, Optical observation
  53. GRB 000418, Optical Observation
  54. GRB 000418, optical observation
  55. GRB 000418, Optical Observation
  56. GRB 000418, Optical Observation
  57. GRB 000408, optical observations
  58. GRB000301C - R magnitude lower limit
  59. GRB 000307 optical observations
  60. GRB000301C - B and R photometry
  61. GRB000301C - R photometry
  62. GRB 000301c: K' observations
  63. GRB000301C, optical R-band observations
  64. GRB000301c - R photometry and nearby faint source confirmation
  65. GRB 000301c: K' observations
  66. GRB 000301C: K' Observations
  67. GRB000301C OT candidate optical observations
  68. GRB000301C - Host galaxy not detected in R (?)
  69. GRB000301C optical observations
  70. GRB 000301c near-IR observations
  71. GRB000301C, optical observations
  72. GRB000301C, near-infrared observations (JHK' photometry)
  73. GRB 000301C: OT confirmed
  74. GRB000301c optical observations
  75. GRB000301C, optical observations
  76. GRB 000301C : Optical Candidate
  77. GRB000214: X-ray afterglow candidate
  78. Optical candidate for GRB000210
  79. GRB 000115 Optical observations
  80. GRB 991216: J band spectrophotometry
  81. GRB 991208 Keck Spectroscopy
  82. GRB 991208 optical observations
  83. GRB 991208: Radio Observations
  84. GRB991106: BeppoSAX/BATSE results
  85. GRB 990510: optical observations
  86. GRB 990510: optical observations
  87. GRB981220 VLBA observations
  88. GRB 990316, Radio observations
  89. GRB 990316, Optical observations
  90. GRB990316, Optical observations
  91. GRB 990316 optical observations
  92. GRB 981220, radio observations
  93. GRB990123, Optical observation
  94. GRB990123 Optical Observation
  95. GRB 981226 Optical Observations
  96. GRB981226 Optical Observations
  97. GRB 981226 optical observations
  98. GRB980425 Optical Follow-up
  99. GRB 980703 H-band Observations
  100. SGR1900+14 field optical observations

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