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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"

19857 results found.

  1. GRB010222, field photometry
  2. GRB010222 further R-band photometry
  3. GRB010222, possible increase of optical decay slope
  4. GRB 010222 Kyoto optical observation
  5. GRB 010222 BV optical observations
  6. GRB010222 R-BAND OBSERVATION
  7. GRB010214 follow-up from Hanle
  8. GRB 010222: Near-IR Observations
  9. GRB 010222: Optical Observations
  10. GRB010222, radio observations
  11. GRB010222, optical observations
  12. GRB010220, Radio and Optical Observations
  13. GRB 010220, simultaneous optical observations
  14. GRB010220: BeppoSAX WFC and GRBM preliminary data
  15. GRB010214, optical observations
  16. BeppoSAX GRB010220: refined position
  17. GRB010214: BeppoSAX WFC and GRBM preliminary data
  18. GRB 010214: X-Ray afterglow
  19. GRB 010214 optical observation
  20. J-Band Observation of GRB 010214.
  21. GRB010213, Near-IR observations
  22. Possible InfraRed Transient of GRB 010214.
  23. GRB010213 (HETE) TAROT observations
  24. GRB010213 detected by HETE
  25. IPN Status Report
  26. HETE Status
  27. GRB010126 Optical Observations
  28. IPN TRIANGULATION OF GRB010126
  29. Optical Observations of GRB 001018 at Keck
  30. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  31. Optical observations of GRB 001018 with JCAM
  32. IPN TRIANGULATION OF GRB010115
  33. IPN TRIANGULATION OF GRB010109
  34. IPN TRIANGULATION OF GRB010109
  35. IPN triangulation of GRB010104
  36. IPN triangulation of GRB010103
  37. IPN triangulation of GRB001219
  38. GRB 001212 Optical Observation
  39. GRB 001212 Optical Observation
  40. GRB 001212 possible OA
  41. IPN triangulation of GRB001212
  42. Confirmation of IPN position for GRB001204
  43. IPN triangulation of GRB001204 (short/hard)
  44. GRB001120, optical observations
  45. WSRT 4.8 GHz observations of GRB001109
  46. IPN triangulation of GRB001120
  47. GRB 001109: deep JHK upper limits
  48. GRB 001109 X-ray afterglow with BeppoSAX
  49. CORRECTION to XMM-Newton observation of GRB001025
  50. GRB001109, Radio observations
  51. BeppoSAX ALERT: GRB001109
  52. GRB001105 BVRI field photometry correction
  53. GRB001105, BVRI field photometry
  54. IPN TRIANGULATION OF GRB001105
  55. GRB 001025B, Optical obervations
  56. GRB 991208: HST Imaging of the Host Galaxy
  57. GRB 001025B, I-band observations
  58. XMM-Newton observation of GRB001025
  59. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  60. GRB001007: Optical observations
  61. ASM Localization of GRB 001025
  62. GRB001007, Radio observations
  63. IPN TRIANGULATION OF GRB001019
  64. IPN TRIANGULATION OF GRB001018
  65. IPN TRIANGULATION OF GRB 001017
  66. V,R,I band observations of GRB000926
  67. HETE positions added to GCN
  68. GRB 001007, BVR-band observations
  69. GRB000926 - Amateur Optical Observations
  70. CONCAM null result on GRB001005
  71. IPN triangulation of GRB001007
  72. GRB000926 - Optical observations
  73. GRB000926 - Optical observations
  74. GRB 000926, Optical Observations
  75. GRB000926 K'-band Observation
  76. J and K band observations of GRB 000926
  77. GRB000911 Optical Observations
  78. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  79. CONCAM crude optical limits before and after GRB000926
  80. GRB 000926: Optical candidate
  81. Optical candidate for GRB000926
  82. IPN triangulation of GRB000926
  83. GRB 000911, BVRI field photometry
  84. GRB000911, Radio and Optical observations
  85. GRB000911: Optical observations
  86. IPN triangulation of GRB000910
  87. GRB000830, BVRI field photometry
  88. GRB000801, VLT-Antu R-band observations
  89. GRB000301C, UBVI optical observations
  90. GRB000801, Radio Observations
  91. GRB 991208 Host Galaxy Imaging
  92. IPN localization of GRB000730B
  93. IPN localization of GRB000730B
  94. GRB 990510: Possible detection of a host galaxy
  95. GRB 990510 Host Galaxy Discovery
  96. GRB 990712: Late time HST/STIS Observations
  97. GRB 991216, HST/STIS observations
  98. GRB000630, optical observations
  99. GRB000630, Revised BVRI Field Photometry
  100. GRB000630, Optical Observations

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