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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"

19570 results found.

  1. IPN TRIANGULATION OF GRB010109
  2. IPN triangulation of GRB010104
  3. IPN triangulation of GRB010103
  4. IPN triangulation of GRB001219
  5. GRB 001212 Optical Observation
  6. GRB 001212 Optical Observation
  7. GRB001120, optical observations
  8. GRB 001109: deep JHK upper limits
  9. GRB 001109 X-ray afterglow with BeppoSAX
  10. CORRECTION to XMM-Newton observation of GRB001025
  11. GRB001109, Radio observations
  12. GRB001105 BVRI field photometry correction
  13. GRB001105, BVRI field photometry
  14. GRB 001025B, Optical obervations
  15. GRB 991208: HST Imaging of the Host Galaxy
  16. GRB 001025B, I-band observations
  17. GRB 001025A, optical observation
  18. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  19. GRB001007: Optical observations
  20. GRB001007, Radio observations
  21. IPN TRIANGULATION OF GRB001020
  22. CORRECTION TO PEAK FLUX OF GRB001018
  23. IPN TRIANGULATION OF GRB 001017
  24. V,R,I band observations of GRB000926
  25. GRB000926 - Amateur Optical Observations
  26. CONCAM null result on GRB001005
  27. GRB000926 - Optical observations
  28. GRB000926 - Optical observations
  29. GRB 000926, Optical Observations
  30. GRB000926 K'-band Observation
  31. J and K band observations of GRB 000926
  32. CONCAM crude optical limits before and after GRB000926
  33. GRB 000926: Optical candidate
  34. Optical candidate for GRB000926
  35. GRB 000911, BVRI field photometry
  36. GRB000911, Radio and Optical observations
  37. GRB000911: Optical observations
  38. False GRB alarm from RXTE/ASM on 8 Sept 2000
  39. GRB000830, BVRI field photometry
  40. GRB000830: Optical observations
  41. IPN localization of GRB000820
  42. IPN localization of GRB000812
  43. GRB000801, VLT-Antu R-band observations
  44. GRB 991208 Host Galaxy Imaging
  45. IPN localization of GRB000730B
  46. IPN localization of GRB000730B
  47. GRB 990510: Possible detection of a host galaxy
  48. GRB 990510 Host Galaxy Discovery
  49. GRB 990712: Late time HST/STIS Observations
  50. GRB 991216, HST/STIS observations
  51. GRB000630, optical observations
  52. GRB000630, Revised BVRI Field Photometry
  53. GRB000630, Optical Observations
  54. GRB000630, optical observations
  55. GRB000630, optical observations
  56. GRB000630, BVRI Field Photometry
  57. GRB000630, optical observations
  58. GRB000630, optical observations
  59. GRB000630: Optical observations
  60. possible optical counterpart of GRB 000630
  61. IPN triangulation of GRB000630
  62. GRB 000620, optical observations
  63. GRB000418, HST/STIS Observations
  64. GRB990123: Late-time HST/STIS observations of the host
  65. GRB000620, optical observations
  66. GRB000620 - Optical observations
  67. GRB000620 Optical observations
  68. GRB000620: BeppoSAX WFC and GRBM detection
  69. GRB000607, optical observations
  70. GRB 000615: NIR further observations
  71. GRB000616 optical observations
  72. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  73. GRB000615, further R-band photometry
  74. GRB 000615: NIR observations
  75. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  76. GRB000615, R-band photometry
  77. GRB 000301C: Further Late-Time HST/STIS observations
  78. GRB000528: follow-up X-ray measurements and update of IPN annulus
  79. BeppoSAX X-ray transient/possible GRB000608
  80. GRB000604 - Optical observations
  81. GRB000607, A SHORT, HARD BURST
  82. GRB000604, optical observations
  83. GRB000528, optical observations at ESO
  84. GRB 000418: Detection of the Host Galaxy
  85. GRB000604, optical observations, comparison with DPOSS
  86. GRB000528, Radio Observations
  87. X-ray Afterglow of GRB 000529
  88. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  89. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  90. GRB 000528 - WFC measurements
  91. GRB000519, BVRI field photometry
  92. GRB000508B, optical photometry
  93. GRB000508B, BVR field photometry
  94. Possible GRB-related phenomenon
  95. RXTE/ASM and IPN localization of GRB 000508B
  96. GRB000424, UBVRI field photometry
  97. GRB000418, UBVRI field photometry update
  98. GRB000424, optical observations
  99. GRB 000429, optical observation
  100. GRB 000429, UBVRI field photometry

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