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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"

18074 results found.

  1. GRB010213 detected by HETE
  2. HETE Status
  3. Optical Observations of GRB 001018 at Keck
  4. Optical observations of GRB 001018 with JCAM
  5. IPN TRIANGULATION OF GRB010109
  6. IPN triangulation of GRB010104
  7. IPN triangulation of GRB010103
  8. IPN triangulation of GRB001219
  9. GRB 001212 Optical Observation
  10. GRB 001212 Optical Observation
  11. GRB001120, optical observations
  12. GRB 001109: deep JHK upper limits
  13. GRB 001109 X-ray afterglow with BeppoSAX
  14. CORRECTION to XMM-Newton observation of GRB001025
  15. GRB001109, Radio observations
  16. GRB001105 BVRI field photometry correction
  17. GRB001105, BVRI field photometry
  18. GRB 001025B, Optical obervations
  19. GRB 991208: HST Imaging of the Host Galaxy
  20. GRB 001025B, I-band observations
  21. GRB 001025A, optical observation
  22. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  23. GRB001007: Optical observations
  24. GRB001007, Radio observations
  25. IPN TRIANGULATION OF GRB001020
  26. CORRECTION TO PEAK FLUX OF GRB001018
  27. IPN TRIANGULATION OF GRB 001017
  28. V,R,I band observations of GRB000926
  29. GRB000926 - Amateur Optical Observations
  30. CONCAM null result on GRB001005
  31. GRB000926 - Optical observations
  32. GRB000926 - Optical observations
  33. GRB 000926, Optical Observations
  34. GRB000926 K'-band Observation
  35. J and K band observations of GRB 000926
  36. CONCAM crude optical limits before and after GRB000926
  37. GRB 000926: Optical candidate
  38. Optical candidate for GRB000926
  39. GRB 000911, BVRI field photometry
  40. GRB000911, Radio and Optical observations
  41. GRB000911: Optical observations
  42. False GRB alarm from RXTE/ASM on 8 Sept 2000
  43. GRB000830, BVRI field photometry
  44. GRB000830: Optical observations
  45. IPN localization of GRB000820
  46. IPN localization of GRB000812
  47. GRB000801, VLT-Antu R-band observations
  48. GRB 991208 Host Galaxy Imaging
  49. IPN localization of GRB000730B
  50. IPN localization of GRB000730B
  51. GRB 990510: Possible detection of a host galaxy
  52. GRB 990510 Host Galaxy Discovery
  53. GRB 990712: Late time HST/STIS Observations
  54. GRB 991216, HST/STIS observations
  55. GRB000630, optical observations
  56. GRB000630, Revised BVRI Field Photometry
  57. GRB000630, Optical Observations
  58. GRB000630, optical observations
  59. GRB000630, optical observations
  60. GRB000630, BVRI Field Photometry
  61. GRB000630, optical observations
  62. GRB000630, optical observations
  63. GRB000630: Optical observations
  64. possible optical counterpart of GRB 000630
  65. IPN triangulation of GRB000630
  66. GRB 000620, optical observations
  67. GRB000418, HST/STIS Observations
  68. GRB990123: Late-time HST/STIS observations of the host
  69. GRB000620, optical observations
  70. GRB000620 - Optical observations
  71. GRB000620 Optical observations
  72. GRB000620: BeppoSAX WFC and GRBM detection
  73. GRB000607, optical observations
  74. GRB 000615: NIR further observations
  75. GRB000616 optical observations
  76. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  77. GRB000615, further R-band photometry
  78. GRB 000615: NIR observations
  79. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  80. GRB000615, R-band photometry
  81. GRB 000301C: Further Late-Time HST/STIS observations
  82. GRB000528: follow-up X-ray measurements and update of IPN annulus
  83. BeppoSAX X-ray transient/possible GRB000608
  84. GRB000604 - Optical observations
  85. GRB000607, A SHORT, HARD BURST
  86. GRB000604, optical observations
  87. GRB000528, optical observations at ESO
  88. GRB 000418: Detection of the Host Galaxy
  89. GRB000604, optical observations, comparison with DPOSS
  90. GRB000528, Radio Observations
  91. X-ray Afterglow of GRB 000529
  92. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  93. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  94. GRB 000528 - WFC measurements
  95. GRB000519, BVRI field photometry
  96. GRB000508B, optical photometry
  97. GRB000508B, BVR field photometry
  98. Possible GRB-related phenomenon
  99. RXTE/ASM and IPN localization of GRB 000508B
  100. GRB000424, UBVRI field photometry

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