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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"

27403 results found.

  1. GRB010214 follow-up from Hanle
  2. GRB 010222: Near-IR Observations
  3. GRB 010222: Optical Observations
  4. GRB010222: Optical decay slope
  5. GRB 010214, Optical Observations
  6. GRB010222, radio observations
  7. GRB010222, optical observations
  8. GRB010222: BeppoSAX/NFI Observations
  9. GRB010214B,Gamma Ray Observations
  10. GRB 010220, simultaneous optical observations
  11. GRB010220: BeppoSAX WFC and GRBM preliminary data
  12. GRB010214, candidate optical afterglow
  13. GRB010214, optical observations
  14. GRB010214: BeppoSAX WFC and GRBM preliminary data
  15. GRB 010214: X-Ray afterglow
  16. GRB 010214 optical observation
  17. GRB010213, Radio Observations
  18. J-Band Observation of GRB 010214.
  19. GRB010213, Near-IR observations
  20. Possible InfraRed Transient of GRB 010214.
  21. GRB 010214, optical observations
  22. GRB010213 detected by HETE
  23. IPN Status Report
  24. HETE Status
  25. IPN/RXTE TRIANGULATION OF GRB010126
  26. GRB010126 Optical Observations
  27. IPN TRIANGULATION OF GRB010126
  28. Optical Observations of GRB 001018 at Keck
  29. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  30. Optical observations of GRB 001018 with JCAM
  31. IPN TRIANGULATION OF GRB010115
  32. IPN TRIANGULATION OF GRB010109
  33. IPN TRIANGULATION OF GRB010109
  34. IPN triangulation of GRB010104
  35. IPN triangulation of GRB010103
  36. H band observation of GRB 001212
  37. IPN triangulation of GRB001219
  38. GRB 001212 Optical Observation
  39. GRB 001212 Optical Observation
  40. GRB 001212 possible OA in 2MASS
  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. GRB001105 BVRI field photometry correction
  52. GRB001105, BVRI field photometry
  53. IPN TRIANGULATION OF GRB001105
  54. GRB 001025B, Optical obervations
  55. GRB 991208: HST Imaging of the Host Galaxy
  56. GRB 001025B, I-band observations
  57. XMM-Newton observation of GRB001025
  58. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  59. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
  60. GRB001007: Optical observations
  61. ASM Localization of GRB 001025
  62. GRB001007, Radio observations
  63. GRB 001018, Possible Radio Afterglow
  64. GRB001018, Gamma Ray Observations
  65. IPN TRIANGULATION OF GRB001019
  66. IPN TRIANGULATION OF GRB001018
  67. IPN TRIANGULATION OF GRB 001017
  68. V,R,I band observations of GRB000926
  69. HETE positions added to GCN
  70. GRB000926 - Amateur Optical Observations
  71. CONCAM null result on GRB001005
  72. IPN triangulation of GRB001005
  73. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  74. GRB000926 - Optical observations
  75. GRB000926 - Optical observations
  76. GRB 000926, Optical Decay
  77. GRB000911: VLT infrared observation
  78. GRB 000926, Optical Observations
  79. GRB000926 K'-band Observation
  80. J and K band observations of GRB 000926
  81. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  82. CONCAM crude optical limits before and after GRB000926
  83. GRB 000926: Preliminary R-band Lightcurve
  84. Spectroscopic Redshift of GRB 000926
  85. GRB 000926: Optical candidate
  86. Optical candidate for GRB000926
  87. GRB 000911, BVRI field photometry
  88. GRB000911, Radio and Optical observations
  89. GRB000911: Optical observations
  90. GRB000830, BVRI field photometry
  91. GRB000210, Optical observations
  92. "Snapshot" afterglow IDs and GRB 000830
  93. GRB000730, Gamma Ray Observations
  94. GRB000812, Radio observations
  95. GRB000801, Gamma Ray Observations
  96. GRB000801, VLT-Antu R-band observations
  97. GRB 991208 Host Galaxy Imaging
  98. IPN localization of GRB000730B
  99. GRB 990510: Possible detection of a host galaxy
  100. GRB 990510 Host Galaxy Discovery

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