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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"

16761 results found.

  1. GRB000604 - Optical observations
  2. GRB000604, optical observations
  3. GRB000528, optical observations at ESO
  4. GRB 000418: Detection of the Host Galaxy
  5. GRB000604, optical observations, comparison with DPOSS
  6. GRB000528, Radio Observations
  7. X-ray Afterglow of GRB 000529
  8. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  9. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  10. GRB 000528 - WFC measurements
  11. GRB000519, BVRI field photometry
  12. GRB000508B, optical photometry
  13. GRB000508B, BVR field photometry
  14. Possible GRB-related phenomenon
  15. RXTE/ASM and IPN localization of GRB 000508B
  16. GRB000424, UBVRI field photometry
  17. GRB000418, UBVRI field photometry update
  18. GRB000424, optical observations
  19. GRB 000429, optical observation
  20. GRB 000429, UBVRI field photometry
  21. GRB 000418, UBVRI field photometry
  22. GRB 000418, optical observation
  23. GRB 000418, Optical Observation
  24. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  25. GRB 000408, optical observations
  26. Refined IPN error box for GRB000408
  27. GRB 991208, UBVRI field photometry
  28. GRB000408: Optical CCD Observations from MIRO
  29. GRB000408, lotis optical observations
  30. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  31. GRB000408 [IPN Position]
  32. GRB000301C - Addendum to GCN 623
  33. GRB 000326: Optical Observations
  34. GRB000326, Radio observations
  35. GRB000313, Radio observations
  36. GRB 000313 - optical transient in the BATSE error box
  37. GRB 000307, BVRI Field Photometry
  38. GRB 000301C: HST/STIS CCD Imaging of the field
  39. GRB 000301C Optical Observations
  40. GRB 000301C: K' Observations
  41. GRB000301C - Host galaxy not detected in R (?)
  42. Optical observations of GRB000301c
  43. GRB000301C, Radio observations
  44. GRB000301C, Radio observations
  45. GRB 000301c near-IR observations
  46. GRB 000301C, UBVRI field photometry
  47. GRB 000301C: OT confirmed
  48. GRB000301c optical observations
  49. GRB000301C
  50. GRB 000301C : Optical Candidate
  51. HST Observations of GRB 990712
  52. GRB 000214 near-IR observations
  53. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  54. GRB000210, Radio Observations
  55. GRB 000115, BVRI field photometry
  56. GRB000214: BeppoSAX GRBM and WFC Detection
  57. Optical observations of GRB000210
  58. GRB000210 X-ray afterglow
  59. GRB000214: X-ray afterglow candidate
  60. GRB000214 refined BeppoSAX-WFC position
  61. Optical observations of the Chandra X-ray source for GRB000210
  62. GRB000210, Radio Observations
  63. GRB000201, Radio Observations
  64. GRB000210: BeppoSAX GRBM and WFC Detection
  65. GRB000201 Optical Observations
  66. GRB 000126, optical observations
  67. GRB991216, UBVRIJHK field photometry
  68. GCN resumes full operations
  69. GRB 991216: Detection of the Host and/or Absorber Galaxy
  70. IPN error box for GRB991216
  71. GRB 991217 (SAX J2303.2+0015) Optical observations
  72. Chandra observation of the X-ray afterglow of GRB991216
  73. SAX J2303.2+0015 Optical observations
  74. IR observations of GRB991216
  75. GRB 991217 (SAX J2303.2+0015) Optical observations
  76. GRB 991216 Radio Observations
  77. GRB 991208 Infrared Detection
  78. GRB991216
  79. GRB 991216--Summary of RXTE Observations
  80. GRB 991216 Optical Observations
  81. GRB 991216, optical observations
  82. GRB 991208 SAO-RAS Spectroscopy
  83. SAX J2303.2+0015: an x-ray/GRB?
  84. GRB 991216, Optical Transient
  85. GRB991216 ('Beethoven Burst') B, R, and K Observations
  86. GRB991216, infrared observations
  87. GRB 991208 optical observations
  88. GRB 991216 Optical Observation
  89. GRB 991216: Extremely bright BATSE burst
  90. GRB991208, optical observations
  91. GRB 991208, Optical Observation
  92. GRB991208, optical observations
  93. Optical Observations of GRB991105
  94. GRB991106: BeppoSAX/BATSE results
  95. BeppoSAX NFI Observation of GRB991106
  96. GRB 991106, radio observations
  97. GRB991106: the first BeppoSAX short GRB detection?
  98. GRB 991106 Optical Observations
  99. GRB991106, optical observation at SAO-RAS
  100. GRB 991106, LOTIS Optical Observations

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