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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"

42737 results found.

  1. GRB000301c, near-infrared observations
  2. GRB000301C
  3. GRB 000301C : Optical Candidate
  4. GRB000301C: RXTE/ASM and IPN localizations
  5. GRB000301A [IPN Position]
  6. GRB000226 [IPN Position]
  7. HST Observations of GRB 990712
  8. GRB 000214 near-IR observations
  9. GRB 000115 Optical observations
  10. GRB 000214, Radio Observations
  11. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  12. GRB000210, Radio Observations
  13. Correction to GCN 557 (GRB000214: BeppoSAX GRBM and WFC Detection)
  14. GRB 000115, BVRI field photometry
  15. GRB000214: BeppoSAX GRBM and WFC Detection
  16. IPN annulus for GRB000214
  17. Optical observations of GRB000210
  18. GRB000210 X-ray afterglow
  19. BeppoSAX GRB000214 ("S. Valentine's day GRB")
  20. GRB 000210: BATSE Observations
  21. Correction to Chandra Position of GRB000210 afterglow
  22. GRB000210, Radio Observations
  23. Chandra Observations of GRB000210 X-ray Afterglow
  24. IPN triangulation of GRB000210
  25. GRB000210: possible afterglow detection with BeppoSAX NFI
  26. GRB000201, Radio Observations
  27. GRB000210: BeppoSAX GRBM and WFC Detection
  28. Optical observations of GRB000131
  29. GRB000201 Optical Observations
  30. GRB 000201: TAROT optical observations
  31. GRB 000131 Optical Observations
  32. GRB000126 Optical Observations
  33. GRB 991208, radio observations
  34. BATSE+IPN location of GRB000131
  35. IPN localization of GRB000131
  36. GRB 000126, optical observations
  37. GRB000126, optical observations
  38. IPN localization of GRB000126
  39. GRB 000115 Optical observations
  40. BATSE Observations of GRB000115
  41. IPN annulus for GRB000115
  42. Second RXTE Observation of GRB 000115
  43. GRB991216, UBVRIJHK field photometry
  44. GRB991216 late optical observation
  45. Single IPN error box for GRB991229
  46. GCN resumes full operations
  47. GRB 991216 VLBA Observations
  48. BEPPOSAX GRBM Localization of GRB991226
  49. IPN error boxes for GRB991229
  50. GRB 991216: J band spectrophotometry
  51. GRB 991216: Detection of the Host and/or Absorber Galaxy
  52. IPN localization of GRB991226
  53. Single IPN error box for GRB991221
  54. IPN error boxes for GRB991221
  55. GRB 991216 RXTE ASM Observations
  56. IPN error box for GRB991216
  57. Lowell/Perkins observation of GRB 991216
  58. GRB 991217 (SAX J2303.2+0015) Optical observations
  59. GRB991217/SAX J2303.2+0015, optical observations
  60. Chandra observation of the X-ray afterglow of GRB991216
  61. GRB 991216, optical observations
  62. GRB 991216 Optical Observations
  63. GRB 991216 Optical spectroscopy/imaging
  64. VLT spectra of GRB991216
  65. GRB991216 Optical and IR observations
  66. K observations of GRB991216
  67. IR observations of GRB991216
  68. GRB991216 radio observations
  69. GRB 991217 (SAX J2303.2+0015) Optical observations
  70. GRB991216 radio observations
  71. GRB991216 Spectroscopy
  72. Lowell/Perkins observation of GRB 991216
  73. GRB991216, optical observations
  74. GRB991216 Optical and infrared observations of Beethoven Burst
  75. Refined IPN localization of GRB991216
  76. GRB 991216 Radio Observations
  77. GRB 991208 Keck Spectroscopy
  78. GRB 991208 Infrared Detection
  79. GRB991216
  80. GRB 991216--Summary of RXTE Observations
  81. GRB 991216 Optical Observations
  82. GRB 991216, optical observations
  83. GRB 991208 SAO-RAS Spectroscopy
  84. SAX J2303.2+0015: an x-ray/GRB?
  85. GRB 991216, Optical Transient
  86. GRB 991216, Optical Afterglow
  87. GRB991216 ('Beethoven Burst') B, R, and K Observations
  88. GRB 991216: Comparison with DPOSS images
  89. GRB991216, infrared observations
  90. GRB991216 Optical Observations
  91. GRB 991208 optical observations
  92. Lowell/Perkins observation of GRB 991216
  93. GRB 991216 Optical Observation
  94. GRB 991208 Keck Spectroscopy
  95. GRB 991216: Extremely bright BATSE burst
  96. R-band Observations of GRB991208 at TNG
  97. GRB991208, optical observations
  98. GRB 991208 Keck Spectroscopy
  99. GRB991208 - millimeter detection
  100. GRB 991208, Optical Observation

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