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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"

21795 results found.

  1. GRB 000418, Optical Observation
  2. Correction to IPN error box for GRB000419
  3. IPN error box for GRB000418
  4. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  5. GRB 000408, optical observations
  6. GRB 991208, UBVRI field photometry
  7. GRB000408, lotis optical observations
  8. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  9. GRB000408 [IPN Position]
  10. GRB000301C - Addendum to GCN 623
  11. GRB 000326: Optical Observations
  12. GRB000326, Radio observations
  13. GRB000315 [IPN Positions]
  14. GRB000313, Radio observations
  15. GRB 000313 - optical transient in the BATSE error box
  16. GRB 000307, BVRI Field Photometry
  17. GRB 000301C: HST/STIS CCD Imaging of the field
  18. IPN error box for GRB000307
  19. GRB000301C, optical R-band observations
  20. GRB000301c - R photometry and nearby faint source confirmation
  21. GRB 000301C Optical Observations
  22. GRB 000301C: K' Observations
  23. GRB000301C - Host galaxy not detected in R (?)
  24. Optical observations of GRB000301c
  25. GRB000301C, Radio observations
  26. GRB000301C, Radio observations
  27. GRB 000301c near-IR observations
  28. GRB 000301C, UBVRI field photometry
  29. GRB000301C, near-infrared observations (JHK' photometry)
  30. GRB 000301C: OT confirmed
  31. GRB000301c optical observations
  32. GRB000301c, near-infrared observations
  33. GRB000301C
  34. GRB 000301C : Optical Candidate
  35. GRB000301C: RXTE/ASM and IPN localizations
  36. GRB000226 [IPN Position]
  37. HST Observations of GRB 990712
  38. GRB 000214 near-IR observations
  39. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  40. GRB000210, Radio Observations
  41. GRB 000115, BVRI field photometry
  42. GRB000214: BeppoSAX GRBM and WFC Detection
  43. Optical observations of GRB000210
  44. GRB000210 X-ray afterglow
  45. GRB000214: X-ray afterglow candidate
  46. GRB000214 refined BeppoSAX-WFC position
  47. GRB 000210: BATSE Observations
  48. Optical observations of the Chandra X-ray source for GRB000210
  49. GRB000210, Radio Observations
  50. GRB000201, Radio Observations
  51. GRB000210: BeppoSAX GRBM and WFC Detection
  52. Optical observations of GRB000131
  53. GRB000201 Optical Observations
  54. GRB 000201: TAROT optical observations
  55. IPN localization of GRB000131
  56. GRB 000126, optical observations
  57. IPN localization of GRB000126
  58. BATSE Observations of GRB000115
  59. GRB991216, UBVRIJHK field photometry
  60. GCN resumes full operations
  61. IPN error boxes for GRB991229
  62. GRB 991216: Detection of the Host and/or Absorber Galaxy
  63. IPN error boxes for GRB991221
  64. IPN error box for GRB991216
  65. GRB 991217 (SAX J2303.2+0015) Optical observations
  66. Chandra observation of the X-ray afterglow of GRB991216
  67. GRB 991216, optical observations
  68. GRB 991216 Optical spectroscopy/imaging
  69. GRB991216 Optical and IR observations
  70. SAX J2303.2+0015 Optical observations
  71. IR observations of GRB991216
  72. GRB 991217 (SAX J2303.2+0015) Optical observations
  73. GRB991216 Optical and infrared observations of Beethoven Burst
  74. GRB 991216 Radio Observations
  75. GRB 991208 Infrared Detection
  76. GRB991216
  77. GRB 991216--Summary of RXTE Observations
  78. GRB 991216 Optical Observations
  79. GRB 991216, optical observations
  80. GRB 991208 SAO-RAS Spectroscopy
  81. SAX J2303.2+0015: an x-ray/GRB?
  82. GRB 991216, Optical Transient
  83. GRB991216 ('Beethoven Burst') B, R, and K Observations
  84. GRB991216, infrared observations
  85. GRB 991208 optical observations
  86. Lowell/Perkins observation of GRB 991216
  87. GRB 991216 Optical Observation
  88. GRB 991216: Extremely bright BATSE burst
  89. R-band Observations of GRB991208 at TNG
  90. GRB991208, optical observations
  91. GRB 991208, Optical Observation
  92. GRB991208, optical observations
  93. GRB 991208 Optical Decay
  94. Optical Observations of GRB991105
  95. GRB991106: BeppoSAX/BATSE results
  96. GRB 991106, optical observations
  97. BeppoSAX NFI Observation of GRB991106
  98. GRB 991106, radio observations
  99. GRB991106: the first BeppoSAX short GRB detection?
  100. GRB 991106 Optical Observations

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