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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"

24658 results found.

  1. X-ray Afterglow of GRB 000529
  2. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  3. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  4. GRB 000528 - WFC measurements
  5. GRB000519, BVRI field photometry
  6. IPN triangulation of GRB000519
  7. GRB000508B, optical photometry
  8. GRB000508B, BVR field photometry
  9. Possible GRB-related phenomenon
  10. RXTE/ASM and IPN localization of GRB 000508B
  11. GRB000424, UBVRI field photometry
  12. GRB000418, UBVRI field photometry update
  13. GRB000424, optical observations
  14. GRB 000429, optical observation
  15. GRB 000429, UBVRI field photometry
  16. GRB 000418, UBVRI field photometry
  17. GRB 000418, optical observation
  18. GRB 000418, Optical Observation
  19. GRB000418, near-infrared observations
  20. Correction to IPN error box for GRB000419
  21. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  22. GRB000416 BRJK observations
  23. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  24. GRB 000408, optical observations
  25. GRB 991208, UBVRI field photometry
  26. GRB000408, lotis optical observations
  27. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  28. GRB000301C - Addendum to GCN 623
  29. GRB 000323, optical observations
  30. GRB 000326: Optical Observations
  31. GRB000326, Radio observations
  32. GRB000313, Radio observations
  33. GRB 000313 - optical transient in the BATSE error box
  34. GRB 000307, Optical Observations
  35. GRB 000307, BVRI Field Photometry
  36. GRB 000301C: A Precise Redshift Determination
  37. GRB 000301C, Optical Observation
  38. GRB 000301C: HST/STIS CCD Imaging of the field
  39. IPN error box for GRB000307
  40. GRB000301C, optical R-band observations
  41. GRB 000301C Optical Observations
  42. GRB 000301C: K' Observations
  43. GRB000301C OT candidate optical observations
  44. GRB000301C - Host galaxy not detected in R (?)
  45. Optical observations of GRB000301c
  46. GRB000301C, Radio observations
  47. GRB000301C, Radio observations
  48. GRB000301C, near-infrared observations (JHK' imaging)
  49. GRB 000301c near-IR observations
  50. GRB 000301C, UBVRI field photometry
  51. GRB 000301C: OT confirmed
  52. GRB000301c optical observations
  53. GRB000301C, optical observations
  54. GRB000301C
  55. GRB 000301C : Optical Candidate
  56. GRB000301C: RXTE/ASM and IPN localizations
  57. GRB000226 [IPN Position]
  58. HST Observations of GRB 990712
  59. GRB 000214 near-IR observations
  60. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  61. GRB000210, Radio Observations
  62. GRB 000115, BVRI field photometry
  63. GRB000214: BeppoSAX GRBM and WFC Detection
  64. Optical observations of GRB000210
  65. GRB000210 X-ray afterglow
  66. GRB000214: X-ray afterglow candidate
  67. GRB000214 refined BeppoSAX-WFC position
  68. GRB 000210: BATSE Observations
  69. Optical observations of the Chandra X-ray source for GRB000210
  70. GRB000210, Radio Observations
  71. IPN triangulation of GRB000210
  72. GRB000210: possible afterglow detection with BeppoSAX NFI
  73. GRB000201, Radio Observations
  74. GRB000210: BeppoSAX GRBM and WFC Detection
  75. SAX_WFC_GRB_NOTICE
  76. SAX_WFC_GRB_NOTICE
  77. GRB000201 Optical Observations
  78. GRB 000201: TAROT optical observations
  79. GRB 991208, radio observations
  80. BATSE+IPN location of GRB000131
  81. IPN localization of GRB000131
  82. GRB 000126, optical observations
  83. BATSE Observations of GRB000115
  84. Second RXTE Observation of GRB 000115
  85. GRB991216, UBVRIJHK field photometry
  86. GCN resumes full operations
  87. GRB 991216 VLBA Observations
  88. GRB 991216: J band spectrophotometry
  89. GRB 991216: Detection of the Host and/or Absorber Galaxy
  90. IPN localization of GRB991226
  91. GRB 991216 RXTE ASM Observations
  92. GRB 991216: Updated BATSE parameters
  93. GRB 991217 (SAX J2303.2+0015) Optical observations
  94. Chandra observation of the X-ray afterglow of GRB991216
  95. GRB 991216, optical observations
  96. GRB 991216 Optical spectroscopy/imaging
  97. SAX J2303.2+0015 Optical observations
  98. IR observations of GRB991216
  99. GRB 991217 (SAX J2303.2+0015) Optical observations
  100. GRB991216 Optical and infrared observations of Beethoven Burst

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