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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').

18687 results found.

  1. GRB010412: BeppoSAX GRBM and WFC observations
  2. GRB010324, revised field photometry
  3. REVISED LOCATION OF GRB010326A
  4. GRB 980326: Late-time HST/STIS observations
  5. GRB010324, field photometry
  6. GRB010326B, field photometry
  7. GRB010326, field photometry
  8. GRB010220, field photometry
  9. Further Optical Observations of GRB 010324
  10. GRB010222, CXO X-ray observations
  11. GRB010324, optical observations
  12. GRB010326B: Localization by HETE (2nd GRB for this date)
  13. GRB 010326 optical observations
  14. GRB010326: Refined Localization by HETE
  15. GRB010326: Localization by HETE
  16. Optical Observations of GRB 010324
  17. GRB010222, late-time optical observation
  18. Support extension to the BeppoSAX mission
  19. GRB 010222, Optical Observations
  20. GRB 010222: High-Resolution Keck Spectroscopy
  21. GRB010222 further R-band photometry
  22. GRB 010222: Keck Spectroscopy
  23. GRB010214, field photometry
  24. GRB010222, field photometry
  25. GRB010222 further R-band photometry
  26. GRB 010222 Kyoto optical observation
  27. GRB010222 R-BAND OBSERVATION
  28. GRB010214 follow-up from Hanle
  29. GRB 010222: Near-IR Observations
  30. GRB 010222: Optical Observations
  31. GRB010222, radio observations
  32. GRB010222, optical observations
  33. GRB010214B,Gamma Ray Observations
  34. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  35. GRB 010220, simultaneous optical observations
  36. GRB010220: BeppoSAX WFC and GRBM preliminary data
  37. GRB010214, optical observations
  38. GRB010214: BeppoSAX WFC and GRBM preliminary data
  39. GRB 010214: X-Ray afterglow
  40. GRB 010214 optical observation
  41. GRB010213, Radio Observations
  42. J-Band Observation of GRB 010214.
  43. GRB010214, Radio Observations
  44. GRB010213, Near-IR observations
  45. Possible InfraRed Transient of GRB 010214.
  46. GRB010213 (HETE) TAROT observations
  47. GRB010213 detected by HETE
  48. BeppoSAX ALERT: GRB010214
  49. HETE Status
  50. IPN/RXTE TRIANGULATION OF GRB010126
  51. GRB010126 optical observations
  52. IPN/RXTE TRIANGULATION OF GRB010126
  53. Optical Observations of GRB 001018 at Keck
  54. GRB010119, Radio observations
  55. Optical observations of GRB 001018 with JCAM
  56. IPN TRIANGULATION OF GRB010115
  57. IPN TRIANGULATION OF GRB010109
  58. IPN triangulation of GRB010103
  59. GRB 001204: Ks observations
  60. GRB 001212 Optical Observation
  61. GRB 001212 Optical Observation
  62. GRB001204, Radio observations
  63. IPN triangulation of GRB001204 (short/hard)
  64. GRB001120: Gunn-i observations
  65. GRB001120, optical observations
  66. WSRT 4.8 GHz observations of GRB001109
  67. IPN triangulation of GRB001120
  68. GRB 001109: deep JHK upper limits
  69. GRB 001109 X-ray afterglow with BeppoSAX
  70. CORRECTION to XMM-Newton observation of GRB001025
  71. GRB001109, Radio observations
  72. GRB001105 BVRI field photometry correction
  73. GRB001105, BVRI field photometry
  74. GRB 001025B, Optical obervations
  75. GRB 991208: HST Imaging of the Host Galaxy
  76. GRB 001025B, I-band observations
  77. GRB001025B, Radio observations
  78. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  79. IPN triangulation of GRB001025
  80. GRB001007: Optical observations
  81. ASM Localization of GRB 001025
  82. GRB001007, Radio observations
  83. IPN TRIANGULATION OF GRB001020
  84. GRB001018, Gamma Ray Observations
  85. V,R,I band observations of GRB000926
  86. The Likely Optical/Infrared Afterglow of GRB 001011
  87. HETE positions added to GCN
  88. BeppoSAX ALERT: GRB001011
  89. GRB000926 - Amateur Optical Observations
  90. CONCAM null result on GRB001005
  91. IPN triangulation of GRB001007
  92. IPN triangulation of GRB001005
  93. GRB 000926 Chandra Observation
  94. IPN triangulation of GRB 001004
  95. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  96. GRB000926 - Optical observations
  97. GRB000926 - Optical observations
  98. GRB 000926, Optical Observations
  99. GRB000926 K'-band Observation
  100. J and K band observations of GRB 000926

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