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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').

15494 results found.

  1. GRB990123 Optical Observations
  2. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  3. GRB 990123: Continued Radio Observations
  4. GRB990123, Preliminary Lens Search Results
  5. Search for Potential Images of GRB 990123
  6. GRB990123, Optical BVRI Observations
  7. GRB 990123: near-infrared observations.
  8. GRB990123, OSSE observations
  9. GRB990123: NIR Observation
  10. "GRB 990123: New BV Observations"
  11. GRB 990123: New Optical Observations, Decay Measure
  12. GRB 990123 Optical Follow-Up
  13. GRB 990123: Possible Gravitationally Lensed Burst?
  14. GRB990123, optical observation
  15. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  16. GRB 990123 r-band photometry
  17. GRB 990123 Optical Follow-up
  18. Optical Observations of GRB 981220
  19. GRB 981226: radio variable
  20. GRB 981226 Optical Observations
  21. GRB981226 BeppoSAX follow up
  22. GRB 981226
  23. GRB 981226 optical observations
  24. GRB 981220:Optical Observations
  25. GRB981226, BeppoSAX Christmas GRB
  26. GRB 981226 optical observations
  27. GRB 981220, radio observations
  28. GRB 981220
  29. GRB 980326/Host Galaxy
  30. BeppoSAX NFI Observation of GRB980425
  31. GRB980329 R,I flux calibration and R,I,K upper limits
  32. GRB980425 Optical Follow-up
  33. GRB970508 optical observations
  34. GRB980519, Optical Observations
  35. GRB 980703 (NFI observations)
  36. GRB980703 optical photometry
  37. GRB980703 optical observations
  38. GRB980703: Radio transient
  39. GRB980703 Transient Optical Follow-Up
  40. GRB980703: LOTIS observation at early times
  41. BeppoSAX NFI observations of GRB 980703
  42. GRB980703 optical followup
  43. SGR1627-41
  44. Radio observations of SGRs
  45. SGR1900+14 field optical observations
  46. GRB 980613 Near-IR observations
  47. GRB 980613: Optical transient and its host galaxy
  48. SGR1627-41, Refined IPN annulus location
  49. GRB 980613: Detection of the probable host galaxy
  50. SGR 1627-41
  51. GRB 980613 Optical Observations
  52. GRB 980613 optical observations
  53. Discovery of a new SGR source, SGR1627-41
  54. GRB980613 Optical Observations
  55. GRB980613 observations from Palomar
  56. GRB980613 Near Infra-Red Observations
  57. GRB971214 Secondary Standards
  58. GRB980519 Secondary Standards
  59. GRB 980519 Optical Observations
  60. GRB 980519
  61. GRB980519 optical observations
  62. GRB 980519 Optical Observations
  63. GRB980519 Optical Observations
  64. GRB 980519 Optical Observations
  65. GRB980515, BeppoSAX IAUC to be submitted
  66. BSAX Observations of GRB980425 field
  67. SAX J0840.7+2248 Optical Observations
  68. GRB980425: optical obs.
  69. GRB980425: Radio Observations
  70. report on BSAX observations of GRB980425
  71. GRB980326 X-ray Observations
  72. GRB980326, optical observations
  73. GRB980326, optical observations
  74. GRB980326 IPN annulus
  75. GRB980329 Keck K-band observations
  76. GRB980326 optical observations
  77. GRB980329 optical observations
  78. GRB980329 VLA observations
  79. GRB980329 optical observations
  80. GRB980326 optical observations
  81. Untitled
  82. Untitled
  83. Untitled
  84. Untitled
  85. Untitled
  86. Untitled
  87. Untitled
  88. Untitled
  89. Untitled
  90. Untitled
  91. GRB 971214: Optical Observations
  92. Radio Observations of GRB 971214 at the VLA
  93. GRB 971024: KPNO Optical Observations
  94. GRB 970828: Palomar Observations

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