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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').

22420 results found.

  1. GRB990123 Optical Observations
  2. GRB 990123: New Optical Observations, Decay Measure
  3. GRB 990123 Optical Follow-Up
  4. GRB 990123: Possible Gravitationally Lensed Burst?
  5. GRB990123, optical observation
  6. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  7. GRB990123, Optical observation
  8. GRB 990123: Optical Decay Slope
  9. GRB 990123 r-band photometry
  10. GRB 990123 Optical Follow-up
  11. GRB990123, early optical counterpart detection
  12. GRB990123 Optical Observation
  13. Possible identification of SN1999E with GRB980910
  14. Optical Observations of GRB 981220
  15. GRB 981226: radio variable
  16. GRB981220
  17. GRB981220, Correction to GCN 179
  18. GRB 981220 Optical observations
  19. GRB 981226 Optical Observations
  20. GRB 981220 and GRB 981226, optical observations
  21. GRB981226 Optical Observations
  22. GRB981226 BeppoSAX follow up
  23. GRB 981226
  24. GRB 981226 optical observations
  25. GRB981220 B, R and I band observations
  26. Optical Observations of GRB981226
  27. GRB 981220:Optical Observations
  28. GRB 981226 optical observations
  29. GRB 981220
  30. GRB 981220, radio observations
  31. GRB981220 I-band Observations
  32. GRB 981220
  33. GRB 980326/Host Galaxy
  34. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  35. BeppoSAX NFI Observation of GRB980425
  36. GRB980329 R,I flux calibration and R,I,K upper limits
  37. GRB980425 Optical Follow-up
  38. GRB 980923 BATSE Observations
  39. SGR1900+14, BeppoSAX-GRBM observations
  40. GRB970508 optical observations
  41. GRB971214, association with a Galactic star?
  42. GRB980519, Optical Observations
  43. GRB980703 - BeppoSAX/GRBM detection
  44. GRB980703 optical photometry
  45. GRB 980703: BATSE Observations
  46. GRB980703 optical observations
  47. GRB980703: Radio transient
  48. GRB 980703: Spectrum of the proposed optical counterpart
  49. GRB980703 Transient Optical Follow-Up
  50. GRB980703: LOTIS observation at early times
  51. GRB980613 Optical Observations
  52. GRB980703 (I band observations)
  53. BeppoSAX NFI observations of GRB 980703
  54. GRB980519 observation report
  55. GRB980703 optical followup
  56. Radio observations of SGRs
  57. SGR1900+14 field optical observations
  58. GRB980613, optical observations
  59. GRB 980613: Optical transient and its host galaxy
  60. SGR1627-41, RXTE/ASM observations
  61. GRB 980613: Detection of the probable host galaxy
  62. Reduced error box of SGR 1627-41
  63. GRB 980613: BATSE Observations
  64. GRB 980613 Optical Observations
  65. GRB 980613 optical observations
  66. Discovery of a new SGR source, SGR1627-41
  67. GRB980613 Optical Observations
  68. GRB980613 observations from Palomar
  69. GRB 980613 optical/IR obs.
  70. GRB980613 Near Infra-Red Observations
  71. GRB971214 Secondary Standards
  72. GRB980519 Secondary Standards
  73. BATSE on-board GRB trigger change
  74. GRB 980519 Optical Observations
  75. GRB 980519
  76. GRB980519 optical observations
  77. GRB 980519 Optical Observations
  78. GRB980519 BATSE Observations
  79. GRB980519 Optical Observations
  80. GRB980519 Optical Observations
  81. GRB 980519 Optical Observations
  82. GRB980515, BeppoSAX IAUC to be submitted
  83. BSAX Observations of GRB980425 field
  84. IPN web site of GRBs
  85. GRB980425 BATSE observations
  86. SAX J0840.7+2248 Optical Observations
  87. GRB980425: optical obs.
  88. GRB980425: Radio Observations
  89. report on BSAX observations of GRB980425
  90. GRB 980329 ROSAT observation
  91. GRB980326 X-ray Observations
  92. GRB980326, optical observations
  93. GRB980326, optical observations
  94. GRB980329, Fading IR counterpart to radio source
  95. GRB980329 Keck K-band observations
  96. GRB980329 sub-millimeter observations
  97. GRB980329 optical observations
  98. GRB980329 near-IR observations
  99. GRB980329 near-IR observations
  100. GRB980326 optical observations

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