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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').

23918 results found.

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

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