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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').

16007 results found.

  1. GRB 990123 Optical Follow-Up
  2. GRB 990123: Possible Gravitationally Lensed Burst?
  3. GRB990123, optical observation
  4. GRB 990123 optical observations
  5. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  6. GRB990123 optical observations
  7. GRB 990123 r-band photometry
  8. GRB 990123 Optical Follow-up
  9. GRB990123 Optical Observation
  10. Possible identification of SN1999E with GRB980910
  11. Optical Observations of GRB 981220
  12. GRB 981226: radio variable
  13. GRB 981226 Optical Observations
  14. GRB981226 Optical Observations
  15. GRB981226 BeppoSAX follow up
  16. GRB 981226 radio observations
  17. GRB 981226
  18. GRB 981226 optical observations
  19. radio observations of GRB 981226
  20. GRB981220 B, R and I band observations
  21. GRB 981220:Optical Observations
  22. GRB 981226 optical observations
  23. GRB 981220, radio observations
  24. GRB 981220, radio observations
  25. GRB 981220
  26. GRB 980326/Host Galaxy
  27. GRB981220 IPN error box
  28. BeppoSAX NFI Observation of GRB980425
  29. GRB980329 R,I flux calibration and R,I,K upper limits
  30. GRB980425 Optical Follow-up
  31. GRB 980923 BATSE Observations
  32. GRB980703 Very Long Baseline Interferometry
  33. GRB970508 optical observations
  34. GRB971214, association with a Galactic star?
  35. GRB980519, Optical Observations
  36. GRB980703, Host galaxy multicolor photometry
  37. GRB980703 - BeppoSAX/GRBM detection
  38. GRB 980703 (NFI observations)
  39. GRB980703 optical photometry
  40. GRB980703 optical observations
  41. GRB980703 Transient Optical Follow-Up
  42. GRB980703: LOTIS observation at early times
  43. GRB980613 Optical Observations
  44. GRB980703 (optical R observations)
  45. BeppoSAX NFI observations of GRB 980703
  46. GRB 980703: ASM Position & Intensity
  47. GRB980703 optical followup
  48. Radio observations of SGRs
  49. SGR1900+14 field optical observations
  50. GRB 980613: Optical transient and its host galaxy
  51. SGR1627-41, RXTE/ASM observations
  52. GRB 980613: Detection of the probable host galaxy
  53. GRB 980613 Optical Observations
  54. GRB 980613 optical observations
  55. Discovery of a new SGR source, SGR1627-41
  56. GRB980613 Optical Observations
  57. GRB980613 observations from Palomar
  58. GRB 980613 optical/IR obs.
  59. GRB980613 Near Infra-Red Observations
  60. GRB980613, BeppoSAX WFC positions
  61. GRB971214 Secondary Standards
  62. GRB980519 Secondary Standards
  63. SGR1900+14
  64. SGR1900+14
  65. BATSE on-board GRB trigger change
  66. GRB 980519 Optical Observations
  67. GRB 980519
  68. GRB980519 optical observations
  69. GRB 980519 Optical Observations
  70. GRB970519, optical follow-up at Schmidt Calern
  71. GRB980519 Optical Observations
  72. GRB 980519 Optical Observations
  73. GRB980519 optical observations
  74. GRB980515, BeppoSAX IAUC to be submitted
  75. BATSE on-board GRB trigger change
  76. GRB980515: SAX-WFC updated position
  77. BSAX Observations of GRB980425 field
  78. IPN web site of GRBs
  79. SAX J0840.7+2248 Optical Observations
  80. GRB980425: optical obs.
  81. GRB980425: Radio Observations
  82. report on BSAX observations of GRB980425
  83. GRB980326 X-ray Observations
  84. GRB980326, optical observations
  85. GRB980326, optical observations
  86. GRB980329 Keck K-band observations
  87. GRB980329 sub-millimeter observations
  88. GRB980326 optical observations
  89. GRB980329 optical observations
  90. GRB980329 VLA observations
  91. GRB980329 optical observations
  92. GRB980326 optical observations
  93. GRB970508 SAO RAS optical observations
  94. Untitled
  95. Untitled
  96. Untitled
  97. Untitled
  98. Untitled
  99. Untitled
  100. Untitled

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