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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').

17298 results found.

  1. GRB 990123 r-band photometry
  2. GRB 990123 Optical Follow-up
  3. GRB990123, early optical counterpart detection
  4. GRB 990123, Radio observations
  5. GRB990123, BeppoSAX WFC detection and NFI planned follow-up
  6. Possible identification of SN1999E with GRB980910
  7. Optical Observations of GRB 981220
  8. GRB 981226: radio variable
  9. GRB 981226 Optical Observations
  10. GRB981226 BeppoSAX follow up
  11. GRB 981226
  12. GRB 981226 optical observations
  13. GRB981220 B, R and I band observations
  14. GRB 981220:Optical Observations
  15. GRB 981226 optical observations
  16. GRB 981220, radio observations
  17. GRB 981220: BeppoSAX/GRBM results
  18. GRB981220 Optical Observations
  19. GRB 981220
  20. GRB 980326/Host Galaxy
  21. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  22. BeppoSAX NFI Observation of GRB980425
  23. GRB980329 R,I flux calibration and R,I,K upper limits
  24. GRB980425 Optical Follow-up
  25. GRB980425: X-ray revised positions
  26. GRB980703 Very Long Baseline Interferometry
  27. GRB970508 optical observations
  28. GRB980519, Optical Observations
  29. GRB980703 - BeppoSAX/GRBM detection
  30. GRB980703 optical photometry
  31. GRB 980703: BATSE Observations
  32. GRB980703 optical observations
  33. GRB980703: Radio transient
  34. GRB980703 Transient Optical Follow-Up
  35. GRB980703: LOTIS observation at early times
  36. GRB980613 Optical Observations
  37. GRB 980703
  38. BeppoSAX NFI observations of GRB 980703
  39. GRB980703 optical followup
  40. Radio observations of SGRs
  41. SGR1900+14 field optical observations
  42. GRB 980613: Optical transient and its host galaxy
  43. SGR1627-41, RXTE/ASM observations
  44. GRB 980613: Detection of the probable host galaxy
  45. GRB 980613 Optical Observations
  46. GRB 980613 optical observations
  47. Discovery of a new SGR source, SGR1627-41
  48. GRB980613 Optical Observations
  49. GRB980613 observations from Palomar
  50. GRB980613 Near Infra-Red Observations
  51. GRB980613, BeppoSAX WFC positions
  52. GRB971214 Secondary Standards
  53. GRB980519 Secondary Standards
  54. GRB 980519 Optical Observations
  55. GRB 980519
  56. GRB980519 optical observations
  57. GRB 980519 Optical Observations
  58. GRB980519 BATSE Observations
  59. GRB970519, optical follow-up at Schmidt Calern
  60. GRB980519 Optical Observations
  61. GRB 980519 Optical Observations
  62. GRB980515, BeppoSAX IAUC to be submitted
  63. GRB980519, BeppoSAX-WFC position
  64. BeppoSAX GRB ALERT: updated position of grb980515
  65. GRB 980425 Brightness Temperature
  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. GRB980329 Keck K-band observations
  75. GRB980329 sub-millimeter observations
  76. GRB980326 optical observations
  77. GRB980329 optical observations
  78. GRB980329 VLA observations
  79. GRB980329 optical observations
  80. GRB980326 optical observations
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  87. Untitled
  88. Untitled
  89. Untitled
  90. Untitled
  91. Untitled
  92. GRB 971214: KPNO Optical Observations
  93. Untitled
  94. GRB 971214: Optical Observations
  95. Radio Observations of GRB 971214 at the VLA
  96. GRB 971024: KPNO Optical Observations
  97. RXTE Observations of SGR 1814-13
  98. GRB 970828: Palomar Observations

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