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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').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

45422 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. GRB 990123 radio observations
  7. GRB 990123, new radio source
  8. GRB990123 optical observations
  9. GRB990123, Optical observation
  10. GRB 990123: Optical Decay Slope
  11. GRB 990123 r-band photometry
  12. GRB 990123 Optical Follow-up
  13. GRB990123, early optical counterpart detection
  14. GRB990123 Optical Observation
  15. GRB990123, BeppoSAX-NFI X-ray afterglow detection
  16. GRB990123, refined SAX-WFC position
  17. GRB 990123: Bright New Source, Possible Optical Transient
  18. GRB 990123, Radio observations
  19. GRB990123, BeppoSAX WFC detection and NFI planned follow-up
  20. SN 1999E & GRB 980919
  21. Possible identification of SN1999E with GRB980910
  22. Optical Observations of GRB 981220
  23. GRB 981226: radio variable
  24. GRB981220
  25. GRB981220, Correction to GCN 179
  26. GRB981220, Optical Observations
  27. GRB 981220 Optical observations
  28. GRB 981226 Optical Observations
  29. GRB 980613: Spectroscopy of the host galaxy
  30. GRB981226, sub-millimeter observations
  31. GRB981220, sub-millimeter observations
  32. GRB 981220 and GRB 981226, optical observations
  33. GRB981226 Optical Observations
  34. GRB981226 BeppoSAX follow up
  35. GRB 981226 radio observations
  36. GRB 981226
  37. GRB 981226 optical observations
  38. radio observations of GRB 981226
  39. GRB981220 B, R and I band observations
  40. GRB981226, BeppoSAX-NFI follow-up
  41. Optical Observations of GRB981226
  42. GRB 981220:Optical Observations
  43. GRB 981220 optical R and I observations
  44. GRB981226, BeppoSAX Christmas GRB
  45. GRB 981226 - Infrared Observations
  46. GRB 981226 optical observations
  47. GRB 981220
  48. GRB 981220, radio observations
  49. GRB981226 Optical Observation
  50. GRB 981220, radio observations
  51. GRB 981220: BeppoSAX/GRBM results
  52. GRB981220 I-band Observations
  53. GRB981220 Optical Observations
  54. GRB 981220
  55. GRB 981220 Optical Observations
  56. GRB 981220, optical observations
  57. GRB 980326/Host Galaxy
  58. GRB981220 IPN error box
  59. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  60. BeppoSAX NFI Observation of GRB980425
  61. GRB980329 R,I flux calibration and R,I,K upper limits
  62. GRB980425 Optical Follow-up
  63. GRB980425: X-ray revised positions
  64. GRB 980923 BATSE Observations
  65. SGR1900+14, BeppoSAX-GRBM observations
  66. GRB980703 Very Long Baseline Interferometry
  67. GRB970508 optical observations
  68. GRB971214, association with a Galactic star?
  69. Optical Observations of the Host Galaxy of GRB 980519
  70. GRB980519, Optical Observations
  71. GRB980703, Host galaxy multicolor photometry
  72. GRB980703 - BeppoSAX/GRBM detection
  73. GRB 980703 (NFI observations)
  74. GRB980703 optical photometry
  75. GRB 980703: BATSE Observations
  76. GRB980703 optical observations
  77. GRB980703: Radio transient
  78. GRB980703 H-band Observations
  79. GRB 980703: Spectrum of the proposed optical counterpart
  80. RXTE Observation of GRB 980706
  81. GRB980703: Spectrum of the proposed optical counterpart
  82. GRB980703 Transient Optical Follow-Up
  83. GRB980703: LOTIS observation at early times
  84. GRB980613 Optical Observations
  85. GRB 980703
  86. GRB980703 (I band observations)
  87. GRB 980703 H-band Observations
  88. GRB980703 (optical R observations)
  89. GRB980706
  90. GRB980703: radio source/optical transient
  91. BeppoSAX NFI observations of GRB 980703
  92. GRB 980703: ASM Position & Intensity
  93. GRB980703
  94. GRB980519 observation report
  95. GRB980703 optical followup
  96. SGR1627-41
  97. Radio observations of SGRs
  98. SGR1900+14 field optical observations
  99. GRB 980613 Near-IR observations
  100. GRB980613, optical observations

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