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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"

43604 results found.

  1. GRB 990123 Optical Follow-up
  2. GRB990123, early optical counterpart detection
  3. GRB990123 Optical Observation
  4. GRB990123, BeppoSAX-NFI X-ray afterglow detection
  5. GRB990123, refined SAX-WFC position
  6. GRB 990123: Bright New Source, Possible Optical Transient
  7. GRB 990123, Radio observations
  8. GRB990123, BeppoSAX WFC detection and NFI planned follow-up
  9. SN 1999E & GRB 980919
  10. Possible identification of SN1999E with GRB980910
  11. Optical Observations of GRB 981220
  12. GRB 981226: radio variable
  13. GRB981220
  14. GRB981220, Correction to GCN 179
  15. GRB981220, Optical Observations
  16. GRB 981220 Optical observations
  17. GRB 981226 Optical Observations
  18. GRB 980613: Spectroscopy of the host galaxy
  19. GRB981226, sub-millimeter observations
  20. GRB981220, sub-millimeter observations
  21. GRB 981220 and GRB 981226, optical observations
  22. GRB981226 Optical Observations
  23. GRB981226 BeppoSAX follow up
  24. GRB 981226
  25. GRB 981226 optical observations
  26. radio observations of GRB 981226
  27. GRB981220 B, R and I band observations
  28. GRB981226, BeppoSAX-NFI follow-up
  29. Optical Observations of GRB981226
  30. GRB 981220:Optical Observations
  31. GRB 981220 optical R and I observations
  32. GRB981226, BeppoSAX Christmas GRB
  33. GRB 981226 - Infrared Observations
  34. GRB 981226 optical observations
  35. GRB 981220
  36. GRB 981220, radio observations
  37. GRB981226 Optical Observation
  38. GRB 981220, radio observations
  39. GRB 981220: BeppoSAX/GRBM results
  40. GRB981220 I-band Observations
  41. GRB981220 Optical Observations
  42. GRB 981220
  43. GRB 981220 Optical Observations
  44. GRB 980326/Host Galaxy
  45. GRB981220 IPN error box
  46. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  47. BeppoSAX NFI Observation of GRB980425
  48. GRB980329 R,I flux calibration and R,I,K upper limits
  49. GRB980425 Optical Follow-up
  50. GRB980425: X-ray revised positions
  51. GRB 980923 BATSE Observations
  52. SGR1900+14, BeppoSAX-GRBM observations
  53. GRB980703 Very Long Baseline Interferometry
  54. GRB970508 optical observations
  55. GRB971214, association with a Galactic star?
  56. Optical Observations of the Host Galaxy of GRB 980519
  57. GRB980519, Optical Observations
  58. GRB980703 - BeppoSAX/GRBM detection
  59. GRB 980703 (NFI observations)
  60. GRB980703 optical photometry
  61. GRB 980703: BATSE Observations
  62. GRB980703 optical observations
  63. GRB980703: Radio transient
  64. GRB980703 H-band Observations
  65. GRB 980703: Spectrum of the proposed optical counterpart
  66. RXTE Observation of GRB 980706
  67. GRB980703: Spectrum of the proposed optical counterpart
  68. GRB980703 Transient Optical Follow-Up
  69. GRB980703: LOTIS observation at early times
  70. GRB980613 Optical Observations
  71. GRB 980703
  72. GRB980703 (I band observations)
  73. GRB 980703 H-band Observations
  74. GRB980703 (optical R observations)
  75. GRB980706
  76. GRB980703: radio source/optical transient
  77. BeppoSAX NFI observations of GRB 980703
  78. GRB 980703: ASM Position & Intensity
  79. GRB980703
  80. GRB980519 observation report
  81. GRB980703 optical followup
  82. SGR1627-41
  83. Radio observations of SGRs
  84. SGR1900+14 field optical observations
  85. GRB 980613 Near-IR observations
  86. GRB980613, optical observations
  87. GRB 980613: Optical transient and its host galaxy
  88. SGR1627-41, RXTE/ASM observations
  89. SGR1627-41, Refined IPN annulus location
  90. GRB 980613: Detection of the probable host galaxy
  91. Reduced error box of SGR 1627-41
  92. GRB 980613: BATSE Observations
  93. SGR1627-41, BeppoSAX-GRBM detections
  94. SGR 1627-41
  95. GRB 980613 Optical Observations
  96. GRB 980613 optical observations
  97. Discovery of a new SGR source, SGR1627-41
  98. GRB980613 Optical Observations
  99. GRB980613 observations from Palomar
  100. GRB980613 BeppoSAX-NFI follow up

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