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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"

37070 results found.

  1. GRB 990123, Radio observations
  2. SN 1999E & GRB 980919
  3. Possible identification of SN1999E with GRB980910
  4. Optical Observations of GRB 981220
  5. GRB 981226: radio variable
  6. GRB981220
  7. GRB981220, Optical Observations
  8. GRB 981220 Optical observations
  9. GRB 981226 Optical Observations
  10. GRB 980613: Spectroscopy of the host galaxy
  11. GRB981226, sub-millimeter observations
  12. GRB981220, sub-millimeter observations
  13. GRB 981220 and GRB 981226, optical observations
  14. GRB981226 BeppoSAX follow up
  15. GRB 981226 radio observations
  16. GRB 981226
  17. GRB 981226 optical observations
  18. radio observations of GRB 981226
  19. GRB981220 B, R and I band observations
  20. GRB981226, BeppoSAX-NFI follow-up
  21. Optical Observations of GRB981226
  22. GRB 981220:Optical Observations
  23. GRB 981220 optical R and I observations
  24. GRB981226, BeppoSAX Christmas GRB
  25. GRB 981226 - Infrared Observations
  26. GRB 981226 optical observations
  27. GRB 981220
  28. GRB 981220, radio observations
  29. GRB981226 Optical Observation
  30. GRB 981220, radio observations
  31. GRB 981220: BeppoSAX/GRBM results
  32. GRB981220 I-band Observations
  33. GRB981220 Optical Observations
  34. GRB 981220
  35. GRB 981220 Optical Observations
  36. GRB 981220, optical observations
  37. GRB 980326/Host Galaxy
  38. GRB981220 IPN error box
  39. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  40. GRB980329 R,I flux calibration and R,I,K upper limits
  41. GRB980425: X-ray revised positions
  42. GRB 980923 BATSE Observations
  43. GRB980703 Very Long Baseline Interferometry
  44. GRB970508 optical observations
  45. GRB971214, association with a Galactic star?
  46. Optical Observations of the Host Galaxy of GRB 980519
  47. GRB980519, Optical Observations
  48. GRB980703, Host galaxy multicolor photometry
  49. GRB980703 - BeppoSAX/GRBM detection
  50. GRB 980703 (NFI observations)
  51. GRB980703 optical photometry
  52. GRB 980703: BATSE Observations
  53. GRB980703 optical observations
  54. GRB980703: Radio transient
  55. GRB980703 H-band Observations
  56. GRB 980703: Spectrum of the proposed optical counterpart
  57. RXTE Observation of GRB 980706
  58. GRB980703: Spectrum of the proposed optical counterpart
  59. GRB980703 Transient Optical Follow-Up
  60. GRB980703: LOTIS observation at early times
  61. GRB980613 Optical Observations
  62. GRB 980703
  63. GRB 980703 H-band Observations
  64. GRB980703 (optical R observations)
  65. GRB980706
  66. GRB980703: radio source/optical transient
  67. BeppoSAX NFI observations of GRB 980703
  68. GRB 980703: ASM Position & Intensity
  69. GRB980703
  70. GRB980703 optical followup
  71. GRB 980613 Near-IR observations
  72. GRB980613, optical observations
  73. GRB 980613: Optical transient and its host galaxy
  74. SGR1627-41, RXTE/ASM observations
  75. GRB 980613: Detection of the probable host galaxy
  76. GRB 980613: BATSE Observations
  77. GRB 980613 Optical Observations
  78. GRB 980613 optical observations
  79. GRB980613 Optical Observations
  80. GRB980613 observations from Palomar
  81. GRB980613 BeppoSAX-NFI follow up
  82. GRB 980613 new optical/IR observations
  83. GRB 980613 optical/IR obs.
  84. GRB980613 Near Infra-Red Observations
  85. GRB980611
  86. GRB980613, BeppoSAX WFC positions
  87. GRB971214 Secondary Standards
  88. GRB980519 Secondary Standards
  89. BATSE on-board GRB trigger change
  90. GRB 980519 Optical Observations
  91. GRB980519 optical observations
  92. GRB 980519
  93. GRB980519 optical observations
  94. GRB 980519 Optical Observations
  95. GRB980519 BATSE Observations
  96. GRB970519, optical follow-up at Schmidt Calern
  97. GRB980519 optical observations
  98. GRB980519 Optical Observations
  99. GRB980519 Optical Observations
  100. GRB980519 IPN POSITION

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