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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"

35958 results found.

  1. Optical Observations of GRB 981220
  2. GRB 981226: radio variable
  3. GRB981220
  4. GRB981220, Optical Observations
  5. GRB 981220 Optical observations
  6. GRB 981226 Optical Observations
  7. GRB 980613: Spectroscopy of the host galaxy
  8. GRB981226, sub-millimeter observations
  9. GRB981220, sub-millimeter observations
  10. GRB 981220 and GRB 981226, optical observations
  11. GRB 981226 radio observations
  12. GRB 981226
  13. GRB 981226 optical observations
  14. radio observations of GRB 981226
  15. GRB981220 B, R and I band observations
  16. GRB 981220:Optical Observations
  17. GRB 981220 optical R and I observations
  18. GRB981226, BeppoSAX Christmas GRB
  19. GRB 981226 - Infrared Observations
  20. GRB 981226 optical observations
  21. GRB 981220
  22. GRB 981220, radio observations
  23. GRB981226 Optical Observation
  24. GRB 981220, radio observations
  25. GRB 981220: BeppoSAX/GRBM results
  26. GRB981220 I-band Observations
  27. GRB 981220
  28. GRB 981220 Optical Observations
  29. GRB 981220, optical observations
  30. GRB 980326/Host Galaxy
  31. GRB981220 IPN error box
  32. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  33. GRB980329 R,I flux calibration and R,I,K upper limits
  34. GRB980425: X-ray revised positions
  35. GRB 980923 BATSE Observations
  36. GRB980703 Very Long Baseline Interferometry
  37. GRB970508 optical observations
  38. GRB971214, association with a Galactic star?
  39. Optical Observations of the Host Galaxy of GRB 980519
  40. GRB980519, Optical Observations
  41. GRB980703, Host galaxy multicolor photometry
  42. GRB980703 - BeppoSAX/GRBM detection
  43. GRB 980703 (NFI observations)
  44. GRB980703 optical photometry
  45. GRB 980703: BATSE Observations
  46. GRB980703: Radio transient
  47. GRB980703 H-band Observations
  48. GRB 980703: Spectrum of the proposed optical counterpart
  49. RXTE Observation of GRB 980706
  50. GRB980703: Spectrum of the proposed optical counterpart
  51. GRB980703 Transient Optical Follow-Up
  52. GRB980703: LOTIS observation at early times
  53. GRB980613 Optical Observations
  54. GRB 980703
  55. GRB 980703 H-band Observations
  56. GRB980703 (optical R observations)
  57. GRB980706
  58. GRB980703: radio source/optical transient
  59. BeppoSAX NFI observations of GRB 980703
  60. GRB 980703: ASM Position & Intensity
  61. GRB980703
  62. GRB980703 optical followup
  63. GRB 980613 Near-IR observations
  64. GRB980613, optical observations
  65. GRB 980613: Optical transient and its host galaxy
  66. GRB 980613: Detection of the probable host galaxy
  67. GRB 980613: BATSE Observations
  68. GRB 980613 Optical Observations
  69. GRB 980613 optical observations
  70. GRB980613 Optical Observations
  71. GRB980613 observations from Palomar
  72. GRB980613 BeppoSAX-NFI follow up
  73. GRB 980613 new optical/IR observations
  74. GRB 980613 optical/IR obs.
  75. GRB980613 Near Infra-Red Observations
  76. GRB980611
  77. GRB980613, BeppoSAX WFC positions
  78. GRB971214 Secondary Standards
  79. GRB980519 Secondary Standards
  80. BATSE on-board GRB trigger change
  81. GRB 980519 Optical Observations
  82. GRB980519 optical observations
  83. GRB 980519
  84. GRB980519 optical observations
  85. GRB 980519 Optical Observations
  86. GRB980519 BATSE Observations
  87. GRB970519, optical follow-up at Schmidt Calern
  88. GRB980519 optical observations
  89. GRB980519 Optical Observations
  90. GRB980519 Optical Observations
  91. GRB980519 IPN POSITION
  92. GRB980519 Optical Observations
  93. GRB 980519 Optical Observations
  94. GRB980519 optical observations
  95. GRB980515, BeppoSAX IAUC to be submitted
  96. BATSE on-board GRB trigger change
  97. BeppoSAX GRB ALERT: updated position of grb980515
  98. GRB 980425 Radio Light Curve
  99. GRB 980425 Brightness Temperature
  100. GRB980425 BATSE observations

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