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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"

45423 results found.

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

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