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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"

42623 results found.

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

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