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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"

36789 results found.

  1. Search for Potential Images of GRB 990123
  2. Search for Potential Images of GRB 990123
  3. GRB990123, Optical BVRI Observations
  4. GRB 990123: near-infrared observations.
  5. GRB990123, OSSE observations
  6. GRB 990123: Strong MeV CGRO-COMPTEL detection now posted on WWW
  7. "GRB 990123: New BV Observations"
  8. GRB 990123 Optical Follow-Up
  9. GRB 990123; Addendum to GCN 223
  10. GRB 990123: BATSE Observations
  11. GRB 990123 Keck Spectrum update
  12. GRB 990123 : Multiple and Distorted Images of the Host Galaxy?
  13. GRB990123 Optical Observations
  14. GRB 990123 Spectroscopic Redshifts
  15. GRB 990123: New Optical Observations, Decay Measure
  16. GRB 990123 Optical Follow-Up
  17. GRB 990123: Possible Gravitationally Lensed Burst?
  18. GRB 990123 optical observations
  19. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  20. GRB 990123 radio observations
  21. GRB 990123, new radio source
  22. GRB990123, Optical observation
  23. GRB 990123: Optical Decay Slope
  24. GRB 990123 r-band photometry
  25. GRB 990123 Optical Follow-up
  26. GRB990123, early optical counterpart detection
  27. GRB990123 Optical Observation
  28. GRB 990123: Bright New Source, Possible Optical Transient
  29. GRB 990123, Radio observations
  30. SN 1999E & GRB 980919
  31. Possible identification of SN1999E with GRB980910
  32. Optical Observations of GRB 981220
  33. GRB 981226: radio variable
  34. GRB981220
  35. GRB981220, Optical Observations
  36. GRB 981220 Optical observations
  37. GRB 981226 Optical Observations
  38. GRB 980613: Spectroscopy of the host galaxy
  39. GRB981226, sub-millimeter observations
  40. GRB981220, sub-millimeter observations
  41. GRB 981220 and GRB 981226, optical observations
  42. GRB 981226 radio observations
  43. GRB 981226
  44. GRB 981226 optical observations
  45. radio observations of GRB 981226
  46. GRB981220 B, R and I band observations
  47. GRB 981220:Optical Observations
  48. GRB 981220 optical R and I observations
  49. GRB981226, BeppoSAX Christmas GRB
  50. GRB 981226 - Infrared Observations
  51. GRB 981226 optical observations
  52. GRB 981220
  53. GRB 981220, radio observations
  54. GRB981226 Optical Observation
  55. GRB 981220, radio observations
  56. GRB 981220: BeppoSAX/GRBM results
  57. GRB981220 I-band Observations
  58. GRB 981220
  59. GRB 981220 Optical Observations
  60. GRB 981220, optical observations
  61. GRB 980326/Host Galaxy
  62. GRB981220 IPN error box
  63. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  64. GRB980329 R,I flux calibration and R,I,K upper limits
  65. GRB980425: X-ray revised positions
  66. GRB 980923 BATSE 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: Radio transient
  78. GRB980703 H-band Observations
  79. GRB 980703: Spectrum of the proposed optical counterpart
  80. RXTE Observation of GRB 980706
  81. GRB980703: Spectrum of the proposed optical counterpart
  82. GRB980703 Transient Optical Follow-Up
  83. GRB980703: LOTIS observation at early times
  84. GRB980613 Optical Observations
  85. GRB 980703
  86. GRB 980703 H-band Observations
  87. GRB980703 (optical R observations)
  88. GRB980706
  89. GRB980703: radio source/optical transient
  90. BeppoSAX NFI observations of GRB 980703
  91. GRB 980703: ASM Position & Intensity
  92. GRB980703
  93. GRB980703 optical followup
  94. GRB 980613 Near-IR observations
  95. GRB980613, optical observations
  96. GRB 980613: Optical transient and its host galaxy
  97. GRB 980613: Detection of the probable host galaxy
  98. GRB 980613: BATSE Observations
  99. GRB 980613 Optical Observations
  100. GRB 980613 optical observations

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