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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"

42627 results found.

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

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