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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"
  1. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  2. GRB 990123: Continued Radio Observations
  3. GRB990123, Preliminary Lens Search Results
  4. GRB 990123: Correction to GCN 230 - C.A. Young added to author list
  5. On the Lensing Interpretation of GRB 990123
  6. Search for Potential Images of GRB 990123
  7. Search for Potential Images of GRB 990123
  8. GRB990123, Optical BVRI Observations
  9. GRB 990123: near-infrared observations.
  10. GRB990123, OSSE observations
  11. GRB 990123: Strong MeV CGRO-COMPTEL detection now posted on WWW
  12. GRB990123: NIR Observation
  13. GRB990123, ASCA X-ray observation of afterglow
  14. "GRB 990123: New BV Observations"
  15. GRB 990123 Optical Follow-Up
  16. GRB 990123; Addendum to GCN 223
  17. GRB 990123: BATSE Observations
  18. GRB 990123 Keck Spectrum update
  19. GRB990123 IPN annulus
  20. GRB 990123 : Multiple and Distorted Images of the Host Galaxy?
  21. GRB990123 Optical Observations
  22. GRB 990123 Spectroscopic Redshifts
  23. GRB 990123: New Optical Observations, Decay Measure
  24. GRB 990123 Optical Follow-Up
  25. GRB 990123: Possible Gravitationally Lensed Burst?
  26. GRB990123, optical observation
  27. GRB 990123 optical observations
  28. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  29. GRB 990123 radio observations
  30. GRB 990123, new radio source
  31. GRB990123 optical observations
  32. GRB990123, Optical observation
  33. GRB 990123: Optical Decay Slope
  34. GRB 990123 r-band photometry
  35. GRB 990123 Optical Follow-up
  36. GRB990123, early optical counterpart detection
  37. GRB990123 Optical Observation
  38. GRB990123, BeppoSAX-NFI X-ray afterglow detection
  39. GRB990123, refined SAX-WFC position
  40. GRB 990123: Bright New Source, Possible Optical Transient
  41. GRB 990123, Radio observations
  42. GRB990123, BeppoSAX WFC detection and NFI planned follow-up
  43. SN 1999E & GRB 980919
  44. Possible identification of SN1999E with GRB980910
  45. Optical Observations of GRB 981220
  46. GRB 981226: radio variable
  47. GRB981220
  48. GRB981220, Correction to GCN 179
  49. GRB981220, Optical Observations
  50. GRB 981220 Optical observations
  51. GRB 981226 Optical Observations
  52. GRB 980613: Spectroscopy of the host galaxy
  53. GRB981226, sub-millimeter observations
  54. GRB981220, sub-millimeter observations
  55. GRB 981220 and GRB 981226, optical observations
  56. GRB981226 Optical Observations
  57. GRB981226 BeppoSAX follow up
  58. GRB 981226 radio observations
  59. GRB 981226
  60. GRB 981226 optical observations
  61. radio observations of GRB 981226
  62. GRB981220 B, R and I band observations
  63. GRB981226, BeppoSAX-NFI follow-up
  64. Optical Observations of GRB981226
  65. GRB 981220:Optical Observations
  66. GRB 981220 optical R and I observations
  67. GRB981226, BeppoSAX Christmas GRB
  68. GRB 981226 - Infrared Observations
  69. GRB 981226 optical observations
  70. GRB 981220
  71. GRB 981220, radio observations
  72. GRB981226 Optical Observation
  73. GRB 981220, radio observations
  74. GRB 981220: BeppoSAX/GRBM results
  75. GRB981220 I-band Observations
  76. GRB981220 Optical Observations
  77. GRB 981220
  78. GRB 981220 Optical Observations
  79. GRB 981220, optical observations
  80. GRB 980326/Host Galaxy
  81. GRB981220 IPN error box
  82. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  83. BeppoSAX NFI Observation of GRB980425
  84. GRB980329 R,I flux calibration and R,I,K upper limits
  85. GRB980425 Optical Follow-up
  86. GRB980425: X-ray revised positions
  87. GRB 980923 BATSE Observations
  88. SGR1900+14, BeppoSAX-GRBM observations
  89. GRB980703 Very Long Baseline Interferometry
  90. GRB970508 optical observations
  91. GRB971214, association with a Galactic star?
  92. Optical Observations of the Host Galaxy of GRB 980519
  93. GRB980519, Optical Observations
  94. GRB980703, Host galaxy multicolor photometry
  95. GRB980703 - BeppoSAX/GRBM detection
  96. GRB 980703 (NFI observations)
  97. GRB980703 optical photometry
  98. GRB 980703: BATSE Observations
  99. GRB980703 optical observations
  100. GRB980703: Radio transient

Advanced

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