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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"

36301 results found.

  1. GRB 990123: Correction to GCN 230 - C.A. Young added to author list
  2. On the Lensing Interpretation of GRB 990123
  3. Search for Potential Images of GRB 990123
  4. Search for Potential Images of GRB 990123
  5. GRB990123, Optical BVRI Observations
  6. GRB 990123: near-infrared observations.
  7. GRB990123, OSSE observations
  8. GRB 990123: Strong MeV CGRO-COMPTEL detection now posted on WWW
  9. "GRB 990123: New BV Observations"
  10. GRB 990123 Optical Follow-Up
  11. GRB 990123; Addendum to GCN 223
  12. GRB 990123: BATSE Observations
  13. GRB 990123 Keck Spectrum update
  14. GRB 990123 : Multiple and Distorted Images of the Host Galaxy?
  15. GRB990123 Optical Observations
  16. GRB 990123 Spectroscopic Redshifts
  17. GRB 990123: New Optical Observations, Decay Measure
  18. GRB 990123 Optical Follow-Up
  19. GRB 990123: Possible Gravitationally Lensed Burst?
  20. GRB 990123 optical observations
  21. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  22. GRB 990123 radio observations
  23. GRB 990123, new radio source
  24. GRB990123, Optical observation
  25. GRB 990123: Optical Decay Slope
  26. GRB 990123 r-band photometry
  27. GRB 990123 Optical Follow-up
  28. GRB990123, early optical counterpart detection
  29. GRB990123 Optical Observation
  30. GRB990123, BeppoSAX-NFI X-ray afterglow detection
  31. GRB 990123: Bright New Source, Possible Optical Transient
  32. GRB 990123, Radio observations
  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, Optical Observations
  39. GRB 981220 Optical observations
  40. GRB 981226 Optical Observations
  41. GRB 980613: Spectroscopy of the host galaxy
  42. GRB981226, sub-millimeter observations
  43. GRB981220, sub-millimeter observations
  44. GRB 981220 and GRB 981226, optical observations
  45. GRB981226 BeppoSAX follow up
  46. GRB 981226 radio observations
  47. GRB 981226
  48. GRB 981226 optical observations
  49. radio observations of GRB 981226
  50. GRB981220 B, R and I band observations
  51. GRB981226, BeppoSAX-NFI follow-up
  52. Optical Observations of GRB981226
  53. GRB 981220:Optical Observations
  54. GRB 981220 optical R and I observations
  55. GRB981226, BeppoSAX Christmas GRB
  56. GRB 981226 - Infrared Observations
  57. GRB 981226 optical observations
  58. GRB 981220
  59. GRB 981220, radio observations
  60. GRB981226 Optical Observation
  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 981220, optical observations
  68. GRB 980326/Host Galaxy
  69. GRB981220 IPN error box
  70. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  71. GRB980329 R,I flux calibration and R,I,K upper limits
  72. GRB980425: X-ray revised positions
  73. GRB 980923 BATSE Observations
  74. GRB980703 Very Long Baseline Interferometry
  75. GRB970508 optical observations
  76. GRB971214, association with a Galactic star?
  77. Optical Observations of the Host Galaxy of GRB 980519
  78. GRB980519, Optical Observations
  79. GRB980703, Host galaxy multicolor photometry
  80. GRB980703 - BeppoSAX/GRBM detection
  81. GRB 980703 (NFI observations)
  82. GRB980703 optical photometry
  83. GRB 980703: BATSE Observations
  84. GRB980703 optical observations
  85. GRB980703: Radio transient
  86. GRB980703 H-band Observations
  87. GRB 980703: Spectrum of the proposed optical counterpart
  88. RXTE Observation of GRB 980706
  89. GRB980703: Spectrum of the proposed optical counterpart
  90. GRB980703 Transient Optical Follow-Up
  91. GRB980703: LOTIS observation at early times
  92. GRB980613 Optical Observations
  93. GRB 980703
  94. GRB 980703 H-band Observations
  95. GRB980703 (optical R observations)
  96. GRB980706
  97. GRB980703: radio source/optical transient
  98. BeppoSAX NFI observations of GRB 980703
  99. GRB 980703: ASM Position & Intensity
  100. GRB980703

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