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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"

28054 results found.

  1. GRB990316 - Optical null results
  2. GRB990308 not a new SGR
  3. GRB 990308a and GRB 990308b
  4. GRB990308, Possible new SGR~0209+70
  5. GRB 990123, Field Photometry
  6. GRB 990217 Optical Observations
  7. BATSE Flight Anomaly
  8. GRB990217: BeppoSAX/GRBM data
  9. GRB990123 observations
  10. GRB990217 Optical observation
  11. GRB990123, Optical Observation
  12. GRB 990123: Discovery of the Probable Host Galaxy
  13. GRB 990123: Reduced HST Images
  14. GRB19990123 observations
  15. GRB 990123: BVRI standards in the field
  16. GRB981220, field photometry
  17. GRB990123, Optical observation
  18. GRB990123, 15-GHz limits
  19. GRB 990123: New Constraints on Possible Foreground Galaxies
  20. GRB990123 Optical Observations
  21. GRB990123, Probability of gravitational lensing
  22. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  23. GRB990123, Preliminary Lens Search Results
  24. On the Lensing Interpretation of GRB 990123
  25. Search for Potential Images of GRB 990123
  26. Search for Potential Images of GRB 990123
  27. GRB990123, Optical BVRI Observations
  28. GRB 990123: near-infrared observations.
  29. GRB990123, OSSE observations
  30. GRB990123: NIR Observation
  31. GRB990123, ASCA X-ray observation of afterglow
  32. "GRB 990123: New BV Observations"
  33. GRB 990123 Optical Follow-Up
  34. GRB 990123: BATSE Observations
  35. GRB990123 Optical Observations
  36. GRB 990123: New Optical Observations, Decay Measure
  37. GRB 990123 Optical Follow-Up
  38. GRB 990123: Possible Gravitationally Lensed Burst?
  39. GRB990123, optical observation
  40. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  41. GRB990123, Optical observation
  42. GRB 990123: Optical Decay Slope
  43. GRB 990123 r-band photometry
  44. GRB 990123 Optical Follow-up
  45. GRB990123, early optical counterpart detection
  46. GRB990123 Optical Observation
  47. Possible identification of SN1999E with GRB980910
  48. Optical Observations of GRB 981220
  49. GRB 981226: radio variable
  50. GRB981220
  51. GRB981220, Correction to GCN 179
  52. GRB 981220 Optical observations
  53. GRB 981226 Optical Observations
  54. GRB 981220 and GRB 981226, optical observations
  55. GRB981226 Optical Observations
  56. GRB981226 BeppoSAX follow up
  57. GRB 981226
  58. GRB 981226 optical observations
  59. GRB981220 B, R and I band observations
  60. Optical Observations of GRB981226
  61. GRB 981220:Optical Observations
  62. GRB 981226 optical observations
  63. GRB 981220
  64. GRB 981220, radio observations
  65. GRB981220 I-band Observations
  66. GRB 981220
  67. GRB 980326/Host Galaxy
  68. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  69. BeppoSAX NFI Observation of GRB980425
  70. GRB980329 R,I flux calibration and R,I,K upper limits
  71. GRB980425 Optical Follow-up
  72. GRB 980923 BATSE Observations
  73. SGR1900+14, BeppoSAX-GRBM observations
  74. GRB970508 optical observations
  75. GRB971214, association with a Galactic star?
  76. GRB980519, Optical Observations
  77. GRB980703 - BeppoSAX/GRBM detection
  78. GRB980703 optical photometry
  79. GRB 980703: BATSE Observations
  80. GRB980703 optical observations
  81. GRB980703: Radio transient
  82. GRB 980703: Spectrum of the proposed optical counterpart
  83. GRB980703 Transient Optical Follow-Up
  84. GRB980703: LOTIS observation at early times
  85. GRB980613 Optical Observations
  86. GRB980703 (I band observations)
  87. BeppoSAX NFI observations of GRB 980703
  88. GRB980519 observation report
  89. GRB980703 optical followup
  90. Radio observations of SGRs
  91. SGR1900+14 field optical observations
  92. GRB980613, optical observations
  93. GRB 980613: Optical transient and its host galaxy
  94. SGR1627-41, RXTE/ASM observations
  95. GRB 980613: Detection of the probable host galaxy
  96. Reduced error box of SGR 1627-41
  97. GRB 980613: BATSE Observations
  98. GRB 980613 Optical Observations
  99. GRB 980613 optical observations
  100. Discovery of a new SGR source, SGR1627-41

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