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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"

24753 results found.

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

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