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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"

27650 results found.

  1. GRB 990123, Field Photometry
  2. GRB 990217 Optical Observations
  3. BATSE Flight Anomaly
  4. GRB990217: BeppoSAX/GRBM data
  5. GRB990123 observations
  6. GRB990217 Optical observation
  7. GRB990123, Optical Observation
  8. GRB 990123: Discovery of the Probable Host Galaxy
  9. GRB 990123: Reduced HST Images
  10. GRB19990123 observations
  11. GRB 990123: BVRI standards in the field
  12. GRB981220, field photometry
  13. GRB990123, Optical observation
  14. GRB990123, 15-GHz limits
  15. GRB 990123: New Constraints on Possible Foreground Galaxies
  16. GRB990123 Optical Observations
  17. GRB990123, Probability of gravitational lensing
  18. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  19. GRB990123, Preliminary Lens Search Results
  20. On the Lensing Interpretation of GRB 990123
  21. Search for Potential Images of GRB 990123
  22. Search for Potential Images of GRB 990123
  23. GRB990123, Optical BVRI Observations
  24. GRB 990123: near-infrared observations.
  25. GRB990123, OSSE observations
  26. GRB990123: NIR Observation
  27. GRB990123, ASCA X-ray observation of afterglow
  28. "GRB 990123: New BV Observations"
  29. GRB 990123 Optical Follow-Up
  30. GRB 990123: BATSE Observations
  31. GRB990123 Optical Observations
  32. GRB 990123: New Optical Observations, Decay Measure
  33. GRB 990123 Optical Follow-Up
  34. GRB 990123: Possible Gravitationally Lensed Burst?
  35. GRB990123, optical observation
  36. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  37. GRB990123, Optical observation
  38. GRB 990123: Optical Decay Slope
  39. GRB 990123 r-band photometry
  40. GRB 990123 Optical Follow-up
  41. GRB990123, early optical counterpart detection
  42. GRB990123 Optical Observation
  43. Possible identification of SN1999E with GRB980910
  44. Optical Observations of GRB 981220
  45. GRB 981226: radio variable
  46. GRB981220
  47. GRB981220, Correction to GCN 179
  48. GRB 981220 Optical observations
  49. GRB 981226 Optical Observations
  50. GRB 981220 and GRB 981226, optical observations
  51. GRB981226 Optical Observations
  52. GRB981226 BeppoSAX follow up
  53. GRB 981226
  54. GRB 981226 optical observations
  55. GRB981220 B, R and I band observations
  56. Optical Observations of GRB981226
  57. GRB 981220:Optical Observations
  58. GRB 981226 optical observations
  59. GRB 981220
  60. GRB 981220, radio observations
  61. GRB981220 I-band Observations
  62. GRB 981220
  63. GRB 980326/Host Galaxy
  64. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  65. BeppoSAX NFI Observation of GRB980425
  66. GRB980329 R,I flux calibration and R,I,K upper limits
  67. GRB980425 Optical Follow-up
  68. GRB 980923 BATSE Observations
  69. SGR1900+14, BeppoSAX-GRBM observations
  70. GRB970508 optical observations
  71. GRB971214, association with a Galactic star?
  72. GRB980519, Optical Observations
  73. GRB980703 - BeppoSAX/GRBM detection
  74. GRB980703 optical photometry
  75. GRB 980703: BATSE Observations
  76. GRB980703 optical observations
  77. GRB980703: Radio transient
  78. GRB 980703: Spectrum of the proposed optical counterpart
  79. GRB980703 Transient Optical Follow-Up
  80. GRB980703: LOTIS observation at early times
  81. GRB980613 Optical Observations
  82. GRB980703 (I band observations)
  83. BeppoSAX NFI observations of GRB 980703
  84. GRB980519 observation report
  85. GRB980703 optical followup
  86. Radio observations of SGRs
  87. SGR1900+14 field optical observations
  88. GRB980613, optical observations
  89. GRB 980613: Optical transient and its host galaxy
  90. SGR1627-41, RXTE/ASM observations
  91. GRB 980613: Detection of the probable host galaxy
  92. Reduced error box of SGR 1627-41
  93. GRB 980613: BATSE Observations
  94. GRB 980613 Optical Observations
  95. GRB 980613 optical observations
  96. Discovery of a new SGR source, SGR1627-41
  97. GRB980613 Optical Observations
  98. GRB980613 observations from Palomar
  99. GRB 980613 optical/IR obs.
  100. GRB980613 Near Infra-Red Observations

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