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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"

24659 results found.

  1. IPN localization for GRB990506
  2. GRB990323 PRECISE IPN POSITION
  3. GRB 990316 Optical Observations
  4. GRB 990316 optical observations
  5. GRB990316: simultaneous optical observation
  6. GRB990316 - Optical null results
  7. GRB990308 not a new SGR
  8. GRB 990308a and GRB 990308b
  9. GRB990308, Possible new SGR~0209+70
  10. GRB 990123, Field Photometry
  11. GRB 990217 Optical Observations
  12. BATSE Flight Anomaly
  13. GRB990217: BeppoSAX/GRBM data
  14. GRB990123 observations
  15. GRB990217 Optical observation
  16. GRB990123, Optical Observation
  17. GRB 990123: Discovery of the Probable Host Galaxy
  18. GRB 990123: Reduced HST Images
  19. GRB19990123 observations
  20. GRB 990123: BVRI standards in the field
  21. GRB981220, field photometry
  22. GRB990123, Optical observation
  23. GRB990123, 15-GHz limits
  24. GRB 990123: New Constraints on Possible Foreground Galaxies
  25. GRB990123 Optical Observations
  26. GRB990123, Probability of gravitational lensing
  27. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  28. GRB990123, Preliminary Lens Search Results
  29. On the Lensing Interpretation of GRB 990123
  30. Search for Potential Images of GRB 990123
  31. Search for Potential Images of GRB 990123
  32. GRB990123, Optical BVRI Observations
  33. GRB 990123: near-infrared observations.
  34. GRB990123, OSSE observations
  35. GRB990123: NIR Observation
  36. GRB990123, ASCA X-ray observation of afterglow
  37. "GRB 990123: New BV Observations"
  38. GRB 990123 Optical Follow-Up
  39. GRB 990123: BATSE Observations
  40. GRB990123 Optical Observations
  41. GRB 990123: New Optical Observations, Decay Measure
  42. GRB 990123 Optical Follow-Up
  43. GRB 990123: Possible Gravitationally Lensed Burst?
  44. GRB990123, optical observation
  45. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  46. GRB990123, Optical observation
  47. GRB 990123: Optical Decay Slope
  48. GRB 990123 r-band photometry
  49. GRB 990123 Optical Follow-up
  50. GRB990123, early optical counterpart detection
  51. GRB990123 Optical Observation
  52. Possible identification of SN1999E with GRB980910
  53. Optical Observations of GRB 981220
  54. GRB 981226: radio variable
  55. GRB981220
  56. GRB981220, Correction to GCN 179
  57. GRB 981220 Optical observations
  58. GRB 981226 Optical Observations
  59. GRB 981220 and GRB 981226, optical observations
  60. GRB981226 Optical Observations
  61. GRB981226 BeppoSAX follow up
  62. GRB 981226
  63. GRB 981226 optical observations
  64. GRB981220 B, R and I band observations
  65. Optical Observations of GRB981226
  66. GRB 981220:Optical Observations
  67. GRB 981226 optical observations
  68. GRB 981220
  69. GRB 981220, radio observations
  70. GRB981220 I-band Observations
  71. GRB 981220
  72. GRB 980326/Host Galaxy
  73. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  74. BeppoSAX NFI Observation of GRB980425
  75. GRB980329 R,I flux calibration and R,I,K upper limits
  76. GRB980425 Optical Follow-up
  77. GRB 980923 BATSE Observations
  78. SGR1900+14, BeppoSAX-GRBM observations
  79. GRB970508 optical observations
  80. GRB971214, association with a Galactic star?
  81. GRB980519, Optical Observations
  82. GRB980703 - BeppoSAX/GRBM detection
  83. GRB980703 optical photometry
  84. GRB 980703: BATSE Observations
  85. GRB980703 optical observations
  86. GRB980703: Radio transient
  87. GRB 980703: Spectrum of the proposed optical counterpart
  88. GRB980703 Transient Optical Follow-Up
  89. GRB980703: LOTIS observation at early times
  90. GRB980613 Optical Observations
  91. GRB980703 (I band observations)
  92. BeppoSAX NFI observations of GRB 980703
  93. GRB980519 observation report
  94. GRB980703 optical followup
  95. Radio observations of SGRs
  96. SGR1900+14 field optical observations
  97. GRB980613, optical observations
  98. GRB 980613: Optical transient and its host galaxy
  99. SGR1627-41, RXTE/ASM observations
  100. GRB 980613: Detection of the probable host galaxy

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