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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"

24873 results found.

  1. GRB 990510: BeppoSAX/GRBM observations
  2. GRB990510 optical observations
  3. GRB 990510 optical observations
  4. GRB 990506 Radio Observations
  5. GRB 990123, optical monitoring
  6. GRB 990506: BATSE Observations
  7. GRB 990506, optical observations
  8. GRB 990506, Optical Observations
  9. GRB 990506 optical observations
  10. GRB 990506, optical observations
  11. GRB 990506, armchair astronomy
  12. GRB 990506, optical observations from +1 to +3 hours
  13. GRB 990506, optical observations
  14. GRB990506 observation plan
  15. IPN localization for GRB990506
  16. GRB990323 PRECISE IPN POSITION
  17. GRB 990316 Optical Observations
  18. GRB 990316 optical observations
  19. GRB990316: simultaneous optical observation
  20. GRB990316 - Optical null results
  21. GRB990308 not a new SGR
  22. GRB 990308a and GRB 990308b
  23. GRB990308, Possible new SGR~0209+70
  24. GRB 990123, Field Photometry
  25. GRB 990217 Optical Observations
  26. BATSE Flight Anomaly
  27. GRB990217: BeppoSAX/GRBM data
  28. GRB990123 observations
  29. GRB990217 Optical observation
  30. GRB990123, Optical Observation
  31. GRB 990123: Discovery of the Probable Host Galaxy
  32. GRB 990123: Reduced HST Images
  33. GRB19990123 observations
  34. GRB 990123: BVRI standards in the field
  35. GRB981220, field photometry
  36. GRB990123, Optical observation
  37. GRB990123, 15-GHz limits
  38. GRB 990123: New Constraints on Possible Foreground Galaxies
  39. GRB990123 Optical Observations
  40. GRB990123, Probability of gravitational lensing
  41. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  42. GRB990123, Preliminary Lens Search Results
  43. On the Lensing Interpretation of GRB 990123
  44. Search for Potential Images of GRB 990123
  45. Search for Potential Images of GRB 990123
  46. GRB990123, Optical BVRI Observations
  47. GRB 990123: near-infrared observations.
  48. GRB990123, OSSE observations
  49. GRB990123: NIR Observation
  50. GRB990123, ASCA X-ray observation of afterglow
  51. "GRB 990123: New BV Observations"
  52. GRB 990123 Optical Follow-Up
  53. GRB 990123: BATSE Observations
  54. GRB990123 Optical Observations
  55. GRB 990123: New Optical Observations, Decay Measure
  56. GRB 990123 Optical Follow-Up
  57. GRB 990123: Possible Gravitationally Lensed Burst?
  58. GRB990123, optical observation
  59. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  60. GRB990123, Optical observation
  61. GRB 990123: Optical Decay Slope
  62. GRB 990123 r-band photometry
  63. GRB 990123 Optical Follow-up
  64. GRB990123, early optical counterpart detection
  65. GRB990123 Optical Observation
  66. Possible identification of SN1999E with GRB980910
  67. Optical Observations of GRB 981220
  68. GRB 981226: radio variable
  69. GRB981220
  70. GRB981220, Correction to GCN 179
  71. GRB 981220 Optical observations
  72. GRB 981226 Optical Observations
  73. GRB 981220 and GRB 981226, optical observations
  74. GRB981226 Optical Observations
  75. GRB981226 BeppoSAX follow up
  76. GRB 981226
  77. GRB 981226 optical observations
  78. GRB981220 B, R and I band observations
  79. Optical Observations of GRB981226
  80. GRB 981220:Optical Observations
  81. GRB 981226 optical observations
  82. GRB 981220
  83. GRB 981220, radio observations
  84. GRB981220 I-band Observations
  85. GRB 981220
  86. GRB 980326/Host Galaxy
  87. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  88. BeppoSAX NFI Observation of GRB980425
  89. GRB980329 R,I flux calibration and R,I,K upper limits
  90. GRB980425 Optical Follow-up
  91. GRB 980923 BATSE Observations
  92. SGR1900+14, BeppoSAX-GRBM observations
  93. GRB970508 optical observations
  94. GRB971214, association with a Galactic star?
  95. GRB980519, Optical Observations
  96. GRB980703 - BeppoSAX/GRBM detection
  97. GRB980703 optical photometry
  98. GRB 980703: BATSE Observations
  99. GRB980703 optical observations
  100. GRB980703: Radio transient

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