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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"

26494 results found.

  1. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  2. Optical report on X-ray/GRB transient
  3. BeppoSAX: A new fast X-ray transient
  4. GRB990510: photometric and spectroscopic observations with the VLT
  5. GRB 990510: optical linear polarization
  6. GRB 990510: optical observations
  7. GRB990510, VI observations
  8. GRB 990510: Broad Band Break
  9. GRB 990510: BATSE Observations
  10. GRB990510: optical observation
  11. GRB 990510: BeppoSAX/GRBM observations
  12. GRB990510 optical observations
  13. GRB 990510 optical observations
  14. GRB 990510 optical observations
  15. GRB 990506 Radio Observations
  16. GRB 990123, optical monitoring
  17. GRB 990506: BATSE Observations
  18. GRB 990506, optical observations
  19. GRB 990506, Optical Observations
  20. GRB 990506 optical observations
  21. GRB 990506, optical observations
  22. GRB 990506, optical observations from +1 to +3 hours
  23. GRB 990506, optical observations
  24. GRB990506 observation plan
  25. GRB 990316 Optical Observations
  26. GRB 990316, Radio observations
  27. GRB 990316, Optical observations
  28. GRB990316, Optical observations
  29. GRB 990316 optical observations
  30. GRB990316: simultaneous optical observation
  31. GRB990316 - Optical null results
  32. ASM/IPN error box for GRB 990308 (BATSE #7457)
  33. GRB 990308a and GRB 990308b
  34. GRB990308 (Trig. 7457), optical observations
  35. GRB990308, Possible new SGR~0209+70
  36. GRB 990123, Field Photometry
  37. GRB 990217 Optical Observations
  38. BATSE Flight Anomaly
  39. GRB990217: BeppoSAX/GRBM data
  40. GRB990123 observations
  41. GRB990217 Optical observation
  42. GRB990123, Optical Observation
  43. GRB 990123: Discovery of the Probable Host Galaxy
  44. GRB19990123 observations
  45. GRB 990123: BVRI standards in the field
  46. GRB981220, field photometry
  47. GRB990123, Optical observation
  48. GRB990123, 15-GHz limits
  49. GRB 990123: New Constraints on Possible Foreground Galaxies
  50. GRB990123 Optical Observations
  51. GRB990123, Probability of gravitational lensing
  52. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  53. GRB 990123: Continued Radio Observations
  54. GRB990123, Preliminary Lens Search Results
  55. On the Lensing Interpretation of GRB 990123
  56. Search for Potential Images of GRB 990123
  57. GRB990123, Optical BVRI Observations
  58. GRB 990123: near-infrared observations.
  59. GRB990123, OSSE observations
  60. GRB990123: NIR Observation
  61. GRB990123, ASCA X-ray observation of afterglow
  62. "GRB 990123: New BV Observations"
  63. GRB 990123 Optical Follow-Up
  64. GRB 990123: BATSE Observations
  65. GRB990123 IPN annulus
  66. GRB 990123 Spectroscopic Redshifts
  67. GRB 990123: New Optical Observations, Decay Measure
  68. GRB 990123 Optical Follow-Up
  69. GRB 990123: Possible Gravitationally Lensed Burst?
  70. GRB990123, optical observation
  71. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  72. GRB 990123, new radio source
  73. GRB990123, Optical observation
  74. GRB 990123 r-band photometry
  75. GRB 990123 Optical Follow-up
  76. GRB990123 Optical Observation
  77. GRB990123, refined SAX-WFC position
  78. Possible identification of SN1999E with GRB980910
  79. Optical Observations of GRB 981220
  80. GRB 981226: radio variable
  81. GRB981220
  82. GRB 981220 Optical observations
  83. GRB 981226 Optical Observations
  84. GRB981226 Optical Observations
  85. GRB981226 BeppoSAX follow up
  86. GRB 981226
  87. GRB 981226 optical observations
  88. Optical Observations of GRB981226
  89. GRB 981220:Optical Observations
  90. GRB 981226 optical observations
  91. GRB 981220
  92. GRB 981220, radio observations
  93. GRB 981220
  94. GRB 981220, optical observations
  95. GRB 980326/Host Galaxy
  96. GRB981220 IPN error box
  97. GRB 981220: RXTE/ASM and BeppoSAX/GRBM results
  98. BeppoSAX NFI Observation of GRB980425
  99. GRB980329 R,I flux calibration and R,I,K upper limits
  100. GRB980425 Optical Follow-up

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