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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"

20353 results found.

  1. GRB 990510: Broad Band Break
  2. GRB 990510: BATSE Observations
  3. GRB 990510 optical observations
  4. IPN localization of GRB990510
  5. GRB 990506 Radio Observations
  6. GRB 990123, optical monitoring
  7. GRB 990506: BATSE Observations
  8. GRB 990506, optical observations
  9. GRB 990506, Optical Observations
  10. GRB 990506 optical observations
  11. GRB 990506, optical observations
  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. GRB 990316 Optical Observations
  17. GRB990316, Optical observations
  18. GRB 990316 optical observations
  19. GRB990316: simultaneous optical observation
  20. ASM/IPN error box for GRB 990308 (BATSE #7457)
  21. GRB990308, Possible new SGR~0209+70
  22. GRB 990123, Field Photometry
  23. GRB 990217 Optical Observations
  24. BATSE Flight Anomaly
  25. GRB990123 observations
  26. GRB990123, Optical Observation
  27. GRB 990123: Discovery of the Probable Host Galaxy
  28. GRB19990123 observations
  29. GRB 990123: BVRI standards in the field
  30. GRB 990123: Updated Keck Spectroscopy Results
  31. GRB981220, field photometry
  32. GRB990123, Optical observation
  33. GRB990123, 15-GHz limits
  34. GRB 990123: New Constraints on Possible Foreground Galaxies
  35. GRB990123 Optical Observations
  36. GRB990123, Probability of gravitational lensing
  37. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  38. GRB990123, Preliminary Lens Search Results
  39. Search for Potential Images of GRB 990123
  40. GRB990123, Optical BVRI Observations
  41. GRB 990123: near-infrared observations.
  42. GRB990123, OSSE observations
  43. GRB990123: NIR Observation
  44. "GRB 990123: New BV Observations"
  45. GRB 990123: BATSE Observations
  46. GRB 990123: New Optical Observations, Decay Measure
  47. GRB 990123 Optical Follow-Up
  48. GRB 990123: Possible Gravitationally Lensed Burst?
  49. GRB990123, optical observation
  50. GRB 990123 optical observations
  51. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  52. GRB990123 optical observations
  53. GRB 990123 r-band photometry
  54. GRB 990123 Optical Follow-up
  55. GRB990123 Optical Observation
  56. Possible identification of SN1999E with GRB980910
  57. Optical Observations of GRB 981220
  58. GRB 981226: radio variable
  59. GRB 981226 Optical Observations
  60. GRB981226 Optical Observations
  61. GRB981226 BeppoSAX follow up
  62. GRB 981226 radio observations
  63. GRB 981226
  64. GRB 981226 optical observations
  65. radio observations of GRB 981226
  66. GRB981220 B, R and I band observations
  67. GRB 981220:Optical Observations
  68. GRB 981226 optical observations
  69. GRB 981220, radio observations
  70. GRB 981220, radio observations
  71. GRB 981220
  72. GRB 980326/Host Galaxy
  73. GRB981220 IPN error box
  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. GRB980703 Very Long Baseline Interferometry
  79. GRB970508 optical observations
  80. GRB971214, association with a Galactic star?
  81. GRB980519, Optical Observations
  82. GRB980703, Host galaxy multicolor photometry
  83. GRB980703 - BeppoSAX/GRBM detection
  84. GRB 980703 (NFI observations)
  85. GRB980703 optical photometry
  86. GRB980703 optical observations
  87. GRB980703 Transient Optical Follow-Up
  88. GRB980703: LOTIS observation at early times
  89. GRB980613 Optical Observations
  90. GRB980703 (optical R observations)
  91. BeppoSAX NFI observations of GRB 980703
  92. GRB 980703: ASM Position & Intensity
  93. GRB980703 optical followup
  94. Radio observations of SGRs
  95. SGR1900+14 field optical observations
  96. GRB 980613: Optical transient and its host galaxy
  97. SGR1627-41, RXTE/ASM observations
  98. GRB 980613: Detection of the probable host galaxy
  99. GRB 980613 Optical Observations
  100. GRB 980613 optical observations

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