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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"

23093 results found.

  1. GRB 001212 possible OA
  2. IPN triangulation of GRB001212
  3. GRB001204, Radio observations
  4. IPN triangulation of GRB001204 (short/hard)
  5. GRB 001105, further optical observations
  6. GRB001120: Gunn-i observations
  7. GRB001120, optical observations
  8. IPN triangulation of GRB001120
  9. Optical/NIR observations of GRB001109
  10. GRB 001109: deep JHK upper limits
  11. GRB 001109 X-ray afterglow with BeppoSAX
  12. GRB001109: Optical observations
  13. GRB001105, BVRI field photometry
  14. GRB 001105, R-band observation
  15. IPN TRIANGULATION OF GRB001105
  16. GRB 001025B, Optical obervations
  17. GRB000926: R-image of the host galaxy
  18. GRB 001025B, I-band observations
  19. XMM-Newton observation of GRB001025
  20. GRB001025B, Radio observations
  21. GRB 001025 Optical Observations
  22. GRB 001025A, optical observation
  23. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  24. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
  25. IPN triangulation of GRB001025
  26. ASM Localization of GRB 001025
  27. IPN TRIANGULATION OF GRB001020
  28. IPN TRIANGULATION OF GRB001019
  29. CORRECTION TO PEAK FLUX OF GRB001018
  30. IPN TRIANGULATION OF GRB001018
  31. IPN TRIANGULATION OF GRB 001017
  32. GRB 000926: Improved Absorber Redshift
  33. V,R,I band observations of GRB000926
  34. The Likely Optical/Infrared Afterglow of GRB 001011
  35. IPN triangulation of GRB001007
  36. GRB 000926 : the host galaxy
  37. IPN triangulation of GRB001005
  38. HETE-2 48 hour Launch Delay
  39. GRB 000926 Chandra Observation
  40. IPN triangulation of GRB 001004
  41. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  42. GRB000926 - Optical observations
  43. GRB000926 - Optical observations
  44. GRB000926 - Optical observations
  45. GRB000926 - Optical observations
  46. GRB000926 - Optical observations
  47. GRB000926 K'-band Observation
  48. GRB000926 optical observations
  49. GRB000926 - Optical observations
  50. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  51. CONCAM crude optical limits before and after GRB000926
  52. GRB 000926: Preliminary R-band Lightcurve
  53. IPN triangulation of GRB000926
  54. IPN triangulation of GRB000926
  55. GRB 000911, BVRI field photometry
  56. IPN triangulation of GRB000925
  57. IPN triangulation of GRB000911
  58. IPN triangulation of GRB000910
  59. False GRB alarm from RXTE/ASM on 8 Sept 2000
  60. GRB 000830: Optical observations
  61. GRB000830, TNG B-band observations
  62. GRB000830, BVRI field photometry
  63. GRB000210, Optical observations
  64. IPN triangulation of GRB000830
  65. IPN localization of GRB000820
  66. GRB000812, TNG R-band observations
  67. GRB000730, Gamma Ray Observations
  68. GRB000812, Radio observations
  69. IPN localization of GRB000812
  70. IPN localization of GRB000811
  71. GRB000801, Gamma Ray Observations
  72. GRB000801, Radio Observations
  73. GRB 991208 Host Galaxy Imaging
  74. Updated IPN coordinates for GRB000801
  75. IPN localization of GRB000801
  76. IPN localization of GRB000730B
  77. IPN localization of GRB000730B
  78. IPN localization of GRB000730
  79. GRB 000727, optical observations
  80. IPN localization of GRB000727
  81. GRB 990705, HST/STIS observations of the host galaxy
  82. GRB 991216, HST/STIS observations
  83. GRB 000630: Detection of the Optical Afterglow
  84. GRB000630, Revised BVRI Field Photometry
  85. GRB000630, optical observations
  86. GRB000630, BVRI Field Photometry
  87. GRB000630, optical observations
  88. GRB000630, optical observations
  89. GRB000630: Optical observations
  90. IPN triangulation of GRB000630
  91. GRB 000623, optical observations
  92. GRB 000620, optical observations
  93. GRB000418, HST/STIS Observations
  94. GRB000623
  95. GRB 000620: J-band observations
  96. GRB000620, optical observations
  97. GRB000615: H-band observations
  98. GRB000620: BeppoSAX WFC and GRBM detection
  99. GRB000615, Radio observations
  100. GRB000607, optical observations

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