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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"

41192 results found.

  1. GRB001120: Optical observations
  2. GRB001109, optical observations
  3. GRB001120, optical observations
  4. WSRT 4.8 GHz observations of GRB001109
  5. IPN triangulation of GRB001120
  6. Optical/NIR observations of GRB001109
  7. GRB 001109: deep JHK upper limits
  8. GRB 001109 X-ray afterglow with BeppoSAX
  9. GRB001109: Optical observations
  10. GRB001109: BeppoSAX/NFI Observations
  11. GRB001109, R-band optical observations
  12. GRB001109, Radio observations
  13. GRB001105, BVRI field photometry
  14. GRB 001105, R-band observation
  15. GRB 001025B, Optical obervations
  16. GRB 991208: HST Imaging of the Host Galaxy
  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. GRB001007: Optical observations
  27. ASM Localization of GRB 001025
  28. GRB001007, Radio observations
  29. GRB001019, Optical Observations
  30. GRB 001018, Possible Radio Afterglow
  31. GRB001018, Gamma Ray Observations
  32. GRB 000926: Improved Absorber Redshift
  33. V,R,I band observations of GRB000926
  34. The Likely Optical/Infrared Afterglow of GRB 001011
  35. HETE positions added to GCN
  36. GRB 001007, BVR-band observations
  37. GRB000926 - Amateur Optical Observations
  38. GRB001007: Optical observations
  39. CONCAM null result on GRB001005
  40. GRB 000926 : the host galaxy
  41. HETE-2 Launches Successfully
  42. GRB 000926 Chandra Observation
  43. IPN triangulation of GRB 001004
  44. GRB000926: X-ray afterglow by BeppoSAX: revised fluxes (fwd)
  45. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  46. GRB000926 - Optical observations
  47. GRB000926 - Optical observations
  48. GRB 000926, Optical Decay
  49. GRB000911: VLT infrared observation
  50. GRB000926 - Optical observations
  51. GRB000926 - Optical observations
  52. GRB 000926: optical observations
  53. GRB 000926, Optical Observations
  54. GRB000926 - Optical observations
  55. GRB000911: optical VLT observations
  56. GRB000926 K'-band Observation
  57. GRB000926 : increasing optical decay slope
  58. GRB000926 optical observations
  59. GRB000926 - Optical observations
  60. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  61. J and K band observations of GRB 000926
  62. GRB000911 Optical Observations
  63. GRB 000926: Lightcurve Update and Predictions
  64. GRB 000926, optical observation by Oksanen (vsnet-grb)
  65. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  66. GRB000926: Optical observations
  67. CONCAM crude optical limits before and after GRB000926
  68. GRB 000926: Preliminary R-band Lightcurve
  69. GRB 000926 HST/Chandra TOO Status
  70. Spectroscopic Redshift of GRB 000926
  71. GRB 000926, Optical Observation
  72. GRB000926, radio observations
  73. GRB 000926: Optical candidate
  74. Optical candidate for GRB000926
  75. IPN triangulation of GRB000926
  76. GRB 000911, BVRI field photometry
  77. GRB000911: Corrected coordinates
  78. GRB000911: Sub-millimeter observations
  79. GRB000911: Optical Transient
  80. GRB000911, Radio and Optical observations
  81. GRB000911, Radio observations
  82. GRB000911: Optical observations
  83. False GRB alarm from RXTE/ASM on 8 Sept 2000
  84. GRB 000830: Optical observations
  85. GRB000830: Optical observations
  86. GRB000830, TNG B-band observations
  87. GRB000830, BVRI field photometry
  88. GRB000830: Optical observations
  89. GRB000210, Optical observations
  90. Chandra Position of GRB000210
  91. "Snapshot" afterglow IDs and GRB 000830
  92. GRB000830: Optical observations
  93. IPN triangulation of GRB000830
  94. HST/STIS observations of the host galaxy of GRB 980329
  95. HST/STIS observations of the chaotic environment of GRB 980613
  96. SGR 1806-20 burst activity
  97. GRB000812, TNG R-band observations
  98. GRB000801 & GRB000730, Gamma Ray Observations
  99. GRB000812, Radio observations
  100. GRB000801, VLT-Antu R-band observations

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