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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"

32506 results found.

  1. GRB001007: Optical observations
  2. CONCAM null result on GRB001005
  3. GRB 000926 : the host galaxy
  4. GRB 000926 Chandra Observation
  5. Public availability of BeppoSAX data of GRB000926
  6. GRB000926: X-ray afterglow by BeppoSAX: revised fluxes (fwd)
  7. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  8. GRB000926 - Optical observations
  9. GRB000926 - Optical observations
  10. GRB 000926, Optical Decay
  11. GRB000911: VLT infrared observation
  12. GRB000926 - Optical observations
  13. GRB000926 - Optical observations
  14. GRB 000926: optical observations
  15. GRB 000926, Optical Observations
  16. GRB000926 - Optical observations
  17. GRB000911: optical VLT observations
  18. GRB000926 : increasing optical decay slope
  19. GRB000926 optical observations
  20. GRB000926 - Optical observations
  21. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  22. J and K band observations of GRB 000926
  23. GRB000911 Optical Observations
  24. GRB 000926: Lightcurve Update and Predictions
  25. GRB 000926, optical observation by Oksanen (vsnet-grb)
  26. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  27. GRB000926: Optical observations
  28. GRB 000926: Preliminary R-band Lightcurve
  29. GRB 000926 HST/Chandra TOO Status
  30. Spectroscopic Redshift of GRB 000926
  31. GRB 000926, Optical Observation
  32. GRB000926, radio observations
  33. GRB 000926: Optical candidate
  34. Optical candidate for GRB000926
  35. IPN triangulation of GRB000926
  36. GRB 000911, BVRI field photometry
  37. GRB000911: Corrected coordinates
  38. GRB000911: Sub-millimeter observations
  39. GRB000911: Optical Transient
  40. GRB000911, Radio and Optical observations
  41. GRB000911, Radio observations
  42. GRB000911: Optical observations
  43. False GRB alarm from RXTE/ASM on 8 Sept 2000
  44. GRB 000830: Optical observations
  45. GRB000830: Optical observations
  46. GRB000830, TNG B-band observations
  47. GRB000830: Optical observations
  48. GRB000210, Optical observations
  49. Chandra Position of GRB000210
  50. GRB000830: Optical observations
  51. HST/STIS observations of the host galaxy of GRB 980329
  52. HST/STIS observations of the chaotic environment of GRB 980613
  53. GRB000812, TNG R-band observations
  54. GRB000801 & GRB000730, Gamma Ray Observations
  55. GRB000812, Radio observations
  56. GRB000801, VLT-Antu R-band observations
  57. GRB000301C, UBVI optical observations
  58. GRB000801, Radio Observations
  59. GRB 991208 Host Galaxy Imaging
  60. Updated IPN coordinates for GRB000801
  61. IPN localization of GRB000801
  62. IPN localization of GRB000730B
  63. GRB 990510: Possible detection of a host galaxy
  64. GRB 990510 Host Galaxy Discovery
  65. GRB 000727, optical observations
  66. GRB 990705, HST/STIS observations of the host galaxy
  67. GRB 990712: Late time HST/STIS Observations
  68. GRB 991216, HST/STIS observations
  69. GRB000620, Radio Observations
  70. GRB981226, HST/STIS observations of the host galaxy
  71. GRB000630, optical observations
  72. GRB 000630: Detection of the Optical Afterglow
  73. GRB000630, Revised BVRI Field Photometry
  74. GRB000630, Optical Observations
  75. GRB000630, optical observations
  76. GRB000630, optical observations
  77. GRB000630, optical observations
  78. GRB000630, optical observations
  79. GRB000630: Optical observations
  80. GRB000630, Radio Observations
  81. possible optical counterpart of GRB 000630
  82. GRB 000623, optical observations
  83. GRB 000620, optical observations
  84. GRB000418, HST/STIS Observations
  85. GRB990123: Late-time HST/STIS observations of the host
  86. GRB 990506, HST/STIS Observations of the Host Galaxy
  87. GRB 000620: J-band observations
  88. GRB000620, optical observations
  89. GRB000615: H-band observations
  90. GRB990308, HST/STIS observations of the host galaxy
  91. GRB000620 - Optical observations
  92. GRB000620 Optical observations
  93. IPN annulus for GRB000620
  94. GRB000615, Radio observations
  95. GRB000607, optical observations
  96. GRB 000615: NIR further observations
  97. GRB990123, HST/STIS observations of the host galaxy
  98. GRB000616 optical observations
  99. GRB 000615, near-infrared observations
  100. GRB 990123: Late-time HST/STIS 50CCD observations of the host

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Download all Circulars as a .tar.gz archive (updated once a day):
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