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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"

30658 results found.

  1. Chandra Position of GRB000210
  2. GRB000830: Optical observations
  3. HST/STIS observations of the host galaxy of GRB 980329
  4. HST/STIS observations of the chaotic environment of GRB 980613
  5. GRB000812, TNG R-band observations
  6. GRB000801 & GRB000730, Gamma Ray Observations
  7. GRB000812, Radio observations
  8. GRB000801, VLT-Antu R-band observations
  9. GRB000301C, UBVI optical observations
  10. GRB000801, Radio Observations
  11. GRB 991208 Host Galaxy Imaging
  12. Updated IPN coordinates for GRB000801
  13. IPN localization of GRB000801
  14. IPN localization of GRB000730B
  15. GRB 990510: Possible detection of a host galaxy
  16. GRB 990510 Host Galaxy Discovery
  17. GRB 000727, optical observations
  18. GRB 990705, HST/STIS observations of the host galaxy
  19. GRB 990712: Late time HST/STIS Observations
  20. GRB 991216, HST/STIS observations
  21. GRB000620, Radio Observations
  22. GRB981226, HST/STIS observations of the host galaxy
  23. GRB000630, optical observations
  24. GRB 000630: Detection of the Optical Afterglow
  25. GRB000630, Revised BVRI Field Photometry
  26. GRB000630, Optical Observations
  27. GRB000630, optical observations
  28. GRB000630, optical observations
  29. GRB000630, optical observations
  30. GRB000630, optical observations
  31. GRB000630: Optical observations
  32. GRB000630, Radio Observations
  33. possible optical counterpart of GRB 000630
  34. GRB 000623, optical observations
  35. GRB 000620, optical observations
  36. GRB000418, HST/STIS Observations
  37. GRB990123: Late-time HST/STIS observations of the host
  38. GRB 990506, HST/STIS Observations of the Host Galaxy
  39. GRB 000620: J-band observations
  40. GRB000620, optical observations
  41. GRB000615: H-band observations
  42. GRB990308, HST/STIS observations of the host galaxy
  43. GRB000620 - Optical observations
  44. GRB000620 Optical observations
  45. IPN annulus for GRB000620
  46. GRB000615, Radio observations
  47. GRB000607, optical observations
  48. GRB 000615: NIR further observations
  49. GRB990123, HST/STIS observations of the host galaxy
  50. GRB000616 optical observations
  51. GRB 000615, near-infrared observations
  52. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  53. GRB000615, further R-band photometry
  54. GRB 000615: NIR observations
  55. GRB000615, R-band photometry
  56. GRB980425, HST/STIS observations of the host galaxy
  57. The Hosts of GRB 980703 and GRB 971214
  58. GRB 000301C: Further Late-Time HST/STIS observations
  59. GRB000528: follow-up X-ray measurements and update of IPN annulus
  60. Optical Follow-up of GRB000529 Error Box
  61. GRB000607, Radio Observations
  62. GRB000604 optical non-detection
  63. GRB000604 - Optical observations
  64. GRB000604, optical observations
  65. GRB000528, optical observations at ESO
  66. GRB 000604 optical observations
  67. GRB 000418: Detection of the Host Galaxy
  68. GRB000604, optical observations, comparison with DPOSS
  69. GRB000528, Radio Observations
  70. X-ray Afterglow of GRB 000529
  71. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  72. IPN localization and time history of GRB000528
  73. New IPN localization of GRB000529
  74. GRB000519: Optical observations
  75. IPN localization of GRB000529
  76. GRB 000528 - WFC measurements
  77. IPN triangulation of GRB000519
  78. Re: GRB000508B : Optical observations
  79. GRB 000418, Optical observation
  80. GRB000508B, optical photometry
  81. Possible GRB-related phenomenon
  82. GRB 000424 Optical Observations
  83. The redshift of GRB 000418
  84. GRB000424, optical observations
  85. GRB 000429, optical observation
  86. GRB000418, Radio detection
  87. GRB000418, K'-band photometry
  88. GRB 000418, Optical Observation
  89. GRB 000418, optical observation
  90. GRB000424 Optical Observations
  91. GRB 000418, Optical Observation
  92. GRB000424, optical observations
  93. GRB000424, optical observations
  94. GRB 000424, Optical Observations
  95. GRB 000418, Optical Observation
  96. GRB000418, near-infrared observations
  97. BeppoSAX GRB000424
  98. Correction to IPN error box for GRB000419
  99. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  100. RE: Budget cuts in BeppoSAX operations: impact on GRB observation

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