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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"

37512 results found.

  1. IPN localization of GRB000811
  2. GRB000801, Gamma Ray Observations
  3. GRB000801, VLT-Antu R-band observations
  4. GRB 991208 Host Galaxy Imaging
  5. Updated IPN coordinates for GRB000801
  6. IPN localization of GRB000801
  7. IPN localization of GRB000730B
  8. IPN localization of GRB000730B
  9. IPN localization of GRB000730
  10. GRB 990510: Possible detection of a host galaxy
  11. GRB 990510 Host Galaxy Discovery
  12. GRB 000727, optical observations
  13. IPN localization of GRB000727
  14. GRB 990705, HST/STIS observations of the host galaxy
  15. GRB 990712: Late time HST/STIS Observations
  16. GRB 991216, HST/STIS observations
  17. GRB981226, HST/STIS observations of the host galaxy
  18. GRB 000630: Detection of the Optical Afterglow
  19. GRB000630, Revised BVRI Field Photometry
  20. GRB000630, Optical Observations
  21. GRB000630, optical observations
  22. GRB000630, BVRI Field Photometry
  23. GRB000630, optical observations
  24. GRB000630: Optical observations
  25. possible optical counterpart of GRB 000630
  26. IPN triangulation of GRB000630
  27. GRB 000623, optical observations
  28. GRB 000620, optical observations
  29. GRB000418, HST/STIS Observations
  30. GRB990123: Late-time HST/STIS observations of the host
  31. GRB 990506, HST/STIS Observations of the Host Galaxy
  32. GRB000623
  33. GRB 000620: J-band observations
  34. GRB990308, HST/STIS observations of the host galaxy
  35. IPN annulus for GRB000620
  36. GRB000615, Radio observations
  37. GRB000607, optical observations
  38. GRB 000615: NIR further observations
  39. BeppoSAX ALERT: GRB000620
  40. GRB000620: BeppoSAX Alert
  41. GRB990123, HST/STIS observations of the host galaxy
  42. GRB 000615, near-infrared observations
  43. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  44. GRB000616 [IPN Position]
  45. GRB000615B [IPN Position]
  46. GRB000615, further R-band photometry
  47. GRB 000615: NIR observations
  48. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  49. GRB000615, R-band photometry
  50. GRB980425, HST/STIS observations of the host galaxy
  51. GRB000615: BeppoSAX GRB Alert
  52. The Hosts of GRB 980703 and GRB 971214
  53. GRB 000301C: Further Late-Time HST/STIS observations
  54. GRB000528: follow-up X-ray measurements and update of IPN annulus
  55. GRB980519, HST/STIS observations of the host galaxy
  56. GRB000607, Radio Observations
  57. GRB000604 - Optical observations
  58. GRB000607, A SHORT, HARD BURST
  59. GRB000604, optical observations
  60. GRB000528, optical observations at ESO
  61. GRB 000604 optical observations
  62. GRB 000418: Detection of the Host Galaxy
  63. GRB000604, optical observations, comparison with DPOSS
  64. GRB000604 [IPN Position]
  65. X-ray Afterglow of GRB 000529
  66. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  67. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  68. IPN localization and time history of GRB000528
  69. New IPN localization of GRB000529
  70. GRB 000528 - WFC measurements
  71. GRB000528: BeppoSAX GRBM observations
  72. GRB 000528 Optical Observations
  73. GRB000519, BVRI field photometry
  74. IPN triangulation of GRB000519
  75. IPN triangulation of GRB000516
  76. Re: GRB000508B : Optical observations
  77. GRB 000418, Optical observation
  78. GRB000508B, optical photometry
  79. GRB000508B, BVR field photometry
  80. Possible GRB-related phenomenon
  81. RXTE/ASM and IPN localization of GRB 000508B
  82. GRB000424, UBVRI field photometry
  83. GRB 000424 Optical Observations
  84. GRB000418, UBVRI field photometry update
  85. The redshift of GRB 000418
  86. GRB 000429, optical observation
  87. GRB 000429, UBVRI field photometry
  88. IPN localization of GRB000429
  89. GRB 000418, UBVRI field photometry
  90. GRB000418, K'-band photometry
  91. GRB 000418, Optical Observation
  92. GRB 000418, optical observation
  93. GRB000424 Optical Observations
  94. GRB 000418, Optical Observation
  95. GRB 000424, Optical Observations
  96. GRB 000418, Optical Observation
  97. GRB000418, near-infrared observations
  98. Correction to IPN error box for GRB000419
  99. IPN error box for GRB000418
  100. GRB000419 [IPN Position]

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