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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"

36145 results found.

  1. GRB 000926: Preliminary R-band Lightcurve
  2. GRB 000926 HST/Chandra TOO Status
  3. Spectroscopic Redshift of GRB 000926
  4. GRB 000926, Optical Observation
  5. GRB 000926: Optical candidate
  6. Optical candidate for GRB000926
  7. IPN triangulation of GRB000926
  8. GRB 000911, BVRI field photometry
  9. GRB000911: Sub-millimeter observations
  10. IPN triangulation of GRB000925
  11. IPN triangulation of GRB000911
  12. IPN triangulation of GRB000910
  13. False GRB alarm from RXTE/ASM on 8 Sept 2000
  14. GRB 000830: Optical observations
  15. GRB000830: Optical observations
  16. GRB000830, TNG B-band observations
  17. GRB000830, BVRI field photometry
  18. GRB000830: Optical observations
  19. GRB000210, Optical observations
  20. Chandra Position of GRB000210
  21. "Snapshot" afterglow IDs and GRB 000830
  22. IPN triangulation of GRB000830
  23. HST/STIS observations of the host galaxy of GRB 980329
  24. HST/STIS observations of the chaotic environment of GRB 980613
  25. IPN localization of GRB000820
  26. GRB000801 & GRB000730, Gamma Ray Observations
  27. GRB000730, Gamma Ray Observations
  28. GRB000812, Radio observations
  29. IPN localization of GRB000812
  30. IPN localization of GRB000811
  31. GRB000801, Gamma Ray Observations
  32. GRB000801, VLT-Antu R-band observations
  33. GRB 991208 Host Galaxy Imaging
  34. Updated IPN coordinates for GRB000801
  35. IPN localization of GRB000801
  36. IPN localization of GRB000730B
  37. IPN localization of GRB000730B
  38. IPN localization of GRB000730
  39. GRB 990510: Possible detection of a host galaxy
  40. GRB 990510 Host Galaxy Discovery
  41. GRB 000727, optical observations
  42. IPN localization of GRB000727
  43. GRB 990705, HST/STIS observations of the host galaxy
  44. GRB 990712: Late time HST/STIS Observations
  45. GRB 991216, HST/STIS observations
  46. GRB981226, HST/STIS observations of the host galaxy
  47. GRB 000630: Detection of the Optical Afterglow
  48. GRB000630, Revised BVRI Field Photometry
  49. GRB000630, Optical Observations
  50. GRB000630, optical observations
  51. GRB000630, BVRI Field Photometry
  52. GRB000630, optical observations
  53. GRB000630: Optical observations
  54. possible optical counterpart of GRB 000630
  55. IPN triangulation of GRB000630
  56. GRB 000623, optical observations
  57. GRB 000620, optical observations
  58. GRB000418, HST/STIS Observations
  59. GRB990123: Late-time HST/STIS observations of the host
  60. GRB 990506, HST/STIS Observations of the Host Galaxy
  61. GRB000623
  62. GRB 000620: J-band observations
  63. GRB990308, HST/STIS observations of the host galaxy
  64. IPN annulus for GRB000620
  65. GRB000615, Radio observations
  66. GRB000607, optical observations
  67. GRB 000615: NIR further observations
  68. BeppoSAX ALERT: GRB000620
  69. GRB000620: BeppoSAX Alert
  70. GRB990123, HST/STIS observations of the host galaxy
  71. GRB 000615, near-infrared observations
  72. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  73. GRB000616 [IPN Position]
  74. GRB000615B [IPN Position]
  75. GRB000615, further R-band photometry
  76. GRB 000615: NIR observations
  77. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  78. GRB000615, R-band photometry
  79. GRB980425, HST/STIS observations of the host galaxy
  80. GRB000615: BeppoSAX GRB Alert
  81. The Hosts of GRB 980703 and GRB 971214
  82. GRB 000301C: Further Late-Time HST/STIS observations
  83. GRB000528: follow-up X-ray measurements and update of IPN annulus
  84. GRB980519, HST/STIS observations of the host galaxy
  85. GRB000607, Radio Observations
  86. GRB000604 - Optical observations
  87. GRB000607, A SHORT, HARD BURST
  88. GRB000604, optical observations
  89. GRB000528, optical observations at ESO
  90. GRB 000604 optical observations
  91. GRB 000418: Detection of the Host Galaxy
  92. GRB000604, optical observations, comparison with DPOSS
  93. GRB000604 [IPN Position]
  94. X-ray Afterglow of GRB 000529
  95. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  96. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  97. IPN localization and time history of GRB000528
  98. New IPN localization of GRB000529
  99. GRB 000528 - WFC measurements
  100. GRB000528: BeppoSAX GRBM observations

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