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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"

42753 results found.

  1. GRB 000911, BVRI field photometry
  2. GRB000911: Sub-millimeter observations
  3. IPN triangulation of GRB000925
  4. GRB000911: Optical Transient
  5. GRB000911, Radio and Optical observations
  6. GRB000911, Radio observations
  7. GRB000911: Optical observations
  8. IPN triangulation of GRB000911
  9. IPN triangulation of GRB000910
  10. False GRB alarm from RXTE/ASM on 8 Sept 2000
  11. GRB 000830: Optical observations
  12. GRB000830: Optical observations
  13. GRB000830, TNG B-band observations
  14. GRB000830, BVRI field photometry
  15. GRB000830: Optical observations
  16. GRB000210, Optical observations
  17. Chandra Position of GRB000210
  18. "Snapshot" afterglow IDs and GRB 000830
  19. GRB000830: Optical observations
  20. IPN triangulation of GRB000830
  21. HST/STIS observations of the host galaxy of GRB 980329
  22. HST/STIS observations of the chaotic environment of GRB 980613
  23. IPN localization of GRB000820
  24. SGR 1806-20 burst activity
  25. GRB000812, TNG R-band observations
  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. GRB000301C, UBVI optical observations
  34. GRB000801, Radio Observations
  35. GRB 991208 Host Galaxy Imaging
  36. Updated IPN coordinates for GRB000801
  37. IPN localization of GRB000801
  38. IPN localization of GRB000801
  39. IPN localization of GRB000730B
  40. IPN localization of GRB000730B
  41. IPN localization of GRB000730
  42. GRB 990510: Possible detection of a host galaxy
  43. GRB 990510 Host Galaxy Discovery
  44. GRB 000727, optical observations
  45. IPN localization of GRB000727
  46. GRB 990705, HST/STIS observations of the host galaxy
  47. GRB 990712: Late time HST/STIS Observations
  48. GRB 991216, HST/STIS observations
  49. GRB000620, Radio Observations
  50. GRB981226, HST/STIS observations of the host galaxy
  51. GRB000630, optical observations
  52. GRB 000630: Detection of the Optical Afterglow
  53. GRB000630, Revised BVRI Field Photometry
  54. GRB000630, Optical Observations
  55. GRB000630, optical observations
  56. GRB000630, optical observations
  57. GRB000630, BVRI Field Photometry
  58. GRB000630, optical observations
  59. GRB000630, optical observations
  60. GRB000630: Optical observations
  61. GRB000630, Radio Observations
  62. possible optical counterpart of GRB 000630
  63. IPN triangulation of GRB000630
  64. GRB 000623, optical observations
  65. GRB 000620, optical observations
  66. GRB000418, HST/STIS Observations
  67. GRB990123: Late-time HST/STIS observations of the host
  68. GRB 990506, HST/STIS Observations of the Host Galaxy
  69. GRB000623
  70. GRB 000620: J-band observations
  71. GRB000620, optical observations
  72. GRB000615: H-band observations
  73. GRB990308, HST/STIS observations of the host galaxy
  74. GRB000620 - Optical observations
  75. GRB000620 Optical observations
  76. IPN annulus for GRB000620
  77. GRB000620: BeppoSAX WFC and GRBM detection
  78. GRB000615, Radio observations
  79. GRB000607, optical observations
  80. GRB 000615: NIR further observations
  81. BeppoSAX ALERT: GRB000620
  82. GRB000620: BeppoSAX Alert
  83. GRB990123, HST/STIS observations of the host galaxy
  84. GRB000616 optical observations
  85. GRB 000615, near-infrared observations
  86. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  87. GRB000616 [IPN Position]
  88. GRB000615B [IPN Position]
  89. GRB000615, further R-band photometry
  90. GRB 000615: NIR observations
  91. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  92. GRB000615, R-band photometry
  93. GRB980425, HST/STIS observations of the host galaxy
  94. GRB000615: BeppoSAX GRB Alert
  95. The Hosts of GRB 980703 and GRB 971214
  96. GRB 000301C: Further Late-Time HST/STIS observations
  97. GRB000528: follow-up X-ray measurements and update of IPN annulus
  98. Optical Follow-up of GRB000529 Error Box
  99. GRB980519, HST/STIS observations of the host galaxy
  100. GRB000607, Radio Observations

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