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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"

42185 results found.

  1. GRB 990712: Late time HST/STIS Observations
  2. GRB 991216, HST/STIS observations
  3. GRB000620, Radio Observations
  4. GRB981226, HST/STIS observations of the host galaxy
  5. GRB000630, optical observations
  6. GRB 000630: Detection of the Optical Afterglow
  7. GRB000630, Revised BVRI Field Photometry
  8. GRB000630, Optical Observations
  9. GRB000630, optical observations
  10. GRB000630, optical observations
  11. GRB000630, BVRI Field Photometry
  12. GRB000630, optical observations
  13. GRB000630, optical observations
  14. GRB000630: Optical observations
  15. GRB000630, Radio Observations
  16. possible optical counterpart of GRB 000630
  17. GRB 000623, optical observations
  18. GRB 000620, optical observations
  19. GRB000418, HST/STIS Observations
  20. GRB 990506, HST/STIS Observations of the Host Galaxy
  21. GRB000623
  22. GRB000620, optical observations
  23. GRB000615: H-band observations
  24. GRB990308, HST/STIS observations of the host galaxy
  25. GRB000620 - Optical observations
  26. GRB000620 Optical observations
  27. IPN annulus for GRB000620
  28. GRB000620: BeppoSAX WFC and GRBM detection
  29. GRB000615, Radio observations
  30. GRB000607, optical observations
  31. GRB 000615: NIR further observations
  32. GRB990123, HST/STIS observations of the host galaxy
  33. GRB000616 optical observations
  34. GRB 000615, near-infrared observations
  35. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  36. GRB000616 [IPN Position]
  37. GRB000615B [IPN Position]
  38. GRB000615, further R-band photometry
  39. GRB 000615: NIR observations
  40. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  41. GRB000615, R-band photometry
  42. GRB980425, HST/STIS observations of the host galaxy
  43. GRB000615: BeppoSAX GRB Alert
  44. The Hosts of GRB 980703 and GRB 971214
  45. GRB 000301C: Further Late-Time HST/STIS observations
  46. GRB000528: follow-up X-ray measurements and update of IPN annulus
  47. Optical Follow-up of GRB000529 Error Box
  48. GRB980519, HST/STIS observations of the host galaxy
  49. GRB000607, Radio Observations
  50. BeppoSAX X-ray transient/possible GRB000608
  51. GRB000604 optical non-detection
  52. GRB000604 - Optical observations
  53. GRB000604, optical observations
  54. GRB000528, optical observations at ESO
  55. GRB 000604 optical observations
  56. GRB 000418: Detection of the Host Galaxy
  57. GRB000604, optical observations, comparison with DPOSS
  58. X-ray Afterglow of GRB 000529
  59. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  60. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  61. GRB000529: Optical Observations
  62. IPN localization and time history of GRB000528
  63. GRB000519: Optical observations
  64. IPN localization of GRB000529
  65. GRB 000528 - WFC measurements
  66. GRB000529: BeppoSAX WFC position
  67. GRB000528: BeppoSAX GRBM observations
  68. GRB 000528 Optical Observations
  69. GRB000519, BVRI field photometry
  70. Re: GRB000508B : Optical observations
  71. GRB 000418, Optical observation
  72. GRB000508B, optical photometry
  73. GRB000508B, BVR field photometry
  74. Possible GRB-related phenomenon
  75. RXTE/ASM and IPN localization of GRB 000508B
  76. GRB000424, UBVRI field photometry
  77. GRB 000424 Optical Observations
  78. GRB000418, UBVRI field photometry update
  79. The redshift of GRB 000418
  80. GRB000424, optical observations
  81. GRB 000429, optical observation
  82. GRB 000429, UBVRI field photometry
  83. IPN localization of GRB000429
  84. GRB 000418, UBVRI field photometry
  85. GRB000418, Radio detection
  86. GRB000418, K'-band photometry
  87. GRB 000418, Optical Observation
  88. GRB 000418, optical observation
  89. GRB000424 Optical Observations
  90. GRB 000418, Optical Observation
  91. GRB000424, optical observations
  92. GRB000424, optical observations
  93. GRB 000424, Optical Observations
  94. GRB 000418, Optical Observation
  95. GRB000418, near-infrared observations
  96. BeppoSAX GRB000424
  97. Correction to IPN error box for GRB000419
  98. IPN error box for GRB000418
  99. GRB000416 Optical Observations
  100. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134

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