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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"

41192 results found.

  1. GRB000301C, UBVI optical observations
  2. GRB 991208 Host Galaxy Imaging
  3. IPN localization of GRB000730B
  4. GRB 990510: Possible detection of a host galaxy
  5. GRB 990510 Host Galaxy Discovery
  6. GRB 000727, optical observations
  7. GRB 990705, HST/STIS observations of the host galaxy
  8. GRB 990712: Late time HST/STIS Observations
  9. GRB 991216, HST/STIS observations
  10. GRB000620, Radio Observations
  11. GRB981226, HST/STIS observations of the host galaxy
  12. GRB000630, optical observations
  13. GRB 000630: Detection of the Optical Afterglow
  14. GRB000630, Revised BVRI Field Photometry
  15. GRB000630, Optical Observations
  16. GRB000630, optical observations
  17. GRB000630, optical observations
  18. GRB000630, BVRI Field Photometry
  19. GRB000630, optical observations
  20. GRB000630, optical observations
  21. GRB000630: Optical observations
  22. GRB000630, Radio Observations
  23. possible optical counterpart of GRB 000630
  24. GRB 000623, optical observations
  25. GRB 000620, optical observations
  26. GRB000418, HST/STIS Observations
  27. GRB 990506, HST/STIS Observations of the Host Galaxy
  28. GRB000623
  29. GRB000620, optical observations
  30. GRB000615: H-band observations
  31. GRB990308, HST/STIS observations of the host galaxy
  32. GRB000620 - Optical observations
  33. GRB000620 Optical observations
  34. IPN annulus for GRB000620
  35. GRB000620: BeppoSAX WFC and GRBM detection
  36. GRB000615, Radio observations
  37. GRB000607, optical observations
  38. GRB 000615: NIR further observations
  39. GRB990123, HST/STIS observations of the host galaxy
  40. GRB000616 optical observations
  41. GRB 000615, near-infrared observations
  42. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  43. GRB000616 [IPN Position]
  44. GRB000615B [IPN Position]
  45. GRB000615, further R-band photometry
  46. GRB 000615: NIR observations
  47. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  48. GRB000615, R-band photometry
  49. GRB980425, HST/STIS observations of the host galaxy
  50. GRB000615: BeppoSAX GRB Alert
  51. The Hosts of GRB 980703 and GRB 971214
  52. GRB 000301C: Further Late-Time HST/STIS observations
  53. GRB000528: follow-up X-ray measurements and update of IPN annulus
  54. Optical Follow-up of GRB000529 Error Box
  55. GRB980519, HST/STIS observations of the host galaxy
  56. GRB000607, Radio Observations
  57. BeppoSAX X-ray transient/possible GRB000608
  58. GRB000604 optical non-detection
  59. GRB000604 - Optical observations
  60. GRB000604, optical observations
  61. GRB000528, optical observations at ESO
  62. GRB 000604 optical observations
  63. GRB 000418: Detection of the Host Galaxy
  64. GRB000604, optical observations, comparison with DPOSS
  65. X-ray Afterglow of GRB 000529
  66. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  67. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  68. GRB000529: Optical Observations
  69. IPN localization and time history of GRB000528
  70. GRB000519: Optical observations
  71. IPN localization of GRB000529
  72. GRB 000528 - WFC measurements
  73. GRB000529: BeppoSAX WFC position
  74. GRB000528: BeppoSAX GRBM observations
  75. GRB 000528 Optical Observations
  76. GRB000519, BVRI field photometry
  77. Re: GRB000508B : Optical observations
  78. GRB 000418, Optical observation
  79. GRB000508B, optical photometry
  80. GRB000508B, BVR field photometry
  81. Possible GRB-related phenomenon
  82. RXTE/ASM and IPN localization of GRB 000508B
  83. GRB000424, UBVRI field photometry
  84. GRB 000424 Optical Observations
  85. GRB000418, UBVRI field photometry update
  86. The redshift of GRB 000418
  87. GRB000424, optical observations
  88. GRB 000429, optical observation
  89. GRB 000429, UBVRI field photometry
  90. IPN localization of GRB000429
  91. GRB 000418, UBVRI field photometry
  92. GRB000418, Radio detection
  93. GRB000418, K'-band photometry
  94. GRB 000418, Optical Observation
  95. GRB 000418, optical observation
  96. GRB000424 Optical Observations
  97. GRB 000418, Optical Observation
  98. GRB000424, optical observations
  99. GRB000424, optical observations
  100. GRB 000424, Optical Observations

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