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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"

28053 results found.

  1. GRB001105 BVRI field photometry correction
  2. GRB001105, BVRI field photometry
  3. IPN TRIANGULATION OF GRB001105
  4. GRB 001025B, Optical obervations
  5. GRB 991208: HST Imaging of the Host Galaxy
  6. GRB 001025B, I-band observations
  7. XMM-Newton observation of GRB001025
  8. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  9. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
  10. GRB001007: Optical observations
  11. ASM Localization of GRB 001025
  12. GRB001007, Radio observations
  13. GRB 001018, Possible Radio Afterglow
  14. GRB001018, Gamma Ray Observations
  15. IPN TRIANGULATION OF GRB001019
  16. IPN TRIANGULATION OF GRB001018
  17. IPN TRIANGULATION OF GRB 001017
  18. V,R,I band observations of GRB000926
  19. HETE positions added to GCN
  20. GRB000926 - Amateur Optical Observations
  21. CONCAM null result on GRB001005
  22. IPN triangulation of GRB001005
  23. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  24. GRB000926 - Optical observations
  25. GRB000926 - Optical observations
  26. GRB 000926, Optical Decay
  27. GRB000911: VLT infrared observation
  28. GRB 000926, Optical Observations
  29. GRB000926 K'-band Observation
  30. J and K band observations of GRB 000926
  31. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  32. CONCAM crude optical limits before and after GRB000926
  33. GRB 000926: Preliminary R-band Lightcurve
  34. Spectroscopic Redshift of GRB 000926
  35. GRB 000926: Optical candidate
  36. Optical candidate for GRB000926
  37. GRB 000911, BVRI field photometry
  38. GRB000911, Radio and Optical observations
  39. GRB000911: Optical observations
  40. GRB000830, BVRI field photometry
  41. GRB000210, Optical observations
  42. "Snapshot" afterglow IDs and GRB 000830
  43. GRB000730, Gamma Ray Observations
  44. GRB000812, Radio observations
  45. GRB000801, Gamma Ray Observations
  46. GRB000801, VLT-Antu R-band observations
  47. GRB 991208 Host Galaxy Imaging
  48. IPN localization of GRB000730B
  49. GRB 990510: Possible detection of a host galaxy
  50. GRB 990510 Host Galaxy Discovery
  51. IPN localization of GRB000727
  52. GRB 990712: Late time HST/STIS Observations
  53. GRB 991216, HST/STIS observations
  54. GRB000620, Radio Observations
  55. GRB000630, optical observations
  56. GRB000630, Revised BVRI Field Photometry
  57. GRB000630, Optical Observations
  58. GRB000630, optical observations
  59. GRB000630, optical observations
  60. GRB000630, BVRI Field Photometry
  61. GRB000630, optical observations
  62. GRB000630: Optical observations
  63. GRB000630, Radio Observations
  64. possible optical counterpart of GRB 000630
  65. GRB 000620, optical observations
  66. GRB000418, HST/STIS Observations
  67. GRB990123: Late-time HST/STIS observations of the host
  68. GRB000620, optical observations
  69. GRB000615: H-band observations
  70. GRB990308, HST/STIS observations of the host galaxy
  71. GRB000620 - Optical observations
  72. GRB000620 Optical observations
  73. GRB000620: BeppoSAX WFC and GRBM detection
  74. GRB000607, optical observations
  75. GRB 000615: NIR further observations
  76. GRB990123, HST/STIS observations of the host galaxy
  77. GRB000616 optical observations
  78. GRB 000615, near-infrared observations
  79. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  80. GRB000615, further R-band photometry
  81. GRB 000615: NIR observations
  82. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  83. GRB000615, R-band photometry
  84. The Hosts of GRB 980703 and GRB 971214
  85. GRB 000301C: Further Late-Time HST/STIS observations
  86. GRB000528: follow-up X-ray measurements and update of IPN annulus
  87. GRB980519, HST/STIS observations of the host galaxy
  88. GRB000604 optical non-detection
  89. GRB000604 - Optical observations
  90. GRB000604, optical observations
  91. GRB000528, optical observations at ESO
  92. GRB 000604 optical observations
  93. GRB 000418: Detection of the Host Galaxy
  94. GRB000604, optical observations, comparison with DPOSS
  95. GRB000528, Radio Observations
  96. X-ray Afterglow of GRB 000529
  97. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  98. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  99. GRB 000528 - WFC measurements
  100. GRB000519, BVRI field photometry

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