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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"

39156 results found.

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

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