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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"

35280 results found.

  1. ASM Localization of GRB 001025
  2. GRB001007, Radio observations
  3. IPN TRIANGULATION OF GRB001020
  4. GRB001019, Optical Observations
  5. GRB 001018, Possible Radio Afterglow
  6. GRB001018, Gamma Ray Observations
  7. IPN TRIANGULATION OF GRB001019
  8. IPN TRIANGULATION OF GRB001018
  9. IPN TRIANGULATION OF GRB 001017
  10. GRB 000926: Improved Absorber Redshift
  11. V,R,I band observations of GRB000926
  12. The Likely Optical/Infrared Afterglow of GRB 001011
  13. HETE positions added to GCN
  14. BeppoSAX ALERT: GRB001011
  15. GRB 001007, BVR-band observations
  16. GRB000926 - Amateur Optical Observations
  17. CONCAM null result on GRB001005
  18. IPN triangulation of GRB001007
  19. GRB 000926 : the host galaxy
  20. IPN triangulation of GRB001005
  21. GRB 000926 Chandra Observation
  22. IPN triangulation of GRB 001004
  23. Public availability of BeppoSAX data of GRB000926
  24. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  25. GRB 000926, Optical Decay
  26. GRB000926 - Optical observations
  27. GRB000926 - Optical observations
  28. GRB 000926: optical observations
  29. GRB 000926, Optical Observations
  30. GRB000926 K'-band Observation
  31. GRB000926 : increasing optical decay slope
  32. GRB000926 optical observations
  33. GRB000926 - Optical observations
  34. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  35. J and K band observations of GRB 000926
  36. GRB 000926: Lightcurve Update and Predictions
  37. GRB 000926, optical observation by Oksanen (vsnet-grb)
  38. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  39. CONCAM crude optical limits before and after GRB000926
  40. GRB 000926: Preliminary R-band Lightcurve
  41. GRB 000926 HST/Chandra TOO Status
  42. Spectroscopic Redshift of GRB 000926
  43. GRB 000926, Optical Observation
  44. GRB 000926: Optical candidate
  45. Optical candidate for GRB000926
  46. IPN triangulation of GRB000926
  47. GRB 000911, BVRI field photometry
  48. GRB000911: Sub-millimeter observations
  49. IPN triangulation of GRB000925
  50. IPN triangulation of GRB000911
  51. IPN triangulation of GRB000910
  52. False GRB alarm from RXTE/ASM on 8 Sept 2000
  53. GRB 000830: Optical observations
  54. GRB000830: Optical observations
  55. GRB000830, TNG B-band observations
  56. GRB000830, BVRI field photometry
  57. GRB000830: Optical observations
  58. GRB000210, Optical observations
  59. Chandra Position of GRB000210
  60. "Snapshot" afterglow IDs and GRB 000830
  61. IPN triangulation of GRB000830
  62. HST/STIS observations of the host galaxy of GRB 980329
  63. HST/STIS observations of the chaotic environment of GRB 980613
  64. IPN localization of GRB000820
  65. GRB000801 & GRB000730, Gamma Ray Observations
  66. GRB000730, Gamma Ray Observations
  67. GRB000812, Radio observations
  68. IPN localization of GRB000812
  69. IPN localization of GRB000811
  70. GRB000801, Gamma Ray Observations
  71. GRB000801, VLT-Antu R-band observations
  72. GRB 991208 Host Galaxy Imaging
  73. Updated IPN coordinates for GRB000801
  74. IPN localization of GRB000801
  75. IPN localization of GRB000730B
  76. IPN localization of GRB000730B
  77. IPN localization of GRB000730
  78. GRB 990510: Possible detection of a host galaxy
  79. GRB 990510 Host Galaxy Discovery
  80. GRB 000727, optical observations
  81. IPN localization of GRB000727
  82. GRB 990705, HST/STIS observations of the host galaxy
  83. GRB 990712: Late time HST/STIS Observations
  84. GRB 991216, HST/STIS observations
  85. GRB981226, HST/STIS observations of the host galaxy
  86. GRB 000630: Detection of the Optical Afterglow
  87. GRB000630, Revised BVRI Field Photometry
  88. GRB000630, Optical Observations
  89. GRB000630, optical observations
  90. GRB000630, BVRI Field Photometry
  91. GRB000630, optical observations
  92. GRB000630: Optical observations
  93. possible optical counterpart of GRB 000630
  94. IPN triangulation of GRB000630
  95. GRB 000623, optical observations
  96. GRB 000620, optical observations
  97. GRB000418, HST/STIS Observations
  98. GRB990123: Late-time HST/STIS observations of the host
  99. GRB 990506, HST/STIS Observations of the Host Galaxy
  100. GRB000623

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