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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"

32505 results found.

  1. CONCAM null result on GRB001005
  2. GRB 000926 : the host galaxy
  3. GRB 000926 Chandra Observation
  4. Public availability of BeppoSAX data of GRB000926
  5. GRB000926: X-ray afterglow by BeppoSAX: revised fluxes (fwd)
  6. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  7. GRB000926 - Optical observations
  8. GRB000926 - Optical observations
  9. GRB 000926, Optical Decay
  10. GRB000911: VLT infrared observation
  11. GRB000926 - Optical observations
  12. GRB000926 - Optical observations
  13. GRB 000926: optical observations
  14. GRB 000926, Optical Observations
  15. GRB000926 - Optical observations
  16. GRB000911: optical VLT observations
  17. GRB000926 : increasing optical decay slope
  18. GRB000926 optical observations
  19. GRB000926 - Optical observations
  20. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  21. J and K band observations of GRB 000926
  22. GRB000911 Optical Observations
  23. GRB 000926: Lightcurve Update and Predictions
  24. GRB 000926, optical observation by Oksanen (vsnet-grb)
  25. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  26. GRB000926: Optical observations
  27. GRB 000926: Preliminary R-band Lightcurve
  28. GRB 000926 HST/Chandra TOO Status
  29. Spectroscopic Redshift of GRB 000926
  30. GRB 000926, Optical Observation
  31. GRB000926, radio observations
  32. GRB 000926: Optical candidate
  33. Optical candidate for GRB000926
  34. IPN triangulation of GRB000926
  35. GRB 000911, BVRI field photometry
  36. GRB000911: Corrected coordinates
  37. GRB000911: Sub-millimeter observations
  38. GRB000911: Optical Transient
  39. GRB000911, Radio and Optical observations
  40. GRB000911, Radio observations
  41. GRB000911: Optical observations
  42. False GRB alarm from RXTE/ASM on 8 Sept 2000
  43. GRB 000830: Optical observations
  44. GRB000830: Optical observations
  45. GRB000830, TNG B-band observations
  46. GRB000830: Optical observations
  47. GRB000210, Optical observations
  48. Chandra Position of GRB000210
  49. GRB000830: Optical observations
  50. HST/STIS observations of the host galaxy of GRB 980329
  51. HST/STIS observations of the chaotic environment of GRB 980613
  52. GRB000812, TNG R-band observations
  53. GRB000801 & GRB000730, Gamma Ray Observations
  54. GRB000812, Radio observations
  55. GRB000801, VLT-Antu R-band observations
  56. GRB000301C, UBVI optical observations
  57. GRB000801, Radio Observations
  58. GRB 991208 Host Galaxy Imaging
  59. Updated IPN coordinates for GRB000801
  60. IPN localization of GRB000801
  61. IPN localization of GRB000730B
  62. GRB 990510: Possible detection of a host galaxy
  63. GRB 990510 Host Galaxy Discovery
  64. GRB 000727, optical observations
  65. GRB 990705, HST/STIS observations of the host galaxy
  66. GRB 990712: Late time HST/STIS Observations
  67. GRB 991216, HST/STIS observations
  68. GRB000620, Radio Observations
  69. GRB981226, HST/STIS observations of the host galaxy
  70. GRB000630, optical observations
  71. GRB 000630: Detection of the Optical Afterglow
  72. GRB000630, Revised BVRI Field Photometry
  73. GRB000630, Optical Observations
  74. GRB000630, optical observations
  75. GRB000630, optical observations
  76. GRB000630, optical observations
  77. GRB000630, optical observations
  78. GRB000630: Optical observations
  79. GRB000630, Radio Observations
  80. possible optical counterpart of GRB 000630
  81. GRB 000623, optical observations
  82. GRB 000620, optical observations
  83. GRB000418, HST/STIS Observations
  84. GRB990123: Late-time HST/STIS observations of the host
  85. GRB 990506, HST/STIS Observations of the Host Galaxy
  86. GRB 000620: J-band observations
  87. GRB000620, optical observations
  88. GRB000615: H-band observations
  89. GRB990308, HST/STIS observations of the host galaxy
  90. GRB000620 - Optical observations
  91. GRB000620 Optical observations
  92. IPN annulus for GRB000620
  93. GRB000615, Radio observations
  94. GRB000607, optical observations
  95. GRB 000615: NIR further observations
  96. GRB990123, HST/STIS observations of the host galaxy
  97. GRB000616 optical observations
  98. GRB 000615, near-infrared observations
  99. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  100. GRB000615, further R-band photometry

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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